KR20210067912A - Resist composition and method of forming resist pattern - Google Patents

Abstract

The present invention relates to a resist composition that generates an acid by exposure and changes solubility in a developer by the action of the acid. The resist composition having concentration of 25 mass% or more of solid content includes: a base component (A) whose solubility in a developer changes due to the action of the acid; and an ionic liquid (Z).

Description

RESIST COMPOSITION AND METHOD OF FORMING RESIST PATTERN

The present invention relates to a resist composition and a method for forming a resist pattern.

This application claims priority on the basis of Japanese Patent Application No. 2019-217161, filed in Japan on November 29, 2019, and Japanese Patent Application No. 2020-156373, filed on September 17, 2020 in Japan, The content is cited here.

In the lithography technique, for example, a step of forming a resist film made of a resist material on a substrate, selectively exposing the resist film, and performing a development treatment to form a resist pattern having a predetermined shape on the resist film This is carried out A resist material in which the exposed portion of the resist film changes in a characteristic which dissolves in a developer is called a positive type, and a resist material in which the exposed portion of the resist film changes in a characteristic in which the characteristic is insoluble in a developer is referred to as a negative type.

In recent years, in manufacture of a semiconductor element and a liquid crystal display element, pattern refinement|miniaturization is advancing rapidly with the progress of lithography technology. As a method of miniaturization, the wavelength reduction (higher energy) of an exposure light source is generally implemented. Specifically, conventionally, ultraviolet rays typified by g-rays and i-rays have been used. Currently, semiconductor devices using KrF excimer lasers and ArF excimer lasers are being mass-produced. Moreover, examination is made also about EUV (extreme ultraviolet rays), EB (electron beam), X-rays, etc. which have a shorter wavelength (high energy) than these excimer lasers.

The resist material is required to have lithographic properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with fine dimensions.

As a resist material that satisfies these requirements, conventionally, a chemically amplified resist composition containing a base component whose solubility in a developer changes due to the action of an acid and an acid generator component that generates an acid upon exposure has been used. .

For example, when the developer is an alkali developer (alkali developing process), a 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 (base resin) and an acid generator Those containing ingredients are generally used. When a resist film formed using such a resist composition is selectively exposed during resist pattern formation, an acid is generated from the acid generator component in the exposed portion, and the polarity of the base resin is increased by the action of the acid, The exposed portion of the resist film becomes soluble with respect to the alkali developer. Therefore, by alkali development, a positive pattern in which the unexposed portion of the resist film remains as a pattern is formed.

On the other hand, when such a chemically amplified resist composition is applied to a solvent development process using a developer containing an organic solvent (organic developer), the solubility in the organic developer is relatively reduced when the polarity of the base resin is increased. 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 of the resist film remains as a pattern. The solvent development process for forming a negative resist pattern in this way is sometimes referred to as a negative development process.

Until now, as a base resin for chemically amplified resist compositions, for example, polyhydroxystyrene (PHS) with high transparency to a KrF excimer laser (248 nm) or a resin in which the hydroxyl group is protected with an acid dissociable dissolution inhibitor. (PHS-based resin) has been used. Also, for example, with respect to an ArF excimer laser (193 nm), a resin ((meth)acrylic resin) in which a hydroxyl group in the carboxy group of (meth)acrylic acid is protected with an acid dissociable dissolution inhibiting group has been used (for example, , see Patent Document 1).

Examples of the acid dissociable dissolution inhibiting group include a so-called acetal group such as a chain ether group represented by a 1-ethoxyethyl group or a cyclic ether group represented by a tetrahydropyranyl group, and a tertiary alkyl group represented by a tert-butyl group. , a tertiary alkoxycarbonyl group represented by a tert-butoxycarbonyl group, etc. are mainly used.

In addition, various types of acid generator components used in chemically amplified resist compositions have been proposed so far, for example, onium salt-based acid generators such as iodonium salts and sulfonium salts, and oxime sulfonate-based acids. Generators, diazomethane-based acid generators, nitrobenzylsulfonate-based acid generators, iminosulfonate-based acid generators, disulfone-based acid generators, and the like are known.

Among these, onium salt-based acid generators are widely used, and those having an onium ion such as triphenylsulfonium in the cation moiety are mainly used. For the anion moiety of the onium salt-based acid generator, generally, an alkylsulfonic acid ion or a fluorinated alkylsulfonate ion in which some or all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms are used.

However, at present, along with high integration of LSI and high speed of communication, an increase in memory capacity is required, and further miniaturization of patterns is rapidly progressing. However, although electron beam or EUV lithography aims to form a fine pattern of several tens of nm, there are still many problems such as low productivity, and there is a limit to the technique by micromachining.

On the other hand, in addition to miniaturization, development of a three-dimensional structure device is progressing in which the memory capacity can be increased by stacking cells by stacking them.

Japanese Patent Laid-Open No. 2003-241385

In the production of the above three-dimensional structure device, a process of forming a thick resist film having a higher film thickness, for example, a film thickness of 5 µm or more, on the surface of the object to be processed, forming a resist pattern, and performing etching, etc. has When a chemically amplified resist composition is used here, as the film thickness of the resist film becomes thicker, it is difficult to maintain the sensitivity during exposure, the resolution for development decreases, and it is difficult to obtain a desired resist pattern shape. have. Moreover, there also exists a problem that cracks are easy to generate|occur|produce in a resist pattern, so that the film thickness of a resist film becomes thick.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist composition capable of forming a thick resist film, which is less prone to cracking and has good sensitivity, and a method for forming a resist pattern using the resist composition.

In order to solve the said subject, this invention employ|adopted the following structures.

That is, the first aspect of the present invention is a resist composition that generates an acid upon exposure and changes solubility in a developer by the action of an acid, and a base component whose solubility in a developer changes by the action of an acid. A resist composition containing (A) and an ionic liquid (Z) having a solid content concentration of 25 mass% or more.

A second aspect of the present invention provides a step of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film, and developing the resist film after exposure to form a resist pattern. It is characterized in that it has, a resist pattern formation method.

According to the present invention, it is possible to provide a resist composition capable of forming a thick resist film, which is less prone to cracking and has good sensitivity, and a method for forming a resist pattern using the resist composition.

In the present specification and claims, "aliphatic" is a concept relative to aromatic, and is defined as meaning a group, compound, etc. that do not have aromaticity.

Unless otherwise specified, "alkyl group" includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The alkyl group in the alkoxy group is the same.

The "alkylene group" includes divalent saturated hydrocarbon groups of linear, branched and cyclic unless otherwise specified.

The "halogenated alkyl group" is a group in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

A "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which part or all of the hydrogen atoms of an alkyl group or an alkylene group are substituted with fluorine atoms.

A "structural unit" means a monomer unit (monomer unit) constituting a high molecular compound (resin, polymer, copolymer).

When describing "may have a substituent" or "may have a substituent", a case where a hydrogen atom (-H) is substituted with a monovalent group, and a case where a methylene group (-CH ₂ -) is substituted with a divalent group includes both sides of

"Exposure" is a concept including radiation irradiation in general.

