JP5785847B2 - EUV or EB resist composition, resist pattern forming method - Google Patents

Description

  The present invention relates to an EUV or EB resist composition in which an acid is generated by exposure and the solubility in a developing solution is changed by the action of the acid, and a resist pattern forming method using the resist composition.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed and developed to form a resist pattern having a predetermined shape on the resist film. The process to perform is performed. A resist material in which the exposed portion of the resist film changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has been rapidly progressing due to advances in lithography technology.
As a technique for miniaturization, the exposure light source is generally shortened in wavelength (increased energy). Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but at present, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. Further, studies have been made on EUV (extreme ultraviolet), EB (electron beam), X-rays, and the like having a shorter wavelength (higher energy) than these excimer lasers.

Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions.
Conventionally, as a resist material satisfying such requirements, there is a chemically amplified resist composition containing a base material component whose solubility in a developing solution is changed by the action of an acid and an acid generator component that generates an acid upon exposure. It is used. For example, when the developer is an alkali developer (alkaline development process), the positive chemically amplified resist composition includes a resin component (base resin) whose solubility in an alkali developer is increased by the action of an acid, an acid Those containing a generator component are generally used. When a resist film formed using such a resist composition is selectively exposed at the time of resist pattern formation, an acid is generated from the acid generator component in the exposed portion, and the alkali developer of the base resin is generated by the action of the acid. As a result, the exposed area becomes soluble in an alkaline developer. Therefore, by performing alkali development, a positive pattern in which an unexposed portion remains as a pattern is formed.
Here, as the base resin, a resin whose polarity is increased by the action of an acid is used, and the solubility in an alkali developer is increased while the solubility in an organic solvent is decreased. Therefore, when a solvent development process using an organic solvent-containing developer (organic developer) is applied instead of an alkali development process, the solubility in the organic developer is relatively reduced in the exposed area. In the solvent development process, the unexposed portion of the resist film is dissolved and removed by the organic developer, and a negative resist pattern is formed in which the exposed portion remains as a pattern. Such a solvent development process for forming a negative resist pattern is sometimes referred to as a negative development process (for example, Patent Document 1).

  At present, as a base resin of a chemically amplified resist composition used in ArF excimer laser lithography and the like, it has a structural unit derived from (meth) acrylic acid ester in its main chain because of its excellent transparency near 193 nm. Resin (acrylic resin) or the like is generally used (see, for example, Patent Document 2). Here, “(meth) acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. “(Meth) acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position. “(Meth) acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position.

  In recent years, a base resin having an acid-generating group that generates an acid upon exposure has been proposed. For example, a resin component having an acid-generating group that generates an acid upon exposure and an acid-decomposable group that changes its polarity by the action of an acid has been proposed in the structure (see, for example, Patent Documents 3 to 5). Such a resin component has both a function as an acid generator and a function as a base material component, and a chemical amplification resist composition can be constituted by only one component. In other words, when the resin component is exposed to light, an acid is generated from the acid-generating group in the structure, the acid-decomposable group is decomposed by the action of the acid, and a polar group such as a carboxy group is generated to increase the polarity. To do. Therefore, if selective exposure is performed on a resin film (resist film) formed using the resin component, the polarity of the exposed portion increases. Therefore, development using an alkaline developer dissolves the exposed portion. And a positive resist pattern is formed.

As one of the methods for further improving the resolution, exposure (immersion exposure) is performed by interposing a liquid (immersion medium) having a higher refractive index than air between the objective lens of the exposure machine and the sample. There is known a lithography method that performs so-called liquid immersion lithography (hereinafter sometimes referred to as “immersion exposure”). According to immersion exposure, even when a light source having the same exposure wavelength is used, the same high resolution as when using a light source with a shorter wavelength or using a high NA lens can be achieved, and the depth of focus can be reduced. There is no decline. Moreover, immersion exposure can be performed using an existing exposure apparatus. For this reason, immersion exposure has been widely used in recent years because it can realize the formation of a resist pattern with low cost, high resolution, and excellent depth of focus. Immersion exposure is effective in the formation of all pattern shapes, and can be combined with super-resolution techniques such as a phase shift method and a modified illumination method. Currently, as an immersion exposure technique, a technique mainly using an ArF excimer laser as a light source is being actively researched. Currently, water is mainly studied as an immersion medium.
It has been proposed to add a compound containing a fluorine atom or a silicon atom to a resist composition used for such immersion exposure. For example, Patent Document 6 discloses a resist composition to which a polymer compound containing an aromatic cyclic group having a fluorine atom in the side chain is added. Patent Document 7 discloses a resist composition to which a fluorine-containing compound having a group represented by a specific general formula is added.

JP 2009-025723 A JP 2003-241385 A JP-A-10-221852 JP 2006-045311 A JP 2010-095643 A JP 2008-309938 A JP 2009-139909 A

Resist materials used for EUV lithography and EB lithography are required to have lithography characteristics such as sensitivity to EUV and EB and resolution capable of forming a fine resist pattern as a target.
Currently, in EUV lithography and EB lithography, as a resist material, since it has excellent lithography properties, chemical amplification type resists that have been proposed so far for KrF excimer lasers, ArF excimer lasers, etc. are generally used. . In particular, chemically amplified resists containing an acrylic resin as a base resin are said to be excellent in their lithography properties.
However, when a chemically amplified resist proposed for KrF excimer laser, ArF excimer laser, or the like is used for EUV lithography or EB lithography, there is a problem that the lithography characteristics of the formed resist pattern become poor.
For example, in EUV lithography, light of a wavelength outside the EUV region, so-called OoB (Out of Band) light, which is included in light generated from a light source of an EUV exposure apparatus, is a problem. The OoB light enters the unexposed portion of the resist film together with the flare that is generated at the same time (that is, the selectivity of the exposed region at the time of EUV light irradiation is lost), and the acid generator component also in the unexposed portion As a result of decomposition, acid is generated, resulting in a decrease in contrast of the resist pattern, a reduction in film thickness, roughness (roughness of the upper surface of the pattern and the surface of the side wall), and the like. In addition, the roughness causes a defective shape of the resist pattern. For example, the roughness of the pattern side wall surface causes a shape defect represented by non-uniform line width in the line and space pattern, distortion around the hole in the hole pattern, and the like.
The problem of poor lithography characteristics due to OoB light tends to be particularly noticeable when using a chemically amplified resist for a lithography process in which exposure is performed using light having a wavelength in the DUV region such as ArF excimer laser light. is there. That is, the chemically amplified resist generally generates an acid when irradiated with light having a wavelength in the DUV region, and the solubility in the developer changes. OoB light includes EUV around 13.5 nm, DUV of 150 to 300 nm, light in the infrared region, etc., and conventionally used onium salt-based acid generators are light in the wavelength of DUV region. It is easy to generate acid by absorbing. For this reason, a portion that is originally an unexposed portion during EUV exposure is also exposed to cause a decrease in contrast, a decrease in pattern film, and the like.
Also in EB lithography, depending on electron beam irradiation conditions such as acceleration voltage, electrons may diffuse (scatter) on the resist film surface and cause the same problem as the OoB light in the EUV lithography.
The lithography characteristic defect of the resist pattern may adversely affect the formation of fine semiconductor elements. Therefore, a solution of the above problem is required for resist materials used for EUV lithography and EB lithography.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a resist composition useful for EUV or EB, and a resist pattern forming method using the resist composition.

The present inventors incorporated a specific resin component at a specific ratio as an additive into a resist composition containing a resin having a specific structure that generates an acid upon exposure as a base resin. The inventors have found that the above problems can be solved and have completed the present invention.
That is, in the first aspect of the present invention, at least one selected from a base component (A) that generates an acid upon exposure and changes its solubility in a developing solution by the action of the acid, and a fluorine atom and a silicon atom. And a resin component (C) having a polarity conversion group that is decomposed by the action of a base to increase the polarity, and a resist composition for EUV or EB, wherein the base material component (A) is: The polymer component (A1) having a structural unit (a0) having a group represented by the following general formula (a0-1) or (a0-2) is contained, and the resin component (C) is converted into the base material component. (A) It is a resist composition for EUV or EB characterized by containing 1-15 mass parts with respect to 100 mass parts.

［式中、Ｑ^１及びＱ^２はそれぞれ独立に単結合又は２価の連結基である。Ｒ^３、Ｒ^４及びＲ^５はそれぞれ独立に有機基である。ただし、Ｒ^３、Ｒ^４及びＲ ^５ は芳香環を有さない。Ｒ^４とＲ^５とは相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｖ⁻は対アニオンである。Ａ⁻はアニオンを含む有機基である。Ｍ^ｍ＋はｍ価の有機カチオンであり、ｍは１〜３の整数である。ただし、Ｍ ^ｍ＋ は芳香環を有さない。］

[Wherein, Q ¹ and Q ² are each independently a single bond or a divalent linking group. R ³ , R ⁴ and R ⁵ are each independently an organic group. However, R ³ , R ⁴ and R ⁵ do not have an aromatic ring . R ⁴ and R ⁵ may be bonded to each other to form a ring together with the sulfur atom in the formula. V ⁻ is a counter anion. A ^- is an organic group containing anion. M ^{m +} is an m-valent organic cation, and m is an integer of 1 to 3. However, M ^{m +} does not have an aromatic ring . ]

  A second aspect of the present invention is a step of forming a resist film on a support using the resist composition for EUV or EB of the first aspect, a step of exposing the resist film with EUV or EB, And a method of forming a resist pattern by developing the resist film.

In the present specification and claims, “for EUV or EB” means that a resist pattern formed using the resist composition is EUV (extreme ultraviolet) or EB (electron beam) as an exposure light source (radiation source). ) Is used.
“Exposure” is a concept including general irradiation of radiation.
“Aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
The “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified.
The “halogenated alkyl group” is a group in which part or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. The “halogenated alkylene group” is a group in which some or all of the hydrogen atoms of the alkylene group are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
A “fluorinated alkyl group” is a group in which part or all of the hydrogen atoms of an alkyl group are substituted with fluorine atoms. The “fluorinated alkylene group” is a group in which part or all of the hydrogen atoms of the alkylene group are substituted with fluorine atoms.
The “structural unit” means a monomer unit (monomer unit) constituting a resin (polymer compound, polymer, copolymer).

  According to the present invention, it is possible to provide a resist composition useful for EUV or EB, and a resist pattern forming method using the resist composition.

<< Resist Composition of First Aspect >>
The resist composition of the first aspect of the present invention generates a base material component (A) (hereinafter referred to as “component (A)”) that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid. ), And a resin component (C) (hereinafter referred to as “component (C)”) having at least one selected from a fluorine atom and a silicon atom, and a polarity converting group that decomposes by the action of a base and increases its polarity. And).
Since the resist composition of the present invention contains the component (A), it has a property that its solubility in a developing solution is changed by exposure. When a resist film is formed using the resist composition and selective exposure is performed on the resist film, an acid is generated from the component (A) in the exposed portion, and the acid is a developer containing the component (A). Change the solubility in As a result, the solubility of the exposed portion in the developer changes, while the solubility in the unexposed portion does not change in the developer. Therefore, when the resist film is developed, when the resist composition is positive, the exposed portion Is removed by dissolution to form a positive resist pattern. When the resist composition is negative, the unexposed portion is dissolved and removed to form a negative resist pattern.
In this specification, a resist composition in which an exposed portion is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition that forms a negative resist pattern in which an unexposed portion is dissolved and removed. Is referred to as a negative resist composition. The resist composition of the present invention may be a positive resist composition or a negative resist composition. In addition, the resist composition of the present invention may be used for an alkali development process using an alkali developer for development processing at the time of forming a resist pattern, and a developer (organic developer) containing an organic solvent is used for the development processing. It may be for the solvent development process used. Preferably, it is used for forming a positive resist pattern in an alkali development process. In this case, as the component (A), one whose solubility in an alkali developer is increased by the action of an acid is used. It is done.

<(C) component>
The component (C) is a resin component having at least one selected from a fluorine atom and a silicon atom, and a polarity conversion group that is decomposed by the action of a base to increase the polarity.
In the present specification, the “resin component” indicates an organic compound having a film forming ability and a polymer. As the resin component, a polymer compound having a molecular weight of 500 or more, preferably 1000 or more is usually used because a nano-level resist pattern can be easily formed. In the case of the resin component, as the “molecular weight”, a mass average molecular weight in terms of polystyrene by GPC (gel permeation chromatography) is used.

[Polarity-converting group that decomposes by the action of a base to increase polarity]
A polar converting group that is decomposed by the action of a base to increase its polarity (hereinafter sometimes referred to as a base decomposable polar converting group) is an alkaline developer (preferably 2.38 mass% tetramethylammonium hydroxy at 23 ° C. (TMAH aqueous solution) can be decomposed (hydrolyzed). Therefore, since it changes from hydrophobic to hydrophilic before and after alkali development, when forming a resist pattern using a resist composition containing the component (C), the resist pattern surface is hydrophobic to hydrophilic before and after alkali development. To change. Thereby, the occurrence of defects is suppressed, and a resist pattern having a good shape with a small line width roughness (LWR) can be formed.
Examples of the base-decomposable polar conversion group include a group that decomposes by the action of a base to generate a polar group. Examples of the polar group include a carboxy group, a hydroxyl group, and an amino group.
More specifically, examples of the polar conversion group include groups in which at least one of the polar groups of a polar group-containing group having at least one polar group is protected with a base dissociable group. The polar group-containing group may be composed of only a polar group, or may be a group in which n polar groups [n is an integer of 1 or more] bonded to a (n + 1) -valent linking group.
The “base dissociable group” is a group having a base dissociation property at which a bond between at least the base dissociable group and an atom adjacent to the base dissociable group can be cleaved by the action of a base. Is an alkaline developer (for example, 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution at 23 ° C.). The base dissociable group constituting the polar converting group needs to be a group having a lower polarity than the polar group generated by dissociation of the base dissociable group. When dissociated, a polar group having a polarity higher than that of the base dissociable group is generated, and the polarity increases. As a result, the polarity of the entire component (C) increases. As such a base-dissociable group, various types proposed so far can be applied without particular limitation.

  As the base decomposable polarity converting group, groups represented by the following general formulas (I-1) to (I-4) are preferable. Among these, the group represented by general formula (I-1) or (I-2) is preferable, and the group represented by general formula (I-2) is particularly preferable.

［式中、Ｒ^０１は炭素数１〜２のアルキル基または炭素数１〜１０のフッ素化アルキル基であり、Ｌ^０１は単結合または２価の連結基である。Ｒ^０２はフッ素原子を有していてもよい有機基であり、Ｌ^０２は単結合または２価の連結基である。Ｒ^０３はフッ素原子を有していてもよい有機基であり、Ｌ^０３は単結合または２価の連結基である。Ｒ^０４はフッ素原子を有していてもよい有機基であり、Ｌ^０４は単結合または２価の連結基である。］

[Wherein R ⁰¹ represents an alkyl group having 1 to 2 carbon atoms or a fluorinated alkyl group having 1 to 10 carbon atoms, and L ⁰¹ represents a single bond or a divalent linking group. R ⁰² is an organic group that may have a fluorine atom, and L ⁰² is a single bond or a divalent linking group. R ⁰³ is an organic group which may have a fluorine atom, and L ⁰³ is a single bond or a divalent linking group. R ⁰⁴ is an organic group which may have a fluorine atom, and L ⁰⁴ is a single bond or a divalent linking group. ]

In formula (I-1), the fluorinated alkyl group for R ⁰¹ is preferably linear or branched, and more preferably linear. The fluorination rate (ratio in which the hydrogen atom of the unsubstituted alkyl group is substituted with a fluorine atom) is preferably 30% or more, and more preferably 50% or more. The upper limit of the fluorination rate is not particularly limited, and may be 100%.
The fluorinated alkyl group, in ^{_{particular, - (CH 2) v -R}} f [v is an integer from 0 to 4, ^{R f} is a fluorinated alkyl group having 1 to 8 carbon atoms. ] Is preferable. v is preferably an integer of 1 to 3. R ^f preferably has 1 to 2 carbon atoms. In addition, when v is an integer of 1 or more, R ^f is preferably a perfluoroalkyl group.
Specifically, as R ⁰¹ , —CH ₃ , —CH ₂ —CH ₃ , —CF ₃ , —CH ₂ —CF ₃ , —CH ₂ —CF ₂ —CF ₃ , —CH (CF ₃ ) ₂ , — ( _{CH 2) 2 - (CF 2} ) 2 -CF 3, - (CH 2) 2 - (CF 2) 3 -CF 3, - (CH 2) 2 - (CF 2) 4 -CF 3, - (CH 2 ) _2- (CF ₂ ) ₇ -CF ₃ ,-(CH ₂ ) ₃ -CF ₃ ,-(CH ₂ ) ₃ -CF ₂ -CF ₃ ,-(CH ₂ ) ₄ -CF ₃ ,-(CH ₂ ) ₄ -CF ₂ -CF _3, include like.

In formula (I-1), the divalent linking group in L ⁰¹ is not particularly limited, but may be a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like. Are mentioned as preferred.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as the divalent linking group may be an aliphatic hydrocarbon group or an aromatic group.
An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 5 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as - _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.
The linear or branched aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (excluding two hydrogen atoms from the aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched chain fatty acid. Group intervening in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those described above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, Examples include norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

The aromatic group as the divalent hydrocarbon group is a divalent hydrocarbon group having at least one aromatic ring and may have a substituent.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are more preferable, and 6-12 are especially preferable. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; etc. Is mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic group as the divalent hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); A group in which two hydrogen atoms have been removed from an aromatic compound containing a ring (for example, biphenyl, fluorene, etc.); a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group) ) In which one of the hydrogen atoms is substituted with an alkylene group (for example, arylalkyl such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.) Group in which one hydrogen atom is further removed from the aryl group in the group); and the like. The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.
The aromatic group may or may not have a substituent. For example, a hydrogen atom bonded to an aromatic ring of the aromatic group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

(Divalent linking group containing a hetero atom)
The hetero atom in the divalent linking group containing a hetero atom is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, and a silicon atom.
As the divalent linking group containing a hetero atom, specifically, —O—, —C (═O) —, —C (═O) —O—, —O—C (═O) —O—, _{-S -, - S (= O} ) 2 -, - S (= O) 2 -O -, - NH -, - NH-C (= O) -, - NH-C (= NH) -, = N Examples thereof include non-hydrocarbon linking groups such as — and —SiH ₂ —O—, and combinations of at least one of these non-hydrocarbon linking groups and a divalent hydrocarbon group. Examples of the divalent hydrocarbon group include the same divalent hydrocarbon groups that may have a substituent as described above, and a linear or branched aliphatic hydrocarbon group is preferable. .
Among the above, —NH—, —NH—, —NH—C (═NH) — in —C (═O) —NH—, and H in —SiH ₂ —O— are an alkyl group and an acyl, respectively. It may be substituted with a substituent such as a group. The substituent preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Examples of the divalent linking group that is a combination of a non-hydrocarbon linking group and a divalent hydrocarbon group include, for example, —Y ²¹ —O—Y ²² —, — [Y ²¹ —C (═O). —O] _{m ′} —Y ²² —, —Y ²¹ —O—C (═O) —Y ²² — (wherein Y ²¹ and Y ²² each independently have a substituent) A hydrocarbon group, O is an oxygen atom, m ′ is an integer of 0 to 3), — [Y ²³ —O] _{n ′} — (wherein Y ²³ is an alkylene group, and O is oxygen And n ′ is an integer of 1 or more.
The ^{-Y 21 -O-Y 22 -,} - [Y 21 -C (= O) -O] m '-Y 22 - or ^{-Y 21 -O-C (= O} ) -Y 22 - ^{In, Y 21} And Y ²² are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same groups as those described above as the “divalent hydrocarbon group optionally having substituent (s)”.
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
^{- [Y 21 -C (= O} ) -O] m '-Y 22 - In, m' is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, 1 is particularly preferred. ^{That, - [Y 21 -C (=} O) -O] m '-Y 22 - ^{The, -Y 21 -C (= O)} -O-Y 22 - is particularly preferred. Among _{them, - (CH 2) a '} -C (= O) -O- (CH 2) b' - it is preferred. In the formula, a ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.
The _{^{- [Y 23 -O] n '}} - alkylene group for ^{Y 23} is preferably an alkylene group having 1 to 4 carbon atoms.

In formula (I-1), the divalent linking group in L ⁰¹ is a linear or branched alkylene group, a divalent aliphatic cyclic group, or a divalent linking group containing a hetero atom. Preferably, it is a linear or branched alkylene group, more preferably a linear alkylene group.

In formula (I-2), the organic group in R ⁰² may be an organic group having a fluorine atom or an organic group having no fluorine atom, but it should be an organic group having a fluorine atom. preferable. Here, the “organic group having a fluorine atom” refers to a group in which part or all of the hydrogen atoms in the organic group are substituted with fluorine atoms. As the organic group, a monovalent hydrocarbon group which may have a substituent is preferable. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic group.

The aliphatic hydrocarbon group as the monovalent hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like.
The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 5 carbon atoms. The linear or branched aliphatic hydrocarbon group is preferably an alkyl group.
The linear or branched aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).

The aliphatic hydrocarbon group containing a ring in the structure includes a monovalent cyclic aliphatic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), and a monovalent cyclic aliphatic carbon group. A group in which a hydrogen group is bonded to the end of a linear or branched aliphatic hydrocarbon group, or a cyclic aliphatic hydrocarbon group in the middle of a monovalent linear or branched aliphatic hydrocarbon group Examples include an intervening group. Examples of the monovalent linear or branched aliphatic hydrocarbon group include those described above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic aliphatic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.
The cyclic aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

The aromatic group as the monovalent hydrocarbon group is a monovalent hydrocarbon group having at least one aromatic ring and may have a substituent.
It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are more preferable, and 6-12 are especially preferable. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; etc. Is mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic group as the monovalent hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); A group obtained by removing one hydrogen atom from an aromatic compound containing a ring (for example, biphenyl, fluorene, etc.); a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (arylalkyl) Group or heteroarylalkyl group); and the like. The number of carbon atoms of the alkyl group in the arylalkyl group or heteroarylalkyl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1. Specific examples of the arylalkyl group or heteroarylalkyl group include benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group and the like. .
The aromatic group may or may not have a substituent. For example, a hydrogen atom bonded to an aromatic ring of the aromatic group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

R ⁰² is preferably a linear or branched aliphatic hydrocarbon group substituted with a fluorine atom, and more preferably a linear or branched fluorinated alkyl group. The fluorination rate of the fluorinated alkyl group (ratio of hydrogen atoms in the unsubstituted alkyl group substituted by fluorine atoms) is preferably 30% or more, and more preferably 50% or more. The upper limit of the fluorination rate is not particularly limited, and may be 100%.

Wherein ^(I-2), as the divalent linking group for ^{L 02,} are the same as those of the divalent linking group for ^{L 01} in the formula (I-1).
Among them, L ⁰² is preferably a linear or branched alkylene group, a divalent aliphatic cyclic group, or a divalent linking group containing a hetero atom, linear or branched. A chain alkylene group is more preferable, and a linear alkylene group is more preferable.

In formula (I-3), examples of R ⁰³ and L ⁰³ include the same ^groups as R ⁰² and L ⁰² in formula (I-2), respectively.
In formula (I-4), examples of R ⁰⁴ and L ⁰⁴ include the same ^groups as R ⁰² and L ⁰² in formula (I-2), respectively.

  In the component (C), at least one selected from a fluorine atom and a silicon atom and a polar conversion group that is decomposed by the action of a base to increase the polarity may be contained in the same structural unit and are different. It may be contained in the structural unit.

Here, the structural unit constituting the component (C) is not particularly limited, but is preferably a structural unit derived from a compound having an ethylenic double bond.
The “structural unit derived from a compound having an ethylenic double bond” means a structural unit having a structure in which an ethylenic double bond in a compound having an ethylenic double bond is cleaved to form a single bond.
Examples of the compound having an ethylenic double bond include acrylic acid or an ester thereof in which a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the α-position carbon atom. Acrylamide or a derivative thereof optionally substituted with a substituent, a vinyl aromatic compound in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, a cycloolefin or a derivative thereof, a vinyl sulfonate, etc. Is mentioned.
Among these, a hydrogen atom bonded to the α-position carbon atom may be substituted with an acrylic acid or an ester thereof, and a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent. Acrylamide or a derivative thereof, and a vinyl aromatic compound in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent are preferable.

“Acrylic acid ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ ═CH—COOH) is substituted with an organic group.
In the present specification, acrylic acid and acrylic ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as α-substituted acrylic acid and α-substituted acrylic ester, respectively. In addition, acrylic acid and α-substituted acrylic acid may be collectively referred to as “(α-substituted) acrylic acid”, and α-substituted acrylic acid ester may be collectively referred to as “(α-substituted) acrylic acid ester”.
Examples of the substituent bonded to the α-position carbon atom of the α-substituted acrylic acid or ester thereof include a halogen atom, an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group. It is done. Note that the α-position (α-position carbon atom) of a structural unit derived from an acrylate ester means a carbon atom to which a carbonyl group is bonded, unless otherwise specified.
Examples of the halogen atom as the α-position substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Specific examples of the alkyl group having 1 to 5 carbon atoms as the α-position substituent include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, Examples thereof include linear or branched alkyl groups such as isopentyl group and neopentyl group.
Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms as the α-position substituent include a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. Is mentioned. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
The hydroxyalkyl group as the α-position substituent is preferably a hydroxyalkyl group having 1 to 5 carbon atoms, specifically, a part or all of the hydrogen atoms of the above alkyl group having 1 to 5 carbon atoms. Examples thereof include a group substituted with a hydroxy group.
In the present invention, it is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms that is bonded to the α-position carbon atom of (α-substituted) acrylic acid or an ester thereof. It is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and is a hydrogen atom or a methyl group because of industrial availability. Most preferred.
An “organic group” is a group containing a carbon atom and has an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (fluorine atom, chlorine atom, etc.)). Also good.
The organic group of the (α-substituted) acrylate ester is not particularly limited, but includes, for example, the above-described aromatic groups, polar conversion groups, characteristic groups such as acid-decomposable groups described later, and these characteristic groups in the structure. Examples include characteristic group-containing groups. Examples of the characteristic group-containing group include a group in which a divalent linking group is bonded to the characteristic group. Examples of the divalent linking group, for example include the same divalent linking group of L ⁰¹ in the above-mentioned general formula (I-1).

Examples of “acrylamide or a derivative thereof” include an acrylamide in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent (hereinafter sometimes referred to as (α-substituted) acrylamide), (α-substituted) acrylamide. Amino groups (compounds in which one or both of the terminal hydrogen atoms are substituted with a substituent, and the like).
Examples of the substituent that may be bonded to the α-position carbon atom of acrylamide or a derivative thereof are the same as those described as the substituent bonded to the α-position carbon atom of the α-substituted acrylate ester.
As the substituent that substitutes one or both of the hydrogen atoms at the amino group terminal of (α-substituted) acrylamide, an organic group is preferable. Although it does not specifically limit as this organic group, For example, the thing similar to the organic group which the said ((alpha) substituted) acrylate ester has is mentioned.
As the compound in which one or both of the hydrogen atoms at the terminal of the amino group of (α-substituted) acrylamide are substituted with a substituent, for example, —C (= bonded to the α-position carbon atom in the (α-substituted) acrylic acid ester O) —O—, —C (═O) —N (R ^b ) — [wherein R ^b is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ] Are substituted.
In the formula, the alkyl group in R ^b is preferably linear or branched.

The “vinyl aromatic compound” is a compound having an aromatic ring and one vinyl group bonded to the aromatic ring, and examples thereof include styrene or a derivative thereof, vinyl naphthalene or a derivative thereof.
Examples of the substituent that may be bonded to the α-position carbon atom of the vinyl aromatic compound (the carbon atom bonded to the aromatic ring among the carbon atoms of the vinyl group) include the α-position carbon atom of the α-substituted acrylate ester. Examples thereof are the same as those listed as the substituents bonded to.
Hereinafter, a vinyl aromatic compound in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an (α-substituted) vinyl aromatic compound.

As “styrene or a derivative thereof”, a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, or a hydrogen atom bonded to a benzene ring may be substituted with a substituent other than a hydroxyl group. Good styrene (hereinafter, also referred to as (α-substituted) styrene), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the benzene ring is other than a hydroxyl group Hydroxystyrene which may be substituted with a substituent (hereinafter also referred to as (α-substituted) hydroxystyrene), (α-substituted) a compound in which the hydrogen atom of the hydroxyl group of hydroxystyrene is substituted with an organic group, The hydrogen atom bonded to the carbon atom may be substituted with a substituent, and the hydrogen atom bonded to the benzene ring may be substituted with a substituent other than a hydroxyl group and a carboxy group. Sulfonyl benzoic acid (hereinafter sometimes referred to (alpha-substituted) vinyl benzoic acid.), (Alpha-substituted) hydrogen atom of the carboxyl group of the vinyl benzoate compounds substituted with organic groups, and the like.
Hydroxystyrene is a compound in which one vinyl group and at least one hydroxyl group are bonded to a benzene ring. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a benzene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the benzene ring is not particularly limited. When the number of hydroxyl groups is one, the para 4-position of the vinyl group bonding position is preferred. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.
Vinyl benzoic acid is a compound in which one vinyl group is bonded to the benzene ring of benzoic acid. The bonding position of the vinyl group in the benzene ring is not particularly limited.
The substituent other than the hydroxyl group and the carboxy group that may be bonded to the benzene ring of styrene or a derivative thereof is not particularly limited, and examples thereof include a halogen atom, an alkyl group having 1 to 5 carbon atoms, and an alkyl group having 1 to 5 carbon atoms. Examples include halogenated alkyl groups. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
The organic group in the compound in which the hydrogen atom of the hydroxyl group of (α-substituted) hydroxystyrene is substituted with an organic group is not particularly limited, and examples thereof include the organic groups mentioned as the organic group of the (α-substituted) acrylate ester. It is done.
The organic group in the compound in which the hydrogen atom of the carboxy group of (α-substituted) vinylbenzoic acid is substituted with an organic group is not particularly limited. For example, the organic groups mentioned as the organic group of the (α-substituted) acrylic acid ester Is mentioned.