The "base component" is an organic compound having film-forming ability, and preferably an organic compound having a molecular weight of 500 or more is used. When the molecular weight of the organic compound is 500 or more, the film-forming ability is improved and, further, it becomes easy to form a nano-level resist pattern. Organic compounds used as the base component are roughly classified into non-polymers and polymers. As a non-polymer, the thing of molecular weight 500 or more and less than 4000 is used normally. Hereinafter, when referred to as a "low molecular weight compound", molecular weights are 500 or more and less than 4000 nonpolymers. As a polymer, a thing with a molecular weight of 1000 or more is used normally. Hereinafter, when referred to as "resin", "polymer compound", or "polymer", a polymer having a molecular weight of 1000 or more is indicated. As molecular weight of a polymer, the weight average molecular weight of polystyrene conversion by GPC (gel permeation chromatography) shall be used.

"Structural unit derived from acrylic acid ester" means a structural unit constituted by cleavage of the ethylenic double bond of acrylic acid ester.

"Acrylate ester" is, acrylic acid (CH ₂ = CH-COOH) is a compound substituted with a hydrogen atom of the carboxyl terminus of the organic.

In the acrylic acid ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. ^{The substituent (R α0} ) for substituting a hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than a hydrogen atom, and examples thereof include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms. have. Further, the substituent (R ^α0) is an itaconic diester substituted with a substituent containing an ester bond or a substituent (R ^α0) a hydroxy group or by including an α-hydroxy acrylic ester is substituted with the formula the hydroxyl group do. In addition, unless otherwise indicated, the carbon atom at the alpha-position of acrylic acid ester means the carbon atom to which the carbonyl group of acrylic acid couple|bonded.

Hereinafter, the acrylic acid ester in which the hydrogen atom couple|bonded with the carbon atom at the α-position was substituted with a substituent may be referred to as an α-substituted acrylic acid ester. Moreover, acrylic acid ester and alpha-substituted acrylic acid ester may be collectively called "(alpha)-substituted) acrylic acid ester."

The "structural unit derived from hydroxystyrene" means a structural unit constituted by cleavage of the ethylenic double bond of hydroxystyrene. The "structural unit derived from a hydroxystyrene derivative" means a structural unit constituted by cleavage of the ethylenic double bond of the hydroxystyrene derivative.

The "hydroxystyrene derivative" is a concept including those in which the hydrogen atom at the α-position of hydroxystyrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As those derivatives, the hydrogen atom of the hydroxyl group of the hydroxystyrene which the hydrogen atom at the (alpha)-position may be substituted with the substituent is substituted by the organic group; The thing etc. which the substituent other than a hydroxyl group couple|bonded with the benzene ring of hydroxystyrene which the hydrogen atom at the alpha-position may be substituted with the substituent is mentioned. Incidentally, the α-position (a carbon atom at the α-position) refers to a carbon atom to which the benzene ring is bonded, unless otherwise specified.

Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include the same substituents as those mentioned as the substituent at the α-position in the α-substituted acrylic acid ester.

"Structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative" means a structural unit constituted by cleavage of an ethylenic double bond of vinylbenzoic acid or a vinylbenzoic acid derivative.

The "vinyl benzoic acid derivative" is a concept including those in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As those derivatives, the hydrogen atom of the carboxy group of vinylbenzoic acid which the hydrogen atom at the alpha-position may be substituted with the substituent is substituted with the organic group; and the like in which a substituent other than a hydroxyl group and a carboxy group couple|bonded with the benzene ring of vinylbenzoic acid which the hydrogen atom at the alpha-position may be substituted with the substituent. Incidentally, the α-position (a carbon atom at the α-position) refers to a carbon atom to which the benzene ring is bonded, unless otherwise specified.

The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, iso butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.

Specific examples of the halogenated alkyl group as the substituent at the α-position include a group in which some or all of the hydrogen atoms in the “alkyl group as a substituent at the α-position” are substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as this halogen atom, A fluorine atom is especially preferable.

In addition, specific examples of the hydroxyalkyl group as a substituent at the α-position include a group in which a part or all of the hydrogen atoms of the “alkyl group as a substituent at the α-position” are substituted with a hydroxyl group. 1-5 are preferable and, as for the number of the hydroxyl groups in this hydroxyalkyl group, 1 is the most preferable.

In the present specification and claims, depending on the structure represented by the chemical formula, an asymmetric carbon may exist, and an enantiomer or a diastereomer may exist. In that case, those isomers are represented by a single chemical formula. These isomers may be used independently and may be used as a mixture.

(resist composition)

The resist composition according to the first aspect of the present invention generates an acid upon exposure, and its solubility in a developer is changed by the action of an acid, and is a base component whose solubility in a developer is changed by the action of the acid. (A) (hereinafter also referred to as “component (A)”) and ionic liquid (Z) (hereinafter also referred to as “component (Z)”) are contained. The solid content concentration of the resist composition of the present embodiment is 25 mass% or more.

When a resist film is formed using such a resist composition, a thick resist film (for example, a film thickness of 5 mu m or more) can be formed.

When a resist film is formed using such a resist composition and the resist film is selectively exposed, acid is generated in the exposed portion of the resist film, and the solubility of component (A) in the developer is changed by the action of the acid. On the other hand, since the solubility of component (A) in the developer does not change in the unexposed portion of the resist film, a difference in solubility in the developer occurs between the exposed portion and the unexposed portion of the resist film. Therefore, when the resist film is developed, when the resist composition is of a positive type, the exposed portion of the resist film is dissolved and removed to form a positive resist pattern. When the resist composition is of the negative type, the unexposed portion of the resist film is dissolved and removed and the negative portion is removed. type resist pattern is formed.

In this specification, the resist composition in which the resist film exposed portion is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and the resist composition in which the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern is referred to as a negative resist composition. It is called composition. The resist composition of the present embodiment may be a positive resist composition or a negative resist composition. In addition, the resist composition of this embodiment may be for an alkali developing process using an alkali developing solution for the developing treatment at the time of forming a resist pattern, or a solvent developing process using a developing solution containing an organic solvent (organic developer) for the developing treatment. It may be easy.

The resist composition of the present embodiment has an acid-generating ability to generate an acid upon exposure, the component (A) may generate an acid upon exposure, and an additive component blended separately from the component (A) is subjected to exposure. acid may be generated by

Specifically, the resist composition of the present embodiment may further contain (1) an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as “component (B)”); (2) (A) The component which generate|occur|produces an acid by exposure may be sufficient; (3) (A) component is a component which generate|occur|produces an acid by exposure, and may contain (B) component further. That is, in the case of the above (2) and (3), the component (A) becomes "a base component that generates an acid upon exposure and whose solubility in a developing solution changes due to the action of the acid". When component (A) is a base component that generates an acid upon exposure and changes solubility in a developer by the action of an acid, component (A1) described later generates an acid upon exposure, and It is preferable that it is a high molecular compound whose solubility with respect to a developing solution changes by the action of an acid. As such a high molecular compound, resin which has a structural unit which generate|occur|produces an acid by exposure can be used. As a structural unit which generate|occur|produces an acid by exposure, a well-known thing can be used. Especially, it is preferable that the resist composition of this embodiment is the case of said (1).