As "vinyl naphthalene or a derivative thereof", the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and the hydrogen atom bonded to the naphthalene ring is substituted with a substituent other than a hydroxyl group. A good vinyl naphthalene (hereinafter sometimes referred to as (α-substituted) vinyl naphthalene), a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring is Vinyl (hydroxynaphthalene) optionally substituted with a substituent other than a hydroxyl group (hereinafter sometimes referred to as (α-substituted) vinyl (hydroxynaphthalene)), (α-substituted) hydrogen atom of hydroxyl group of vinyl (hydroxynaphthalene) Are compounds substituted with a substituent, and the like.
Vinyl (hydroxynaphthalene) is a compound in which one vinyl group and at least one hydroxyl group are bonded to a naphthalene ring. The vinyl group may be bonded to the 1-position of the naphthalene ring or may be bonded to the 2-position. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a naphthalene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the naphthalene ring is not particularly limited. In the case where a vinyl group is bonded to the 1-position or 2-position of the naphthalene ring, any one of the 5- to 8-positions of the naphthalene ring is preferable. In particular, when the number of hydroxyl groups is one, any one of 5 to 7 positions of the naphthalene ring is preferable, and 5 or 6 positions are preferable. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.
Examples of the substituent which may be bonded to the naphthalene ring of vinyl naphthalene or a derivative thereof are the same as those described above as the substituent which may be bonded to the benzene ring of the (α-substituted) styrene.
The organic group in the compound in which the hydrogen atom of the hydroxyl group of (α-substituted) vinyl (hydroxynaphthalene) is substituted with an organic group is not particularly limited. For example, the same organic group as the (α-substituted) acrylic acid ester has Is mentioned.

Specific examples of structural units derived from (α-substituted) acrylic acid or esters thereof include structural units represented by the following general formula (U-1).
Specific examples of the structural unit derived from the structural unit derived from (α-substituted) acrylamide or a derivative thereof include a structural unit represented by the following general formula (U-2).
Among the (α-substituted) vinyl aromatic compounds, specific examples of the structural unit derived from (α-substituted) styrene or a derivative thereof include a structural unit represented by the following general formula (U-3). Specific examples of the structural unit derived from (α-substituted) vinylnaphthalene or a derivative thereof include a structural unit represented by the following general formula (U-4).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。Ｘ^ａ〜Ｘ^ｄはそれぞれ独立に水素原子または有機基である。Ｒ^ｂは水素原子または炭素数１〜５のアルキル基である。Ｒ^ｃおよびＲ^ｄはそれぞれ独立にハロゲン原子、−ＣＯＯＸ^ｅ（Ｘ^ｅは水素原子または有機基である。）、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。ｐｘは０〜３の整数であり、ｑｘは０〜５の整数であり、ｐｘ＋ｑｘは０〜５である。ｑｘが２以上の整数である場合、複数のＲ^ｃはそれぞれ同じであっても異なってもよい。ｘは０〜３の整数であり、ｙは０〜３の整数であり、ｚは０〜４の整数であり、ｘ＋ｙ＋ｚは０〜７である。ｙ＋ｚが２以上の整数である場合、複数のＲ^ｄはそれぞれ同じであっても異なってもよい。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. X ^{a to} X ^d are each independently a hydrogen atom or an organic group. R ^b is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ^c and R ^d are each independently a halogen atom, —COOX ^e (X ^e is a hydrogen atom or an organic group), an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. . px is an integer of 0 to 3, qx is an integer of 0 to 5, and px + qx is 0 to 5. When qx is an integer of 2 or more, the plurality of R ^c may be the same or different. x is an integer of 0-3, y is an integer of 0-3, z is an integer of 0-4, and x + y + z is 0-7. When y + z is an integer of 2 or more, the plurality of R ^d may be the same or different. ]

The component (C) has at least a structural unit containing a fluorine atom or a silicon atom (hereinafter referred to as a structural unit (c0)).
The structural unit (c0) is not particularly limited as long as it contains a fluorine atom or a silicon atom, but is preferably a structural unit derived from a compound having an ethylenic double bond. The structural unit represented by 0) is preferred.

［式中、Ｒは、水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｌ^０は、フッ素原子もしくはケイ素原子を有してもよい２価の連結基、または単結合であり、Ｒ^０は、フッ素原子またはケイ素原子を有してもよい１価の有機基である。ただしＬ^０およびＲ^０の少なくとも一方は、フッ素原子またはケイ素原子を有する。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, and L ⁰ is a divalent which may have a fluorine atom or a silicon atom. A linking group or a single bond, R ⁰ is a monovalent organic group which may have a fluorine atom or a silicon atom. However, at least one of L ⁰ and R ⁰ has a fluorine atom or a silicon atom. ]

In formula (c-0), the alkyl group and halogenated alkyl group in R are the alkyl groups and halogenated alkyls mentioned as the substituent bonded to the α-position carbon atom of the α-substituted acrylic acid or ester thereof, respectively. The same thing as a group is mentioned.
Examples of the divalent linking group for L ⁰ include the same divalent linking groups as for L ⁰¹ in the formula (I-1). Of ^{these, -C (= O) -O-} L 10 -, - C (= O) -N (R N) -L 10 - or ^-R ar ^{-L 10} - group represented by are preferred.
L ¹⁰ is a single bond or a divalent linking group. Examples of the divalent linking group include the same divalent linking groups as those represented by L ⁰¹ in formula (I-1).
^RN is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group is preferably linear or branched. The R ^N, a hydrogen atom or a methyl group is particularly preferred.
R ^ar is a divalent aromatic group which may have a substituent. Examples of the divalent aromatic group include the same aromatic groups as those described as the divalent hydrocarbon group in the description of the divalent linking group in L ⁰¹ in the general formula (I-1). It is done. Especially, the phenylene group which may have a substituent, or the naphthylene group which may have a substituent is preferable.
The organic group in R ⁰ is not particularly limited, and an organic group containing a characteristic group corresponding to the desired characteristic of the component (C) can be appropriately selected from known organic groups. For example, characteristic groups (base-decomposable polar conversion group, acid-decomposable group, polar group-containing hydrocarbon group, etc.) contained in the side chain of structural units (c1) to (c6) to be described later can be mentioned.

More specific examples of the structural unit constituting the component (C) include the following structural units (c1) to (c5).
Structural unit (c1): a fluorine-containing structural unit containing a base-decomposable polar conversion group.
Structural unit (c2): a structural unit containing an acid-decomposable group that is decomposed by the action of an acid to increase its polarity.
Structural unit (c3): a structural unit containing a polar group.
Structural unit (c4): a fluorine-containing structural unit containing a ring structure and not corresponding to the structural units (c1) to (c3).
Structural unit (c5): a silicon-containing structural unit containing an organic group having a trialkylsilyl group or a siloxane bond (Si—O—Si).

[Structural unit (c1)]
The base-decomposable polarity converting group in the structural unit (c1) is the same as the base-decomposable polarity-converting group mentioned above.
Examples of the structural unit (c1) include those in which R ⁰ in the general formula (c-0) is a base-decomposable polar conversion group, and preferred examples thereof include the following general formula (c1-10) or (c1- 20) and the like.

［式（ｃ１−１０）中、Ｒ、Ｌ^０、Ｌ^０１、Ｒ^０１はそれぞれ前記と同じである。ただしＬ^０、Ｌ^０１およびＲ^０１のうち少なくとも一つはフッ素原子を有する。式（ｃ１−２０）中、Ｒ、Ｌ^０、Ｌ^０２、Ｒ^０２はそれぞれ前記と同じである。ただしＬ^０、Ｌ^０２およびＲ^０２のうち少なくとも一つはフッ素原子を有する。］

[In the formula (c1-10), R, L ⁰ , L ⁰¹ and R ⁰¹ are the same as defined above. However, at least one of L ⁰ , L ⁰¹ and R ⁰¹ has a fluorine atom. In formula (c1-20), R, L ⁰ , L ⁰² and R ⁰² are the same as defined above. However, at least one of L ⁰ , L ⁰² and R ⁰² has a fluorine atom. ]

Wherein, R, ^{L 0} is the same each R in formula (c-0), and ^{L 0.}
L ^{01, R 01} are each the same as ^{L 01, R 01} in the general formula (I-1).
L ^{02, R 02} are each the same as ^{L 02, R 02} in the general formula (I-2).

  As preferable examples of the structural unit represented by the general formula (c1-10) or (c1-20), the following general formulas (c1-11) to (c1-15), (c1-21) to (c1-25) ) And the like.

［式（ｃ１−１１）〜（ｃ１−１２）中、Ｒ、Ｒ^０１はそれぞれ前記と同じであり、Ｌ^１１は単結合または２価の連結基であり、Ｒ^ａｒは置換基を有していてもよい２価の芳香族基であり、Ｌ^１２は単結合または２価の連結基であり、Ｒ^Ｎは水素原子または炭素数１〜５のアルキル基である。ただしＬ^１１、Ｒ^ａｒ、Ｌ^１２およびＲ^０１のうち少なくとも一つはフッ素原子を有する。
式（ｃ１−１３）中、Ｒ、Ｒ^ａｒ、Ｒ^０１はそれぞれ前記と同じであり、Ｌ^１３は単結合または２価の連結基である。ただしＲ^ａｒ、Ｌ^１３およびＲ^０１のうち少なくとも一つはフッ素原子を有する。
式（ｃ１−１４）〜（ｃ１−１５）中、Ｒ、Ｒ^０１、Ｒ^Ｎはそれぞれ前記と同じであり、Ｌ^１４は芳香族基を含まない２価の連結基である。ただしＬ^１４およびＲ^０１のうち少なくとも一つはフッ素原子を有する。
式（ｃ１−２１）〜（ｃ１−２２）中、Ｒ、Ｒ^ａｒ、Ｒ^０２、Ｒ^Ｎはそれぞれ前記と同じであり、Ｌ^２１は単結合または２価の連結基である。ただしＬ^２１、Ｒ^ａｒおよびＲ^０２のうち少なくとも一つはフッ素原子を有する。
式（ｃ１−２３）中、Ｒ、Ｒ^ａｒ、Ｒ^０２はそれぞれ前記と同じである。ただしＲ^ａｒおよびＲ^０２のうち少なくとも一つはフッ素原子を有する。
式（ｃ１−２４）〜（ｃ１−２５）中、Ｒ、Ｒ^０２、Ｒ^Ｎはそれぞれ前記と同じであり、Ｌ^２２は芳香族基を含まない２価の連結基である。ただしＬ^２２およびＲ^０２のうち少なくとも一つはフッ素原子を有する。］

[In the formulas (c1-11) to (c1-12), R and R ⁰¹ are the same as defined above, L ¹¹ is a single bond or a divalent linking group, and R ^ar has a substituent. And L ¹² is a single bond or a divalent linking group, and ^RN is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. However, at least one of L ¹¹ , R ^ar , L ¹² and R ⁰¹ has a fluorine atom.
In formula (c1-13), R, R ^ar and R ⁰¹ are the same as defined above, and L ¹³ represents a single bond or a divalent linking group. However, at least one of R ^ar , L ¹³ and R ⁰¹ has a fluorine atom.
Wherein ^{(c1-14) ~ (c1-15),} R, R 01, R N are the same as defined ^{above, L 14} is a divalent linking group that does not contain an aromatic group. However, at least one of L ¹⁴ and R ⁰¹ has a fluorine atom.
Wherein ^{(c1-21) ~ (c1-22),} R, R ar, R 02, R N are the same as defined ^{above, L 21} is a single bond or a divalent linking group. However, at least one of L ²¹ , R ^ar and R ⁰² has a fluorine atom.
In formula (c1-23), R, R ^ar and R ⁰² are the same as defined above. However, at least one of R ^ar and R ⁰² has a fluorine atom.
Wherein ^{(c1-24) ~ (c1-25),} R, R 02, R N are the same as defined ^{above, L 22} is a divalent linking group that does not contain an aromatic group. However, at least one of L ²² and R ⁰² has a fluorine atom. ]

In the formula, R is the same as R in the formula (c-0).
R ⁰¹ is the basic degradable polarity conversion group formula mentioned in the description of the same as that ^{R 01} of (I-1) ^{in, R 02} is the same as in the general formula (I-2) ^{R 02} in is there.
R ^ar is, ^-R ar ^{-L 10} mentioned in the description of the divalent linking group for ^{L 01} in the formula (I-1) in - is the same as ^{R ar} in.
R ^N is the formula -C mentioned in the description of the divalent linking group for (I-1) ^{L 01} in ^{(= O) -N (R N} ) -L 10 - is the same as ^{R N} in.
Examples of the divalent linking group in L ¹¹ and L ²¹ include the same divalent linking groups as those in L ⁰¹ in the general formula (I-1). Of these, a linear or branched alkylene group is preferable, and a linear alkylene group is more preferable. Of these, a methylene group is particularly preferable.
Examples of the divalent linking group in L ¹² and L ¹³ include the same divalent linking groups as those in L ⁰¹ in the general formula (I-1). Among them, those containing an ether bond or an ester bond are preferable, and —O— (CH ₂ ) _a1 —, —O—C (═O) — (CH ₂ ) _a1 —, — (CH ₂ ) _a2 —O— ( CH ₂ ) _a1 — or — (CH ₂ ) _a2 —O—C (═O) — (CH ₂ ) _a1 — is more preferred, and —O— (CH ₂ ) _a1 — is particularly preferred. In the formula, a1 is an integer of 1 to 5, and a2 is an integer of 1 to 5.
The divalent linking group in L ¹⁴ and L ²² is the same as the divalent linking group in L ⁰¹ in the general formula (I-1) (excluding those containing an aromatic group). Is mentioned. Among these, a linear or branched alkylene group which may have a fluorine atom, a divalent aliphatic cyclic group, or a divalent linking group containing a hetero atom is preferable. A linear or branched alkylene group which may have a phenoxy group is more preferable. Among them, linear alkylene group or branched alkylene group in which a fluorine atom or a fluorinated alkyl group on the carbon atom attached adjacent to the carbonyl group, _{preferably, -CH 2 -, - CH 2} -CH 2 - _{, -CH (CH 3) -CF 2} -, - CH (CH 2 CH 3) -CF 2 -, or _{-CH (CH 2 CH 3) -CF} (CH 3) - it is particularly preferred.

As the structural unit (c1), among the above, the structural unit represented by the general formula (c1-11), (c1-12), (c1-14), (c1-15), or (c1-23) preferable. Preferred specific examples of these structural units are shown below. In the formula, ^Rβ is a hydrogen atom or a methyl group.

When the component (C) contains the structural unit (c1), the structural unit (c1) contained in the component (C) may be one type or two or more types.
In the component (C), the proportion of the structural unit (c1) is preferably 40 to 90 mol%, more preferably 50 to 85 mol%, and more preferably 50 to 80 mol% with respect to all the structural units constituting the component (C). Is more preferable. By setting it to the lower limit or more, the surface segregation effect is enhanced, the solubility in an alkali developer is improved, and the lithography properties are improved. Moreover, the balance with another structural unit can be taken by making it below an upper limit.

[Structural unit (c2)]
The structural unit (c2) is a structural unit containing an acid-decomposable group (acid-decomposable polarity converting group) that is decomposed by the action of an acid and increases in polarity.
The “acid-decomposable group” means that at least a part of the bond in the structure of the acid-decomposable group is formed by the action of an acid generated from the component (A) or the optionally added acid generator component (B) by exposure. It is a group having acid decomposability that can be cleaved.
Examples of the acid-decomposable group whose polarity increases by the action of an acid include a group that decomposes by the action of an acid to generate a polar group.
Examples of the polar group constituting the acid-decomposable group include a carboxy group, a hydroxyl group, an amino group, a sulfo group (—SO ₃ H), and the like. Among these, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specifically, examples of the acid-decomposable group include a group in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of the polar group is protected with an acid-dissociable group).
The “acid-dissociable group” is at least adjacent to the acid-dissociable group and the acid-dissociable group by the action of an acid generated from the component (A) or the optionally added acid generator component (B) by exposure. It is a group having acid dissociation properties that can cleave the bond with the atom. The acid-dissociable group constituting the acid-decomposable group must be a group having a lower polarity than the polar group generated by dissociation of the acid-dissociable group. Is dissociated, a polar group having a polarity higher than that of the acid dissociable group is generated, and the polarity of the component (C) is increased.
When the polarity of the component (C) is increased during exposure, the solubility of the exposed portion in the alkaline developer is improved in the case of an alkali development process.

The acid-dissociable group is not particularly limited, and those that have been proposed as acid-dissociable groups for base resins for chemically amplified resists can be used. In general, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in (meth) acrylic acid or the like, an acetal type acid dissociable group such as an alkoxyalkyl group, and the like are widely known.
Here, the “tertiary alkyl ester” is an ester formed by replacing a hydrogen atom of a carboxy group with a chain or cyclic alkyl group, and the carbonyloxy group (—C (═O The structure in which the tertiary carbon atom of the chain or cyclic alkyl group is bonded to the terminal oxygen atom of) -O-). In this tertiary alkyl ester, when an acid acts, a bond is cut between an oxygen atom and a tertiary carbon atom to form a carboxy group.
The chain or cyclic alkyl group may have a substituent.
Hereinafter, a group that is acid dissociable by constituting a carboxy group and a tertiary alkyl ester is referred to as a “tertiary alkyl ester type acid dissociable group” for convenience.

Examples of the tertiary alkyl ester type acid dissociable group include an aliphatic branched acid dissociable group and an acid dissociable group containing an aliphatic cyclic group.
Here, “aliphatic branched” means having a branched structure having no aromaticity. The structure of the “aliphatic branched acid dissociable group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
Examples of the aliphatic branched acid dissociable group include a group represented by —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ). ^Wherein, R 71 ^{to R 73} each independently represents a linear alkyl group of 1 to 5 carbon atoms. The group represented by —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ) preferably has 4 to 8 carbon atoms, specifically a tert-butyl group or a 2-methyl-2-butyl group. , 2-methyl-2-pentyl group, 3-methyl-3-pentyl group and the like. A tert-butyl group is particularly preferable.
In the aliphatic branched acid dissociable group used for the structural unit (c2), part of the hydrogen atoms may be substituted with a fluorine atom. In this case, one of R ⁷¹ , R ⁷² and R ^{73 in} the group represented by —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ) is a fluorinated alkyl group, and two are alkyl groups. It is preferable. The fluorinated alkyl group is preferably a group represented by — (CH ₂ ) _w —CF ₃ . w is an integer of 0-3.

The “aliphatic cyclic group” means a monocyclic group or a polycyclic group having no aromaticity.
The aliphatic cyclic group in the “acid-dissociable group containing an aliphatic cyclic group” may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and an oxygen atom (= O).
The basic ring structure excluding the substituent of the aliphatic cyclic group is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The hydrocarbon group may be either saturated or unsaturated, but is usually preferably saturated.
The aliphatic cyclic group may be monocyclic or polycyclic.
As the aliphatic cyclic group, those having 3 to 30 carbon atoms are preferable, those having 5 to 30 are more preferable, 5 to 20 are more preferable, 6 to 15 are particularly preferable, and 6 to 12 is most preferable. . As the monocyclic aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like. Moreover, a part of carbon atoms constituting the ring of these aliphatic cyclic groups may be substituted with an ether group (—O—).

Examples of the acid dissociable group containing an aliphatic cyclic group include:
(I) a substituent on a carbon atom bonded to an atom (for example, —O— in —C (═O) —O—) adjacent to the acid dissociable group on the ring skeleton of the monovalent aliphatic cyclic group A group in which (atom or group other than hydrogen atom) is bonded to form a tertiary carbon atom;
(Ii) a group having a monovalent aliphatic cyclic group and a branched alkylene having a tertiary carbon atom bonded thereto.
In the group (i), examples of the substituent bonded to the carbon atom bonded to the atom adjacent to the acid dissociable group on the ring skeleton of the aliphatic cyclic group include an alkyl group. Examples of the alkyl group include those similar to R ¹⁴ in formulas (1-1) to (1-9) described later.
Specific examples of the group (i) include groups represented by the following general formulas (1-1) to (1-9).
Specific examples of the group (ii) include groups represented by the following general formulas (2-1) to (2-6).

［式中、Ｒ^１４はアルキル基であり、ｇは０〜８の整数である。］

[Wherein, R ¹⁴ represents an alkyl group, and g represents an integer of 0 to 8. ]

［式中、Ｒ^１５およびＲ^１６は、それぞれ独立してアルキル基である。］

[Wherein, R ¹⁵ and R ¹⁶ each independently represents an alkyl group. ]

In formulas (1-1) to (1-9), the alkyl group of R ¹⁴ may be linear, branched or cyclic, and is preferably linear or branched.
The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and still more preferably 1 or 2. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.
The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group and the like, and isopropyl group is most preferable.
g is preferably an integer of 0 to 3, more preferably an integer of 1 to 3, and still more preferably 1 or 2.
In formulas (2-1) to (2-6), examples of the alkyl group for R ^{15 to} R ¹⁶ include the same alkyl groups as those described above for R ¹⁴ .
In the formulas (1-1) to (1-9) and (2-1) to (2-6), a part of the carbon atoms constituting the ring is substituted with an etheric oxygen atom (—O—). May be.
In formulas (1-1) to (1-9) and (2-1) to (2-6), a hydrogen atom bonded to a carbon atom constituting the ring may be substituted with a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, and a fluorinated alkyl group.

The “acetal-type acid dissociable group” is generally bonded to an oxygen atom by substituting a hydrogen atom at the terminal of an OH-containing polar group such as a carboxy group or a hydroxyl group. When an acid is generated by exposure, this acid acts to break the bond between the acetal type acid dissociable group and the oxygen atom to which the acetal type acid dissociable group is bonded. OH-containing polar groups are formed.
Examples of the acetal type acid dissociable group include a group represented by the following general formula (p1).

［式中、Ｒ^１’，Ｒ^２’はそれぞれ独立して水素原子または炭素数１〜５のアルキル基を表し、ｎは０〜３の整数を表し、Ｙは炭素数１〜５のアルキル基または脂肪族環式基を表す。］

[Wherein, R ¹ ′ and R ² ′ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n represents an integer of 0 to 3, and Y represents an alkyl group having 1 to 5 carbon atoms. Or represents an aliphatic cyclic group. ]

In formula (p1), n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.
Examples of the alkyl group for R ¹ ′ and R ² ′ include the same alkyl groups listed as the substituents that may be bonded to the α-position carbon atom in the description of the α-substituted acrylate ester. A methyl group or an ethyl group is preferred, and a methyl group is most preferred.
In the present invention, it is preferable that at least one of R ¹ ′ and R ² ′ is a hydrogen atom. That is, the acid dissociable group (p1) is preferably a group represented by the following general formula (p1-1).

［式中、Ｒ^１’、ｎ、Ｙは上記と同じである。］

[Wherein R ¹ ′, n and Y are the same as described above. ]

Examples of the alkyl group for Y include the same alkyl groups as those described above for the substituent that may be bonded to the carbon atom at the α-position in the description of the α-substituted acrylate ester.
The aliphatic cyclic group for Y can be appropriately selected and used from monocyclic or polycyclic aliphatic cyclic groups that have been proposed in a number of conventional ArF resists. Examples thereof are the same as the aliphatic cyclic groups mentioned in “Acid-dissociable groups containing formula groups”.

  Examples of the acetal type acid dissociable group also include a group represented by the following general formula (p2).

［式中、Ｒ^１７、Ｒ^１８はそれぞれ独立して直鎖状若しくは分岐鎖状のアルキル基または水素原子であり；Ｒ^１９は直鎖状、分岐鎖状若しくは環状のアルキル基である。または、Ｒ^１７およびＲ^１９がそれぞれ独立に直鎖状若しくは分岐鎖状のアルキレン基であって、Ｒ^１７とＲ^１９とが結合して環を形成していてもよい。］

[Wherein, R ¹⁷ and R ¹⁸ each independently represents a linear or branched alkyl group or a hydrogen atom; and R ¹⁹ represents a linear, branched or cyclic alkyl group. Alternatively, R ¹⁷ and R ¹⁹ may each independently be a linear or branched alkylene group, and R ¹⁷ and R ¹⁹ may be bonded to form a ring. ]

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
In particular, it is preferable that one of R ¹⁷ and R ¹⁸ is a hydrogen atom and the other is a methyl group.
R ¹⁹ is a linear, branched or cyclic alkyl group, preferably having 1 to 15 carbon atoms, and may be any of linear, branched or cyclic.
When R ¹⁹ is linear or branched, it preferably has 1 to 5 carbon atoms, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.
When R ¹⁹ is cyclic, it preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, one or more polycycloalkanes such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group. Examples similar to the above “aliphatic cyclic group”, such as a group in which a hydrogen atom is removed, can be exemplified. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
In the formula (p2), R ¹⁷ and R ¹⁹ are each independently a linear or branched alkylene group (preferably an alkylene group having 1 to 5 carbon atoms), and R ¹⁹ and R ¹⁷ And may be combined.
In this case, a cyclic group is formed by R ¹⁷ , R ¹⁹ , the oxygen atom to which R ¹⁹ is bonded, and the carbon atom to which the oxygen atom and R ¹⁷ are bonded. The cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

As the structural unit (c2), the same structural units as those described later (a1) can be used. The structural unit (c2) may or may not have a fluorine atom or a silicon atom. Examples of the structural unit (c2) having a fluorine atom or a silicon atom include those in which R ⁰ in the general formula (c-0) is an acid-decomposable group, and particularly in the formula (c-0). L ⁰¹ is ^{-C (= O) -O-L} 10 -, - C (= O) -N (R N) -L 10 - or ^-R ar ^{-L 10} - a is is preferable.
More specifically, examples of the structural unit (c2) include structural units represented by the following general formulas (c2-11) to (c2-15).

［式（ｃ２−１１）〜（ｃ２−１２）中、Ｒ、Ｌ^１１、Ｒ^ａｒ、Ｌ^１２、Ｒ^Ｎはそれぞれ前記と同じであり、Ｒ^０３は酸解離性基である。式（ｃ２−１３）中、Ｒ、Ｒ^ａｒ、Ｌ^１３、Ｒ^０３はそれぞれ前記と同じであり、ｚは０または１である。式（ｃ２−１４）〜（ｃ２−１５）中、Ｒ、Ｌ^１４、Ｒ^０３、Ｒ^Ｎ、ｚはそれぞれ前記と同じである。］

Wherein ^{(c2-11) ~ (c2-12),} R, L 11, R ar, L 12, R N are the same as defined ^{above, R 03} represents an acid dissociable group. In formula (c2-13), R, R ^ar , L ¹³ and R ⁰³ are the same as defined above, and z is 0 or 1. In formulas (c2-14) to (c2-15), R, L ¹⁴ , R ⁰³ , R ^N and z are the same as defined above. ]

Wherein ^{(c2-11) ~ (c2-15),} R, L 11 ~L 14, R ar, generally exemplified in the description of each of ^{R N} the structural unit (c1) expression (c1-11) ~ (c1 -15) in ^{R, L 11 ~L 14, R} ar, it is the same as ^{R N.} However, the structural units represented by formulas (c2-11) to (c2-15) do not necessarily have a fluorine atom or a silicon atom.
Examples of the acid dissociable group for R ⁰³ include the same groups as described above. Among these, a tertiary alkyl ester type acid dissociable group is preferable, and an acid dissociable group containing an aliphatic cyclic group is particularly preferable.

When the component (C) contains the structural unit (c2), the structural unit (c2) contained in the component (C) may be one type or two or more types.
In the component (C), the proportion of the structural unit (c2) is preferably from 0 to 45 mol%, more preferably from 5 to 40 mol%, more preferably from 10 to 40 mol%, based on all the structural units constituting the component (C). Is more preferable. By setting the upper limit value or less, it is possible to balance with other structural units. When the content is 5 mol% or more, the solubility of the developer in the exposed area is improved in the case of an alkali development process, and in the unexposed area in the case of a solvent development process.

[Structural unit (c3)]
The structural unit (c3) is a structural unit containing a polar group. When the component (C) has the structural unit (c3), the polarity of the component (C) after exposure is further improved. The improvement in polarity contributes to the reduction of defects. Further, in the case of an alkali development process, it contributes to an improvement in resolution and the like.
Examples of the polar group include —OH, —COOH, —CN, —SO ₂ NH ₂ , —CONH ₂ , and the like. -OH may be a phenolic hydroxyl group or an alcoholic hydroxyl group.
The structural unit (c3) is preferably a structural unit containing a hydrocarbon group in which a part of hydrogen atoms is substituted with a polar group or an organic group containing a polar group.
Examples of the organic group containing a polar group include a hydroxyalkyl group, a hydroxyalkyloxy group, a fluorinated alcohol group (a hydroxyalkyl group in which some or all of the hydrogen atoms bonded to a carbon atom are substituted with fluorine atoms), hydroxy An aryl group etc. are mentioned. Among these, the carbon skeleton of the hydroxyalkyl group, hydroxyalkyloxy group, and fluorinated alcohol group may be linear, branched or cyclic, or a combination thereof. When it is linear or branched, the carbon skeleton preferably has 1 to 12 carbon atoms. When it is cyclic, the carbon skeleton preferably has 3 to 30 carbon atoms. Examples of the aryl group in the hydroxyaryl group include groups obtained by removing one hydrogen atom from the aromatic ring mentioned in the description of the aromatic group, and a phenyl group or a naphthyl group is preferable.
The hydrocarbon group in which a hydrogen atom is substituted with a polar group or an organic group containing a polar group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Especially, it is more preferable that the hydrocarbon group in the structural unit (c3) is an aromatic hydrocarbon group.
Examples of the aliphatic hydrocarbon group and the aromatic hydrocarbon group in the hydrocarbon group include a divalent hydrocarbon group in the description of the divalent linking group in L ⁰¹ in the general formula (I-1). Examples of the aliphatic hydrocarbon group and aromatic hydrocarbon group are the same.
The hydrocarbon group may have a substituent other than a polar group. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).
The structural unit (c3) is preferably a structural unit derived from (α-substituted) acrylic acid or a structural unit derived from (α-substituted) acrylic acid ester and containing a polar group. The structural unit derived from (α-substituted) acrylic acid and the structural unit derived from (α-substituted) acrylic ester are each a single bond by cleavage of the ethylenic double bond of (α-substituted) acrylic acid. A structural unit having a structure in which an ethylenic double bond of an (α-substituted) acrylate ester is cleaved to form a single bond.
Examples of the structural unit derived from an (α-substituted) acrylate ester and containing a polar group include the structural unit (a3-11) described later.
The structural unit (c3) may or may not have a fluorine atom or a silicon atom. Examples of the structural unit (c3) having a fluorine atom or a silicon atom include those in which R ⁰ in the general formula (c-0) is a hydrocarbon group containing a polar group.
As the structural unit (c3), those containing a fluorine atom in addition to the polar group are preferable, and R ⁰ in the general formula (c-0) is an aromatic cyclic group having a hydroxyl group and a fluorine atom bonded thereto. Or an aliphatic cyclic group to which a fluorinated alcohol group is bonded is more preferable. In particular, L ^{01 in} formula (c-0) is preferably a single bond, —C (═O) —OL ¹⁰ — or —C (═O) —N (R ^N ) —L ¹⁰ —.
Specific examples of preferred structural units (c3) are shown below.

When the component (C) contains the structural unit (c3), the structural unit (c3) contained in the component (C) may be one type or two or more types.
In the component (C), the proportion of the structural unit (c3) is preferably from 0 to 50 mol%, more preferably from 5 to 45 mol%, based on all the structural units constituting the component (C). By setting the upper limit value or less, it is possible to balance with other structural units. By setting it to 5 mol% or more, the effect of containing the structural unit (c3) can be sufficiently obtained. When the structural unit (c3) has an aromatic group, the effect of reducing the influence of OoB light is further improved.

[Structural unit (c4)]
The structural unit (c4) is a fluorine-containing structural unit that includes a cyclic group and does not correspond to the structural units (c1) to (c3). By having the structural unit (c4), the surface segregation effect is enhanced.
The cyclic group included in the structural unit (c4) may be an aromatic cyclic group or an aliphatic cyclic group.
Examples of the aromatic cyclic group include those obtained by removing one or more hydrogen atoms from the aromatic ring mentioned in the description of the aromatic group. In the case of having an aromatic cyclic group, the effect of reducing the influence of OoB light is improved.
The aliphatic cyclic group may be saturated or unsaturated, and is usually preferably saturated. The aliphatic cyclic group may be monocyclic or polycyclic. As the monocyclic aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.
A substituent may be bonded to the cyclic group. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).
Among these, examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group include the same groups as those described as the substituent that may be bonded to the aromatic ring in the description of the aromatic group. .
Examples of the polar group as the substituent include a hydroxyl group, a carboxy group, an amino group, a sulfo group, a cyano group, a hydroxyalkyl group, a hydroxyalkyloxy group, a fluorinated alcohol group (a part of a hydrogen atom bonded to a carbon atom or And hydroxyalkyl groups all substituted with fluorine atoms). Among these, the carbon skeleton of the hydroxyalkyl group, hydroxyalkyloxy group, and fluorinated alcohol group may be linear, branched or cyclic, or a combination thereof. When it is linear or branched, the carbon skeleton preferably has 1 to 12 carbon atoms. When it is cyclic, the carbon skeleton preferably has 3 to 30 carbon atoms.
As the structural unit (c4), R ⁰ in the general formula (c-0) is preferably a fluorine-containing cyclic group, and particularly L ⁰¹ in the formula (c-0) is a single bond, —C ( ^{= O) -O-L 10 -} , or ^{-C (= O) -N (R} N) -L 10 - a is is preferable.
Specific examples of preferred structural units (c4) are shown below.

When the component (C) contains the structural unit (c4), the structural unit (c3) contained in the component (C) may be one type or two or more types.
In the component (C), the proportion of the structural unit (c4) is preferably from 0 to 30 mol%, more preferably from 1 to 20 mol%, based on all the structural units constituting the component (C). By setting the upper limit value or less, it is possible to balance with other structural units. If it is 1 mol% or more, the effect of containing the structural unit (c4) is sufficiently obtained.

[Structural unit (c5)]
The structural unit (c5) is a silicon-containing structural unit containing a trialkylsilyl group or an organic group having a siloxane bond.
Examples of the trialkylsilyl group include a group represented by —Si (R ⁷⁴ ) (R ⁷⁵ ) (R ⁷⁶ ). In the formula, R ^{74 to} R ⁷⁶ are each independently a linear or branched alkyl group. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and still more preferably 1 to 5. As the alkyl group, a methyl group, an ethyl group, an isopropyl group, a t-butyl group and the like are preferable, and a methyl group is particularly preferable.
Specific examples of the trialkylsilyl group include a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, and a t-butyldimethylsilyl group.
The organic group containing a trialkylsilyl group may be composed of only a trialkylsilyl group, wherein n (n is an integer of 1 or more) trialkylsilyl groups are bonded to a (n + 1) -valent linking group. There may be. Among the (n + 1) -valent linking groups, the linking group in the case where n is 1, that is, the divalent linking group is exemplified in the description of the divalent linking group of L ^{01 in} the general formula (I-1). And a linear or branched alkylene group into which an ether bond or an ester bond may be inserted is preferable. Examples of the linking group in the case where n is 2 or more include groups in which (n-1) hydrogen atoms are further removed from the linking group of the divalent linking group.
Examples of the organic group containing a siloxane bond (Si—O—Si) include a cyclic siloxane in which a hydrocarbon group is bonded to a silicon atom, a cage silsesquioxane in which a hydrocarbon group is bonded to a silicon atom, a chain or a cyclic structure. And a group in which a part of the carbon chain of the alkyl group is substituted with -Si-O-Si-. The hydrocarbon group bonded to the silicon atom of the cyclic siloxane or cage silsesquioxane may be an aliphatic hydrocarbon group or an aromatic group. Preferably it is an aliphatic group, More preferably, it is a C1-C5 alkyl group.
Examples of the structural unit (c5) include those in which R ⁰ in the general formula (c-0) is a trialkylsilyl group or an organic group containing a siloxane structure, and particularly L ⁰¹ in the formula (c-0). Are preferably —C (═O) —OL ¹⁰ — or a single bond.

When the component (C) contains the structural unit (c5), the structural unit (c5) contained in the component (C) may be one type or two or more types.
In the component (C), the proportion of the structural unit (c5) is preferably from 0 to 60 mol%, more preferably from 1 to 50 mol%, more preferably from 5 to 40 mol%, based on all structural units constituting the component (C). Is more preferable. By setting it as the above range, the surface segregation effect, the coating property, etc. can be improved and the balance with other structural units can be taken.

The component (C) may further have a structural unit other than the structural units (c1) to (c5) (hereinafter referred to as the structural unit (c6)).
The structural unit (c6) is not particularly limited as long as it can form a copolymer with the structural units (c1) to (c5). For example, a number of hitherto known materials can be used as resist resins for ArF excimer laser, KrF excimer laser, EB, EUV and the like. Examples of such a structural unit include structural units (a0), (a2), (a4) and the like mentioned in the description of the component (A) described later, and can be appropriately selected from these.

(C) The structural unit which comprises a component may be 1 type, or 2 or more types.
When the structural unit constituting the component (C) is one kind, the structural unit includes a fluorine atom or a silicon atom and a base-decomposable polar conversion group, specifically, the structural unit (c1). Is used.

In the component (C), the proportion of the structural unit containing at least one kind (preferably a fluorine atom) selected from a fluorine atom and a silicon atom is the proportion of all the structural units constituting the component (C) in terms of the effect of the present invention. 70 mol% or more is preferable with respect to the total, and 80 mol% or more is more preferable. An upper limit is not specifically limited, 100 mol% may be sufficient.
In the component (C), the preferred ratio of the structural unit having a polar conversion group that is decomposed by the action of a base to increase the polarity is the same as the preferred ratio of the structural unit (c1).

The component (C) is preferably a polymer having the structural unit (c1), and a copolymer having the structural unit (c1) and at least one selected from the structural unit (c2) and the structural unit (c3). It is preferably a coalescence.
The structural unit (c1) is at least one selected from the group consisting of structural units represented by the general formulas (c1-11) to (c1-15) and (c1-21) to (c1-25). Preferably, at least one selected from the group consisting of structural units represented by general formula (c1-11), (c1-14), or (c1-23) is more preferable.
As the structural unit (c2), a structural unit (a11) described later is preferable, (a1-0-1) is more preferable, and (a1-1-32) is more preferable.
As the structural unit (c3), a structural unit derived from (α-substituted) acrylic acid, a structural unit having an aromatic cyclic group to which a fluorine atom and a hydroxyl group are bonded, or a structure having an aromatic cyclic group to which a hydroxyl group is bonded Preferred is a unit or a structural unit having an aliphatic cyclic group to which a fluorinated alcohol group is bonded, and more preferably a hydroxyphenyl group in which a hydrogen atom is substituted with a fluorine atom or a cyclohexyl group to which a fluorinated alcohol group is bonded. preferable.

The mass average molecular weight (Mw) of the component (C) (polystyrene conversion standard by gel permeation chromatography (GPC)) is not particularly limited, preferably 1000 to 80000, more preferably 5000 to 60000, and more preferably 10,000 to 50000 is most preferred. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
The dispersity (Mw / Mn) is not particularly limited, but is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5. In addition, Mn shows a number average molecular weight.

The component (C) can be obtained by polymerizing a monomer that induces a constituent unit to be contained, for example, by known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). .
In addition, the component (C) is used in combination with a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH at the time of the polymerization. A —C (CF ₃ ) ₂ —OH group may be introduced into the. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing
The monomer for deriving each structural unit can be synthesized by a known method. For example, the monomer corresponding to the structural unit (a0) can be synthesized by a method disclosed in JP-A-2006-045311, JP-A-2010-095643, or the like. About a well-known monomer, a commercially available thing can also be used.

As the component (C), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present invention, the content of the component (C) is 1 to 15 parts by mass with respect to 100 parts by mass of the component (A), preferably 2 to 14 parts by mass, and 3 to 12 parts by mass. More preferred. When the amount is 1 part by mass or more, the effect of improving the pattern shape, limit resolution performance, and the like of a resist pattern formed by EUV exposure or EB exposure is excellent. When it is 15 parts by mass or less, the balance with the component (A) is good, and the lithography properties such as shape and resolution are good.

<(A) component>
The component (A) used in the resist composition of the present invention is a base material component that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid.
Component (A) may have increased solubility in a developer due to the action of an acid, or may decrease solubility in a developer due to the action of an acid.
The component (A) may contain a site that generates an acid upon exposure (acid generating site) in the side chain or at the end of the main chain. When the side chain has an acid generation site, it has a structural unit (a0) described later.

When the resist composition of the present invention is a resist composition that forms a negative resist pattern in an alkali development process (or forms a positive resist pattern in a solvent development process), the component (A) is preferably A base material component (hereinafter also referred to as component (A-2)) that generates an acid upon exposure and is soluble in an alkaline developer is used, and a crosslinking agent component is further blended. In such a resist composition, when an acid is generated from the component (A-2) by exposure, the acid acts to cause crosslinking between the component (A-2) and the crosslinking agent component. Solubility decreases (solubility in organic developer increases). Therefore, in the formation of a resist pattern, when a resist film obtained by coating the resist composition on a support is selectively exposed, the exposed portion is hardly soluble in an alkali developer (to an organic developer). On the other hand, the unexposed area remains soluble (almost insoluble in the organic developer) while remaining undissolved in the alkali developer, so that a negative resist pattern can be formed by developing with an alkali developer. . At this time, if an organic developer is used as the developer, a positive resist pattern can be formed.
As the component (A-2), an acid generating site that generates an acid upon exposure (for example, an acid generated by the above-described exposure) is added to a resin that is soluble in an alkali developer (hereinafter referred to as “alkali-soluble resin”). And an anion portion that is generated).
Examples of the alkali-soluble resin (before introduction of the acid generation site) include α- (hydroxyalkyl) acrylic acid or alkyl of α- (hydroxyalkyl) acrylic acid disclosed in JP-A-2000-206694. A resin having a unit derived from at least one selected from an ester (preferably an alkyl ester having 1 to 5 carbon atoms); disclosed in US Pat. No. 6,949,325, on the α-position carbon atom having a sulfonamide group An acrylic resin or a polycycloolefin resin to which an atom other than a hydrogen atom or a substituent may be bonded; disclosed in US Pat. Contains fluorinated alcohols, and atoms other than hydrogen atoms or carbon atoms at the α-position Have substituents attached also good acrylic resin; disclosed in Japanese 2006-259582 discloses, polycycloolefin resins having fluorinated alcohol, with minimal swelling can formation of a satisfactory resist pattern.
In addition, the α- (hydroxyalkyl) acrylic acid is an α-position carbon atom to which a carboxy group is bonded among acrylic acids in which an atom other than a hydrogen atom or a substituent may be bonded to the α-position carbon atom. One or both of acrylic acid to which a hydrogen atom is bonded and α-hydroxyalkyl acrylic acid in which a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) is bonded to the α-position carbon atom Show.
As the acid generation site, one having the same structure as the acid generation site of a known compound as an acid generator for the resist composition can be applied.
The introduction position of the acid generation site may be the main chain end or the side chain portion. The introduction of the acid generating site to the main chain end can be carried out by using, for example, a polymerization initiator having an acid generating site as a polymerization initiator when producing an alkali-soluble resin. When the alkali-soluble resin is produced, the introduction into the side chain moiety is performed by using an alkali-soluble group such as a hydroxyl group or a carboxy group as a polar group in a monomer having an alkali-soluble group (for example, a constituent unit (a3) described later). Monomer having an acid generating site (for example, a single unit for inducing a structural unit (a0) to be described later) and a precursor thereof (for example, an alkali-soluble group protected with a protecting group) or a precursor thereof. The polymer can be polymerized.
As the crosslinking agent component, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group, a melamine crosslinking agent, or the like because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent component is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

When the resist composition of the present invention is a resist composition that forms a positive resist pattern in an alkali development process and a negative resist pattern in a solvent development process, the component (A) is preferably an acid A base material component (hereinafter sometimes referred to as (A-1) component) whose polarity is increased by action is used. Since the polarity of the component (A-1) changes before and after exposure, by using the component (A-1), a good development contrast can be obtained not only in the alkali development process but also in the solvent development process.
That is, when the alkali development process is applied, the component (A-1) is hardly soluble in an alkali developer before exposure, and when acid is generated from the component (A-1) by exposure, the action of the acid This increases the polarity and increases the solubility in an alkaline developer. Therefore, in the formation of a resist pattern, when a resist film obtained by applying the resist composition on a support is selectively exposed, the exposed portion changes from slightly soluble to soluble in an alkaline developer. Since the unexposed portion remains hardly soluble in alkali and does not change, a positive resist pattern can be formed by alkali development. On the other hand, when the solvent development process is applied, the component (A-1) is highly soluble in an organic developer before exposure, and when acid is generated from the component (A-1) by exposure, Due to the action, the polarity becomes higher and the solubility in an organic developer decreases. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition on the support is selectively exposed, the exposed portion changes from soluble to poorly soluble in an organic developer. On the other hand, since the unexposed portion remains soluble and does not change, by developing with an organic developer, a contrast can be provided between the exposed portion and the unexposed portion, and a negative resist pattern can be formed.
In the present invention, the component (A) is preferably the component (A-1).

[Polymer Compound (A1)]
(A) component contains the high molecular compound (A1) (henceforth (A1) component) which has the structural unit (a0) containing group represented by the following general formula (a0-1) or (a0-2). To do.
The structural unit (a0) has a group represented by the following general formula (a0-1) or (a0-2) to generate an acid upon exposure.

［式中、Ｑ^１及びＱ^２はそれぞれ独立に単結合又は２価の連結基である。Ｒ^３、Ｒ^４及びＲ^５はそれぞれ独立に有機基であり、Ｒ^４とＲ^５とは相互に結合して式中のイオウ原子と共に環を形成してもよい。ただし、式中の基−Ｒ^３−Ｓ^＋（Ｒ^４）（Ｒ^５）は、全体で芳香環を１個のみ有するか又は芳香環を有さない。Ｖ⁻は対アニオンである。Ａ⁻はアニオンを含む有機基である。Ｍ^ｍ＋はｍ価の有機カチオンであり、ｍは１〜３の整数である。ただし、Ｍ^ｍ＋は、芳香環を１個のみ有するか、又は芳香環を有さない。］

[Wherein, Q ¹ and Q ² are each independently a single bond or a divalent linking group. R ³ , R ⁴ and R ⁵ are each independently an organic group, and R ⁴ and R ⁵ may be bonded to each other to form a ring together with the sulfur atom in the formula. However, group -R ^{< 3 >} -S ^<+> (R ^{< 4 >} ) (R ^{< 5 >} ) in a formula has only one aromatic ring as a whole, or does not have an aromatic ring. V ⁻ is a counter anion. A ^- is an organic group containing anion. M ^{m +} is an m-valent organic cation, and m is an integer of 1 to 3. However, M ^{m +} has only one aromatic ring or no aromatic ring. ]

(Structural unit (a0))
(Structural unit having a group represented by the formula (a0-1))
In formula (a0-1), Q ¹ represents a single bond or a divalent linking group.
Examples of the divalent linking group for Q ¹ include the same divalent linking groups as those described above for L ⁰¹ in formula (I-1). Among these, Q ¹ in the present invention is preferably a single bond, an ester bond [—C (═O) —O—], an ether bond (—O—), an alkylene group, or a combination thereof.
Also, if Q ¹ is an aromatic ring, it is preferred that the aromatic ring is only one in the entire Q ^1. When Q ¹ has an aromatic ring, R ³ , R ⁴ and R ⁵ preferably have no aromatic ring.

In formula (a0-1), R ³ , R ⁴ and R ⁵ are each independently an organic group, and R ⁴ and R ⁵ may be bonded to each other to form a ring together with the sulfur atom in the formula. .
The organic groups of R ³ , R ⁴ and R ⁵ are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.)) Etc.).
Examples of the organic group include hydrocarbon groups in which some or all of the hydrogen atoms may be substituted with a substituent, and a linking group may be inserted between carbon atoms. Examples of the linking group include those similar to the divalent linking group containing a hetero atom. The organic group may or may not have an aromatic ring.
However, group -R ^{< 3 >} -S ^<+> (R ^{< 4 >} ) (R ^{< 5 >} ) in a formula has only one aromatic ring as a whole, or does not have an aromatic ring. That is, when R ⁴ and R ⁵ are not bonded to each other to form a ring with the sulfur atom in the formula, only one of R ³ , R ⁴ and R ⁵ has one aromatic ring. The other two are organic groups that do not have an aromatic ring, or all of R ³ , R ^4, and R ⁵ are organic groups that do not have an aromatic ring. When R ⁴ and R ⁵ are bonded to each other to form one aromatic ring together with the sulfur atom in the formula, R ³ is an organic group having no aromatic ring. When R ⁴ and R ⁵ are bonded to each other to form a ring with the sulfur atom in the formula, and the ring is an aliphatic ring (ring having no aromaticity), R ³ is an organic group having one aromatic ring or an organic group having no aromatic ring. When the ring formed by combining R ⁴ and R ⁵ together with the sulfur atom in the formula is a ring containing two or more aromatic rings, the structural unit corresponds to the structural unit (a0-1). do not do.
The aromatic ring absorbs OoB light having a DUV wavelength. The number of aromatic rings in the whole group -R ³ -S ⁺ (R ⁴ ) (R ⁵ ) composed of S ⁺ and R ³ , R ⁴ and R ⁵ directly bonded thereto is 1 or less. Thus, the influence of OoB light can be suppressed.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and examples thereof include the same aromatic rings as mentioned in the description of the divalent hydrocarbon group. Specific examples include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; and the like. . Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
A substituent may be bonded to the aromatic ring. Examples of the substituent include the same substituents as those described as the substituent that the aromatic hydrocarbon group may have in the description of the divalent hydrocarbon group.

Specific examples of the organic group for R ³ include an alkylene group which may have a substituent and an arylene group which may have a substituent. Among these, an alkylene group which may have a substituent is preferable.
Examples of the alkylene group which may have a substituent in R ³ include an unsubstituted alkylene group, a substituted alkylene group in which part or all of the hydrogen atoms of the unsubstituted alkylene group are substituted with a substituent, and the like. Is mentioned.
The unsubstituted alkylene group may be linear, branched or cyclic. From the viewpoint of excellent resolution, an alkylene group having 1 to 10 carbon atoms is preferable, and an alkylene group having 1 to 5 carbon atoms is more preferable. Specifically, methylene group, ethylene group, n-propylene group, isopropylene group, n-butylene group, isobutylene group, n-pentylene group, cyclopentylene group, hexylene group, cyclohexylene group, nonylene group, decylene group. Etc.

Examples of the substituent that the substituted alkylene group has include a halogen atom, an oxo group (═O), a cyano group, an alkyl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, —C (═O) —O—R ⁷ ″, ^{-O-C (= O) -R} 8 ", -O-R 9", an aryl group ^.R 7 ^", R ^8", the ^{R 9} "are each independently, a hydrogen atom or a hydrocarbon group is there.
Among these, examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom, and a fluorine atom is preferable.

The alkyl group as a substituent in the substituted alkylene group may be linear, branched or cyclic. The carbon number is preferably 1-30.
Among them, the linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.
The cyclic alkyl group may be monocyclic or polycyclic. The number of carbon atoms is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. Specifically, for example, a group in which one or more hydrogen atoms are removed from a monocycloalkane; a group in which one or more hydrogen atoms are removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.
The cyclic alkyl group is preferably a polycyclic group, preferably a group obtained by removing one or more hydrogen atoms from polycycloalkane, and most preferably a group obtained by removing one or more hydrogen atoms from adamantane.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.

Examples of the alkoxyalkyloxy group as a substituent in the substituted alkylene group include:
General formula: -O-C ( ^R47 ) ( ^R48 ) -O- ^R49
[Wherein, R ⁴⁷ and R ⁴⁸ each independently represent a hydrogen atom or a linear or branched alkyl group, and R ⁴⁹ represents an alkyl group. ]
The group represented by these is mentioned.
In R ⁴⁷ and R ⁴⁸ , the alkyl group preferably has 1 to 5 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
At least one of R ⁴⁷ and R ⁴⁸ is preferably a hydrogen atom. In particular, it is more preferable that one is a hydrogen atom and the other is a hydrogen atom or a methyl group.
The alkyl group for R ⁴⁹ preferably has 1 to 15 carbon atoms and may be linear, branched or cyclic.
The linear or branched alkyl group for R ⁴⁹ preferably has 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. Can be mentioned.
The cyclic alkyl group for R ⁴⁹ preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, etc., which may or may not be substituted with an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group, etc. And a group obtained by removing one or more hydrogen atoms from the polycycloalkane. Examples of the monocycloalkane include cyclopentane and cyclohexane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.

Examples of the alkoxycarbonylalkyloxy group as a substituent in the substituted alkylene group include:
General formula: —O—R ⁵⁰ —C (═O) —O—R ⁵⁶
[Wherein, R ⁵⁰ represents a linear or branched alkylene group, and R ⁵⁶ represents a tertiary alkyl group. ]
The group represented by these is mentioned.
The linear or branched alkylene group for R ⁵⁰ preferably has 1 to 5 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, or a 1,1-dimethylethylene group. Etc.
The tertiary alkyl group for R ⁵⁶ includes a 2-methyl-2-adamantyl group, a 2- (2-propyl) -2-adamantyl group, a 2-ethyl-2-adamantyl group, and a 1-methyl-1-cyclopentyl group. 1-ethyl-1-cyclopentyl group, 1-methyl-1-cyclohexyl group, 1-ethyl-1-cyclohexyl group, 1- (1-adamantyl) -1-methylethyl group, 1- (1-adamantyl)- 1-methylpropyl group, 1- (1-adamantyl) -1-methylbutyl group, 1- (1-adamantyl) -1-methylpentyl group; 1- (1-cyclopentyl) -1-methylethyl group, 1- ( 1-cyclopentyl) -1-methylpropyl group, 1- (1-cyclopentyl) -1-methylbutyl group, 1- (1-cyclopentyl) -1-methylpentyl group; 1- (1-cyclohexyl) -1-methylethyl group, 1- (1-cyclohexyl) -1-methylpropyl group, 1- (1-cyclohexyl) -1-methylbutyl group, 1- (1-cyclohexyl) -1 -Methylpentyl group, tert-butyl group, tert-pentyl group, tert-hexyl group and the like can be mentioned.

Moreover, the general ^formula: the ^{R 56} in the -O-R 50 -C (= O ) -O-R 56, also include groups replaced by ^{R 56} '. R ⁵⁶ ′ is a hydrogen atom, an alkyl group, a fluorinated alkyl group, or an aliphatic cyclic group that may contain a hetero atom.
^Examples of the alkyl group for R ⁵⁶ ′ include the same alkyl groups as those described above for R ⁴⁹ .
^Examples of the fluorinated alkyl group for R ⁵⁶ ′ include groups in which some or all of the hydrogen atoms within the alkyl group for R ⁴⁹ have been substituted with fluorine atoms.
Examples of the aliphatic cyclic group which may contain a hetero atom in R ⁵⁶ ′ include an aliphatic cyclic group containing no hetero atom, an aliphatic cyclic group containing a hetero atom in the ring structure, and an aliphatic cyclic group. Examples include those in which a hydrogen atom in the group is substituted with a heteroatom.
Regarding R ⁵⁶ ′, the aliphatic cyclic group containing no hetero atom includes a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, and the like. Can be mentioned. Examples of the monocycloalkane include cyclopentane and cyclohexane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
Regarding R ⁵⁶ ′, specific examples of the aliphatic cyclic group containing a hetero atom in the ring structure include groups represented by formulas (L1) to (L5) and (S1) to (S4) described later. It is done.
As for R ⁵⁶ ′, the hydrogen atom in the aliphatic cyclic group is specifically substituted with a hetero atom, specifically, the hydrogen atom in the aliphatic cyclic group is substituted with an oxo group (═O), etc. Is mentioned.
As for R ⁵⁶ ′, the hydrogen atom in the aliphatic cyclic group is specifically substituted with a hetero atom, specifically, the hydrogen atom in the aliphatic cyclic group is substituted with an oxo group (═O), etc. Is mentioned.

R ⁷ ″ in —C (═O) —O—R ⁷ ″ represents a hydrogen atom or a hydrocarbon group.
The hydrocarbon group for R ⁷ ″ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be a saturated hydrocarbon group or an aliphatic unsaturated hydrocarbon group. Any of these may be used.

The saturated hydrocarbon group for R ⁷ ″ may be linear, branched or cyclic, or a combination thereof.
1-25 are preferable, as for carbon number of a linear or branched saturated hydrocarbon group, 1-15 are more preferable, and 4-10 are more preferable.
Examples of the linear saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group.
The branched saturated hydrocarbon radicals, for example, tertiary alkyl groups mentioned in the description of the R ^56. Examples of branched saturated hydrocarbon groups other than tertiary alkyl groups include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3 -Methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like can be mentioned.
The linear or branched saturated hydrocarbon group may have a substituent. Examples of the substituent include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (═O), a cyano group, and a carboxy group.
As the alkoxy group as a substituent of the linear or branched saturated hydrocarbon group, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, An n-butoxy group and a tert-butoxy group are preferable, and a methoxy group and an ethoxy group are most preferable.
Examples of the halogen atom as a substituent of the linear or branched saturated hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
As the halogenated alkyl group as a substituent of the linear or branched saturated hydrocarbon group, part or all of the hydrogen atoms of the linear or branched saturated hydrocarbon group are the halogen atoms. And a group substituted with.
The number of carbon atoms of the cyclic saturated hydrocarbon group in R ⁷ ″ is preferably 3 to 20. The cyclic saturated hydrocarbon group may be either a polycyclic group or a monocyclic group. A group in which one hydrogen atom is removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. More specifically, cyclopentane, cyclohexane, Examples thereof include monocycloalkanes such as cycloheptane and cyclooctane, and groups obtained by removing one hydrogen atom from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic saturated hydrocarbon group may have a substituent. For example, part of the carbon atoms constituting the ring of the cyclic alkyl group may be substituted with a heteroatom, or the hydrogen atom bonded to the ring of the cyclic alkyl group may be substituted with a substituent. Good.
Examples of the former include one or more hydrogen atoms from a heterocycloalkane in which a part of the carbon atoms constituting the ring of the monocycloalkane or polycycloalkane is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Examples include groups other than atoms. The ring structure may have an ester bond (—C (═O) —O—). Specifically, a lactone-containing monocyclic group such as a group obtained by removing one hydrogen atom from γ-butyrolactone, or a group obtained by removing one hydrogen atom from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring. And other lactone-containing polycyclic groups.
Examples of the substituent in the latter example include the same as those described above as the substituent that the linear or branched alkyl group may have, an alkyl group having 1 to 5 carbon atoms, and the like. .
The saturated hydrocarbon group for R ⁷ ″ may be a combination of a linear or branched saturated hydrocarbon group and a cyclic saturated hydrocarbon group.
As a combination of a linear or branched saturated hydrocarbon group and a cyclic saturated hydrocarbon group, a cyclic saturated hydrocarbon group as a substituent is bonded to the linear or branched saturated hydrocarbon group. Examples include a group (for example, 1- (1-adamantyl) methyl group), a group in which a linear or branched saturated hydrocarbon group is bonded to a cyclic saturated hydrocarbon group as a substituent.