<(A) component>

In the resist composition of the present embodiment, the component (A) preferably contains the resin component (A1) (hereinafter also referred to as “component (A1)”) whose solubility in a developer changes due to the action of an acid. By using the component (A1), since the polarity of the base component changes before and after exposure, good development contrast can be obtained not only in the alkali developing process but also in the solvent developing process.

As (A) component, at least (A1) component is used, and you may use together another high molecular compound and/or a low molecular weight compound with the (A1) component.

When an alkali developing process is applied, the base component containing the component (A1) is poorly soluble in an alkali developer before exposure. For example, when an acid is generated from component (B) by exposure, the action of the acid is affected. polarity is increased and solubility in an alkali developer is increased. Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed to light, the exposed portion of the resist film changes from poorly soluble to soluble in an alkali developer, while the resist film is not exposed. Since the miner is hardly soluble in alkali and does not change, a positive resist pattern is formed by alkali development.

On the other hand, when a solvent development process is applied, the base component containing the component (A1) has high solubility in an organic developer before exposure, and for example, when an acid is generated from component (B) by exposure, the acid The action increases the polarity and reduces the solubility in the organic developer. Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed to light, the exposed portion of the resist film changes from soluble to poorly soluble in an organic developer, while the resist film is not exposed. Since the light part remains soluble and does not change, by developing with an organic developer, contrast can be provided between the exposed part and the unexposed part, and a negative resist pattern is formed.

In the resist composition of this embodiment, the component (A) may be used individually by 1 type, and may use 2 or more types together.

・(A1) About component

(A1) Component is a resin component whose solubility with respect to a developing solution changes by the action|action of an acid. (A1) As a component, it is preferable to have a structural unit (a1) containing an acid-decomposable group whose polarity increases by the action of an acid.

(A1) In addition to the structural unit (a1), a component may have another structural unit as needed.

≪Constituting unit (a1)≫

A structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity increases by the action of an acid.

The "acid-decomposable group" is a group having acid-decomposable properties capable of cleaving at least some bonds in the structure of the acid-decomposable group by the action of an acid.

As an acid-decomposable group whose polarity increases by the action of an acid, for example, a group that generates a polar group by decomposing by the action of an acid is exemplified.

As a polar group, a carboxy group, a hydroxyl group, an amino group, a sulfo group (-SO ₃ H), etc. are mentioned, for example. Among these, a polar group containing -OH in the structure (hereinafter, sometimes referred to as an "OH-containing polar group") is preferable, a carboxy group or a hydroxyl group is more preferable, and a carboxy group is particularly preferable.

More specific examples of the acid-decomposable group include a group in which the polar group is protected by an acid-dissociable group (eg, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group).

As used herein, the term "acid dissociable group" refers to (i) a group having acid dissociation in which the bond between the acid dissociable group and an atom adjacent to the acid dissociable group can be cleaved by the action of an acid, or ( ii) Both groups of a group capable of cleaving a bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by further decarboxylation after cleavage of some bonds by the action of an acid say

The acid-dissociable group constituting the acid-dissociable group must be a group having a lower polarity than the polar group formed by dissociation of the acid-dissociable group, and thus, when the acid-dissociable group is dissociated by the action of an acid, the acid-dissociable group A polar group with a higher polarity is generated and the polarity is increased. As a result, the polarity of the whole component (A1) increases. As the polarity increases, the solubility in the developer is relatively changed, so that solubility is increased when the developer is an alkaline developer, and solubility is reduced when the developer is an organic developer.

Examples of the acid dissociable group include those that have been proposed as an acid dissociable group in base resins for chemically amplified resist compositions.

As acid-dissociable groups for base resins for chemically amplified resist compositions, specifically, "acetal-type acid-dissociable groups", "tertiary alkyl ester-type acid-dissociable groups", and "tertiary classes" are described below. alkyloxycarbonyl acid dissociable group".

Acetal-type acid dissociative groups:

Among the polar groups, the acid-dissociable group that protects the carboxyl group or the hydroxyl group is, for example, an acid-dissociable group represented by the following general formula (a1-r-1) (hereinafter referred to as “acetal-type acid-dissociable group”). can be heard

[Formula 1]

[Wherein, Ra' ¹ and Ra' ² are a hydrogen atom or an alkyl group. Ra' ³ is a hydrocarbon group, and Ra' ³ may combine with any of Ra' ¹ and Ra' ² to form a ring.]

In formula (a1-r-1), it is preferable that at least one is a hydrogen atom among ^{Ra' 1} and Ra' ^{2, and it is more preferable that both are a hydrogen atom.}

When Ra' ¹ or Ra' ² is an alkyl group, examples of the alkyl group include the same alkyl groups as the substituents that may be bonded to the carbon atom at the α position in the description of the α-substituted acrylic acid ester, and have 1 to The alkyl group of 5 is preferable. Specifically, a linear or branched alkyl group is preferably mentioned. More specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. are mentioned, A methyl group or an ethyl group is more preferably, a methyl group is particularly preferable.

In the formula (a1-r-1), ^{examples of the hydrocarbon group for Ra' 3} include a linear or branched alkyl group or a cyclic hydrocarbon group.

The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and still more preferably 1 or 2 carbon atoms. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, a methyl group, an ethyl group, or n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

It is preferable that carbon number is 3-10, and, as for this branched alkyl group, C3-C5 is more preferable. Specific examples thereof include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., which are isopropyl group it is preferable

When Ra' ³ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, or may be a polycyclic group or a monocyclic group.

As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.

The polycyclic group aliphatic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

When the cyclic hydrocarbon group of Ra' ³ becomes an aromatic 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. It is preferable that carbon number of an aromatic ring is 5-30, C5-C20 is more preferable, C6-C15 is still more preferable, C6-C12 is especially preferable. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group for Ra' ³ include a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); a group in which one hydrogen atom is removed from an aromatic compound containing two or more aromatic rings (eg, biphenyl, fluorene, etc.); A group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (eg, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, 2 -arylalkyl groups, such as a naphthylethyl group, etc.) etc. are mentioned. It is preferable that carbon number of the alkylene group couple|bonded with the said aromatic hydrocarbon ring or aromatic heterocyclic ring is 1-4, It is more preferable that it is C1-C2, It is especially preferable that it is C1.

The cyclic hydrocarbon group for Ra' ^{3 may have a substituent.} Examples of this substituent include -R ^P1 , -R ^P2 -OR ^P1 , -R ^P2 -CO-R ^P1 , -R ^P2 -CO-OR ^P1 , -R ^P2 -O-CO-R ^P1 , - R ^P2 -OH, -R ^P2 -CN, or -R ^P2 -COOH (hereinafter ^{referred to as "Ra 05 ,} " encompassing these substituents), and the like.

Here, R ^P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Further, R ^P2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. However, part or all of the hydrogen atoms of the chain saturated hydrocarbon group, alicyclic saturated hydrocarbon group, and aromatic hydrocarbon group of ^{R P1} and R ^{P2 may be substituted with fluorine atoms.} The said aliphatic cyclic hydrocarbon group may have 1 or more types of the said substituent individually by 1 type, and may have each 1 or more types of multiple types among the said substituents.

Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms 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, and a decyl group.

Examples of the monovalent aliphatic saturated hydrocarbon group having 3 to 20 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group. monocyclic aliphatic saturated hydrocarbon groups such as; Bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group, tetracyclo[6.2.1.13,6.02,7]dodecanyl group, adecanyl group Polycyclic aliphatic saturated hydrocarbon groups, such as a dantyl group, are mentioned.

Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups in which one hydrogen atom is removed from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

When Ra' ³ combines with any of Ra' ¹ and Ra' ² to form a ring, the cyclic group is preferably a 4 to 7 membered ring, more preferably a 4 to 6 membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

A tertiary alkyl ester type acid dissociable group:

Among the polar groups, examples of the acid dissociable group protecting the carboxy group include an acid dissociable group represented by the following general formula (a1-r-2).

In addition, among the acid-dissociable groups represented by the following formula (a1-r-2), those constituted by an alkyl group are hereinafter sometimes referred to as "tertiary alkyl ester-type acid-dissociable groups" for convenience.

[Formula 2]

[Wherein, Ra' ⁴ to Ra' ⁶ are each a hydrocarbon group, and Ra' ⁵ and Ra' ⁶ may be bonded to each other to form a ring.]

Examples of the hydrocarbon group for Ra' ⁴ include a linear or branched alkyl group, a chain or cyclic alkenyl group, and a cyclic hydrocarbon group.

Ra ^'4 linear or branched alkyl group, a cyclic hydrocarbon group in the (single ring sentence an aliphatic hydrocarbon group, a polycyclic group an aliphatic hydrocarbon group, an aromatic hydrocarbon group), the Ra' include the same as ³ can

The chain or cyclic alkenyl group for Ra' ⁴ is preferably an alkenyl group having 2 to 10 carbon atoms.

Examples of the hydrocarbon group for Ra' ⁵ and Ra' ^{6 include} the same as those for ^{Ra' 3 above.}

When Ra' ⁵ and Ra' ⁶ are bonded to each other to form a ring, a group represented by the following general formula (a1-r2-1), a group represented by the following general formula (a1-r2-2), and a group represented by the following general formula (a1) The group represented by -r2-3) is mentioned preferably.

On the other hand, when Ra' ⁴ to Ra' ⁶ are not mutually bonded and are independent hydrocarbon groups, a group represented by the following general formula (a1-r2-4) is preferably exemplified.

[Formula 3]

[In the formula (a1-r2-1), Ra' ¹⁰ represents an alkyl group having 1 to 10 carbon atoms or a group represented by the following general formula (a1-r2-r1). Ra' ¹¹ represents a group forming an aliphatic cyclic group together with the carbon atom to which Ra' ^{10 is bonded.} In formula (a1-r2-2), Ya is a carbon atom. Xa is a group which forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of this cyclic hydrocarbon group may be substituted. Ra ⁰¹ to Ra ⁰³ are each independently a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group and the alicyclic saturated hydrocarbon group may be substituted. Two or more of Ra ⁰¹ to Ra ⁰³ may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group which together with Yaa forms an aliphatic cyclic group. Ra ⁰⁴ is an aromatic hydrocarbon group which may have a substituent. Equation (a1-r2-4) of, Ra is ^'12 and Ra' ^13, each independently, a monovalent chain-like saturated hydrocarbon group or a hydrogen atom of 1 to 10 carbon atoms. A part or all of the hydrogen atoms of the chain saturated hydrocarbon group may be substituted. Ra' ¹⁴ is a hydrocarbon group which may have a substituent. * indicates a bond hand.]

[Formula 4]

[In the formula, Ya ⁰ is a quaternary carbon atom. Ra ⁰³¹ , Ra ^{032 ,} and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. However, ^{at least one of Ra 031} , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one polar group.]

In the above formula (a1-r2-1), the alkyl group having 1 to 10 carbon atoms for ^{Ra' 10} is the linear or branched alkyl group for ^{Ra' 3 in the formula (a1-r-1).} group is preferred. Ra ^'10 is preferably an alkyl group having 1 to 5 carbon atoms.

In the formula (a1-r2-r1), Ya ⁰ is a quaternary carbon atom. That is, there are 4 neighboring carbon atoms bonded to ^{Ya 0 (carbon atom).}

In the formula (a1-r2-r1), Ra ⁰³¹ , Ra ^{032 ,} and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. ^Examples of the hydrocarbon group for Ra ⁰³¹ , Ra ⁰³² and Ra 033 each independently include a linear or branched alkyl group, a chain or cyclic alkenyl group, and a cyclic hydrocarbon group.

Ra ^031, is an alkyl group of a linear in the ⁰³² Ra and ⁰³³ Ra, is a carbon number of 1-5 is preferable, and the more preferred, and 1 or 2 is more preferably 1-4. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, a methyl group, an ethyl group, or n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

⁰³¹ Ra, alkyl, branched in the ⁰³² Ra and ⁰³³ Ra is preferably a carbon number of 3-10, and more preferably 3-5. Specific examples thereof include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., which are isopropyl group it is preferable

The ^{chain or cyclic alkenyl group in Ra 031} , Ra ⁰³² and Ra ⁰³³ is preferably an alkenyl group having 2 to 10 carbon atoms.

The ^{cyclic hydrocarbon group in Ra 031} , Ra ⁰³² and Ra ⁰³³ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.

As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.

The polycyclic group aliphatic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

The aromatic hydrocarbon group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ 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. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are still more preferable, 6-12 are especially preferable. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Specific examples of the aromatic hydrocarbon group include a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); a group in which one hydrogen atom is removed from an aromatic compound containing two or more aromatic rings (eg, biphenyl, fluorene, etc.); A group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (eg, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, 2 -arylalkyl groups, such as a naphthylethyl group, etc.) etc. are mentioned. It is preferable that carbon number of the alkylene group couple|bonded with the said aromatic hydrocarbon ring or aromatic heterocyclic ring is 1-4, It is more preferable that it is 1-2, It is especially preferable that it is 1.

When the ^{hydrocarbon group represented by Ra 031} , Ra ⁰³² and Ra ⁰³³ is substituted, the substituent includes, for example, a hydroxyl group, a carboxy group, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, etc.), an alkoxy group. (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, etc.), an alkyloxy carbonyl group, etc. are mentioned.

Among the above, ^{the hydrocarbon group which may have a substituent in Ra 031} , Ra ⁰³² and Ra ⁰³³ is preferably a linear or branched alkyl group which may have a substituent, and more preferably a linear alkyl group. .

However, ^{at least one of Ra 031} , Ra ^{032 ,} and Ra ⁰³³ is a hydrocarbon group having at least a polar group.

The "hydrocarbon group having a polar group" includes both those in which the methylene group (-CH ₂ -) constituting the hydrocarbon group is substituted with a polar group or in which at least one hydrogen atom constituting the hydrocarbon group is substituted with a polar group.

As such "a hydrocarbon group having a polar group", a functional group represented by the following general formula (a1-p1) is preferable.