The aliphatic unsaturated hydrocarbon group for R ⁷ ″ is preferably linear or branched. Examples of the linear aliphatic unsaturated hydrocarbon group include a vinyl group, a propenyl group (allyl group), and butynyl. Examples of the branched aliphatic unsaturated hydrocarbon group include 1-methylpropenyl group, 2-methylpropenyl group, etc. These linear or branched aliphatic unsaturated groups. The saturated hydrocarbon group may have a substituent, and examples of the substituent are the same as those exemplified as the substituent which the linear or branched alkyl group may have. Can be mentioned.

The aromatic hydrocarbon group for R ⁷ ″ is a monovalent hydrocarbon group having at least one aromatic ring and may have a substituent.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are more preferable, and 6-12 are especially preferable. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms; etc. Is mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); the aromatic hydrocarbon ring or aromatic heterocycle Groups in which one of the ring hydrogen atoms is substituted with an alkylene group (for example, arylalkyl such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.) Group, heteroarylalkyl group); and the like. The number of carbon atoms of the alkylene group that replaces the hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1. .
The aromatic hydrocarbon group may or may not have a substituent. However, in the present invention, since R ³ , R ⁴ and R ^{5 as a} whole have one or less aromatic ring, the substituent in the substituted alkylene group is —C (═O) —O—R ⁷ ″, and R ^{When 7} ″ is an aromatic hydrocarbon group, the substituent that the aromatic hydrocarbon group has is a non-aromatic substituent. “Non-aromatic” indicates no aromaticity. The non-aromatic substituent is not particularly limited as long as it does not contain an aromatic group (such as an aromatic hydrocarbon group) in the structure. For example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, An oxo group (= O) etc. are mentioned.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

Among the above, R ⁷ ″ is preferably a hydrogen atom, a saturated hydrocarbon group or an aliphatic unsaturated hydrocarbon group because of excellent lithography characteristics and resist pattern shape, and is preferably a hydrogen atom, a carbon number of 1 to 15 Are more preferably a linear or branched saturated hydrocarbon group or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms.

R ⁸ ″ in —O—C (═O) —R ⁸ ″ represents a hydrogen atom or a hydrocarbon group.
As R ⁸ ″, the same as R ⁷ ″ can be mentioned. Among them, a hydrogen atom, a saturated hydrocarbon group or an aliphatic unsaturated hydrocarbon group is preferable because of excellent lithography characteristics and resist pattern shape, and a hydrogen atom, a linear or branched group having 1 to 15 carbon atoms. A chain-like saturated hydrocarbon group or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms is more preferable.

^{"R 9} in" ^{-O-R 9} is hydrogen atom or a hydrocarbon group.
Examples of R ⁹ ″ include the same as R ⁷ ″. Among them, a hydrogen atom, a saturated hydrocarbon group or an aliphatic unsaturated hydrocarbon group is preferable because of excellent lithography characteristics and resist pattern shape, and a hydrogen atom, a linear or branched group having 1 to 15 carbon atoms. A chain-like saturated hydrocarbon group or a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms is more preferable.
The —O—R ⁹ ″ as the non-aromatic substituent is preferably a hydroxyl group or an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, or n-butoxy. Most preferably, it is a tert-butoxy group.

The aryl group as a substituent in the substituted alkylene group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group. However, in the present invention, since R ³ , R ⁴ and R ^{5 as a} whole have one or less aromatic rings, when R ³ is a substituted alkylene group and the substituted alkylene group has an aryl group as a substituent, The number of aryl groups that can be present as the substituent is one.
The aryl group as the substituent may have a substituent. However, in the present invention, since the total number of aromatic rings in R ³ , R ⁴ and R ⁵ is 1 or less, the substituent that the aryl group as the substituent has is a non-aromatic substituent. The non-aromatic substituent is not particularly limited as long as it does not contain an aromatic group (aromatic hydrocarbon group or the like) in the structure. For example, the aromatic hydrocarbon group in R ⁷ ″ may have. The thing similar to what was mentioned as a non-aromatic substituent is mentioned.

In the formula (a0-1), as the arylene group which may have a substituent for R ^3, an unsubstituted arylene group having 6 to 20 carbon atoms; a part of hydrogen atoms of the unsubstituted arylene group or Examples thereof include a substituted arylene group which is entirely substituted with a substituent.
The unsubstituted arylene group is preferably an arylene group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenylene group and a naphthylene group.
Examples of the substituent in the substituted arylene group include the same groups as those described above as the substituent in the substituted alkylene group. However, in the present invention, since R ³ , R ⁴ and R ^{5 as a} whole have one aromatic ring or less, when R ³ is a substituted arylene group, the substituent of the substituted arylene group is non-aromatic. It is a substituent. The non-aromatic substituent may be any as long as it does not contain an aromatic group (such as an aromatic hydrocarbon group) in the structure. Specifically, among those listed as the substituent in the substituted alkylene group, a halogen atom, an oxo group (═O), a cyano group, an alkyl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, —C (═O ) —O—R ⁷ ″, —O—C (═O) —R ⁸ ″, —O—R ⁹ ″ (where R ⁷ ″, R ⁸ ″, R ⁹ ″ are independently hydrogen atom, saturated carbonization) A hydrogen group or an aliphatic unsaturated hydrocarbon group).

In formula (a0-1), the organic groups of R ⁴ and R ⁵ are not particularly limited, but may be an aryl group which may have a substituent, or an alkyl which may have a substituent. And an alkenyl group optionally having a substituent. Among these, an alkyl group which may have a substituent is preferable.

Examples of the aryl group which may have a substituent in R ⁴ and R ⁵ include an unsubstituted aryl group having 6 to 20 carbon atoms; a part or all of the hydrogen atoms of the unsubstituted aryl group are substituent groups. Examples include substituted aryl groups.
The unsubstituted aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.
Examples of the substituent in the substituted aryl group include non-aromatic substituents. Examples of the non-aromatic substituent include the same non-aromatic substituents listed as the substituent that the substituted arylene group may have.

Examples of the alkyl group for R ⁴ and R ⁵ include an unsubstituted alkyl group, a substituted alkyl group in which part or all of the hydrogen atoms of the unsubstituted alkyl group are substituted with a substituent, and the like.
The unsubstituted alkyl group may be linear, branched or cyclic. From the point which is excellent in resolution, a C1-C10 alkyl group is preferable and a C1-C5 alkyl group is more preferable. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decyl group. .
Examples of the substituent in the substituted alkyl group include the same as those described as the substituent that the substituted alkylene group in R ³ may have.

Examples of the alkenyl group for R ⁴ and R ⁵ include an unsubstituted alkenyl group and a substituted alkenyl group in which part or all of the hydrogen atoms of the unsubstituted alkenyl group are substituted with a substituent.
The unsubstituted alkenyl group is preferably linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, and still more preferably 2 to 4. Specific examples include a vinyl group, a propenyl group (allyl group), a butynyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group.
Examples of the substituent in the substituted alkenyl group include the same groups as those described above as the substituent that the substituted alkylene group in R ³ may have.

In formula (a0-1), R ⁴ and R ⁵ may be bonded to each other to form a ring together with the sulfur atom in the formula. The ring may be saturated or unsaturated. The ring may be monocyclic or polycyclic. For example, when one or both of R ⁴ and R ⁵ forming a ring is a cyclic group (cyclic alkyl group or aryl group), a polycyclic ring (fused ring) is formed by combining them. The
As the ring to be formed, one ring containing a sulfur atom in the ring skeleton in the formula is preferably a 3- to 10-membered ring, particularly a 5- to 7-membered ring, including the sulfur atom. preferable.
The ring may have a hetero atom other than the sulfur atom to which R ⁴ and R ⁵ are bonded as an atom constituting the ring skeleton. Examples of the hetero atom include a sulfur atom, an oxygen atom, and a nitrogen atom.
Specific examples of the ring to be formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring, and the like.

In the present invention, —R ³ —S ⁺ (R ⁴ ) (R ⁵ ) has only one aromatic ring as a whole or no aromatic ring. Especially, it is preferable that all of R ³ , R ⁴ and R ⁵ do not have an aromatic ring, or only R ³ has an aromatic ring. -R ³ -S ⁺ (R ⁴ ) (R ⁵ ) has no aromatic ring or has only one aromatic ring as a whole, so that it has low sensitivity to DUV which is OoB light, and has no effect on EUV On the other hand, it can be a highly sensitive acid generating group.

In formula (a0-1), V ⁻ represents a counter anion.
The counter anion of V ⁻ is not particularly limited, and for example, those conventionally known as the anion part of the onium salt acid generator can be used as appropriate.
As V ⁻ , for example, the general formula “R ⁴ ” SO ₃ ^— (R ⁴ ”represents a linear, branched or cyclic alkyl group, halogenated alkyl group, aryl which may have a substituent. An anion represented by a group or an alkenyl group.

In the general formula “R ⁴ ″ SO ₃ ⁻ ”, R ⁴ ″ represents a linear, branched or cyclic alkyl group, halogenated alkyl group, aryl group, or alkenyl which may have a substituent. Represents a group.

The linear or branched alkyl group as R ⁴ ″ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and 1 to 4 carbon atoms. Most preferred.
The cyclic alkyl group as R ⁴ ″ preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms.
Examples of “R ⁴ ″ SO ₃ ⁻ ” when R ⁴ ″ is an alkyl group include methane sulfonate, n-propane sulfonate, n-butane sulfonate, n-octane sulfonate, 1-adamantane sulfonate, 2-norbornane sulfonate, Examples thereof include alkyl sulfonates such as d-camphor-10-sulfonate.

The halogenated alkyl group as R ⁴ ″ is one in which part or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms, and the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, Among them, a linear or branched alkyl group is more preferable, and it is a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, a tert-pentyl group, or an isopentyl group. More preferable examples of the halogen atom substituted with a hydrogen atom include a fluorine atom, a chlorine atom, an iodine atom, a bromine atom, etc. In a halogenated alkyl group, a hydrogen atom of an alkyl group (an alkyl group before halogenation) It is preferable that 50 to 100% of all the hydrogen atoms are substituted with halogen atoms, and all the hydrogen atoms are substituted with halogen atoms. It is more preferable to have.
Here, the halogenated alkyl group is preferably a fluorinated alkyl group. The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
Further, the fluorination rate of the fluorinated alkyl group is preferably 10 to 100%, more preferably 50 to 100%. Particularly, when all the hydrogen atoms are substituted with fluorine atoms, the strength of the acid is increased. preferable.
Specific examples of such a preferred fluorinated alkyl group include a trifluoromethyl group, a heptafluoro-n-propyl group, and a nonafluoro-n-butyl group.

The aryl group as R ⁴ ″ is preferably an aryl group having 6 to 20 carbon atoms.
The alkenyl group as R ⁴ ″ is preferably an alkenyl group having 2 to 10 carbon atoms.

In the above R ⁴ ″, “optionally substituted” means one of hydrogen atoms in the linear, branched or cyclic alkyl group, halogenated alkyl group, aryl group, or alkenyl group. It means that part or all may be substituted with a substituent (an atom or group other than a hydrogen atom).
The number of substituents in R ⁴ ″ may be one or two or more.

Examples of the substituent include a halogen atom, a hetero atom, an alkyl group, and a formula: X ³ -Q ^′ -[where Q ^′ is a divalent linking group containing an oxygen atom, and X ³ represents a substituent. It is a C3-C30 hydrocarbon group which may have. ] Etc. which are represented by these.
Examples of the halogen atom and alkyl group include the same groups as those described as the halogen atom and alkyl group in the halogenated alkyl group in R ⁴ ″.
Examples of the hetero atom include an oxygen atom, a nitrogen atom, and a sulfur atom.

X ³ -Q ^'- In the group represented by, ^Q' is a divalent linking group containing an oxygen atom.
Q ^′ may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: —O—), an ester bond (—C (═O) —O—), and an amide bond (—C (═O) —NH. -), A carbonyl group (-C (= O)-), a non-hydrocarbon oxygen atom-containing linking group such as a carbonate bond (-O-C (= O) -O-); the non-hydrocarbon oxygen atom Examples include a combination of a containing linking group and an alkylene group. A sulfonyl group (—SO ₂ —) may be further linked to the combination.
Examples of the combination include —R ⁹¹ —O—, —R ⁹² —O—C (═O) —, —C (═O) —O—R ⁹³ —O—C (═O) —, —SO _2- O—R ⁹⁴ —O—C (═O) —, —R ⁹⁵ —SO ₂ —O—R ⁹⁴ —O—C (═O) — (wherein R ^{91 to} R ⁹⁵ are each independently alkylene. Group.) And the like.
The alkylene group for R ^{91 to} R ⁹⁵ is preferably a linear or branched alkylene group, and the alkylene group preferably has 1 to 12 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably 1 to 3 carbon atoms. preferable.
Specific examples of the alkylene group include a methylene group [—CH ₂ —]; —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ) ₂ —, —C ( _{CH 3) (CH 2 CH 3} ) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as ethylene group _[-CH 2 CH _2— ]; —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —CH (CH ₂ CH ₃ ) CH ₂ — and the like. Alkylethylene groups; trimethylene groups (n-propylene groups) [—CH ₂ CH ₂ CH ₂ —]; alkyls such as —CH (CH ₃ ) CH ₂ CH ₂ — and —CH ₂ CH (CH ₃ ) CH ₂ — trimethylene; tetramethylene group _[-CH 2 _CH 2 C _{2 CH 2 -]; - CH} (CH 3) CH 2 CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 CH 2 - alkyl tetramethylene group and the like; pentamethylene group _[-CH 2 _CH 2 CH ₂ CH ₂ CH ₂ —] and the like.
Q ^′ is preferably a divalent linking group containing an ester bond or an ether bond, and in particular, —R ⁹¹ —O—, —R ⁹² —O—C (═O) — or —C (═O) — O—R ⁹³ —O—C (═O) — is preferred.

X ³ -Q ^'- In the group represented by the formula, the hydrocarbon group for X ³ may be an aromatic hydrocarbon group may be an aliphatic hydrocarbon group.
The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic.
The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and most preferably 6 to 12. However, the carbon number does not include the carbon number in the substituent. Specific examples of the aromatic hydrocarbon group include a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. Aryl groups such as aryl group, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc., from which one is removed. The number of carbon atoms in the alkyl chain in the arylalkyl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.
The aromatic hydrocarbon group may have a substituent. For example, a part of carbon atoms constituting the aromatic ring of the aromatic hydrocarbon group may be substituted with a hetero atom, and the hydrogen atom bonded to the aromatic ring of the aromatic hydrocarbon group is substituted with the substituent. May be.
Examples of the former include heteroaryl groups in which some of the carbon atoms constituting the ring of the aryl group are substituted with heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and aromatic hydrocarbons in the arylalkyl groups. Examples include heteroarylalkyl groups in which some of the carbon atoms constituting the ring are substituted with the above heteroatoms.
Examples of the substituent of the aromatic hydrocarbon group in the latter example include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
The alkyl group as a substituent of the aromatic hydrocarbon group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. preferable.
The alkoxy group as a substituent of the aromatic hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert- A butoxy group is preferable, and a methoxy group and an ethoxy group are most preferable.
Examples of the halogen atom as a substituent for the aromatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent of the aromatic hydrocarbon group include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
When X ³ has an aromatic ring, it is preferable that there is only one aromatic ring in the entire X ³ . In the case ^{where X 3} is an aromatic ^ring, R 3, ^{R 4} and ^{R 5} preferably has no aromatic ring.

The aliphatic hydrocarbon group for X ³ may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be linear, branched or cyclic.
In X ³ , the aliphatic hydrocarbon group may be a group in which a part of carbon atoms constituting the aliphatic hydrocarbon group may be substituted with a substituent containing a hetero atom, and hydrogen constituting the aliphatic hydrocarbon group A part or all of the atoms may be substituted with a substituent containing a hetero atom.
The “heteroatom” in X ³ is not particularly limited as long as it is an atom other than a carbon atom and a hydrogen atom, and examples thereof include a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom.
The substituent containing a hetero atom may be composed of only the hetero atom, or may be a group containing a group or atom other than the hetero atom.
Specific examples of the substituent for substituting a part of the carbon atom include —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O. —, —C (═O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), —S—, —S (═O) ₂ —, — S (= O) ₂ —O— and the like can be mentioned. When the aliphatic hydrocarbon group is cyclic, these substituents may be included in the ring structure.
Specific examples of the substituent for substituting part or all of the hydrogen atoms include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), and a cyano group.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group, and a methoxy group or an ethoxy group. Is most preferred.
As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.
As the halogenated alkyl group, a part or all of hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, etc. And a group substituted with a halogen atom.

Examples of the aliphatic hydrocarbon group include a linear or branched saturated hydrocarbon group, a linear or branched monovalent unsaturated hydrocarbon group, or a cyclic aliphatic hydrocarbon group (aliphatic ring). Formula group) is preferred.
The linear saturated hydrocarbon group (alkyl group) preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched saturated hydrocarbon group (alkyl group) preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

As an unsaturated hydrocarbon group, it is preferable that carbon number is 2-10, 2-5 are preferable, 2-4 are preferable, and 3 is especially preferable. Examples of the linear monovalent unsaturated hydrocarbon group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched monovalent unsaturated hydrocarbon group include a 1-methylpropenyl group and a 2-methylpropenyl group.
Among the above, the unsaturated hydrocarbon group is particularly preferably a propenyl group.

The aliphatic cyclic group may be a monocyclic group or a polycyclic group. The number of carbon atoms is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12.
Specifically, for example, a group in which one or more hydrogen atoms are removed from a monocycloalkane; a group in which one or more hydrogen atoms are removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.
When the aliphatic cyclic group does not contain a substituent containing a hetero atom in the ring structure, the aliphatic cyclic group is preferably a polycyclic group, and has one or more hydrogen atoms from the polycycloalkane. Excluded groups are preferred, and most preferred are groups in which one or more hydrogen atoms have been removed from adamantane.
When the aliphatic cyclic group includes a substituent containing a hetero atom in the ring structure, examples of the substituent containing a hetero atom include —O—, —C (═O) —O—, —S—. , —S (═O) ₂ — and —S (═O) ₂ —O— are preferable. Specific examples of the aliphatic cyclic group include the following formulas (L1) to (L6), (S1) to (S4), and the like.

［式中、Ｑ”は炭素数１〜５のアルキレン基、−Ｏ−、−Ｓ−、−Ｏ−Ｒ^９４’−または−Ｓ−Ｒ^９５’−であり、Ｒ^９４’およびＲ^９５’はそれぞれ独立に炭素数１〜５のアルキレン基であり、ｍは０または１の整数である。］

[Wherein Q ″ is an alkylene group having 1 to 5 carbon atoms, —O—, —S—, —O—R ^{94 ′} — or —S—R ^{95 ′} —, wherein R ^{94 ′} and R ^{95 ′} are Each independently represents an alkylene group having 1 to 5 carbon atoms, and m is an integer of 0 or 1.]

In the formula, examples of the alkylene group for Q ″, R ^{94 ′} and R ^{95 ′} include the same alkylene groups as those described above for R ^{91 to} R ⁹⁵ .
In these aliphatic cyclic groups, a part of hydrogen atoms bonded to carbon atoms constituting the ring structure may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
As said alkyl group, a C1-C5 alkyl group is preferable, and it is especially preferable that they are a methyl group, an ethyl group, a propyl group, n-butyl group, and a tert- butyl group.
Examples of the alkoxy group and the halogen atom are the same as those exemplified as the substituent for substituting part or all of the hydrogen atoms.

In the present invention, X ³ is preferably a cyclic group which may have a substituent. The cyclic group may be an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. It is preferably an aliphatic cyclic group that may be used.
The aromatic hydrocarbon group is preferably a naphthyl group which may have a substituent or a phenyl group which may have a substituent.
As the aliphatic cyclic group which may have a substituent, a polycyclic aliphatic cyclic group which may have a substituent is preferable. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from the polycycloalkane, the above (L2) to (L6), (S3) to (S4), and the like.

Among the above, the R ^{4 "is,} X ³ -Q ^'as a halogenated alkyl group or a substituted group, - it is preferable to have a.
^'- if having, as the ^{R 4 ", X 3 -Q'} -Y 3 - X 3 -Q as a substituent in the Formula, Q ^{'and X 3} are as defined above, the ^{Y 3} substituent A C1-C4 alkylene group which may have or a C1-C4 fluorinated alkylene group which may have a substituent.] Is preferable.
X ³ -Q ^{'-Y 3} - In the group represented by the formula, the alkylene group of ^{Y 3,} wherein ^Q' include the same ones having 1 to 4 carbon atoms of the alkylene groups listed.
Examples of the fluorinated alkylene group include groups in which part or all of the hydrogen atoms of the alkylene group have been substituted with fluorine atoms.
As Y ^3, _{specifically, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF (CF 2 CF 3) -, _{-C (CF 3) 2 -,} - CF 2 CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF ₃ ) —, —C (CF ₃ ) ₂ CF ₂ —, —CF (CF ₂ CF ₃ ) CF ₂ —, —CF (CF ₂ CF ₂ CF ₃ ) —, —C (CF ₃ ) (CF _{2 CF 3) -; - CHF} -, - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -, - CH (CF 3) CH 2 -, - CH (CF 2 _{CF 3) -, - C (} CH 3) (CF 3) -, - CH 2 CH 2 CH 2 CF 2 -, - C H ₂ CH ₂ CF ₂ CF ₂ —, —CH (CF ₃ ) CH ₂ CH ₂ —, —CH ₂ CH (CF ₃ ) CH ₂ —, —CH (CF ₃ ) CH (CF ₃ ) —, —C ( _{CF 3) 2 CH 2 -;} - CH 2 -, - CH 2 CH 2 -, - CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 -, - CH (CH 2 CH 3) -, - _{C (CH 3) 2 -,} - CH 2 CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 -, - CH (CH 3) CH _{(CH 3) -, - C} (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - CH (CH 2 CH 2 CH 3) -, - C (CH 3) (CH 2 CH ₃ ) — and the like.

Y ³ is preferably a fluorinated alkylene group, and particularly preferably a fluorinated alkylene group in which the carbon atom bonded to the adjacent sulfur atom is fluorinated. Examples of such fluorinated alkylene _{group, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF 2 CF 2 CF 2 CF 2 _{-, - CF (CF 3)} CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF 3) -, - C (CF 3) 2 CF 2 -, _{-CF (CF 2 CF 3) CF} 2 -; - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -; - CH 2 CH 2 CH 2 CF 2 -, - CH ₂ CH ₂ CF ₂ CF ₂ —, —CH ₂ CF ₂ CF ₂ CF ₂ — and the like can be mentioned.
Of _{these, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, or _CH 2 _CF 2 CF ₂ - is _{preferable, -CF 2 -, - CF 2} CF 2 - or -CF ₂ CF ₂ CF ₂ - is more preferable, -CF ₂ - is particularly preferred.

The alkylene group or fluorinated alkylene group may have a substituent. An alkylene group or a fluorinated alkylene group has a “substituent” means that part or all of the hydrogen atom or fluorine atom in the alkylene group or fluorinated alkylene group is substituted with an atom or group other than a hydrogen atom and a fluorine atom. Means that
Examples of the substituent that the alkylene group or fluorinated alkylene group may have include an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and a hydroxyl group.

-SO ₃ - ^"R 4 is a group represented by ^{X 3 -Q '-Y 3" -} R 4 As specific examples of, for example represented by any one of the following formulas (b1) ~ (b9) Anions.

［式中、ｑ１〜ｑ２はそれぞれ独立に１〜５の整数であり、ｑ３は１〜１２の整数であり、ｔ３は１〜３の整数であり、ｒ１〜ｒ２はそれぞれ独立に０〜３の整数であり、ｇは１〜２０の整数であり、Ｒ^７は置換基であり、ｎ１〜ｎ６はそれぞれ独立に０または１であり、ｖ０〜ｖ６はそれぞれ独立に０〜３の整数であり、ｗ１〜ｗ６はそれぞれ独立に０〜３の整数であり、Ｑ”は前記と同じである。］

[Wherein, q1 to q2 are each independently an integer of 1 to 5, q3 is an integer of 1 to 12, t3 is an integer of 1 to 3, and r1 to r2 are each independently 0 to 3] G is an integer of 1 to 20, R ⁷ is a substituent, n1 to n6 are each independently 0 or 1, v0 to v6 are each independently an integer of 0 to 3, w1 to w6 are each independently an integer of 0 to 3, and Q ″ is the same as above.]

Examples of the substituent for R ⁷ include those listed as the substituents that may substitute part of the hydrogen atoms bonded to the carbon atoms constituting the ring structure of the aliphatic cyclic group in the description of X ³ above, The thing similar to what was mentioned as a substituent which may substitute the hydrogen atom couple | bonded with the aromatic ring which an aromatic hydrocarbon group has is mentioned.
Code (r1 and r2, W1 to W6) attached to R ⁷ when is an integer of 2 or more, a plurality of the ^{R 7} groups may be the same, respectively, may be different.

Examples of V ⁻ in the formula (a0-1) include an anion represented by the following general formula (b-3) and an anion represented by the following general formula (b-4).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

In the formula (b-3), X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group preferably has 2 to 6 carbon atoms. More preferably 3 to 5 carbon atoms, most preferably 3 carbon atoms.
In formula (b-4), Y ″ and Z ″ each independently represent a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the carbon number of the alkyl group Is preferably 1 to 10, more preferably 1 to 7 carbon atoms, and most preferably 1 to 3 carbon atoms.
The number of carbon atoms of the X ″ alkylene group or the number of carbon atoms of the Y ″ and Z ″ alkyl groups is preferably as small as possible because the solubility in a resist solvent is good within the above-mentioned range of carbon numbers.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, the strength of the acid increases as the number of hydrogen atoms substituted with fluorine atoms increases, and high-energy light or electron beam of 200 nm or less This is preferable because the transparency to the surface is improved.
The fluorination rate of the alkylene group or alkyl group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkylene group or a perfluoroalkylene group in which all hydrogen atoms are substituted with fluorine atoms. A fluoroalkyl group;

V in the formula (a0-1) ^- as represented by the general formula ^"R 4" SO ₃ ^- "represented by anions (especially in, ^{R 4"} is ^{X 3} -Q ^'-Y 3 - is a group represented by The anions represented by the above formulas (b1) to (b9) are preferred.

Specific examples of the group represented by formula (a0-1) are shown below. In the formula, V ⁻ is the same as described above.

  As the structural unit having the group represented by the formula (a0-1) (hereinafter referred to as “structural unit (a0-1)”), a structural unit represented by the following formula (a0-11) is preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基であり、Ｑ^１、Ｒ^３〜Ｒ^５、Ｖ⁻は前記同様である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Q ¹ , R ^{3 to} R ⁵ , and V ⁻ are the same as described above. ]

In formula (a0-11), the alkyl group of R is preferably a linear or branched alkyl group, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group. Group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like.
Examples of the halogenated alkyl group for R include groups in which some or all of the hydrogen atoms of the aforementioned R alkyl group have been substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.
In formula (a0-11), Q ¹ , R ^{3 to} R ⁵ , and V ⁻ are the same as described above.

(Structural unit having a group represented by the formula (a0-2))
In formula (a0-2), Q ² represents a single bond or a divalent linking group. Examples of the divalent linking group for Q ² include the same divalent linking groups as those described above for L ⁰¹ in formula (I-1). Among these, Q ² in the present invention is preferably a single bond, a linear / branched alkylene group, an ester bond [—C (═O) —O—], or a combination thereof.

In formula (a0-2), A ⁻ represents an organic group containing an anion.
A ⁻ is not particularly limited as long as it includes a site which is generated by exposure and becomes an acid anion. However, sulfonate anion, carbanion, carboxylate anion, sulfonylimide anion, bis (alkylsulfonyl) A group capable of generating an imide anion or a tris (alkylsulfonyl) methide anion is preferred.
Among them, A ^- as is preferably a group represented by the following formula (a0-2-an1) ~ (a0-2 -an4).

［Ｗ^０は置換基を有していてもよい炭素数１〜３０の炭化水素基である。Ｚ^３は−Ｃ（＝Ｏ）−Ｏ−、−ＳＯ_２−又は置換基を有していてもよい炭化水素基であり、Ｚ^４及びＺ^５はそれぞれ独立に−Ｃ（＝Ｏ）−又は−ＳＯ_２−である。Ｒ^６２及びＲ^６３はそれぞれ独立にフッ素原子を有していてもよい炭化水素基である。Ｚ^１は−Ｃ（＝Ｏ）−、−ＳＯ_２−、−Ｃ（＝Ｏ）−Ｏ−又は単結合であり、Ｚ^２は−Ｃ（＝Ｏ）−又は−ＳＯ_２−である。Ｒ^６１はフッ素原子を有していてもよい炭化水素基である。Ｒ^６４はフッ素原子を有していてもよい炭化水素基である。］

[W ⁰ is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent. Z ³ is —C (═O) —O—, —SO ₂ — or an optionally substituted hydrocarbon group, and Z ⁴ and Z ⁵ are each independently —C (═O) — or -SO ₂ - is. R ⁶² and R ⁶³ are each independently a hydrocarbon group optionally having a fluorine atom. Z ¹ is —C (═O) —, —SO ₂ —, —C (═O) —O— or a single bond, and Z ² is —C (═O) — or —SO ₂ —. R ⁶¹ is a hydrocarbon group which may have a fluorine atom. R ⁶⁴ is a hydrocarbon group which may have a fluorine atom. ]

In Formula (a0-2-an1), W ⁰ is a hydrocarbon group having 1 to 30 carbon atoms that may have a substituent.
The hydrocarbon group having 1 to 30 carbon atoms which may have a substituent of W ⁰ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may have the above formula (I-1) The same thing as the aliphatic hydrocarbon group demonstrated by the divalent coupling group in ^L01 in the inside and an aromatic hydrocarbon group is mentioned.
Of these, a group represented by the following formula (a0-2-an1-1) is preferable.