[Formula 5]

[In the formula, Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms. Ra ⁰⁸ represents a divalent linking group containing a hetero atom. Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms. n _p0 is an integer of 1 to 6.]

In the formula (a1-p1), Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms. Ra ⁰⁷ has 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, still more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms.

The hydrocarbon group for Ra ⁰⁷ is preferably a chain or cyclic aliphatic hydrocarbon group, and more preferably a chain hydrocarbon group.

Ra ⁰⁷ is, for example, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1 ,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12- linear alkanediyl groups such as diyl groups; Propane-1,2-diyl group, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4 -branched-chain alkanediyl groups, such as a diyl group; cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group and cyclooctane-1,5-diyl group; polycyclic divalent groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group An alicyclic hydrocarbon group etc. are mentioned.

Among the above, an alkanediyl group is preferable and a linear alkanediyl group is more preferable.

In the formula (a1-p1), Ra ⁰⁸ represents a divalent linking group containing a hetero atom.

As Ra ⁰⁸ , for example, -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=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- etc. are mentioned.

Among these, -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O- are preferable from the point of solubility with respect to a developing solution, -O-, -C(=O)- is particularly preferred.

In the formula (a1-p1), Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms. Ra ⁰⁶ has 1 to 12 carbon atoms, and from the viewpoint of solubility in a developing solution, preferably 1 to 8 carbon atoms, more preferably 1 to 5 carbon atoms, still more preferably 1 to 3 carbon atoms, and still more preferably 1 or 2 carbon atoms. Especially preferred, and 1 is most preferred.

Examples ^{of the hydrocarbon group for Ra 06} include a chain hydrocarbon group, a cyclic hydrocarbon group, or a hydrocarbon group in which a chain and a cyclic form are combined.

Examples of the chain hydrocarbon group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- A heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, etc. are mentioned.

An alicyclic hydrocarbon group may be sufficient as a cyclic hydrocarbon group, and an aromatic hydrocarbon group may be sufficient as it.

The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a methylcyclohexyl group. and cycloalkyl groups such as dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a 2-alkyladamantan-2-yl group, a 1-(adamantan-1-yl)alkan-1-yl group, A norbornyl group, a methyl norbornyl group, an isobornyl group, etc. are mentioned.

Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, bi and a phenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

Ra ⁰⁶ is preferably a chain hydrocarbon group, more preferably an alkyl group, still more preferably a linear alkyl group, from the viewpoint of solubility in a developer.

In said formula (a1-p1), n _p0 is an integer of 1-6, the integer of 1-3 is preferable, 1 or 2 is more preferable, and 1 is still more preferable.

Below, the specific example of the hydrocarbon group which has a polar group at least is shown.

In the following formulas, * is a bond bonded to a ^{quaternary carbon atom (Ya 0 ).}

[Formula 6]

In the formula (a1-r2-r1), among Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the number of hydrocarbon groups having at least a polar group is one or more. is suitably determined, for example, ⁰³¹ Ra, ⁰³² Ra and ⁰³³ Ra 1 and one or two of the individual is preferably, and particularly preferably 1 dog.

The hydrocarbon group having at least a polar group may have a substituent other than the polar group. As this substituent, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, etc.) and a C1-C5 halogenated alkyl group are mentioned, for example.

In formula (a1-r2-1), Ra' ¹¹ (aliphatic cyclic group formed together with the carbon atom to which Ra' ¹⁰ is bonded) is a monocyclic group or polyvalent group ^{of Ra' 3 in formula (a1-r-1)} The group mentioned as an aliphatic hydrocarbon group which is a cyclic group is preferable.

In the formula (a1-r2-2), the cyclic hydrocarbon group formed by Xa together with Ya is a cyclic monovalent hydrocarbon group (aliphatic hydrocarbon ^{) for Ra' 3 in the formula (a1-r-1).} group) in which at least one hydrogen atom has been further removed from the group.

The cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. Examples of the substituent include the same substituents as the substituents that the cyclic hydrocarbon group for ^{Ra′ 3 may have.}

In the formula (a1-r2-2), as the ^{monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra 01} to Ra ⁰³ , for example, 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 decyl group, etc. are mentioned.

Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra ⁰¹ to Ra ⁰³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cycloox group. monocyclic aliphatic saturated hydrocarbon groups such as a tyl group, a cyclodecyl group, and a cyclododecyl group; Bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group, tetracyclo[6.2.1.13,6.02,7]dodecanyl group, adecanyl group Polycyclic aliphatic saturated hydrocarbon groups, such as a damantyl group, etc. are mentioned.

Among them, Ra ⁰¹ to Ra ⁰³ are preferably a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms from the viewpoint of easiness in synthesizing the monomer compound that induces the structural unit (a1), and among them, a hydrogen atom , a methyl group and an ethyl group are more preferable, and a hydrogen atom is particularly preferable.

Examples of the substituent included in the chain saturated hydrocarbon group represented by Ra ⁰¹ to Ra ⁰³ or the alicyclic saturated hydrocarbon group include the same groups as those of ^{Ra 05 described above.}

Examples of the group containing a carbon-carbon double bond formed by bonding two or more of Ra ⁰¹ to Ra ⁰³ to form a cyclic structure include, for example, a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, and a methyl group. A cyclohexenyl group, a cyclopentylideneethenyl group, a cyclohexylideneethenyl group, etc. are mentioned. Among these, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneethenyl group are preferable from a viewpoint of the synthetic|combination easiness of the monomeric compound which guide|induced the structural unit (a1).

In the formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is preferably a group listed as an aliphatic hydrocarbon group that is a monocyclic group or a polycyclic group ^{of Ra' 3 in the formula (a1-r-1).} Do.

In the formula (a1-r2-3), examples ^{of the aromatic hydrocarbon group for Ra 04} include groups in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra ⁰⁴ is preferably a group in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms are removed from benzene, naphthalene, anthracene or phenanthrene, benzene, A group in which at least one hydrogen atom has been removed from naphthalene or anthracene is more preferred, a group obtained by removing at least one hydrogen atom from benzene or naphthalene is particularly preferred, and a group obtained by removing at least one hydrogen atom from benzene is most preferred.

^{Examples of the substituent that Ra 04} in the formula (a1-r2-3) may have include, for example, a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, etc.); An alkoxy group (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, etc.), an alkyloxy carbonyl group, etc. are mentioned.

Equation (a1-r2-4) of, Ra is ^'12 and Ra' ^13, each independently, a monovalent chain-like saturated hydrocarbon group or a hydrogen atom of 1 to 10 carbon atoms. Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms for Ra' ¹² and Ra' ¹³ include the same monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms for ^{Ra 01} to Ra ^{03 described above.} can be heard A part or all of the hydrogen atoms of the chain saturated hydrocarbon group may be substituted.

Among them, Ra' ¹² and Ra' ¹³ are preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, still more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

When the ^{chain saturated hydrocarbon group represented by Ra' 12} and Ra' ¹³ is substituted, examples of the substituent include the same groups as those of ^{Ra 05 described above.}

In formula (a1-r2-4), Ra' ¹⁴ is a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group for Ra' ¹⁴ include a linear or branched alkyl group or a cyclic hydrocarbon group.