［式中、Ｒ^ｆ１及びＲ^ｆ２はそれぞれ独立に水素原子、アルキル基、フッ素原子、又はフッ素化アルキル基であり、Ｒ^ｆ１、Ｒ^ｆ２のうち少なくとも１つはフッ素原子又はフッ素化アルキル基であり、ｐ０は１〜８の整数である。］

[Wherein, R ^f1 and R ^f2 each independently represent a hydrogen atom, an alkyl group, a fluorine atom, or a fluorinated alkyl group, and at least one of R ^f1 and R ^f2 is a fluorine atom or a fluorinated alkyl group. , P0 is an integer of 1-8. ]

R ^f1 and R ^f2 are each independently a hydrogen atom, an alkyl group, a fluorine atom, or a fluorinated alkyl group, and at least one of R ^f1 and R ^f2 is a fluorine atom or a fluorinated alkyl group.
As the alkyl group for R ^f1 and R ^f2 , an alkyl group having 1 to 5 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group. Group, pentyl group, isopentyl group, neopentyl group and the like.
Examples of the fluorinated alkyl group of ^{R f1,} R ^f2, group in which part or all of the hydrogen atoms of the alkyl group of the ^{R f1, R f2} is substituted with a fluorine atom is preferred.
R ^f1 and R ^f2 are preferably a fluorine atom or a fluorinated alkyl group.
In formula (a0-2-an1-1), p0 is an integer of 1 to 8, preferably an integer of 1 to 4, and more preferably 1 or 2.
Moreover, as a hydrocarbon group which may have a substituent of W ⁰ , as a preferable example other than the above formula (a0-2-an1-1), an aliphatic ring which may have a substituent And a group obtained by removing two or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, camphor, benzene or the like (having a substituent). More preferably).

In formula (a0-2-an2), Z ³ represents —C (═O) —O—, —SO ₂ — or a hydrocarbon group which may have a substituent. As the hydrocarbon group which may have a substituent of Z ³ , “which may have a substituent” mentioned in the description of the divalent linking group in L ⁰¹ in the above formula (I-1) is used. The thing similar to "a bivalent hydrocarbon group" is mentioned. Among these, Z ³ is preferably —SO ₂ —.
In formula (a0-2-an2), Z ⁴ and Z ⁵ are each independently —C (═O) — or —SO ₂ —, preferably at least one of —SO ₂ —, Is more preferably —SO ₂ —.
R ⁶² and R ⁶³ are each independently a hydrocarbon group which may have a fluorine atom, and examples thereof include those similar to the hydrocarbon group which may have a fluorine atom in R ⁶¹ described later. .

In formula (a0-2-an3), Z ¹ represents —C (═O) —, —SO ₂ —, —C (═O) —O—, or a single bond. When Z ¹ is a single bond, N ^{− in} the formula is preferably not directly bonded to —C (═O) — on the side opposite to the side bonded to Z ² (that is, the left end in the formula).

In Formula (a0-2-an3), Z ² is —C (═O) — or —SO ₂ —, and preferably —SO ₂ —.
R ⁶¹ is a hydrocarbon group which may have a fluorine atom. Examples of the hydrocarbon group for R ⁶¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.
The alkyl group for R ⁶¹ is preferably one having 1 to 8 carbon atoms, more preferably one having 1 to 6 carbon atoms, still more preferably one having 1 to 4 carbon atoms, and even if linear, it is branched. It may be a chain. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group and the like are preferable.
The monovalent alicyclic hydrocarbon group in R ⁶¹ is preferably those having 3 to 20 carbon atoms, more preferably those having 3 to 12 carbon atoms, and may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms. Adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.
The aryl group in R ⁶¹ is preferably those having 6 to 18 carbon atoms, more preferably those having 6 to 10 carbon atoms, and particularly preferably a phenyl group.
Aralkyl group in R ⁶¹ include those in which the "aryl group for R ^61" alkylene group and the above C1-8 bonded are preferred examples. More preferred is an aralkyl group in which an alkylene group having 1 to 6 carbon atoms and the above “aryl group in R ⁶¹ ” are bonded, and an aralkyl group in which an alkylene group having 1 to 4 carbon atoms and the above “aryl group in R ⁶¹ ” are bonded. Is particularly preferred.
In the hydrocarbon group for R ⁶¹ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms. More preferably. Especially, it is especially preferable that it is the perfluoroalkyl group by which all the hydrogen atoms of the alkyl group mentioned above were substituted by the fluorine atom.

In the formula (a0-2-an4), R ⁶⁴ represents a hydrocarbon group that may have a fluorine atom. As the hydrocarbon group for R ⁶⁴ , an alkylene group, a divalent alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from an aryl group, a group in which one or more hydrogen atoms have been removed from an aralkyl group, etc. Is mentioned.
Specific examples of the hydrocarbon group for R ⁶⁴ include those exemplified in the description of the hydrocarbon group for R ⁶¹ (an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, an aralkyl group, and the like). And a group in which one or more hydrogen atoms are removed.
In the hydrocarbon group for R ⁶⁴ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms. More preferably.

Among the above, for example, when A ⁻ is a group having a fluorine atom among the groups represented by the formula (a0-2-an1) (particularly, the group represented by the formula (a0-2-an1-1)). Or a group represented by (a0-2-an2) or a group represented by formula (a0-2-an3) in which Z ¹ and Z ² are —SO ₂ —, the structural unit ( From a0), relatively strong acids such as fluorinated alkyl sulfonate anions, carbanions, sulfonylimide anions can be generated.
On the other hand, when A ⁻ has no fluorine atom among the groups represented by the formula (a0-2-an1), the group represented by the formula (a0-2-an4), and Z ¹ and Z ² are When having a group represented by the formula (a0-2-an3) which is —C (═O) —, the structural unit (a0) is exposed to an alkylsulfonate anion, an arylsulfonate anion, a carboxylate anion, an imide anion by exposure. A relatively weak acid such as can be generated.

Since the acid having the desired acid strength can be generated from the structural unit (a0) as described above, the function of the acid generated from the structural unit (a0) in the resist composition can be appropriately determined, according to the function a ^- it can also be selected.
For example, when the structural unit (a0) plays a role similar to that of the acid generator usually used in a resist composition, it is preferable to select A ⁻ that generates a strong acid.
For example, when the structural unit (a0) has the same function as a quencher (quencher that traps a strong acid by salt exchange with a strong acid generated from an acid generator) usually used in a resist composition, a weak acid is used. It is preferable to select A ⁻ to be generated.
Here, the strong acid and the weak acid are the relationship with the activation energy of an acid-decomposable group that is decomposed by the action of an acid as contained in the structural unit (a1) described later, and the acid generator acid used together. It is determined in relation to strength. Therefore, the above-mentioned “relatively weak acid” cannot always be used as a quencher.

In formula (a0-2), M ^{m +} is a counter cation, and m is an integer of 1 to 3. However, the organic cation has only one aromatic ring or no aromatic ring.
As the counter cation of M ^{m +} , an organic cation is preferable. The organic cation is not particularly limited. For example, among organic cations conventionally known as a cation moiety such as a photodegradable base used in a resist composition quencher or an onium-based acid generator of a resist composition. One having only one aromatic ring or not having an aromatic ring can be used. As such an organic cation, for example, a cation represented by the following general formula (m-1) or (m-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”は、それぞれ独立に、置換基を有していてもよいアリール基、アルキル基またはアルケニル基を表す。但し、Ｒ^１”〜Ｒ^３”はこれらの全体で芳香環を１個のみ有するか、又は芳香環を有さない。Ｒ^１”〜Ｒ^３”のうち、いずれか２つが相互に結合して式中のイオウ原子と共に完を形成していてもよい。Ｒ^５”〜Ｒ^６”は、それそれ独立に、置換基を有していてもよいアリール基、アルキル基又はアルケニル基を表す、但し、Ｒ^５”〜Ｒ^６”はこれらの全体で芳香環を１個のみ有するか、又は芳香環を有さない。］

[Wherein, R ¹ ″ to R ³ ″ each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent. However, R ¹ ″ to R ³ ″ have only one aromatic ring as a whole or no aromatic ring . Any two of R ¹ ″ to R ³ ″ may be bonded to each other to form complete together with the sulfur atom in the formula. R ⁵ ″ to R ⁶ ″ each independently represents an aryl group, alkyl group or alkenyl group which may have a substituent, provided that R ⁵ ″ to R ⁶ ″ are aromatic rings in their entirety. Or has no aromatic ring . ]

In the formula (m-1), an aryl group which may have a substituent in R ¹ ″ to R ³ ″, an alkyl group which may have a substituent, or a substituent. Examples of the alkenyl group include those similar to the aryl group, alkyl group, and alkenyl group mentioned in the description of R ^{4 to} R ^{5 in} the general formula (a0-1).
As the ring formed when any two of R ¹ ″ to R ³ ″ in the formula (m-1) are bonded to each other to form a ring together with the sulfur atom in the formula, the general formula (a0 The thing similar to what was mentioned as a ring which R < ⁴ > -R < ⁵ > in -1) couple | bonds together and forms with the sulfur atom in a formula is mentioned.
In formula (m-2), examples of the aryl group, alkyl group, and alkenyl group of R ⁵ ″ to R ⁶ ″ include the same aryl groups as R ¹ ″ to R ³ ″.
In the formula (m-1), R ¹ ″ to R ³ ″ have only one aromatic ring as a whole, or no aromatic ring. In the formula (m-2), R ⁵ ″ to R ³ ″ R ⁶ ″ in total has only one aromatic ring or no aromatic ring. Since R ¹ ″ to R ³ ″ have no aromatic ring or one aromatic ring, the acid generating group has low sensitivity to DUV which is OoB light and high sensitivity to EUV. can do.

  Especially, as a cation of a formula (a0-2), the cation represented by the said formula (m-1) is preferable. Specifically, among the cation moieties of the compound represented by the formula (m-1), specifically, cation moieties represented by the following formulas (m1-1-1) to (m1-1-2) Is mentioned.

In the cation moiety of the compound represented by the formula (m-1), any two of R ¹ ″ to R ³ ″ are bonded to each other to form a ring together with the sulfur atom in the formula. Preferable specific examples of the case include, for example, a cation moiety represented by the following formula (m1-3).

［式中、Ｒ^９は、置換基を有していてもよいフェニル基、ナフチル基または炭素数１〜５のアルキル基、アルコキシ基、水酸基であり、Ｑ^９は単結合、−Ｃ（＝Ｏ）−Ｏ−又は−Ｃ（＝Ｏ）−であり、Ｒ^４’は単結合又は炭素数１〜５のアルキレン基であり、ｕは１〜３の整数である。］

[In the formula, R ⁹ is a phenyl group, a naphthyl group, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a hydroxyl group, which may have a substituent, and Q ⁹ is a single bond, —C (═O ) —O— or —C (═O) —, R ⁴ ′ is a single bond or an alkylene group having 1 to 5 carbon atoms, and u is an integer of 1 to 3. ]

In formula (m1-3), R ⁹ represents a phenyl group, a naphthyl group, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a hydroxyl group, which may have a substituent. Examples of the substituent include a substituent in the substituted aryl group exemplified in the description of the aryl group of R ¹ ″ to R ³ ″ (an alkyl group, an alkoxy group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, a halogen atom). Atom, hydroxyl group, oxo group (═O), aryl group, —C (═O) —O—R ⁶ ″, —O—C (═O) —R ⁷ ″, —O—R ⁸ ″, the above general formula ^{: -O-R 50 -C (=} O) based on ^{R 56} is replaced by ^{R 56} 'in the ^{-O-R 56,} etc.) to be similar.
R ⁴ ′ is an alkylene group having 1 to 5 carbon atoms.
u is an integer of 1 to 3, and 1 or 2 is most preferable.
Preferable examples of the cation represented by the formula (m1-3) include those shown below.

In formula (m1-3-1), R ^C represents a substituent. Examples of the substituent include the substituents exemplified in the description of the substituted aryl group (alkyl group, alkoxy group, alkoxyalkyloxy group, alkoxycarbonylalkyloxy group, halogen atom, hydroxyl group, oxo group (═O), Aryl groups, —C (═O) —O—R ⁶ ″, —O—C (═O) —R ⁷ ″, —O—R ⁸ ″).

As the structural unit having a group represented by the formula (a0-2) (hereinafter referred to as “structural unit (a0-2)”), the following formulas (a0-2-11) to (a0-2-14) may be used. , (A0-2-21) to (a0-2-25), (a0-2-31) to (a0-2-32), (a0-2-41) to (a0-2-44) At least one selected from the group consisting of structural units is preferred.
Among these, structural units represented by the following formulas (a0-2-11) to (a0-2-14) are respectively represented by the following formulas (a0-2-11-1) to (a0-2-13-). The structural unit represented by 1) is preferred.

［式中、Ｒ、Ｑ^２１〜Ｑ^２３、Ｗ^０、Ｒ^ｑ１、（Ｍ^ｍ＋）_１／ｍは前記と同様である。Ｒ^ａｒは置換基を有していてもよい２価の芳香族基であって、（Ｃ）成分の説明中において上述したＲ^ａｒと同様である。Ｒ^ｎは水素原子又は炭素数１〜５のアルキル基である。］

[Wherein, R, Q ^{21 to} Q ²³ , W ⁰ , R ^q1 , (M ^{m +} ) _{1 / m} are the same as described above. R ^ar is a divalent aromatic group which may have a substituent, and is the same as R ^ar described above in the description of the component (C). R ⁿ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ]

［式中、Ｒ、Ｒ^ｆ１、Ｒ^ｆ２、ｐ０、、Ｒ^ｎ、（Ｍ^ｍ＋）_１／ｍは前記同様であり、Ｑ^２１はそれぞれ独立に単結合又は２価の連結基である。Ｑ^２２は２価の連結基である。Ｑ^２３は−Ｏ−、−ＣＨ_２−Ｏ−、又は−Ｃ（＝Ｏ）−Ｏ−を含有する基である。Ｒ^ｑ１はフッ素原子又はフッ素化アルキル基である。］

[Wherein, R, R ^f1 , R ^f2 , p0, R ⁿ , (M ^{m +} ) _{1 / m} are the same as described above, and Q ²¹ each independently represents a single bond or a divalent linking group. Q ²² is a divalent linking group. Q ²³ is a group containing —O—, —CH ₂ —O—, or —C (═O) —O—. R ^q1 is a fluorine atom or a fluorinated alkyl group. ]

［式中、Ｒ、Ｑ^２１〜Ｑ^２３、Ｚ^３〜Ｚ^５、Ｒ^６２〜Ｒ^６３、Ｒ^ｎ、Ｒ^ｑ１、（Ｍ^ｍ＋）_１／ｍは前記同様である。ｎ６０は０〜３の整数である。］

[Wherein, R, Q ^{21 to} Q ²³ , Z ^{3 to} Z ⁵ , R ^{62 to} R ⁶³ , R ⁿ , R ^q1 , (M ^{m +} ) _{1 / m} are the same as described above. n60 is an integer of 0-3. ]

［式中、Ｒ、Ｚ^１〜Ｚ^２、Ｒ^ｎ、（Ｍ^ｍ＋）_１／ｍは前記と同様であり、Ｑ^２４、Ｑ^２５はそれぞれ独立に単結合又は２価の連結基である。］

[Wherein, R, Z ^{1 to} Z ² , R ⁿ , (M ^{m +} ) _{1 / m} are the same as described above, and Q ²⁴ and Q ²⁵ are each independently a single bond or a divalent linking group. ]

［式中、Ｒ、Ｒ^ｎ、（Ｍ^ｍ＋）_１／ｍは前記と同様であり、Ｑ^２６〜Ｑ^２８はそれぞれ独立に単結合又は２価の連結基である。ｎ３０は０〜３の整数である。］

[Wherein, R, R ⁿ and (M ^{m +} ) _{1 / m} are the same as defined above, and Q ^{26 to} Q ²⁸ each independently represent a single bond or a divalent linking group. n30 is an integer of 0-3. ]

In formulas (a0-2-11) to (a0-2-14), R, W ⁰ , R ^q1 , R ^ar (M ^{m +} ) _{1 / m} are the same as described above.
Q ²¹ is a single bond or a divalent linking group. Examples of the divalent linking group for Q ²¹ include the same divalent linking groups as for L ⁰¹ in formula (I-1). Among these, Q ²¹ is preferably a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a divalent linking group containing a hetero atom; A branched alkylene group, a combination of a linear or branched alkylene group and a divalent linking group containing a heteroatom, a cyclic aliphatic hydrocarbon group and a divalent linking group containing a heteroatom. A combination or a combination of an aromatic hydrocarbon group and a divalent linking group containing a hetero atom is more preferable; a linear or branched alkylene group, a linear or branched alkylene group and an ester bond [- A combination of C (═O) —O—] with a divalent alicyclic hydrocarbon group and an ester bond [—C (═O) —O—] is particularly preferred; linear or branched An alkylene group of A combination of a branched alkylene group and an ester bond [—C (═O) —O—] is most preferred.

In formula (a0-2-12), Q ²² represents a divalent linking group, and examples thereof include the same divalent linking groups as those described above for L ⁰¹ in formula (I-1). It is preferably a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, or a divalent aromatic hydrocarbon group mentioned in the above, particularly preferably a linear alkylene group, a methylene group or Most preferred is an ethylene group.
In formula (a0-2-12), R ⁿ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. As a C1-C5 alkyl group, the same thing as the C1-C5 alkyl group of said R is mentioned. Of these, R ⁿ is preferably a hydrogen atom or a methyl group.

In formula (a0-2-13), Q ²³ represents a group containing —O—, —CH ₂ —O—, or —C (═O) —O—.
Q ²³ is specifically a group consisting of —O—, —CH ₂ —O—, or —C (═O) —O—; —O—, —CH ₂ —O— or —C (═O). And a group composed of —O— and a divalent hydrocarbon group which may have a substituent.
As the divalent hydrocarbon group which may have such a substituent, the divalent which may have the substituent mentioned for the divalent linking group in L ⁰¹ in the above formula (I-1). And the same hydrocarbon groups as those described above. Among them, the “divalent hydrocarbon group” in Q ¹ is preferably an aliphatic hydrocarbon group, and more preferably a linear or branched alkylene group.
Q ²³ is preferably a group consisting of —C (═O) —O— and a divalent hydrocarbon group which may have a substituent, and —C (═O) —O— and aliphatic carbonization. A group consisting of a hydrogen group is more preferred, and a group consisting of —C (═O) —O— and a linear or branched alkylene group is more preferred.
Specific examples suitable for Q ^23, in particular, a group represented by the following general formula ^(Q 23 -1).

［式（Ｑ^２３−１）中、Ｒ^ｑ２及びＲ^ｑ３はそれぞれ独立に水素原子、アルキル基又はフッ素化アルキル基であり、互いに結合して環を形成していてもよい。］

[In Formula (Q ²³ -1), R ^q2 and R ^q3 each independently represent a hydrogen atom, an alkyl group, or a fluorinated alkyl group, and may be bonded to each other to form a ring. ]

In the formula (Q ²³ -1), the alkyl group in R ^q2 and R ^q3 may be linear, branched or cyclic, and is preferably linear or branched.
In the case of a linear or branched alkyl group, the number of carbon atoms is preferably 1 to 5, more preferably an ethyl group or a methyl group, and particularly preferably an ethyl group.
In the case of a cyclic alkyl group, the number of carbon atoms is preferably 4 to 15, more preferably 4 to 12, and most preferably 5 to 10. Specific examples include monocycloalkanes; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. It is done. Of these, a group in which one or more hydrogen atoms have been removed from adamantane is preferable.

The fluorinated alkyl group for R ^q2 and R ^q3 is a group in which part or all of the hydrogen atoms in the alkyl group are substituted with fluorine atoms.
In the fluorinated alkyl group, the alkyl group not substituted with a fluorine atom may be linear, branched or cyclic, and the same as the above-mentioned “alkyl group in R ^q2 and R ^q3 ”. Can be mentioned.

R ^q2 and R ^q3 may be bonded to each other to form a ring, and the ring formed by R ^q2 and R ^q3 and the carbon atom to which they are bonded includes a monocyclo group in the cyclic alkyl group. The thing remove | excluding two hydrogen atoms from alkane or polycycloalkane can be illustrated, It is preferable that it is a 4-10 membered ring, and it is more preferable that it is a 5-7 membered ring.

Among the above, R ^q2 and R ^q3 are preferably a hydrogen atom or an alkyl group.

In formula (a0-2-13), R ^q1 represents a fluorine atom or a fluorinated alkyl group.
In the fluorinated alkyl group for R ^q1 , the alkyl group not substituted with a fluorine atom may be linear, branched or cyclic.
In the case of a linear or branched alkyl group, the number of carbon atoms is preferably 1 to 5, more preferably 1 to 3, and particularly preferably 1 to 2. .
In the case of a cyclic alkyl group, the number of carbon atoms is preferably 4 to 15, more preferably 4 to 12, and still more preferably 5 to 10. Specific examples include monocycloalkanes; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, examples include monocycloalkanes such as cyclopentane and cyclohexane; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. .
In the fluorinated alkyl group, the ratio of the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms contained in the fluorinated alkyl group (fluorination rate (%)) is preferably 30 to 100%. 50 to 100% is more preferable. The higher the fluorination rate, the higher the hydrophobicity of the resist film.
Among the above, R ^q1 is preferably a fluorine atom.
In formulas (a0-2-11-1) to (a0-2-13-1), R, Q ^{21 to} Q ²³ , R ^f1 , R ^f2 , p0, R ⁿ , (M ^{m +} ) _{1 / m} is the above It is the same.

In the formulas (a0-2-21) to (a0-2-25), R, Q ^{21 to} Q ²³ , Z ^{3 to} Z ⁵ , R ^{62 to} R ⁶³ , R ⁿ , R ^q1 , (M ^{m +} ) _{1 / m} is the same as described above.
In formula (a0-2-24), n60 is an integer of 0 to 3, and is preferably 0 or 1.

In formulas (a0-2-31) to (a0-2-32), R, Z ^{1 to} Z ² , R ⁿ , (M ^{m +} ) _{1 / m} are the same as described above, and Q ²⁴ and Q ²⁵ are respectively It is independently a single bond or a divalent linking group.
Examples of the divalent linking group for Q ²⁴ and Q ²⁵ include the same divalent linking groups as those described above for L ⁰¹ in formula (I-1). As described above, if ^{Z 1} is a single ^bond, end which binds to ^{Z 1} of Q ^{24, Q 25} is -C (= O) - is not preferred. The divalent linking group for Q ²⁴ and Q ²⁵ is particularly preferably a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, or a divalent linking group containing a hetero atom. Among these, a linear or branched alkylene group and a cyclic aliphatic hydrocarbon group are preferable, and a linear alkylene group and a cyclic aliphatic hydrocarbon group are more preferable.

In formulas (a0-2-41) to (a0-2-44), R, R ⁿ , (M ^{m +} ) _{1 / m} are the same as described above, and Q ^{26 to} Q ²⁸ are each independently a single bond or 2 Valent linking group. Q ²⁶ to Q ²⁸ are the same as the ^{Q 24, Q 25.}
In formula (a0-2-44), n30 is an integer of 0 to 3, and is preferably 0 or 1.

Specific examples of the structural unit (a0-2) are shown below. In the following formulas, R ^α is a hydrogen atom, a methyl group or a trifluoromethyl group, and (M ^{m +} ) _{1 / m} is the same as described above.

The component (A1) may have only one type of structural unit (a0), or may have two or more types in combination.
In the component (A1), the proportion of the structural unit (a0) is preferably 1 to 50 mol%, more preferably 1 to 45 mol%, more preferably 3 to 40 with respect to all the structural units constituting the polymer. More preferred is mol%, and particularly preferred is 5 to 35 mol%. By setting it to 1 mol% or more, the effect of improving lithography properties such as sensitivity and resolution can be sufficiently obtained, and by setting it to the upper limit or less, it becomes easy to balance with other structural units. Moreover, sufficient solubility with respect to the resist solvent (component (S) described later) can be secured.

The component (A1) may have a structural unit other than the structural unit (a0). As such a structural unit, a number of hitherto known compounds can be used as resist resins for ArF excimer laser, KrF excimer laser (preferably for ArF excimer laser), and the like. For example,
Structural unit (a0) that generates acid upon exposure;
A structural unit (a1) containing an acid-decomposable group whose polarity is increased by the action of an acid;
A structural unit (a2) containing a —SO ₂ — containing cyclic group or a lactone-containing cyclic group;
A structural unit (a3) containing a polar group;
A structural unit (a4) containing a non-acid-dissociable cyclic group;
Etc.

When component (A) is component (A-1) (a base material component that generates an acid upon exposure and increases its polarity by the action of acid), component (A1) increases its polarity by the action of acid. It preferably contains an acid-decomposable group.
As described in the structural unit (c1), the “acid-decomposable group” is an acid (an acid generated from the structural unit (a0) by exposure or an acid generator component (B) which is an optional component). ) Is an acid-decomposable group capable of cleaving at least some of the bonds in the structure of the acid-decomposable group.
When the structural unit (a0) contains an acid-decomposable group, the component (A1) may be composed only of the structural unit (a0), and the acid-decomposable group whose polarity is increased by the action of an acid. The structural unit (a1) may be included.
When the structural unit (a0) does not include an acid-decomposable group, the component (A1) needs to have a structural unit (a1) in addition to the structural unit (a0).
In the present invention, the component (A) is preferably the component (A-1). That is, the component (A1) is a resin component that generates an acid upon exposure and increases its polarity by the action of the acid, and the resist composition of the present invention becomes a positive type in an alkali development process and is negative in a solvent development process. It is preferably a chemically amplified resist composition that becomes a mold.

(Structural unit (a1))
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid.
Examples of the acid-decomposable group include the same groups as those described in the description of the structural unit (c2).
The structural unit (a1) is not particularly limited as long as it has an acid-decomposable group, but an acrylic group in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. A structural unit derived from an acid ester and comprising a structural unit (a11) containing an acid-decomposable group, a hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and hydrogen bonded to a benzene ring A structural unit in which a hydrogen atom of a hydroxyl group of a structural unit derived from hydroxystyrene which may be substituted with a substituent other than a hydroxyl group is substituted with an acid-dissociable group or a substituent containing an acid-dissociable group ( a12), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring may be substituted with a substituent other than a hydroxyl group (hydroxynaphtho Structural units hydroxyl hydrogen atoms of constituent units derived from alkylene) is replaced by a substituent containing an acid-dissociable group or an acid-dissociable group (a13), and the like. The structural unit (a11) is preferable in terms of line edge roughness, and the structural units (a12) to (a13) are preferable in that the EUV wavelength can be easily absorbed and the influence of the OoB light on the acid generating component can be further reduced.

{Structural unit (a11)}
The structural unit (a11) is a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent and includes an acid-decomposable group.
Examples of the structural unit (a11) include a structural unit represented by the following general formula (a1-0-1), a structural unit represented by the following general formula (a1-0-2), and the like.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり；Ｘ^１は酸解離性基であり；Ｙ^２は２価の連結基であり；Ｘ^２は酸解離性基である。］

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; X ¹ is an acid dissociable group; Y ² is a divalent linking group. Yes; X ² is an acid-dissociable group. ]

In general formula (a1-0-1), the alkyl group and halogenated alkyl group represented by R are the alkyl group and halogenated alkyl group mentioned as the substituent at the α-position in the description of the α-substituted acrylate ester, respectively. The same thing is mentioned. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, and most preferably a hydrogen atom or a methyl group.
X ¹ is not particularly limited as long as it is an acid dissociable group, and examples thereof include the above-described tertiary alkyl ester type acid dissociable groups, acetal type acid dissociable groups, and the like. An ester type acid dissociable group is preferred.
In general formula (a1-0-2), R is the same as defined above.
X ² is the same as X ¹ in formula (a1-0-1).
Examples of the divalent linking group of Y ^2, but are not limited to, divalent hydrocarbon group which may have a substituent group, and a divalent linking group containing a hetero atom as preferred. As the divalent hydrocarbon group which may have these substituents and the divalent linking group containing a hetero atom, respectively, in the general formula (I-1) mentioned in the description of the component (C), Examples thereof include the same divalent linking groups as L ⁰¹ .
Y ² is particularly preferably a linear or branched alkylene group, a divalent alicyclic hydrocarbon group, or a divalent linking group containing a hetero atom.
When Y ² is a linear or branched alkylene group, the alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and 1 to 4 carbon atoms. It is particularly preferred that it has 1 to 3 carbon atoms. Specifically, in the description of the divalent linking group in R ^1, the same as the linear alkylene group and the branched alkylene group mentioned as the linear or branched aliphatic hydrocarbon group. Things.
When Y ² is a divalent alicyclic hydrocarbon group, as the alicyclic hydrocarbon group, in the description of the divalent linking group in R ^0-1 , “aliphatic containing a ring in the structure”. The thing similar to the alicyclic hydrocarbon group quoted as "hydrocarbon group" is mentioned.
The alicyclic hydrocarbon group is particularly preferably a group in which two or more hydrogen atoms have been removed from cyclopentane, cyclohexane, norbornane, isobornane, adamantane, tricyclodecane or tetracyclododecane.

When Y ² is a divalent linking group containing a hetero atom, preferred examples of the linking group include —O—, —C (═O) —O—, —C (═O) —, —O—C. (═O) —O—, —C (═O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group or an acyl group), —S—, —S ( _{= O) 2 -, - S} (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - [Y 21 -C (= O) -O] m '-Y 22 - or - A group represented by Y ²¹ —O—C (═O) —Y ²² —, wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent. , O is an oxygen atom, and m ′ is an integer of 0-3. ] Etc. are mentioned.
When Y ² is —NH—, H may be substituted with a substituent such as an alkyl group or an aryl group (aromatic group). The substituent (alkyl group, aryl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - [Y 21 -C (= O) -O] m '-Y 22 - or ^{-Y 21 -O-C (= O} ) -Y 22 - ^{In, Y 21} And Y ²² are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same groups as those described above as the “divalent hydrocarbon group which may have a substituent” for Y ² .
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, m ′ is an integer of 0 to 3, preferably an integer of 0 to 2, Or 1 is more preferable, and 1 is particularly preferable. That is, the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — is represented by the formula —Y ²¹ —C (═O) —O—Y ²² —. The group is particularly preferred. Among these, a group represented by the formula — (CH ₂ ) _{a ′} —C (═O) —O— (CH ₂ ) _{b ′} — is preferable. In the formula, a ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.
The divalent linking group containing a hetero atom in Y ² is preferably an organic group comprising a combination of at least one kind, a non-hydrocarbon group and a divalent hydrocarbon group. Among these, a linear group having an oxygen atom as a hetero atom, for example, a group containing an ether bond or an ester bond, is preferable, and the above formulas -Y ²¹ -O-Y ²² -,-[Y ²¹ -C (= O ) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (═O) —Y ²² — is more preferred, and the group represented by the formula — [Y ²¹ —C (═O) —O] _The group represented by m′—Y ²² — or —Y ²¹ —O—C (═O) —Y ²² — is preferred.

Among these, Y ² is preferably a linear or branched alkylene group or a divalent linking group containing a hetero atom, and is a linear or branched alkylene group, the formula -Y ²¹ A group represented by —O—Y ²² —, a group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, or a group represented by the formula —Y ²¹ —O—C ( The group represented by ═O) —Y ²² — is more preferable.

  More specifically, examples of the structural unit (a11) include structural units represented by general formulas (a1-1) to (a1-4) shown below.

［式中、Ｒ、Ｒ^１’、Ｒ^２’、ｎ、ＹおよびＹ^２はそれぞれ前記と同じであり、Ｘ’は第３級アルキルエステル型酸解離性基を表す。］’

[Wherein, R, R ¹ ′, R ² ′, n, Y and Y ² are the same as defined above, and X ′ represents a tertiary alkyl ester-type acid dissociable group. ] '

In the formula, X ′ is the same as the tertiary alkyl ester-type acid dissociable group.
^{R 1 ', R 2',} n, as the Y, respectively, ^{R 1} in the general formula listed in the description of "acetal-type acid dissociable group" described above ^{(p1) ', R 2'} , n, similarly to the Y Can be mentioned.
The Y ^2, the same groups as those described above for ^{Y 2} in the general formula (a1-0-2).
Specific examples of the structural units represented by the general formulas (a1-1) to (a1-4) are shown below.
In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

  In the present invention, as the structural unit (a11), a structural unit represented by the following general formula (a1-0-11), a structural unit represented by the following general formula (a1-0-12), and the following general formula ( It preferably has at least one selected from the group consisting of a structural unit represented by a1-0-13) and a structural unit represented by the following general formula (a1-0-2). Among these, a structural unit represented by the formula (a1-0-11), a structural unit represented by the following general formula (a1-0-12), and a structure represented by the following general formula (a1-0-2) It is preferable to have at least one selected from the group consisting of units.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｒ^２１はアルキル基であり、Ｒ^２２は、当該Ｒ^２２が結合した炭素原子と共に脂肪族単環式基を形成する基であり、Ｒ^２３は分岐状のアルキル基であり、Ｒ^２４は、当該Ｒ^２４が結合した炭素原子と共に脂肪族多環式基を形成する基であり、Ｒ^２５は炭素数１〜５の直鎖状のアルキル基である。Ｙ^２は２価の連結基であり、Ｘ^２は酸解離性基である。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, R ²¹ is an alkyl group, and R ²² is a carbon to which R ²² is bonded. A group that forms an aliphatic monocyclic group together with an atom, R ²³ is a branched alkyl group, and R ²⁴ is a group that forms an aliphatic polycyclic group together with the carbon atom to which R ²⁴ is bonded. R ²⁵ is a linear alkyl group having 1 to 5 carbon atoms. Y ² is a divalent linking group, and X ² is an acid dissociable group. ]

In each formula, the description of R, Y ² and X ² is the same as described above.
In formula (a1-0-11), examples of the alkyl group for R ²¹ include the same alkyl groups as those described above for R ¹⁴ in formulas (1-1) to (1-9). Group or isopropyl group is preferred.
R ²² is, the aliphatic monocyclic group formed together with the carbon atom to which R ²² is bonded, the same aliphatic cyclic groups as those in the aforementioned tertiary alkyl ester-type acid dissociable groups, a monocyclic group The thing similar to what is is mentioned. Specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane is preferably a 3- to 11-membered ring, more preferably a 3- to 8-membered ring, further preferably a 4- to 6-membered ring, and particularly preferably a 5- or 6-membered ring.
In the monocycloalkane, a part of carbon atoms constituting the ring may or may not be substituted with an ether group (—O—).
Moreover, this monocycloalkane may have a C1-C5 alkyl group, a fluorine atom, or a C1-C5 fluorinated alkyl group as a substituent.
Examples of R ²² constituting such an aliphatic monocyclic group include a linear alkylene group in which an ether group (—O—) may be interposed between carbon atoms.

Specific examples of the structural unit represented by the formula (a1-0-11) include the formulas (a1-1-16) to (a1-1-23), (a1-1-27), and (a1-1 -31). Among these, the formulas (a1-1-16) to (a1-1-17), (a1-1-20) to (a1-1-23), (a1-1-27), (a1-1-1- The structural unit represented by the following (a1-1-02) including the structural unit represented by 31) is preferable. Moreover, the structural unit represented by the following (a1-1-02 ′) is also preferable.
In each formula, h is preferably 1 or 2.

［式中、Ｒ、Ｒ^２１はそれぞれ前記と同じであり、ｈは１〜４の整数である。］

[Wherein, R and R ²¹ are the same as defined above, and h is an integer of 1 to 4, respectively. ]

In formula (a1-0-12), as the branched alkyl group for R ²³ , the branched alkyl group described for the alkyl group for R ¹⁴ in formulas (1-1) to (1-9) above. Examples thereof are the same as those described above, and an isopropyl group is most preferable.
R ²⁴ is, the aliphatic polycyclic group formed together with the carbon atom to which R ²⁴ is bonded, the same aliphatic cyclic groups as those in the aforementioned tertiary alkyl ester-type acid dissociable group, polycyclic group The thing similar to what is is mentioned.
Specific examples of the structural unit represented by the formula (a1-0-12) include those represented by the formulas (a1-1-26) and (a1-1-28) to (a1-1-30). Units are listed.
As the structural unit represented by the formula (a1-0-12), those in which R ²⁴ is an aliphatic polycyclic group formed together with the carbon atom to which R ²⁴ is bonded are preferably a 2-adamantyl group, The structural unit represented by the formula (a1-1-26) is preferable.

In formula (a1-0-13), R and R ²⁴ are the same as defined above.
Examples of the linear alkyl group for R ²⁵ include the same linear alkyl groups as those described above for the alkyl group for R ^{14 in} the formulas (1-1) to (1-9), and methyl Most preferred are groups or ethyl groups.
Specific examples of the structural unit represented by formula (a1-0-13) include formulas (a1-1-1) to (a1-1-3) exemplified as specific examples of general formula (a1-1). ), Structural units represented by (a1-1-7) to (a1-1-15).
As the structural unit represented by the formula (a1-0-13), those in which R ²⁴ is an aliphatic polycyclic group formed together with the carbon atom to which R ²⁴ is bonded are preferably a 2-adamantyl group, The structural unit represented by the formula (a1-1-1) or (a1-1-2) is preferable.

Examples of the structural unit represented by the formula (a1-0-2) include the structural unit represented by the formula (a1-3) or (a1-4), and particularly represented by the formula (a1-3). Are preferred.
As the structural unit represented by the formula (a1-0-2), in particular, Y ² in the formula is a group represented by the formula —Y ²¹ —O—Y ²² —, or the formula — [Y ²¹ —C _{(= O) -O] m '} -Y 22 - group represented by or the formula ^{-Y 21 -O-C (= O} ) -Y 22, - what is a group represented by are preferred.
Preferred examples of the structural unit include a structural unit represented by the following general formula (a1-3-01); a structural unit represented by the following general formula (a1-3-02); 3-03) and the like.

［式中、Ｒは前記と同じであり、Ｒ^１３は水素原子またはメチル基であり、Ｒ^１４はアルキル基であり、ｙは１〜１０の整数であり、ｎ’は０〜３の整数である。］

[Wherein, R is the same as above, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is an alkyl group, y is an integer of 1 to 10, and n ′ is an integer of 0 to 3] is there. ]

［式中、Ｒは前記と同じであり、Ｙ^２’およびＹ^２”はそれぞれ独立して２価の連結基であり、Ｘ’は酸解離性基であり、ｗは０〜３の整数である。］

[Wherein, R is the same as defined above, Y ² ′ and Y ² ″ are each independently a divalent linking group, X ′ is an acid-dissociable group, and w is an integer of 0 to 3] is there.]

In formulas (a1-3-01) to (a1-3-02), R ¹³ is preferably a hydrogen atom.
R ¹⁴ is the same as ^{R 14} in the formula (1-1) to (1-9).
y is preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and most preferably 1 or 2.
n ′ is preferably 1 or 2, and most preferably 2.
Specific examples of the structural unit represented by the formula (a1-3-01) include structural units represented by the formulas (a1-3-25) to (a1-3-26).
Specific examples of the structural unit represented by the formula (a1-3-02) include structural units represented by the formulas (a1-3-27) to (a1-3-28).

In formula (a1-3-03), examples of the divalent linking group for Y ² ′ and Y ² ″ include the same groups as those described above for Y ² in formula (a1-3).
Y ² ′ is preferably a divalent hydrocarbon group which may have a substituent, more preferably a linear aliphatic hydrocarbon group, and even more preferably a linear alkylene group. Among these, a linear alkylene group having 1 to 5 carbon atoms is preferable, and a methylene group and an ethylene group are most preferable.
Y ² ″ is preferably a divalent hydrocarbon group which may have a substituent, more preferably a linear aliphatic hydrocarbon group, and still more preferably a linear alkylene group. A linear alkylene group of 1 to 5 is preferable, and a methylene group and an ethylene group are most preferable.
Examples of the acid dissociable group in X ′ include the same groups as described above, and are preferably tertiary alkyl ester-type acid dissociable groups. In addition, a group in which a substituent is bonded to a carbon atom bonded to an atom adjacent to the acid dissociable group to form a tertiary carbon atom is more preferable. Preferred are the groups
w is an integer of 0 to 3, and w is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 1.
As the structural unit represented by the formula (a1-3-03), a structural unit represented by the following general formula (a1-3-03-1) or (a1-3-03-2) is preferable. The structural unit represented by the formula (a1-3-03-1) is preferable.

［式中、ＲおよびＲ^１４はそれぞれ前記と同じであり、ａ’は１〜１０の整数であり、ｂ’は１〜１０の整数であり、ｔは０〜３の整数である。］

[Wherein, R and R ¹⁴ are the same as defined above, a ′ is an integer of 1 to 10, b ′ is an integer of 1 to 10, and t is an integer of 0 to 3, respectively. ]

In formulas (a1-3-03-1) to (a1-3-03-2), a ′ is preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and particularly preferably 1 or 2.
b ′ is preferably an integer of 1 to 8, more preferably an integer of 1 to 5, and particularly preferably 1 or 2.
t is preferably an integer of 1 to 3, and 1 or 2 is particularly preferable.
Specific examples of the structural unit represented by formula (a1-3-03-1) or (a1-3-03-2) include those represented by formulas (a1-3-29) to (a1-3-32). The structural unit represented is mentioned.

{Structural unit (a12)}
In the structural unit (a12), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the benzene ring may be substituted with a substituent other than a hydroxyl group. It is a structural unit in which a hydrogen atom of a hydroxyl group of a structural unit derived from styrene is substituted with an acid dissociable group or a substituent containing an acid dissociable group.
Examples of the acid dissociable group for substituting the hydrogen atom of the hydroxyl group include the same groups as those described above, preferably a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group, and an acetal type acid dissociable group is More preferred.
Examples of the substituent containing an acid dissociable group include a group composed of an acid dissociable group and a divalent linking group. Examples of the divalent linking group include those similar to the divalent linking group in L ⁰¹ in the general formula (I-1) mentioned in the description of the component (C), and in particular, the acid-dissociable group side. A group in which the terminal structure is a carbonyloxy group is preferred. In this case, it is preferable that an acid dissociable group is bonded to the oxygen atom (—O—) of the carbonyloxy group.
Examples of the substituent containing an acid dissociable group include a group represented by R ¹¹ ′ —O—C (═O) — and a group represented by R ¹¹ ′ —O—C (═O) —R ¹² ′ —. Is preferred. In the formula, R ¹¹ ′ is an acid dissociable group, and R ¹² ′ is a linear or branched alkylene group.
The acid dissociable group for R ¹¹ ′ is preferably a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group, more preferably a tertiary alkyl ester type acid dissociable group. As a preferable example of the tertiary alkyl ester type acid dissociable group, the aliphatic branched acid dissociable group represented by the above-described —C (R ⁷¹ ) (R ⁷² ) (R ⁷³ ), the formula (1- Examples include groups represented by 1) to (1-9), groups represented by formulas (2-1) to (2-6), and the like.
Examples of the alkylene group for R ¹² ′ include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, and a 1,1-dimethylethylene group. R ¹² ′ is preferably a linear alkylene group.
Specifically, as the structural unit (a12), for example, in the general formula (U-3) mentioned in the description of the component (C),-(OX ^c ) _px , which is bonded to the benzene ring, is an integer in which px is 1 to 3 And at least one of ^Xc is an acid-dissociable group or a substituent containing an acid-dissociable group. When px is 2 or 3, the plurality of X ^c may be the same or different. For example, one may be an acid-dissociable group or a substituent containing an acid-dissociable group, and the other one or two may be a hydrogen atom.

{Structural unit (a13)}
In the structural unit (a13), a hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring may be substituted with a substituent other than a hydroxyl group. It is a structural unit formed by replacing the hydrogen atom of the hydroxyl group of a structural unit derived from (hydroxynaphthalene) with an acid-dissociable group or a substituent containing an acid-dissociable group.
In the structural unit (a13), examples of the acid dissociable group for substituting a hydrogen atom of a hydroxyl group and the substituent containing an acid dissociable group include the same groups as those described above for the structural unit (a12). It is done.
Specifically, as the structural unit (a13), for example, in the general formula (U-4) mentioned in the description of the component (C), _x of — (OX ^d ) _x bonded to the benzene ring is an integer of 1 to 3. And at least one of X ^d is an acid dissociable group or a substituent containing an acid dissociable group. When x is 2 or 3, the plurality of X ^d may be the same or different. For example, one may be an acid-dissociable group or a substituent containing an acid-dissociable group, and the other one or two may be a hydrogen atom.

As the structural unit (a1) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
In the component (A1), the proportion of the structural unit (a1) is preferably from 15 to 70 mol%, more preferably from 15 to 60 mol%, more preferably from 20 to 55 mol%, based on all the structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when a resist composition is formed, and lithography properties such as sensitivity, resolution, and pattern shape are improved. Moreover, the balance with another structural unit can be taken by making it below an upper limit.

(Structural unit (a2))
The component (A1) preferably further has a structural unit (a2) containing a —SO ₂ — containing cyclic group or a lactone-containing cyclic group in addition to the structural units (a0) and (a1).
The —SO ₂ — containing cyclic group or lactone cyclic group of the structural unit (a2) is effective for enhancing the adhesion of the resist film to the substrate when the component (A1) is used for forming the resist film. Is. Moreover, it is effective in the alkali development process in that the affinity with a developer containing water such as an alkali developer is improved.
In addition, when the structural unit (a0) or (a1) includes a —SO ₂ — containing cyclic group or a lactone-containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2). Such a structural unit corresponds to the structural unit (a0) or (a1) and does not correspond to the structural unit (a2).

Here, the “—SO ₂ -containing cyclic group” refers to a cyclic group containing a ring containing —SO ₂ — in the ring skeleton, specifically, a sulfur atom in —SO ₂ — ( S) is a cyclic group that forms part of the ring skeleton of the cyclic group. The ring containing —SO ₂ — in the ring skeleton is counted as the first ring, and when it is only the ring, it is a monocyclic group, and when it has another ring structure, it is a polycyclic group regardless of the structure. Called. The —SO ₂ — containing cyclic group may be monocyclic or polycyclic.
-SO ₂ - containing cyclic group, in particular, -O-SO ₂ - within the ring skeleton cyclic group containing, i.e. -O-SO ₂ - -O-S- medium is a part of the ring skeleton It is preferably a cyclic group containing a sultone ring to be formed.
The —SO ₂ — containing cyclic group preferably has 3 to 30 carbon atoms, more preferably 4 to 20 carbon atoms, still more preferably 4 to 15 carbon atoms, and particularly preferably 4 to 12 carbon atoms. preferable. However, the carbon number is the number of carbon atoms constituting the ring skeleton, and does not include the carbon number in the substituent.
The —SO ₂ — containing cyclic group may be an —SO ₂ — containing aliphatic cyclic group or an —SO ₂ — containing aromatic cyclic group. Preferably -SO ₂ - containing aliphatic cyclic group.
The —SO ₂ -containing aliphatic cyclic group includes at least a hydrogen atom from an aliphatic hydrocarbon ring in which a part of carbon atoms constituting the ring skeleton is substituted with —SO ₂ — or —O—SO ₂ —. One group is excluded. More specifically, a group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring in which —CH ₂ — constituting the ring skeleton is substituted with —SO ₂ —, —CH ₂ — constituting the ring And a group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring in which CH ₂ — is substituted with —O—SO ₂ —.
The alicyclic hydrocarbon ring preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon ring may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms are removed from a monocycloalkane having 3 to 6 carbon atoms. Examples of the monocycloalkane include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon ring, a group in which two hydrogen atoms are removed from a polycycloalkane having 7 to 12 carbon atoms is preferable. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane. , Tricyclodecane, tetracyclododecane and the like.

The —SO ₂ — containing cyclic group may have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), —COOR ″, —OC (═O) R ″, a hydroxyalkyl group, a cyano group, and the like. Is mentioned.
The alkyl group as the substituent is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and a hexyl group. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the group couple | bonded with the oxygen atom (-O-) to the alkyl group quoted as the alkyl group as the said substituent is mentioned.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group for the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
Examples of the halogenated alkyl group as the substituent include a group in which part or all of the hydrogen atoms of the alkyl group mentioned as the alkyl group as the substituent are substituted with the halogen atom. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.
R ″ in —COOR ″ and —OC (═O) R ″ is a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms.
When R ″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. preferable.
When R ″ is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a fluorine atom Alternatively, one or more hydrogen atoms are removed from a polycycloalkane such as a monocycloalkane, bicycloalkane, tricycloalkane, or tetracycloalkane, which may or may not be substituted with a fluorinated alkyl group. More specifically, one or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane, or a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Group.
The hydroxyalkyl group as the substituent is preferably one having 1 to 6 carbon atoms. Specifically, at least one of the hydrogen atoms of the alkyl group mentioned as the alkyl group as the substituent is substituted with a hydroxyl group. Group.
More specifically, examples of the —SO ₂ -containing cyclic group include groups represented by the following general formulas (3-1) to (3-4).

［式中、Ａ’は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｚは０〜２の整数であり、Ｒ^２７はアルキル基、アルコキシ基、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり、Ｒ”は水素原子またはアルキル基である。］

[In the formula, A ′ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, z is an integer of 0 to 2, and R ²⁷ is an alkyl group. , An alkoxy group, a halogenated alkyl group, a hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group, and R ″ is a hydrogen atom or an alkyl group.]

In the general formulas (3-1) to (3-4), A ′ represents an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (—O—) or a sulfur atom (—S—), An oxygen atom or a sulfur atom.
The alkylene group having 1 to 5 carbon atoms in A ′ is preferably a linear or branched alkylene group, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.
When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which —O— or —S— is interposed between the terminal or carbon atoms of the alkylene group, such as —O—CH _{2. -, - CH 2 -O-CH} 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like.
A ′ is preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.
z may be any of 0 to 2, and is most preferably 0.
When z is 2, the plurality of R ²⁷ may be the same or different.
As the alkyl group, alkoxy group, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in R ²⁷ , the —SO ₂ — containing cyclic group has the above-mentioned, respectively. And the same alkyl groups, alkoxy groups, halogenated alkyl groups, —COOR ″, —OC (═O) R ″, and hydroxyalkyl groups as those which may be substituted.
Below, the specific cyclic group represented by the said general formula (3-1)-(3-4) is illustrated. In the formula, “Ac” represents an acetyl group.

Among the above, the —SO ₂ -containing cyclic group is preferably a group represented by the general formula (3-1), and the chemical formulas (3-1-1), (3-1-18), ( It is more preferable to use at least one selected from the group consisting of groups represented by any of 3-3-1) and (3-4-1), and represented by the chemical formula (3-1-1). Are most preferred.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C (═O) — in the ring skeleton. The lactone ring is counted as the first ring. When only the lactone ring is present, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone cyclic group in the structural unit (a2) is not particularly limited, and any one can be used. Specifically, the lactone-containing monocyclic group is a group obtained by removing one hydrogen atom from a 4- to 6-membered ring lactone, such as a group obtained by removing one hydrogen atom from β-propionolactone, or γ-butyrolactone. Examples thereof include a group in which one hydrogen atom has been removed and a group in which one hydrogen atom has been removed from δ-valerolactone. Examples of the lactone-containing polycyclic group include groups in which one hydrogen atom has been removed from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring.

The structural unit (a2) is not particularly limited as long as it has a —SO ₂ — containing cyclic group or a lactone-containing cyclic group, but the hydrogen atom bonded to the α-position carbon atom is A structural unit derived from an acrylate ester optionally substituted with a substituent, including a structural unit (a2 ^S ) containing a —SO ₂ -containing cyclic group, and a hydrogen atom bonded to the α-position carbon atom; At least one structural unit selected from the group consisting of a structural unit (a2 ^L ) that is a structural unit derived from an acrylate ester that may be substituted with a substituent and that contains a lactone-containing cyclic group is preferred.

-Structural unit (a2 ^S ):
More specifically, examples of the structural unit (a2 ^S ) include structural units represented by general formula (a2-0) shown below.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり、Ｒ^２８は−ＳＯ_２−含有環式基であり、Ｒ^２９は単結合または２価の連結基である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, R ²⁸ represents a —SO ₂ — containing cyclic group, and R ²⁹ represents a single bond. Or it is a bivalent coupling group. ]

In formula (a2-0), R is the same as defined above.
R ²⁸ is the same as the —SO ₂ — containing cyclic group mentioned above.
R ²⁹ may be a single bond or a divalent linking group. Since it is excellent in the effect of this invention, it is preferable that it is a bivalent coupling group.
The divalent linking group in R ²⁹ is not particularly limited, and examples thereof include the same divalent linking groups as those in L ⁰¹ in the general formula (I-1) mentioned in the description of the component (C). Can be mentioned. Among these, those containing an alkylene group or an ester bond (—C (═O) —O—) are preferable.
The alkylene group is preferably a linear or branched alkylene group. Specifically, the same as the linear alkylene group and the branched alkylene group mentioned as the aliphatic hydrocarbon group for Y ² can be used.
As the divalent linking group containing an ester bond, in particular, the general formula: —R ³⁰ —C (═O) —O— [wherein R ³⁰ is a divalent linking group. ] Is preferable. That is, the structural unit (a2 ^S ) is preferably a structural unit represented by the following general formula (a2-0-1).

［式中、ＲおよびＲ^２８はそれぞれ前記と同様であり、Ｒ^３０は２価の連結基である。］

[Wherein, R and R ²⁸ are the same as defined above, and R ³⁰ represents a divalent linking group. ]

R ³⁰ is not particularly limited, and examples thereof include those similar to the divalent linking group in L ⁰¹ in the general formula (I-1) mentioned in the description of the component (C).
As the divalent linking group for R ^30, a linear or branched alkylene group, an aliphatic hydrocarbon group containing a ring in the structure, or a divalent linking group containing a hetero atom is preferable. Alternatively, a branched alkylene group or a divalent linking group containing an oxygen atom as a hetero atom is preferable.
As the linear alkylene group, a methylene group or an ethylene group is preferable, and a methylene group is particularly preferable.
As the branched alkylene group, an alkylmethylene group or an alkylethylene group is preferable, and —CH (CH ₃ ) —, —C (CH ₃ ) ₂ — or —C (CH ₃ ) ₂ CH ₂ — is particularly preferable.
The divalent linking group containing an oxygen atom is preferably a divalent linking group containing an ether bond or an ester bond, and the above-described —Y ²¹ —O—Y ²² —, — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (═O) —Y ²² — is more preferable. Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, and m ′ is an integer of 0 to 3. Among them, —Y ²¹ —O—C (═O) —Y ²² — is preferable, and a group represented by — (CH ₂ ) _c —O—C (═O) — (CH ₂ ) _d — is particularly preferable. . c is an integer of 1 to 5, and 1 or 2 is preferable. d is an integer of 1-5, and 1 or 2 is preferable.

As the structural unit (a2 ^S ), a structural unit represented by general formula (a2-0-11) or (a2-0-12) shown below is particularly desirable, and represented by formula (a2-0-12). A structural unit is more preferable.

［式中、Ｒ、Ａ’、Ｒ^２７、ｚおよびＲ^３０はそれぞれ前記と同じである。］

[Wherein, R, A ′, R ²⁷ , z and R ³⁰ are the same as defined above. ]

In formula (a2-0-11), A ′ is preferably a methylene group, an oxygen atom (—O—) or a sulfur atom (—S—).
R ³⁰ is preferably a linear or branched alkylene group or a divalent linking group containing an oxygen atom. As the linear or branched alkylene group and the divalent linking group containing an oxygen atom in R ^30, the linear or branched alkylene group mentioned above and a divalent linking group containing an oxygen atom are mentioned. Examples are the same as the linking group.
As the structural unit represented by the formula (a2-0-12), a structural unit represented by the following general formula (a2-0-12a) or (a2-0-12b) is particularly preferable.

［式中、ＲおよびＡ’はそれぞれ前記と同じであり、ｃ〜ｅはそれぞれ独立に１〜３の整数である。］

[Wherein, R and A ′ are the same as defined above, and c to e are each independently an integer of 1 to 3.] ]

-Structural unit (a2 ^L ):
Examples of the structural unit (a2 ^L ) include those obtained by substituting R ²⁸ in the general formula (a2-0) with a lactone-containing cyclic group, and more specifically, the following general formula (a2- The structural unit represented by 1)-(a2-5) is mentioned.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基であり；Ｒ’はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、酸素原子（＝Ｏ）、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり、Ｒ”は水素原子またはアルキル基であり；Ｒ^２９は単結合または２価の連結基であり、ｓ”は０〜２の整数であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり；ｍは０または１である。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; R ′ is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, or a halogen atom. alkyl group, a hydroxyl group, an oxygen atom (= O), - COOR " , - OC (= O) R", a hydroxyalkyl group or a cyano group, R "represents a hydrogen atom or an alkyl ^{group; R 29} is a single A bond or a divalent linking group, s "is an integer of 0 to 2; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom. Yes; m is 0 or 1.]

R in the general formulas (a2-1) to (a2-5) is the same as described above.
The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group of R ′ each have a —SO ₂ — containing cyclic group. Alkyl groups, alkoxy groups, halogen atoms, halogenated alkyl groups, —COOR ″, —OC (═O) R ″, hydroxyalkyl groups, —COOR ″, —OC (═O) R, which may be enumerated as substituents. Examples thereof include “(R” is the same as above).
Examples of A ″ include the same as A ′ in the general formula (3-1). A ″ represents an alkylene group having 1 to 5 carbon atoms, an oxygen atom (—O—) or a sulfur atom (— S-) is preferable, and an alkylene group having 1 to 5 carbon atoms or -O- is more preferable. The alkylene group having 1 to 5 carbon atoms is more preferably a methylene group or dimethylmethylene group, and most preferably a methylene group.
R ²⁹ is the same as ^{R 29} in the aforementioned general formula (a2-0).
In formula (a2-1), s ″ is preferably 1 to 2.
Specific examples of the structural units represented by the general formulas (a2-1) to (a2-5) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

As the structural unit (a2 ^L ), at least one selected from the group consisting of structural units represented by the general formulas (a2-1) to (a2-5) is preferable, and the general formula (a2-1) to More preferably, at least one selected from the group consisting of structural units represented by (a2-3) is selected from the group consisting of structural units represented by the general formula (a2-1) or (a2-3) Particularly preferred is at least one of the above.
Among them, the formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-7), (a2-2-12), (a2-2-2-) 14), (a2-3-1), at least one selected from the group consisting of structural units represented by (a2-3-5) is preferred.