It is preferable that carbon number is 1-5, as for the linear alkyl group in Ra' ^{14, 1-4 are more preferable, and 1 or 2 is still more preferable.} Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, a methyl group, an ethyl group, or n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

It is preferable that carbon number is 3-10, and, as for the branched alkyl group in Ra' ^{14, 3-5 are more preferable.} Specific examples thereof include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., which are isopropyl group it is preferable

When Ra' ¹⁴ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, or may be a polycyclic group or a monocyclic group.

As the aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.

The polycyclic group aliphatic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

Examples of the aromatic hydrocarbon group for Ra' ¹⁴ include the same aromatic hydrocarbon group for Ra ⁰⁴ . Among them, Ra' ¹⁴ is preferably a group in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms are removed from benzene, naphthalene, anthracene or phenanthrene, benzene , a group excluding at least one hydrogen atom from naphthalene or anthracene is more preferred, a group excluding at least one hydrogen atom from naphthalene or anthracene is particularly preferred, and a group excluding at least one hydrogen atom from naphthalene is most preferred.

Examples of ^{the substituent which Ra' 14} may have include the same substituents as the substituent which Ra ⁰⁴ may have.

When Ra' ¹⁴ in the formula (a1-r2-4) is a naphthyl group, the position bonded to the tertiary carbon atom in the formula (a1-r2-4) is at the 1-position or 2-position of the naphthyl group. Any location may be sufficient.

When Ra' ¹⁴ in the formula (a1-r2-4) is an anthryl group, the positions bonded to the tertiary carbon atom in the formula (a1-r2-4) are the 1-position and 2-position of the anthryl group. Or any position of 9 positions may be sufficient.

Specific examples of the group represented by the formula (a1-r2-1) are given below.

[Formula 7]

[Formula 8]

[Formula 9]

Specific examples of the group represented by the formula (a1-r2-2) are given below.

[Formula 10]

[Formula 11]

[Formula 12]

Specific examples of the group represented by the formula (a1-r2-3) are given below.

[Formula 13]

Specific examples of the group represented by the formula (a1-r2-4) are given below.

[Formula 14]

Tertiary alkyloxycarbonyl acid dissociative group:

Among the polar groups, the acid dissociable group for protecting the hydroxyl group is, for example, an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as “tertiary alkyloxycarbonyl acid dissociable group” for convenience) There is) can be mentioned.

[Formula 15]

[Wherein, Ra' ⁷ to Ra' ⁹ are each an alkyl group.]

Formula (a1-r-3) of, Ra ^'7 ~ Ra' ^9, it is each an alkyl group of 1 to 5 carbon atoms are preferred, and more preferred is an alkyl group having 1 to 3 carbon atoms.

Moreover, it is preferable that total carbon number of each alkyl group is 3-7, It is more preferable that it is C3-C5, It is most preferable that it is C3-C4.

The structural unit (a1) preferably contains an acid dissociable group represented by the general formula (a1-r-2) from the viewpoint of suppressing a decrease in the light transmittance in the thick resist film, and the general formula (a1) It is more preferable to include an acid dissociable group represented by -r2-4). In the general formula (a1-r2-4), Ra' ¹² and Ra' ¹³ are each independently preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group more preferably, a methyl group is particularly preferable. In the general formula (a1-r2-4), Ra' ¹⁴ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, still more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. Do.

As the structural unit (a1), a structural unit derived from an acrylic acid ester 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 acrylamide, a structural unit derived from hydroxystyrene or a hydroxystyrene derivative Hydrogen in -C(=O)-OH of a structural unit in which at least a part of hydrogen atoms in the hydroxyl group of the unit is protected by a substituent containing the acid-decomposable group, or a structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative and structural units in which at least a part of atoms are protected by a substituent containing the acid-decomposable group.

As the structural unit (a1), among the above, a structural unit derived from an acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent is preferable. As a preferable specific example of such a structural unit (a1), the structural unit represented by the following general formula (a1-1) or (a1-2) is mentioned.

[Formula 16]

[In the formula, 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. Va ¹ is a divalent hydrocarbon group which may have an ether bond. n _a1 is an integer of 0-2. Ra ¹ is an acid dissociable group represented by the general formula (a1-r-1) or (a1-r-2). Wa ¹ is n _a2 + monovalent hydrocarbon group, n _a2 is an integer of 1 to 3, and Ra ² is an acid dissociable group represented by the above general formula (a1-r-1) or (a1-r-3). .]

In the formula (a1-1), the C1-C5 alkyl group for R is preferably a C1-C5 linear or branched alkyl group, specifically, a methyl group, an ethyl group, a propyl group, and isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as this halogen atom, A fluorine atom is especially preferable.

As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferable.

In the formula (a1-1), the ^{divalent hydrocarbon group for Va 1} may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The ^{aliphatic hydrocarbon group as the divalent hydrocarbon group in Va 1} 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, or an aliphatic hydrocarbon group having a ring in its structure.

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and 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.

The branched chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched chain aliphatic hydrocarbon group is preferably a branched chain alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkylmethylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{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 -, -C(CH ₂ CH _{3) 2} -CH ₂ - alkyl group such as ethylene; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -, etc. are mentioned.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group excluding two hydrogen atoms from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group , a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as the linear or branched aliphatic hydrocarbon group.

It is preferable that carbon number is 3-20, and, as for the said alicyclic hydrocarbon group, it is more preferable that it is C3-C12.

Polycyclic type may be sufficient as the said alicyclic hydrocarbon group, and monocyclic type may be sufficient as it. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

The aromatic hydrocarbon group as the divalent hydrocarbon group in ^{Va 1 is a hydrocarbon group having an aromatic ring.}

It is preferable that carbon number of such an aromatic hydrocarbon group is 3-30, It is more preferable that it is 5-30, 5-20 are still more preferable, 6-15 are especially preferable, and 6-12 are the most preferable. However, carbon number in a substituent shall not be included in the carbon number. Specific examples of the aromatic ring included in the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms are removed from the aromatic hydrocarbon ring (arylene group); A group in which one hydrogen atom of the group (aryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring is substituted with an alkylene group (eg, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group) , a group in which one hydrogen atom is further removed from the aryl group in an arylalkyl group such as 1-naphthylethyl group and 2-naphthylethyl group). It is preferable that carbon number of the said alkylene group (the alkyl chain in an arylalkyl group) is 1-4, It is more preferable that it is 1-2, It is especially preferable that it is 1.

In the formula (a1-1), Ra ¹ is an acid dissociable group represented by the formula (a1-r-1) or (a1-r-2).

In said formula (a1-1), n _a1 is an integer of 0-2. 0 or 1 is preferable and, as for n _{a1, 0 is more preferable.}

In the formula (a1-2), _{the n a2} ^{+ monovalent hydrocarbon group in Wa 1} may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. The aliphatic hydrocarbon group is a combination of a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group including a ring in the structure, or a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group including a ring in the structure. You can pick up one. 2-4 valence is preferable and, as for said n _a2 +1 value, 2 or 3 valence is more preferable.