Moreover, as the structural unit (a2 ^L ), structural units represented by the following formulas (a2-6) to (a2-7) are also preferable.

［式中、Ｒ、Ｒ^２９は前記同様である。］

[Wherein, R and R ²⁹ are the same as defined above. ]

The structural unit (a2) contained in the component (A1) may be one type or two or more types. For example, as the structural unit (a2), only the structural unit (a2 ^S ) may be used, or only the structural unit (a2 ^L ) may be used, or they may be used in combination. As the structural unit (a2 ^S ) or the structural unit (a2 ^L ), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a2) is preferably 1 to 80 mol%, and preferably 10 to 70 mol%, based on the total of all structural units constituting the component (A1). Is more preferable, it is more preferable that it is 10-65 mol%, and 10-60 mol% is especially preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by setting it to the upper limit value or less, it is possible to balance with other structural units, such as various kinds of DOF, CDU, etc. The lithography characteristics and pattern shape of the film are improved.

(Structural unit (a3))
The component (A1) further has a structural unit (a3) containing a polar group in addition to the structural units (a0) and (a1) or in addition to the structural units (a0), (a1) and (a2). May be. When the component (A1) has the structural unit (a3), the polarity of the component (A1) after exposure is further improved. The improvement in polarity contributes to an improvement in resolution and the like, particularly in the case of an alkali development process.
Examples of the polar group include —OH, —COOH, —CN, —SO ₂ NH ₂ , —CONH ₂ , and the like. Those containing —COOH also include structural units of (α-substituted) acrylic acid.
The structural unit (a3) is preferably a structural unit containing a hydrocarbon group in which a part of hydrogen atoms is substituted with a polar group. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Of these, the hydrocarbon group is more preferably an aliphatic hydrocarbon group.
Examples of the aliphatic hydrocarbon group in the hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and an aliphatic cyclic group (monocyclic group, polycyclic group). Cyclic group).
As the aliphatic cyclic group (monocyclic group, polycyclic group), for example, a resin for a resist composition for ArF excimer laser can be appropriately selected from those proposed. The aliphatic cyclic group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. Specifically, for example, a group in which two or more hydrogen atoms have been removed from a monocycloalkane; a group in which two or more hydrogen atoms have been removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which two or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane; two or more groups from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom. The aliphatic cyclic group may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, and a fluorinated alkyl group having 1 to 5 carbon atoms.

The aromatic hydrocarbon group in the hydrocarbon group is a hydrocarbon group having an aromatic ring, preferably having 5 to 30 carbon atoms, more preferably 6 to 20, still more preferably 6 to 15 and 6 Is most preferred. However, the carbon number does not include the carbon number in the substituent. The aromatic ring of the aromatic hydrocarbon group is the same as described above, and specifically includes benzene, naphthalene, anthracene, phenanthrene and the like.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two or more hydrogen atoms from the aromatic ring (arylene group); an aromatic compound containing two or more aromatic rings (for example, biphenyl, fluorene, etc.) A group in which two atoms are removed; a group in which one of the hydrogen atoms in the aromatic ring (aryl group) is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl) Group, a group obtained by further removing one hydrogen atom from an aryl group in an arylalkyl group such as a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.
The aromatic hydrocarbon group may or may not have a substituent. For example, the hydrogen atom bonded to the aromatic ring of the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, a halogen atom, and a halogenated alkyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the halogen atom as a substituent for the aromatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

  As the structural unit (a3), structural units represented by general formula (a3-1) shown below are preferred.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｐ^０は−Ｃ（＝Ｏ）−Ｏ−、−Ｃ（＝Ｏ）−ＮＲ^０−（Ｒ^０は水素原子又は炭素数１〜５のアルキル基である）又は単結合である。Ｗ^０は−ＣＯＯＨ、または置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する炭化水素基、又は、−ＣＯＮＨＣＯ−Ｒ^ａ３（Ｒ^ａ３は炭化水素基）であり、任意の位置に酸素原子又は硫黄原子を有していてもよい。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. P ⁰ is —C (═O) —O—, —C (═O) —NR ⁰ — (R ⁰ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond. W ⁰ is —COOH, a hydrocarbon group having at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ and —CONH ₂ as a substituent, or —CONHCO— R ^a3 (R ^a3 is a hydrocarbon group), which may have an oxygen atom or a sulfur atom at an arbitrary position. ]

In the formula (a3-1), the alkyl group of R is preferably a linear or branched alkyl group, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, Examples include isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like.
Examples of the halogenated alkyl group for R include groups in which some or all of the hydrogen atoms of the aforementioned R alkyl group have been substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.
In Formula (a3-1), P ⁰ is —C (═O) —O—, —C (═O) —NR ⁰ — (R ⁰ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ) Or a single bond. The alkyl group for R ⁰ is the same as the alkyl group for R.

In the formula (a3-1), W ⁰ is a hydrocarbon group having at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ and —CONH ₂ as a substituent. or, ^{-CONHCO-R a3 (R} a3 is a hydrocarbon group), and may have an oxygen atom or a sulfur atom in any position.
The “hydrocarbon group having a substituent” means that at least a part of hydrogen atoms bonded to the hydrocarbon group is substituted with a substituent.
The hydrocarbon group for W ⁰ or R ^a3 may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
Examples of the aliphatic hydrocarbon group for W ⁰ or R ^a3 include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group), an aliphatic cyclic group (monocyclic group, A polycyclic group), and the description thereof is the same as described above.
The aromatic hydrocarbon group for W ⁰ or R ^a3 is a hydrocarbon group having at least one aromatic ring, and this description is the same as described above.

However, W ⁰ may have an oxygen atom or a sulfur atom at an arbitrary position. The phrase “may have an oxygen atom or a sulfur atom at any position” means a carbon atom constituting a hydrocarbon group or a hydrocarbon group having a substituent (including the carbon atom of the substituent portion). ) May be substituted with an oxygen atom or a sulfur atom, or a hydrogen atom bonded to a hydrocarbon group may be substituted with an oxygen atom or a sulfur atom.
The following is an example of W ⁰ having an oxygen atom (O) at an arbitrary position.

［式中、Ｗ^００は炭化水素基であり、Ｒ^ｍは炭素数１〜５のアルキレン基である。］

[Wherein, W ⁰⁰ is a hydrocarbon group, and R ^m is an alkylene group having 1 to 5 carbon atoms. ]

In the above formula, W ⁰⁰ is a hydrocarbon group, and examples thereof include the same as W ⁰ in the formula (a3-1). W ⁰⁰ is preferably an aliphatic hydrocarbon group, more preferably an aliphatic cyclic group (monocyclic group or polycyclic group).
R ^m is preferably linear or branched, preferably an alkylene group having 1 to 3 carbon atoms, and more preferably a methylene group or an ethylene group.

More preferable examples of the structural unit (a3) include more specifically structural units derived from (α-substituted) acrylic acid esters, any of the following general formulas (a3-11) to (a3-13): The structural unit etc. which are represented by these are mentioned. Examples of the structural unit derived from the (α-substituted) acrylate ester include a structural unit in which P ⁰ in the formula (a3-1) is a single bond and W ⁰ is —COOH.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｗ^０１は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する芳香族炭化水素基である。Ｐ^０２及びＰ^０３はそれぞれ−Ｃ（＝Ｏ）−Ｏ−、−Ｃ（＝Ｏ）−ＮＲ^０−（Ｒ^０は水素原子又は炭素数１〜５のアルキル基である）又は単結合である。Ｗ^０２は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する環状の炭化水素基、又は、−ＣＯＮＨＣＯ−Ｒ^ａ３２（Ｒ^ａ３２は環状の炭化水素基）であり、任意の位置に酸素原子又は硫黄原子を有していてもよい。Ｗ^０３は置換基として−ＯＨ、−ＣＯＯＨ、−ＣＮ、−ＳＯ_２ＮＨ_２及び−ＣＯＮＨ_２からなる群より選択される少なくとも一種の基を有する鎖状の炭化水素基、又は、−ＣＯＮＨＣＯ−Ｒ^ａ３３（Ｒ^ａ３３は鎖状の炭化水素基）である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. W ⁰¹ is an aromatic hydrocarbon group having at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ and —CONH ₂ as a substituent. P ⁰² and P ⁰³ are —C (═O) —O—, —C (═O) —NR ⁰ — (R ⁰ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond, respectively. . W ⁰² is -OH as a substituent, -COOH, -CN, cyclic hydrocarbon radical having at least one group selected from the group consisting of _-SO 2 NH ₂ and -CONH _2, or, ^{-CONHCO-R a32} (R ^a32 is a cyclic hydrocarbon group) and may have an oxygen atom or a sulfur atom at an arbitrary position. W ⁰³ is a chain hydrocarbon group having at least one group selected from the group consisting of —OH, —COOH, —CN, —SO ₂ NH ₂ and —CONH ₂ as a substituent, or —CONHCO—R ^a33 (R ^a33 is a chained hydrocarbon group). ]

[Structural Unit Represented by General Formula (a3-11)]
In the formula (a3-11), R is the same as described for R in the formula (a3-1).
The aromatic hydrocarbon group for W ⁰¹ is the same as that described for the aromatic hydrocarbon group for W ⁰ in formula (a3-1).
Specific examples of preferable structural units represented by general formula (a3-11) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[Structural Unit Represented by General Formula (a3-12)]
In the formula (a3-12), R is the same as described for R in the formula (a3-1).
P ⁰² is —C (═O) —O—, —C (═O) —NR ⁰ — (R ⁰ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond, (═O) —O— or a single bond is preferred. The alkyl group for R ⁰ is the same as the alkyl group for R.
The cyclic hydrocarbon group in W ⁰² or R ^a32 is an aliphatic cyclic group (monocyclic group or polycyclic group) exemplified in the description of W ⁰ in the formula (a3-1), aromatic The same thing as each group hydrocarbon group is mentioned.
W ⁰² or R ^a32 may have an oxygen atom or a sulfur atom at an arbitrary position, and this description is the same as the description of W ⁰ in the formula (a3-1).
Specific examples of preferred structural units represented by general formula (a3-12) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[Structural Unit Represented by General Formula (a3-13)]
In the formula (a3-13), R is the same as described for R in the formula (a3-1).
P ⁰³ is —C (═O) —O—, —C (═O) —NR ⁰ — (R ⁰ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond, (═O) —O— or a single bond is preferred. The alkyl group for R ⁰ is the same as the alkyl group for R.
The chain hydrocarbon group for W ⁰³ or R ^a33 preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and still more preferably 1 to 3 carbon atoms.
The chain hydrocarbon group in W ⁰³ or R ^a33 may further have a substituent (a) other than —OH, —COOH, —CN, —SO ₂ NH _2, and —CONH ₂ . Examples of the substituent (a) include an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group, polycyclic group), a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and the like. Can be mentioned. The number of carbon atoms of the aliphatic cyclic group (monocyclic group or polycyclic group) in the substituent (a) is preferably 3 to 30, more preferably 5 to 30, and further preferably 5 to 20 Preferably, 6-15 is especially preferable, and 6-12 is the most preferable. Specifically, for example, a group in which two or more hydrogen atoms have been removed from a monocycloalkane; a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which two or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane; one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.
Further, straight-chain hydrocarbon group for W ^03, as in the structural unit represented by the following general formula as an example (a3-13-a), may have a plurality of substituents (a), A plurality of substituents (a) may be bonded to each other to form a ring.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基である。Ｒ^ａ１及びＲ^ａ２はそれぞれ独立に炭素数１〜５のアルキル基、脂肪族環式基（単環式基、多環式基）、フッ素原子、又は炭素数１〜５のフッ素化アルキル基である。但し、Ｒ^ａ１とＲ^ａ２とが相互に結合して環を形成してもよい。ｑ^０は１〜４の整数である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R ^a1 and R ^a2 are each independently an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group or polycyclic group), a fluorine atom, or a fluorinated alkyl group having 1 to 5 carbon atoms. is there. However, R ^a1 and R ^a2 may be bonded to each other to form a ring. q ⁰ is an integer of 1 to 4. ]

In the formula (a3-13-a), R is the same as described for R in the formula (a3-1).
The aliphatic cyclic group (monocyclic group or polycyclic group) in R ^a1 and R ^a2 is the same as the aliphatic cyclic group (monocyclic group or polycyclic group) in the substituent (a). is there.
R ^a1 and R ^a2 may be bonded to each other to form a ring. In this ^case, a ^{R a1,} and ^{R a2,} cyclic group is formed by the carbon atoms to which the ^{R a1} and ^{R a2} are bonded together. The cyclic group may be a monocyclic group or a polycyclic group. Specifically, an aliphatic cyclic group (monocyclic group, Examples thereof include groups in which one or more hydrogen atoms have been removed from the monocycloalkane or polycycloalkane exemplified in the description of the polycyclic group).
q ⁰ is preferably 1 or 2, and more preferably 1.

Specific examples of preferable structural units represented by general formula (a3-13) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a3) contained in the component (A1) may be one type or two or more types.
In the component (A1), the proportion of the structural unit (a3) is preferably 0 to 85 mol%, more preferably 0 to 80 mol%, based on all structural units constituting the component (A1). By setting the proportion of the structural unit (a3) to be equal to or higher than the lower limit value, the effects (resolution, lithography characteristics, pattern shape improvement effect) due to the inclusion of the structural unit (a3) can be sufficiently obtained. This makes it easier to balance with other structural units.

(Structural unit (a4))
The component (A1) may further have a structural unit (a4) containing an acid non-dissociable cyclic group as necessary. When the component (A1) has the structural unit (a4), the dry etching resistance of the formed resist pattern is improved. Moreover, the hydrophobicity of (A1) component increases. The improvement in hydrophobicity contributes to the improvement in resolution, resist pattern shape, etc., particularly in the case of organic solvent development.
The “acid non-dissociable cyclic group” in the structural unit (a4) means that the acid acts when an acid is generated from the structural unit (a0) or an arbitrary acid generator component (B) described later by exposure. However, the cyclic group remains in the structural unit as it is without dissociating.
As the structural unit (a4), a structural unit obtained by substituting the acid dissociable group in the structural unit (a1) with an acid non-dissociable cyclic group can be given. Among them, a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and including a non-acid-dissociable aliphatic cyclic group ( a41), a structural unit derived from styrene in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent The structural unit (a43) derived from vinyl naphthalene which may be present is preferred.

As the non-acid dissociable aliphatic cyclic group in the structural unit (a41), for example, an atom adjacent to the aliphatic cyclic group (for example, —O— in —C (═O) —O—) is bonded. A monovalent aliphatic cyclic group in which a substituent (atom or group other than a hydrogen atom) is not bonded to a carbon atom, one of the hydrogen atoms of a primary or secondary alkyl group is a monovalent aliphatic cyclic group And a group substituted with a group.
The monovalent aliphatic cyclic group is not particularly limited as long as it is non-acid dissociable, and is used as a resin component of a resist composition such as for ArF excimer laser and for KrF excimer laser (preferably for ArF excimer laser). Many known in the art can be used. The aliphatic cyclic group may be saturated, unsaturated, or saturated.
The aliphatic cyclic group may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and an oxygen atom (= O).
The basic ring structure excluding the substituent of the aliphatic cyclic group is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The hydrocarbon group may be either saturated or unsaturated, but is usually preferably saturated.
As the aliphatic cyclic group, those having 3 to 30 carbon atoms are preferable, those having 5 to 30 are more preferable, 5 to 20 are more preferable, 6 to 15 are particularly preferable, and 6 to 12 is most preferable. .
The aliphatic cyclic group may be monocyclic or polycyclic. As the monocyclic aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like. Moreover, a part of carbon atoms constituting the ring of these aliphatic cyclic groups may be substituted with an ether group (—O—).
The aliphatic cyclic group is preferably polycyclic because it is excellent in the above effects. In particular, those having 2 to 4 rings are preferable, and among them, at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group and a norbornyl group is preferable in terms of industrial availability. .

Specific examples of the monovalent aliphatic cyclic group as the non-acid-dissociable aliphatic cyclic group include, for example, an atom adjacent to the aliphatic cyclic group (for example, in —C (═O) —O—). A monovalent aliphatic cyclic group in which a substituent (an atom or group other than a hydrogen atom) is not bonded to a carbon atom bonded to —O—). Specifically, a group in which R ¹⁴ in the groups represented by formulas (1-1) to (1-9) given in the description of the acid dissociable group is substituted with a hydrogen atom; a carbon atom constituting the ring skeleton A group obtained by removing a hydrogen atom from the tertiary carbon atom of a cycloalkane having a tertiary carbon atom formed only by the above;
Examples of the group in which one hydrogen atom of the primary or secondary alkyl group is substituted with a monovalent aliphatic cyclic group include those represented by the formulas (2-1) to (2- And a group in which at least one of R ^{15 and} R ^{16 in} 6) is a hydrogen atom.

As the structural unit (a41), structural units in which the acid dissociable group in the structural unit (a11) is substituted with an acid non-dissociable aliphatic cyclic group can be mentioned, and in the general formula (a1-0-1), A structural unit obtained by substituting X ¹ with a non-acid-dissociable aliphatic polycyclic group, that is, a structural unit represented by the following general formula (a4-0) is preferred, and in particular, the following general formulas (a4-1) to ( The structural unit represented by a4-5) is preferred.

［式中、Ｒは前記と同じであり、Ｒ^４０は酸非解離性の脂肪族多環式基である。］

[Wherein, R is the same as defined above, and R ⁴⁰ represents a non-acid-dissociable aliphatic polycyclic group. ]

［式中、Ｒは前記と同じである。］

[Wherein, R is the same as defined above. ]

Specifically, as the structural unit (a42), for example, in general formula (U-3) mentioned in the description of component (C) above,-(OX ^c ) _px bonded to the benzene ring has a px of 0 Can be mentioned.
Specific examples of the structural unit (a43) include those in which x in-(OX ^d ) _x bonded to the benzene ring is 0 in the general formula (U-4) mentioned in the description of the component (C). Can be mentioned.

The structural unit (a4) contained in the component (A1) may be one type or two or more types.
When the component (A1) contains the structural unit (a4), the proportion of the structural unit (a4) in the component (A1) is 1 to 30 mol relative to the total of all the structural units constituting the component (A1). % Is preferable, 1 to 20 mol% is more preferable, and 5 to 20 mol% is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a4) can be sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

The component (A1) may contain other structural units other than the structural units (a0) to (a4) as long as the effects of the present invention are not impaired.
The other structural units are not particularly limited as long as they are other structural units not classified into the structural units (a0) to (a4) described above. For ArF excimer laser, for KrF excimer laser, for EB, and EUV A number of hitherto known materials that can be used for resist resins such as those for use can be used.

In the present invention, the component (A1) is preferably a copolymer having the structural units (a0) and (a1), and is a copolymer having the structural units (a0), (a1) and (a2). More preferred is a copolymer having structural units (a0), (a1), (a2) and (a3).
Examples of the copolymer having the structural units (a0) and (a1) include a copolymer composed of the structural units (a0) and (a1) and a copolymer composed of the structural units (a0), (a1) and (a2). Polymer, copolymer composed of structural units (a0), (a1) and (a3), copolymer composed of structural units (a0), (a1), (a2) and (a3), structural unit (a0) , (A1), (a2), and a copolymer composed of (a4), a copolymer composed of the structural units (a0), (a1), (a2), (a3), and (a4).

The mass average molecular weight (Mw) of the component (A) (polystyrene conversion standard by gel permeation chromatography (GPC)) is not particularly limited, preferably 1000 to 50000, more preferably 1500 to 30000, 2000 to 2000 20000 is most preferred. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
The dispersity (Mw / Mn) is not particularly limited, but is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5. In addition, Mn shows a number average molecular weight.

The component (A) can be obtained by polymerizing a monomer for deriving each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).
In addition, the component (A) is used in combination with a chain transfer agent such as, for example, HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH at the time of the polymerization. A —C (CF ₃ ) ₂ —OH group may be introduced into the. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing
As the monomer for deriving each structural unit, a commercially available monomer may be used, or a monomer synthesized by a known method may be used.

As the component (A), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.

<Acid generator component (B)>
The resist composition of the present invention is an acid generator component (B) that does not fall under the component (A) and generates an acid upon exposure (hereinafter referred to as the component (B)), as long as the effects of the present invention are not impaired. .) May be contained.
The component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists can be used. Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly (bissulfonyl) diazomethanes, and the like. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.
As the onium salt acid generator, for example, a compound represented by the following general formula (b-1) or (b-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”は、それぞれ独立に、置換基を有していてもよいアリール基、アルキル基またはアルケニル基を表す。Ｒ^１”〜Ｒ^３”のうち、いずれか２つが相互に結合して式中のイオウ原子と共に環を形成してもよい。但し、式中の基Ｒ^１”−Ｓ^＋（Ｒ^２”）（Ｒ^３”）は全体で芳香環を１個のみ有するか又は芳香環を有さない、Ｒ^５”〜Ｒ^６”はこれらの全体で芳香環を１個のみ有するか又は芳香環を有しない。Ｒ^４”は、置換基を有していてもよいアルキル基、ハロゲン化アルキル基、アリール基、またはアルケニル基を表す。］

[Wherein, R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent. Any two of R ¹ ″ to R ³ ″ may be bonded to each other to form a ring together with the sulfur atom in the formula. However, the groups R ¹ ″ -S ⁺ (R ² ″) (R ³ ″) in the formula have only one aromatic ring or no aromatic ring in total, R ⁵ ″ to R ⁶ ″ are these In general, it has only one aromatic ring or no aromatic ring. R ⁴ ″ represents an alkyl group, a halogenated alkyl group, an aryl group, or an alkenyl group which may have a substituent. ]

R ¹ ″ to R ³ ″ in the formula (b-1) and R ⁵ ″ to R ⁶ ″ in the formula (b-2) are respectively the formulas (m− It is the same as R ¹ ″ to R ³ ″ in ¹ ) and R ⁵ ″ to R ⁶ ″ in formula (m-2).
Formula (b-1) ~ (b -2) in ^R 4 "SO ₃ ^- is, V in the general formula listed in the structural unit ^{(a0) (a0-1) - R} 4 mentioned in the description" SO ₃ ^- is the same as that.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation with radiation. is there. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

［式（Ｂ−１）中、Ｒ^３１、Ｒ^３２はそれぞれ独立に有機基を表す。］

[In formula (B-1), R ³¹ and R ³² each independently represents an organic group. ]

The organic groups of R ³¹ and R ³² are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), etc.) You may have.
As the organic group for R ^31, a linear, branched, or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms.
As the organic group for R ^32, a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.
R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

［式（Ｂ−２）中、Ｒ^３３は、シアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３４はアリール基である。Ｒ^３５は置換基を有さないアルキル基またはハロゲン化アルキル基である。］

[In Formula (B-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

［式（Ｂ−３）中、Ｒ^３６はシアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３７は２または３価の芳香族炭化水素基である。Ｒ^３８は置換基を有さないアルキル基またはハロゲン化アルキル基である。ｐ”は２または３である。］

[In Formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. ^R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]

In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and carbon atoms. Numbers 1 to 6 are most preferable.
R ³³ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³³ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred.
As the aryl group of R ³⁴ , one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group. And a heteroaryl group in which a part of carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Among these, a fluorenyl group is preferable.
The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.
The alkyl group or halogenated alkyl group having no substituent of R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.
R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³⁵ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred is the strength of the acid generated. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent for R ³⁶ is the same as the alkyl group or halogenated alkyl group having no substituent for R ^33. Is mentioned.
Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .
Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include the same alkyl groups or halogenated alkyl groups as those having no substituent of R ³⁵ .
p ″ is preferably 2.

Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope Nthenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.
Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [chemical formula 18] to [chemical formula 19]), pamphlet of International Publication No. 04/074242, An oxime sulfonate-based acid generator disclosed in Examples 1 to 40) on pages 65 to 86 can also be suitably used.
Moreover, the following can be illustrated as a suitable thing.

Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Examples include bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.
Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.
Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

As the component (B), one type of acid generator described above may be used alone, or two or more types may be used in combination.
0-60 mass parts is preferable with respect to 100 mass parts of (A) component, as for content of (B) component in the resist composition of this invention, 0-40 mass parts is more preferable, and 0-10 mass parts is further. preferable. When it is 40 parts by mass or less, a uniform solution is obtained when each component of the resist composition is dissolved in an organic solvent, and the storage stability is improved, which is preferable. In particular, when the content is 10 parts by mass or less, it is possible to balance the suppression of the deterioration of the lithography characteristics with respect to the OoB light and the enhancement of sensitivity.

<Other optional components>
The resist composition of the present invention may contain a basic compound (D) (hereinafter referred to as “component (D)”) as an optional component. In the present invention, the component (D) acts as an acid diffusion control agent, that is, a quencher that traps the acid generated from the component (A), the component (B), etc. by exposure. In the present invention, the “basic compound” refers to a compound that is relatively basic with respect to the component (A) or the component (B).
The component (D) in the present invention may be a basic compound (D1) (hereinafter referred to as “component (D1)”) composed of a cation moiety and an anion moiety, and does not correspond to the component (D1). It may be a basic compound (D2) (hereinafter referred to as “component (D2)”).

[(D1) component]
As the component (D1), a compound (d1-1) represented by the following general formula (d1-1) (hereinafter referred to as “(d1-1) component”), and the following general formula (d1-2): Compound (d1-2) (hereinafter referred to as “component (d1-2)”) and compound (d1-3) represented by the following general formula (d1-3) (hereinafter referred to as “(d1- 3) It is preferably at least one selected from the group consisting of “component”.

［式中、Ｒ^４は置換基を有していてもよい炭化水素基であり、Ｚ^２ｃは置換基を有していてもよい炭素数１〜３０の炭化水素基（ただし、Ｓに隣接する炭素にはフッ素原子は置換されていないものとする）であり、Ｒ^５は有機基であり、Ｙ^５は直鎖状、分岐鎖状若しくは環状のアルキレン基またはアリーレン基であり、Ｒｆ^３はフッ素原子を含む炭化水素基であり、Ｍ^＋はそれぞれ独立にスルホニウム又はヨードニウムカチオンである。］

[Wherein, R ⁴ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (however, adjacent to S R ⁵ is an organic group, Y ⁵ is a linear, branched or cyclic alkylene group or an arylene group, and Rf ³ is fluorine. It is a hydrocarbon group containing an atom, and each M ⁺ is independently a sulfonium or iodonium cation. ]

[(D1-1) component]
· During anion formula (d1-1), R ⁴ represents a hydrocarbon group which may have a substituent.
The hydrocarbon group which may have a substituent of R ⁴ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. In the description of the structural unit (a0), the general formula “ R ^{4 -} mentioned formula as a substituent which may be have "SO ₃ ^{R 4} in"^": X 3 -Q ^'- are the same as those for ^{X 3} medium.
Among them, the hydrocarbon group which may have a substituent of R ⁴ is an aromatic hydrocarbon group which may have a substituent, or an aliphatic cyclic group which may have a substituent. A phenyl group or naphthyl group which may have a substituent; one or more hydrogen atoms are removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane. More preferably, it is a group.

In addition, the hydrocarbon group which may have a substituent for R ⁴ is preferably a linear or branched alkyl group or a fluorinated alkyl group.
The number of carbon atoms of the linear or branched alkyl group of R ⁴ is preferably 1 to 10, specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, Linear alkyl group such as heptyl group, octyl group, nonyl group, decyl group, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3- Examples thereof include branched alkyl groups such as methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

The fluorinated alkyl group for R ⁴ may be linear or cyclic, but is preferably linear or branched.
1-11 are preferable, as for carbon number of a fluorinated alkyl group, 1-8 are more preferable, and 1-4 are more preferable. Specifically, for example, a part or all of a linear alkyl group such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, etc. Or a branched chain such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, or a 3-methylbutyl group. And a group in which some or all of the hydrogen atoms constituting the alkyl group are substituted with fluorine atoms.
Moreover, the fluorinated alkyl group for R ⁴ may contain an atom other than a fluorine atom. Examples of atoms other than fluorine atoms include oxygen atoms, carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, and nitrogen atoms.
Among them, the fluorinated alkyl group for R ⁴ is preferably a group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms. It is preferable that all the hydrogen atoms which comprise are the group (perfluoroalkyl group) substituted by the fluorine atom.

  Preferred specific examples of the anion moiety of the component (d1-1) are shown below.

-Cation part In Formula (d1-1), M ^<+> is an organic cation.
Although it does not specifically limit as an organic cation of M ^<+> , For example, the thing similar to the cation part of the compound represented by the said Formula (b-1) or (b-2) is mentioned.
As the component (d1-1), one type may be used alone, or two or more types may be used in combination.

[(D1-2) component]
Anion formula ^{(d1-2), Z 2c} is a hydrocarbon group of 1 to 30 carbon atoms which may have a substituent.
The hydrocarbon group having 1 to 30 carbon atoms which may have a substituent of Z ^2c may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and the above formula (d1-1) those in the same manner as R ⁴ of the like.
Among them, the hydrocarbon group which may have a substituent of Z ^2c is preferably an aliphatic cyclic group which may have a substituent, adamantane, norbornane, isobornane, tricyclodecane, It is more preferably a group obtained by removing one or more hydrogen atoms from tetracyclododecane, camphor or the like (which may have a substituent).
The hydrocarbon group for Z ^2c may have a substituent, and examples of the substituent include the same as those for X in the component (B). However, in Z ^2c , the carbon adjacent to the S atom in SO ₃ ^— is not fluorine-substituted. Since SO ₃ ^— and a fluorine atom are not adjacent to each other, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability of the component (D) is improved.
Preferred specific examples of the anion moiety of the component (d1-2) are shown below.

During cation portion formula (d1-2), ^{M +} is the same as ^{M +} in the formula (d1-1) in.
As the component (d1-2), one type may be used alone, or two or more types may be used in combination.

[(D1-3) component]
Anion formula (d1-3), ^{R 5} is an organic group.
The organic group for R ⁵ is not particularly limited, but is an alkyl group, an alkoxy group, —O—C (═O) —C (R ^C2 ) ═CH ₂ (R ^C2 is a hydrogen atom, a carbon number of 1 to 5). Or an alkyl group having 1 to 5 carbon atoms), or —O—C (═O) —R ^C3 (R ^C3 is a hydrocarbon group).
The alkyl group of R ⁵ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group. Tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of hydrogen atoms of the alkyl group of R ² may be substituted with a hydroxyl group, a cyano group, or the like.
The alkoxy group of R ⁵ is preferably an alkoxy group having 1 to 5 carbon atoms. Specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Examples include butoxy group and tert-butoxy group. Of these, a methoxy group and an ethoxy group are most preferable.

When R ⁵ is —O—C (═O) —C (R ^C2 ) ═CH ₂ , R ^C2 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. is there.
The alkyl group having 1 to 5 carbon atoms in R ^C2 is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, n -Butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like can be mentioned.
The halogenated alkyl group in R ^C2 is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
R ^C2 is preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a fluorinated alkyl group having 1 to 3 carbon atoms, and is most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.

When R ⁵ is —O—C (═O) —R ^C3 , R ^C3 is a hydrocarbon group.
The hydrocarbon group for R ^C3 may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Specific examples of the hydrocarbon group for R ^C3 include the same groups as those described above for R ⁴ in formula (d1-1).
Among them, as the hydrocarbon group of R ^C3 , an alicyclic group in which one or more hydrogen atoms are removed from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like, Aromatic groups such as phenyl group and naphthyl group are preferred. When R ^C3 is an alicyclic group, the resist composition is well dissolved in an organic solvent, so that the lithography properties are improved. Further, when R ^C3 is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition is excellent in light absorption efficiency, and sensitivity and lithography characteristics are good.

Among them, as R ⁵ , —O—C (═O) —C (R ^C2 ′) ═CH ₂ (R ^C2 ′ is a hydrogen atom or a methyl group), or —O—C (═O ) -R ^C3 ′ (R ^C3 ′ is an aliphatic cyclic group).

In formula (d1-3), Y ⁵ represents a linear, branched or cyclic alkylene group or an arylene group.
As the linear, branched or cyclic alkylene group or arylene group for Y ⁵ , among the divalent linking groups for Y ^{22 in} the above formula (a1-0-2), “linear or branched chain” And the same as the “cyclic aliphatic hydrocarbon group”, “cyclic aliphatic hydrocarbon group”, and “aromatic hydrocarbon group”.
Among these, Y ⁵ is preferably an alkylene group, more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.

In formula (d1-3), Rf ³ represents a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom of Rf ³ is preferably a fluorinated alkyl group, and more preferably the same as the fluorinated alkyl group of R ⁴ above.
Preferred specific examples of the anion moiety of the component (d1-3) are shown below.

During cation portion formula (d1-3), ^{M +} is the same as ^{M +} in the formula (d1-1) in.
As the component (d1-3), one type may be used alone, or two or more types may be used in combination.

The component (D1) may contain only one of the above components (d1-1) to (d1-3), or may contain two or more. Especially, it is especially preferable to contain (d1-2) component.
The content of the component (D1) is preferably 0.5 to 10.0 parts by mass and more preferably 0.5 to 8.0 parts by mass with respect to 100 parts by mass of the component (A). 1.0 to 8.0 parts by mass is more preferable, and 2.5 to 5.5 parts by mass is particularly preferable. When it is at least the lower limit of the above range, particularly good lithography properties and resist pattern shape can be obtained. When the amount is not more than the upper limit of the above range, the sensitivity can be maintained satisfactorily and the throughput is excellent.

(Method for producing components (d1-1) to (d1-3))
The manufacturing method of (d1-1) component and (d1-2) component is not specifically limited, It can manufacture by a well-known method.
The production method of the component (d1-3) is not particularly limited. For example, when R ⁵ in the formula (d1-3) is a group having an oxygen atom at the terminal bonded to Y ⁵ , By reacting the compound (i-1) represented by the following general formula (i-1) with the compound (i-2) represented by the following general formula (i-2), the following general formula (i-2) -3) is obtained, and the compound (i-3) is reacted with Z ⁻ M ⁺ (i-4) having a desired cation M ⁺ to give a general formula ( The compound (d1-3) represented by d1-3) is produced.

［式中、Ｒ^５、Ｙ^５、Ｒｆ^３、Ｍ^＋は、それぞれ、前記一般式（ｄ１−３）中のＲ^５、Ｙ^５、Ｒｆ^３、Ｍ^＋と同じである。Ｒ^５ａはＲ^５から末端の酸素原子を除いた基であり、Ｚ⁻は対アニオンである。］

^{Wherein, R 5, Y 5, Rf} 3, M + , respectively, the general formula (d1-3) ^R 5 ^in, Y ^5, Rf 3, is the same as ^{M +.} R ^5a is a group obtained by removing a terminal oxygen atom from R ⁵ , and Z ⁻ is a counter anion. ]

First, compound (i-1) and compound (i-2) are reacted to obtain compound (i-3).
In formula (i-1), R ^5a is a group obtained by removing a terminal oxygen atom from R ⁵ . In formula (i-2), Y ⁵ and Rf ³ are the same as described above.
As compound (i-1) and compound (i-2), commercially available compounds may be used or synthesized.
The method for obtaining compound (i-3) by reacting compound (i-1) with compound (i-2) is not particularly limited. For example, compound (i-) can be obtained in the presence of an appropriate acid catalyst. After reacting 2) and compound (i-1) in an organic solvent, the reaction mixture can be washed and recovered.

The acid catalyst in the said reaction is not specifically limited, For example, toluenesulfonic acid etc. are mentioned, The usage-amount is about 0.05-5 mol with respect to 1 mol of compounds (i-2).
The organic solvent in the above reaction is not particularly limited as long as it can dissolve the compound (i-1) and the compound (i-2), which are raw materials, and specific examples thereof include toluene. It is preferable that it is 0.5-100 mass parts with respect to (i-1), and it is more preferable that it is 0.5-20 mass parts. A solvent may be used individually by 1 type and may use 2 or more types together.
The amount of compound (i-2) used in the above reaction is usually preferably about 0.5 to 5 mol, more preferably about 0.8 to 4 mol, per 1 mol of compound (i-1).

The reaction time in the above reaction varies depending on the reactivity between the compound (i-1) and the compound (i-2), the reaction temperature, etc., but is usually preferably 1 to 80 hours, more preferably 3 to 60 hours. .
The reaction temperature in the above reaction is preferably 20 ° C to 200 ° C, more preferably about 20 ° C to 150 ° C.

Next, the obtained compound (i-3) and the compound (i-4) are reacted to obtain the compound (d1-3).
In formula (i-4), M ⁺ is the same as described above, and Z ⁻ is a counter anion.
The method of reacting compound (i-3) with compound (i-4) to obtain compound (d1-3) is not particularly limited, but for example, in the presence of a suitable alkali metal hydroxide It can be carried out by dissolving (i-3) in a suitable organic solvent and water, adding compound (i-4) and reacting with stirring.

The alkali metal hydroxide in the above reaction is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide and the like, and the amount used is 0.3 to 1 mol per 1 mol of compound (i-3). About 3 mol is preferable.
Examples of the organic solvent in the above reaction include solvents such as dichloromethane, chloroform, and ethyl acetate, and the amount used is preferably 0.5 to 100 parts by mass with respect to compound (i-3). More preferably, it is 5-20 mass parts. A solvent may be used individually by 1 type and may use 2 or more types together.
The amount of compound (i-4) used in the above reaction is usually preferably about 0.5 to 5 mol, more preferably about 0.8 to 4 mol, relative to 1 mol of compound (i-3).

The reaction time in the above reaction varies depending on the reactivity between the compound (i-3) and the compound (i-4), the reaction temperature, etc., but is usually preferably 1 to 80 hours, more preferably 3 to 60 hours. .
The reaction temperature in the above reaction is preferably 20 ° C to 200 ° C, more preferably about 20 ° C to 150 ° C.
After completion of the reaction, the compound (d1-3) in the reaction solution may be isolated and purified. For isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography, etc. can be used alone or in combination of two or more thereof. it can.

The structure of the compound (d1-3) obtained as described above is as follows: ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method. It can be confirmed by a general organic analysis method such as mass spectrometry (MS) method, elemental analysis method, X-ray crystal diffraction method.

[(D2) component]
The component (D2) is a compound that is relatively basic with respect to the component (A) or the component (B), and is an acid diffusion controller, that is, from the component (A) or the component (B) by exposure. It is not particularly limited as long as it acts as a quencher for trapping the generated acid and does not correspond to the component (D1), and any known one may be used. Examples thereof include amines such as aliphatic amines and aromatic amines, among which aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are preferred.
An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include amines (alkylamines or alkylalcoholamines) in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 20 or less carbon atoms, cyclic amines, other amines An aliphatic amine etc. are mentioned.

The alkyl group of the alkylamine may be linear, branched or cyclic.
When the alkyl group is linear or branched, the carbon number thereof is more preferably 2-20, and further preferably 2-8.
When the alkyl group is cyclic (when it is a cycloalkyl group), the carbon number is preferably 3 to 30, more preferably 3 to 20, still more preferably 3 to 15, and 4 to 12 carbon atoms. It is particularly preferred that the number of carbon atoms is 5-10. The alkyl group may be monocyclic or polycyclic. Specific examples include groups in which one or more hydrogen atoms have been removed from monocycloalkane, groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as bicycloalkane, tricycloalkane, and tetracycloalkane. . Specific examples of the monocycloalkane include cyclopentane and cyclohexane. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Examples of the alkyl group in the hydroxyalkyl group possessed by the alkyl alcohol amine include the same alkyl groups as those possessed by the alkyl amine.

Specific examples of the alkylamine include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di-n- Dialkylamines such as heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-hexylamine, tri-n-pentylamine, tri- and trialkylamines such as n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, and tri-n-dodecylamine.
Specific examples of the alkyl alcohol amine include diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, tri-n-octanolamine, stearyl diethanolamine, lauryldiethanolamine and the like.
Among these, a trialkylamine having 5 to 10 carbon atoms is more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.

  Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, tris {2 -(1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxy Ethoxy) ethoxy} ethylamine, triethanolamine triacetate and the like.

  Aromatic amines include aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxy. And carbonylpyrrolidine.

As the component (D2), any one type may be used alone, or two or more types may be used in combination.
(D2) A component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component. By setting the content in the above range, the resist pattern shape, the stability over time, and the like are improved.

(D) A component may be used individually by 1 type and may be used in combination of 2 or more type.
When the resist composition of this invention contains (D) component, it is preferable that content of (D) component is 0.1-15 mass parts with respect to 100 mass parts of (A) component, 0 More preferably, it is 3-12 mass parts, and it is still more preferable that it is 0.5-12 mass parts. When it is at least the lower limit of the above range, lithography properties such as roughness are further improved. Further, a better resist pattern shape can be obtained. When the amount is not more than the upper limit of the above range, the sensitivity can be maintained satisfactorily and the throughput is excellent.

The resist composition of the present invention comprises, as optional components, an organic carboxylic acid, a phosphorus oxo acid, and derivatives thereof for the purpose of preventing sensitivity deterioration and improving the resist pattern shape, retention stability over time, and the like. At least one compound (E) selected from the group (hereinafter referred to as component (E)) can be contained.
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids include phosphoric acid, phosphonic acid, and phosphinic acid. Among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of the phosphinic acid derivatives include phosphinic acid esters such as phenylphosphinic acid.
(E) A component may be used individually by 1 type and may use 2 or more types together.
(E) A component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

  If desired, the resist composition of the present invention may further contain miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving coatability, a dissolution inhibitor, a plasticizer. An agent, a stabilizer, a colorant, an antihalation agent, a dye, and the like can be appropriately added and contained.

The resist composition of the present invention can be produced by dissolving the material in an organic solvent (hereinafter sometimes referred to as (S) component).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone;
Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone;
Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol;
Compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl ether, monopropyl of the polyhydric alcohols or the compound having an ester bond Derivatives of polyhydric alcohols such as ethers, monoalkyl ethers such as monobutyl ether or compounds having an ether bond such as monophenyl ether [in these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) Is preferred];
Cyclic ethers such as dioxane and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate;
Aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. be able to.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range. For example, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3. Further, when PGME and cyclohexanone are blended as polar solvents, the mass ratio of PGMEA: (PGME + cyclohexanone) is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, and even more preferably 3. : 7 to 7: 3.
In addition, as the component (S), PGMEA, EL or a mixed solvent of PGMEA and a polar solvent and a mixed solvent of γ-butyrolactone are also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of component (S) used is not particularly limited, but is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. -20% by mass, preferably 2-15% by mass.

The resist composition of the present invention is excellent in lithography properties such as resolution and exposure margin when forming a resist pattern by EUV exposure or EB exposure, and has low roughness and rectangular cross-sectional shape. A resist pattern having a high shape (high verticality of the pattern side wall) and a good shape can be formed. The reason why such an effect is obtained is presumed as follows.
In the resist composition of the present invention, the component (A1) containing the structural unit (a0) that generates an acid upon exposure contains a uniform distribution in the exposed area from the structural unit (a0) uniformly distributed in the resist film. Acid is generated. As a result, the acid-decomposable group in the (A1) component of the exposed portion is easily decomposed uniformly, so that the lithography properties such as resolution are improved as compared with a resist composition using a conventional acid generator. I think that.
Further, the structural unit (a0) does not have an aromatic ring in the cation part, or has only one aromatic ring in the entire cation part, so that the cation has a light having a wavelength in the DUV region, particularly a wavelength of 150 to 300 nm. Since the sensitivity to light can be reduced, the light in the DUV region included in the OoB light generated from the EUV light source enters the unexposed area, or diffuses (scatters) on the surface of the electron resist film during EB exposure. It is considered that adverse effects (such as a decrease in optical contrast, generation of an acid in an unexposed area, and a change in developer solubility associated therewith) are suppressed, and the above effect can be obtained. In addition, even when there is no aromatic ring in the cation part or only one aromatic ring in the entire cation part, light with a wavelength in the EUV region (light with a wavelength around 13.5 nm) or EB Since sensitivity does not deteriorate, sufficient sensitivity can be obtained in the exposed portion.

In addition, by containing the component (C), the resist composition of the present invention can suppress the occurrence of development defects (defects) particularly after alkali development.
Here, “defect” means, for example, general defects detected when a developed resist pattern is observed from directly above by a surface defect observation apparatus (trade name “KLA”) manufactured by KLA Tencor. For example, it relates to defects such as scum (resist residue), bubbles, dust, etc. due to adhesion of foreign matter or deposits on the resist pattern surface, bridges between line patterns, and pattern shapes such as hole filling of contact hole patterns. It refers to defects and uneven color of patterns.
One cause of defects is the high hydrophobicity of the resist material. When the resist film is highly hydrophobic, deposits are likely to re-adhere to the resist surface particularly in the resist unexposed area when alkali development or subsequent water rinsing is performed. In the resist composition in which the base material component has an acid generating ability as in the present invention, and a component such as a conventional low molecular weight acid generator is an optional component, most of the components constituting the resist film are the base material. Since it becomes a component, there is a tendency that the hydrophobicity of the resist film tends to be high, and in order to make the pattern finer and improve the lithography properties, it is important to suppress the occurrence of defects. In contrast to this problem, the resist composition of the present invention contains (C) component as an essential component, which exhibits hydrophobicity on the resist surface at the time of exposure before development, and becomes hydrophilic by changing polarity after development with alkali. By doing so, it becomes possible to make the resist film hydrophilic during development. In addition, since the component (C) contains a fluorine atom or a silicon atom, it is likely to be unevenly distributed near the surface of the resist film. Therefore, the surface of the resist film obtained using the resist composition containing the component (C) changes to hydrophilic after alkali development particularly well. Thus, the surface of the resist film becomes hydrophilic after alkali development, so that defects after development, particularly defects (Blob) related to scum and dust reattachment to the film surface are reduced.

≪Resist pattern formation method≫
The resist pattern forming method of the present invention includes a step of forming a resist film on a support using the resist composition of the first aspect, a step of exposing the resist film by EUV or EB, and the resist film And developing to form a resist pattern.
The resist pattern forming method of the present invention can be performed, for example, as follows.
First, the resist composition of the first aspect of the present invention is applied onto a support with a spinner or the like, and a baking (post-apply bake (PAB)) treatment is performed at a temperature of 80 to 150 ° C. for 40 to 120 seconds, for example. The resist film is formed preferably for 60 to 90 seconds.
Next, the resist film is exposed through a mask (mask pattern) on which a predetermined pattern is formed using an exposure apparatus such as an EB drawing apparatus or an EUV exposure apparatus, or an electron beam not through the mask pattern. After performing selective exposure such as drawing by direct irradiation, baking (post-exposure baking (PEB)) treatment is performed, for example, at a temperature of 80 to 150 ° C. for 40 to 120 seconds, preferably 60 to 90 seconds.
Next, the resist film is developed. In the case of an alkali development process, an alkali development treatment is performed using an alkali developer, for example, a 0.1 to 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution. In the case of a solvent development process, development processing is performed using an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specific examples include ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and other polar solvents, hydrocarbon solvents, and the like, with ester solvents being preferred. As the ester solvent, butyl acetate is preferred.
A rinsing treatment is preferably performed after the development treatment. In the case of an alkali development process, water rinsing using pure water is preferable. In the case of the solvent development process, it is preferable to use a rinse solution containing the organic solvent mentioned above.
Thereafter, drying is performed. In some cases, a baking process (post-bake) may be performed after the development process.
In this way, a resist pattern can be obtained. The resist composition of the present invention is particularly suitably used for a method of forming a positive resist pattern by an alkali development process.

The support is not particularly limited, and a conventionally known one can be used, and examples thereof include a substrate for electronic components and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon substrate, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
Further, the support may be a substrate in which an inorganic and / or organic film is provided on the above-described substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include organic films such as an organic antireflection film (organic BARC) and a lower organic film in a multilayer resist method.
Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are provided on a substrate, and the resist pattern formed on the upper resist film is used as a mask. This is a method of patterning a lower organic film, and it is said that a pattern with a high aspect ratio can be formed. That is, according to the multilayer resist method, the required thickness can be secured by the lower organic film, so that the resist film can be thinned and a fine pattern with a high aspect ratio can be formed.
In the multilayer resist method, basically, a method of forming a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers between the upper resist film and the lower organic film And a method of forming a multilayer structure of three or more layers (metal thin film etc.) (three-layer resist method).

The exposure method of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be immersion exposure (Liquid Immersion Lithography).
In immersion exposure, the space between the resist film and the lens at the lowest position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than that of air, and exposure (immersion exposure) is performed in that state. It is an exposure method.
As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film to be exposed is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.
Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent.
Specific examples of the fluorine-based inert liquid include a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as a main component. Examples thereof include liquids, and those having a boiling point of 70 to 180 ° C are preferable, and those having a boiling point of 80 to 160 ° C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point in the above range since the medium used for immersion can be removed by a simple method after the exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.
More specifically, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C.). Examples of the perfluoroalkylamine compound include perfluorotributylamine ( Boiling point of 174 ° C.).
As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility, and the like.

Examples of the alkali developer used for the development treatment in the alkali development process include a 0.1 to 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.
The organic solvent contained in the organic developer used for the development process in the solvent development process is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure). It can be selected as appropriate. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents can be used.
A known additive can be blended in the organic developer as required. Examples of the additive include a surfactant. The surfactant is not particularly limited. For example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used.
When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0. 0% with respect to the total amount of the organic developer. 5 mass% is more preferable.
The development process can be carried out by a known development method, for example, a method in which a support is immersed in a developer for a certain period of time (dip method), a developer is raised on the surface of the support by surface tension, and is left for a certain period of time. (Paddle method), spraying developer on the surface of the support (spray method), coating the developer while scanning the developer coating nozzle at a constant speed on the support rotating at a constant speed The method to continue (dynamic dispensing method) etc. are mentioned.

As the organic solvent contained in the rinsing liquid used for the rinsing treatment after the development process in the solvent development process, for example, among the organic solvents mentioned as the organic solvent contained in the organic developer, those that are difficult to dissolve the resist pattern are appropriately used. You can select and use. Usually, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is used. Among these, at least one selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents and amide solvents is preferable, and at least one selected from alcohol solvents and ester solvents is preferable. More preferred are alcohol solvents.
The rinsing treatment (washing treatment) using the rinsing liquid can be carried out by a known rinsing method. For example, the rinsing liquid is continuously applied onto a support rotating at a constant speed (rotary coating method). A method of immersing the support in a rinsing solution for a certain time (dip method), a method of spraying a rinsing solution on the surface of the support (spray method), and the like.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.

[Polymer Synthesis Examples 1-20: Synthesis of Polymer Compounds 1-20]
The high molecular compounds 1-20 were synthesize | combined by the conventional method using the following monomers (1)-(29) which derive | lead the structural unit which comprises each high molecular compound. The polymer compounds having monomers (4) to (6), (8) to (14), (19) and (23) are monomers (4) to (6), (8) to (14), In (19) and (23), the polymer was once polymerized using the monomer whose counter cation is triphenylsulfonium, and then salt exchanged with the target counter cation by a conventional method. An example of synthesizing the derivative of monomer (8) used for salt exchange of the target counter cation will be described later.
The obtained polymer compound, as a result of an analysis by carbon 13 nuclear magnetic resonance spectrum (600 MHz - ¹³ C-NMR) (ratio of the respective structural units within the structural formula (molar ratio)) was measured by GPC The weight average molecular weight (Mw) and molecular weight dispersity (Mw / Mn) in terms of standard polystyrene are shown in Tables 1 and 2, respectively.

[Synthesis example]
Under a nitrogen atmosphere, Compound A (4.3 g) was dissolved in acetonitrile (21.6 g), and heptahydrothiophene (2.0 g) was added dropwise thereto, followed by stirring at 25 ° C. for 12 hours. Thereafter, the precipitated white powder was collected by suction filtration, washed with acetonitrile (11.3 g), and dried under reduced pressure to obtain 2.9 g of a monomer 8 precursor.
The obtained compound was subjected to NMR measurement, and the structure was identified from the following results.
¹ H-NMR (400 MHz, DMSO-d ₆ + D ₂ O): δ (ppm) = 5.1 (t, 2H, CH), 4.6 (t, 2H, CH), 4.3 (s, 1H , CH2), 3.9 (m, 3H, CH), 3.6-3.8 (t, 2H, SCH2), 3.4 (t, 2H, CH 2), 2.9 (m, 5H, _{CH), 2.4 (4H, CH} ), 2.0 (t, 2H, CH 2), 1.7-1.9 (m, 3H, CH 2 CH 2), 1.2-1.4 ( m, 4H, CH ₂ CH ₂ CH ₂ )

[Examples 1 to 24, Comparative Examples 1 to 3]
Each component shown in Tables 3 to 4 was mixed and dissolved to prepare a resist composition. Examples 5, 6, 11 and 14 are reference examples.

In Tables 3 to 4, each abbreviation has the following meaning. The numerical value in [] is a compounding amount (part by mass). In addition, (C) component was synthesize | combined by the conventional method.
(A) -1 to (A) -20: The above polymer compounds (1) to (20).
(C) -1: a copolymer represented by the following formula (C) -1 [Mw = 14000, Mw / Mn = 1.70, 1 / m = 70/30 (molar ratio)].
(C) -2: a copolymer represented by the following formula (C) -2 [Mw = 20000, Mw / Mn = 1.93, 1 / m = 80/20 (molar ratio)].
(C) -3: a copolymer represented by the following formula (C) -3 [Mw = 24000, Mw / Mn = 1.83, 1 / m = 77/23 (molar ratio)].
(C) -4: a copolymer represented by the following formula (C) -4 [Mw = 19200, Mw / Mn = 1.83, 1 / m / n = 25/20/55 (molar ratio)].
(C) -5: a copolymer represented by the following formula (C) -5 [Mw = 15600, Mw / Mn = 1.86, 1 / m / n = 60/17/23 (molar ratio)].
(C) -6: a copolymer represented by the following formula (C) -6 [Mw = 24800, Mw / Mn = 2.30, 1 / m = 65/35 (molar ratio)].
(C) -7: a copolymer represented by the following formula (C) -7 [Mw = 17700, Mw / Mn = 1.90, 1 / m = 55/45 (molar ratio)].
(D) -1: A compound represented by the following structural formula (D) -1.
(D) -2: tri-n-octylamine.
(D) -3: A compound represented by the following structural formula (D) -3.
(D) -4: A compound represented by the following structural formula (D) -4.
(E) -1: salicylic acid.
(S) -1: γ-butyrolactone.
(S) -2: Mixed solvent of PGMEA / PGME / cyclohexanone = 15/10/25 (mass ratio).

The following evaluation was performed using the obtained resist composition.
[Formation of resist pattern]
The resist composition of each example was uniformly applied using a spinner on an 8-inch silicon substrate subjected to hexamethyldisilazane (HMDS) treatment at 90 ° C. for 36 seconds, and the PAB temperatures shown in Tables 5 to 6 were obtained. Then, a baking process (PAB) for 60 seconds was performed to form a resist film (film thickness 60 nm). The resist film is drawn (exposed) at an acceleration voltage of 50 kV using an electron beam lithography machine HL800D (VSB) (manufactured by Hitachi), and baked for 60 seconds at the PEB temperatures shown in Tables 5 to 6 (PEB). And developed for 60 seconds at 23 ° C. using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) (trade name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.). .
As a result, in each example, a line-and-space resist pattern (hereinafter referred to as “LS pattern”) having a line width of 100 nm and a pitch of 200 nm was formed.
The optimum exposure dose Eop (μC / cm ² ) at which the LS pattern is formed was determined. The results are shown in Tables 5-6.
In addition, although it is thought that it is advantageous for formation of a fine pattern, so that an acceleration voltage is high, in this evaluation, in order to reproduce the state in which OoB light has arisen, it is (relatively low) acceleration voltage 50kV Exposure conditions were adopted.

[Evaluation of resolution]
The limiting resolution (nm) in the Eop was determined using a scanning electron microscope S-9380 (manufactured by Hitachi High-Technology Corporation). The results are shown in Tables 5 to 6 as “resolution”.

[Evaluation of line edge roughness (LWR)]
With respect to the LS pattern having a line width of 100 nm and a pitch of 200 nm formed in [Formation of resist pattern], 3σ, which is a scale indicating LWR, was obtained. “3σ” is a standard obtained from a measurement result obtained by measuring 400 line widths in the longitudinal direction of a line with a scanning electron microscope (acceleration voltage 800 V, trade name: S-9220, manufactured by Hitachi High-Technologies Corporation). The triple value (3 s) (unit: nm) of the deviation (σ) is shown. The smaller the value of 3s, the smaller the roughness of the line side wall, which means that an LS pattern having a more uniform width was obtained. The results are shown in Tables 5-6.

[Evaluation of exposure margin (10% EL)]
In the above [Resist pattern formation], the exposure amount when the line of the LS pattern is formed within a range of ± 10% (90 nm to 110 nm) of the target dimension (line width 100 nm) is obtained. The degree (unit:%) was determined. The exposure margin indicates that the larger the value is, the smaller the change amount of the pattern size with the fluctuation of the exposure amount. The results are shown in Tables 5 to 6 as “10% EL”.
Exposure margin (%) = (| E1-E2 | / Eop) × 100
In the formula, E1 represents an exposure amount (μC / cm ² ) when an LS pattern having a line width of 90 nm is formed, and E2 represents an exposure amount (μC / cm ² ) when an LS pattern having a line width of 110 nm is formed. .

  As shown in the above results, the resist compositions of Examples 1 to 24 have sufficiently good sensitivity to EB, and are excellent in resolving power as compared with the resist compositions of Comparative Examples 1 to 3. It was confirmed that the lithography characteristics such as exposure margin and roughness were excellent.

Claims (3)

A base component (A) that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid;
A resist composition for EUV or EB containing at least one selected from a fluorine atom and a silicon atom, and a resin component (C) having a polarity conversion group that is decomposed by the action of a base to increase polarity. And
The base material component (A) contains a polymer compound (A1) having a structural unit (a0) having a group represented by the following general formula (a0-1) or (a0-2),
A resist composition for EUV or EB, comprising 1 to 15 parts by mass of the resin component (C) with respect to 100 parts by mass of the substrate component (A).

[Wherein, Q ¹ and Q ² are each independently a single bond or a divalent linking group. R ³ , R ⁴ and R ⁵ are each independently an organic group, and R ⁴ and R ⁵ may be bonded to each other to form a ring together with the sulfur atom in the formula. However, group -R ^{< 3 >} -S ^<+> (R ^{< 4 >} ) (R ^{< 5 >} ) in a formula does not have an aromatic ring . V ⁻ is a counter anion. A ^- is an organic group containing anion. M ^{m +} is an m-valent organic cation, and m is an integer of 1 to 3. However, M ^{m +} does not have an aromatic ring . ]   The resist composition for EUV or EB according to claim 1, wherein the polymer compound (A1) has a structural unit (a1) containing an acid-decomposable group whose polarity increases by the action of an acid.   A step of forming a resist film on the support using the resist composition for EUV or EB according to claim 1, a step of exposing the resist film with EUV or EB, and developing the resist film A resist pattern forming method including a step of forming a resist pattern.