In the formula (a1-2), Ra ² is an acid dissociable group represented by the general formula (a1-r-1) or (a1-r-3).

Specific examples of the structural unit represented by the formula (a1-1) are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

Specific examples of the structural unit represented by the formula (a1-2) are shown below.

[Formula 28]

(A1) The number of structural units (a1) which a component has may be 1 type, or 2 or more types may be sufficient as it.

As the structural unit (a1), the structural unit represented by the above formula (a1-1) is more preferable because the characteristics (sensitivity, shape, etc.) in lithography by electron beam or EUV are more likely to become higher.

Among these, as a structural unit (a1), it is especially preferable that the structural unit represented by the following general formula (a1-1-1) is included.

[Formula 29]

[Wherein, Ra ¹ ″ is an acid dissociable group represented by the general formula (a1-r2-1), (a1-r2-3) or (a1-r2-4).]

In the formula (a1-1-1), R, Va n ¹ and _a1 is the same as R, ¹ and Va n _a1 in the formula (a1-1).

The description of the acid dissociable group represented by the general formula (a1-r2-1), (a1-r2-3) or (a1-r2-4) is as described above. Ra ¹ " is preferably an acid-dissociable group represented by the general formula (a1-r2-4) from the viewpoint of maintaining transparency in the thick-film resist film. Ra' in the general formula (a1-r2-4) ^{Preferred examples of 12} , Ra' ¹³ , and Ra' ¹⁴ are as described above.

(A1) The ratio of the structural unit (a1) in the component is preferably from 5 to 80 mol%, and from 10 to 75 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). More preferably, 15 to 70 mol% is still more preferable, and 20 to 60 mol% is particularly preferable.

When the ratio of the structural unit (a1) is equal to or greater than the lower limit of the above-described preferred range, lithographic properties such as sensitivity, resolution, and roughness improvement are improved. On the other hand, if it is below the upper limit of the said preferable range, a balance with other structural units can be taken, and various lithographic characteristics become favorable.

≪Other constituent units≫

(A1) In addition to the structural unit (a1) mentioned above, a component may have another structural unit as needed.

Examples of the other structural unit include a structural unit (a2) including a lactone-containing cyclic group, -SO _{2 --containing cyclic group, or carbonate-containing cyclic group;} structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group; a structural unit (a4) containing an acid non-dissociable aliphatic cyclic group; structural unit (a10) represented by general formula (a10-1) mentioned later; and structural units (st) derived from styrene or derivatives thereof.

Regarding the constituent unit (a2):

The component (A1) is, in addition to the structural unit (a1), a structural unit (a2) further comprising a lactone-containing cyclic group, -SO ₂ -containing cyclic group or carbonate-containing cyclic group (provided that the structural unit (a1) (excluding those corresponding to ) may have.

The lactone-containing cyclic group, -SO ₂ --containing cyclic group or carbonate-containing cyclic group in the structural unit (a2) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used to form the resist film. . In addition, by having the structural unit (a2), for example, by appropriately adjusting the acid diffusion length, increasing the adhesion of the resist film to the substrate, and appropriately adjusting the solubility at the time of development, lithographic characteristics back becomes good.

The "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -O-C(=O)- in its cyclic skeleton. The lactone ring is counted as the first ring, and when it is only a lactone ring, 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-containing cyclic group in the structural unit (a2) is not particularly limited, and any arbitrary group can be used. Specific examples thereof include groups represented by the following general formulas (a2-r-1) to (a2-r-7).

[Formula 30]

[wherein, Ra' ²¹ is each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ - containing cyclic group; A" may contain an oxygen atom (-O-) or a sulfur atom (-S-) an alkylene group having 1 to 5 carbon atoms, an oxygen atom or a sulfur atom, n' is an integer of 0 to 2, and m' is 0 or 1.]

In the general formulas (a2-r-1) to (a2-r-7), ^{the alkyl group for Ra' 21} is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group, etc. are mentioned. Among these, a methyl group or an ethyl group is preferable, and a methyl group is especially preferable.

The alkoxy group for Ra' ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms. It is preferable that the alkoxy group is linear or branched. Specific examples include groups in which the alkyl group mentioned as the alkyl group for ^{Ra' 21 and an oxygen atom (-O-) are linked.}

As a halogen atom in Ra' ²¹ , a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Ra 'with a halogenated alkyl group in the ^21, wherein Ra' may be a group in which some or all of the hydrogen atoms of the alkyl group in ²¹ with the halogen atoms. The halogenated alkyl group is preferably a fluorinated alkyl group, particularly preferably a perfluoroalkyl group.

In -COOR" and -OC(=O)R" for Ra' ²¹ , R" is all a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group.

The alkyl group for R" may be linear, branched or cyclic, and preferably has 1 to 15 carbon atoms.

When R" is a linear or branched alkyl group, it is preferably from 1 to 10 carbon atoms, more preferably from 1 to 5 carbon atoms, particularly preferably a methyl group or an ethyl group.

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, substituted with a fluorine atom or a fluorinated alkyl group A group in which one or more hydrogen atoms are removed from a monocycloalkane that may or may not be; a group in which one or more hydrogen atoms are removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. More specifically, a group in which one or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. and groups in which one or more hydrogen atoms have been removed from polycycloalkane.

Examples of the lactone-containing cyclic group for R" include the same groups as the groups represented by the general formulas (a2-r-1) to (a2-r-7).

Examples of the carbonate-containing cyclic group for R" are the same as the carbonate-containing cyclic groups described later, and specific examples thereof include groups represented by the general formulas (ax3-r-1) to (ax3-r-3).

R "-SO ₂ of the-containing cyclic group, which will be described later -SO ₂ - containing cyclic group with the same and, specifically, each by the formula (a5-r-1) ~ (a5-r-4) A group that represents can be mentioned.

The hydroxyalkyl group for Ra' ²¹ preferably has 1 to 6 carbon atoms, and specific examples include groups in which at least one hydrogen atom of the alkyl group for ^{Ra' 21 is substituted with a hydroxyl group.}

In the general formulas (a2-r-2), (a2-r-3), and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A” is linear or branched. An alkylene group is preferable, and examples include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include the alkylene group and a group in which -O- or -S- is interposed between the terminals or carbon atoms of, for example, O-CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH _2- S-CH ₂ -, etc. As A", a C1-C5 alkylene group or -O- is preferable, a C1-C5 alkylene group is more preferable, A methylene group is the most preferable.

Specific examples of groups each represented by the general formulas (a2-r-1) to (a2-r-7) below are given.

[Formula 31]

[Formula 32]

"-SO ₂ - containing cyclic group" refers to a cyclic group containing a ring containing _{-SO 2} - in its cyclic skeleton, specifically, the sulfur atom (S) in _{-SO 2 - is a cyclic group} It is a cyclic group that forms part of the ring skeleton of _{A ring containing -SO 2} - in the ring skeleton is counted as the first ring, and when it is only the ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The -SO ₂ - containing cyclic group may be a monocyclic group or a polycyclic group. The -SO ₂ - containing cyclic group is, in particular, a cyclic group containing -O-SO ₂ - in its ring backbone, that is, a sultone in which -OS- in -O-SO ₂ - forms a part of the ring backbone It is preferable that it is a cyclic group containing a ring.

More specifically, examples of the -SO ₂ - containing cyclic group include groups represented by the following general formulas (a5-r-1) to (a5-r-4).

[Formula 33]

[wherein, Ra' ⁵¹ is each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group; A" is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom, oxygen atom or sulfur atom, and n' is an integer of 0 to 2.]

In the general formulas (a5-r-1) to (a5-r-2), A" is the general formulas (a2-r-2), (a2-r-3), (a2-r-5) Same as "A" in

The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R" and hydroxyalkyl group for Ra' ^{51 are, respectively, from the above general formulas (a2-r-1) to (a2).} -r-7), the same as those mentioned in the description for ^{Ra' 21 can be mentioned.}

Specific examples of groups each represented by the general formulas (a5-r-1) to (a5-r-4) below are given. "Ac" in a formula represents an acetyl group.

[Formula 34]

[Formula 35]

[Formula 36]

The "carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -O-C(=O)-O- in its cyclic skeleton. The carbonate ring is counted as the first ring, and when it is only a carbonate ring, it is a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.

It does not specifically limit as a carbonate ring containing cyclic group, Any arbitrary thing can be used. Specific examples thereof include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

[Formula 37]

[wherein, Ra' x ³¹ is each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group; A" is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom, oxygen atom or sulfur atom, p' is an integer of 0 to 3, and q' is 0 or 1.]

In the general formulas (ax3-r-2) to (ax3-r-3), A" is the general formulas (a2-r-2), (a2-r-3), (a2-r-5) Same as "A" in

The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group for Ra' ^{31 are, respectively, from the above general formulas (a2-r-1) to (a2).} -r-7), the same as those mentioned in the description for ^{Ra' 21 can be mentioned.}

Specific examples of groups each represented by the general formulas (ax3-r-1) to (ax3-r-3) below are given.

[Formula 38]

As the structural unit (a2), a structural unit derived from an acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent is preferable.

It is preferable that such a structural unit (a2) is a structural unit represented by the following general formula (a2-1).

[Formula 39]

[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. Ya ²¹ is a single bond or a divalent linking group. La ²¹ is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO- or -CONHCS-, and R' represents a hydrogen atom or a methyl group. However ^{, when La 21} is -O-, Ya ²¹ does not become -CO-. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group.]

In the formula (a2-1), R is the same as above. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

In the formula (a2-1), the ^{divalent linking group for Ya 21} is not particularly limited, but preferably includes a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like. .

· A divalent hydrocarbon group which may have a substituent:

When Ya ²¹ is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

... aliphatic hydrocarbon group for ^{Ya 21}

An aliphatic hydrocarbon group means a hydrocarbon group which does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and it is usually preferable that it is saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group having a ring in its structure.

... linear or branched aliphatic hydrocarbon group

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and 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.

The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

The branched chain aliphatic hydrocarbon group is preferably a branched chain alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkylmethylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{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 -, -C(CH ₂ CH _{3) 2} -CH ₂ - alkyl group such as ethylene; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -, etc. are mentioned.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

... an aliphatic hydrocarbon group containing a ring in its structure

Examples of the aliphatic hydrocarbon group containing a ring in its structure include a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms are removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a hetero atom in the ring structure, and the cyclic aliphatic group and a group in which a hydrocarbon group is bonded to a terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as 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 a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane 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. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.

As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are more preferable.

The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more 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 time, an ethoxy group is more preferable.

As a halogen atom as said substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include a group in which some or all of the hydrogen atoms of the alkyl group are 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 a substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O- are preferable. .

··Aromatic hydrocarbon group for ^{Ya 21}

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. It is preferable that carbon number of an aromatic ring is 5-30, C5-C20 is more preferable, C6-C15 is still more preferable, C6-C12 is especially preferable. However, carbon number in a substituent shall not be included in the carbon number.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms are removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group in which two hydrogen atoms are removed from an aromatic compound containing two or more aromatic rings (eg, biphenyl, fluorene, etc.); A group in which one hydrogen atom of a group (aryl group or heteroaryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (eg, benzyl group, phenethyl group, 1-naph group in which one hydrogen atom is further removed from the aryl group in arylalkyl groups, such as a tylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group) etc. are mentioned. It is preferable that carbon number of the alkylene group couple|bonded with the said aryl group or heteroaryl group is 1-4, It is more preferable that it is C1-C2, It is especially preferable that it is C1.

As for the said aromatic hydrocarbon group, the hydrogen atom which the said aromatic hydrocarbon group has may be substituted by the substituent. For example, the hydrogen atom couple|bonded with the aromatic ring in the said aromatic hydrocarbon group may be substituted by the substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

Examples of the alkoxy group, halogen atom and halogenated alkyl group as the substituent include those exemplified as substituents for substituting a hydrogen atom in the cyclic aliphatic hydrocarbon group.

· A divalent linking group containing a hetero atom:

When Ya ²¹ is a divalent linking group containing a hetero atom, the linking group is preferably -O-, -C(=O)-O-, -OC(=O)-, -C(=O)- , -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with substituents, such as an alkyl group and an acyl group. ), -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, general formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C(= O)-O-, -C(=O)-OY ²¹ -, -[Y ²¹ -C(=O)-O] _m" -Y ²² -, -Y ²¹ -OC(=O)-Y ²² - or a group represented by ^{-Y 21} -S(=O) ₂ -OY ^{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 to 3.] and the like.

The divalent linking group containing the hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)- In this case, H may be substituted with substituents, such as an alkyl group and an acyl group. It is preferable that carbon number is 1-10, as for the substituent (an alkyl group, an acyl group, etc.), it is more preferable that it is 1-8, It is especially preferable that it is 1-5.

Formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-OY ²¹ -, -[Y ²¹ -C(=O )-O] _m" -Y ²² -, -Y ²¹ -OC(=O)-Y ²² - or -Y ²¹ -S(=O) ₂ -OY ²² -, wherein Y ²¹ and Y ²² are each independently is a divalent hydrocarbon group which may have a substituent.The divalent hydrocarbon group includes the same as (divalent hydrocarbon group which may have a substituent) in the description of the divalent linking group in ^{Ya 21 above.} .

As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is still more preferable, and a methylene group or an ethylene group is particularly preferable.

As Y ²² , a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group, or an alkylmethylene group is more preferable. A C1-C5 linear alkyl group is preferable, as for the alkyl group in this alkylmethylene group, a C1-C3 linear alkyl group is more preferable, A methyl group is the most preferable.

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, more preferably 0 or 1 and 1 is particularly preferred. That is, the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² - is particularly preferably a group represented by the formula -Y ²¹ -C(=O)-OY ^{22 -.} , a group represented by the formula -(CH ₂ ) _a' -C(=O)-O-(CH ₂ ) _b' - is preferable, wherein a' is an integer of 1 to 10, and 1 to 8 An integer is preferable, an integer of 1 to 5 is more preferable, 1 or 2 is still more preferable, and most preferably 1. b' is an integer of 1 to 10, preferably an integer of 1 to 8, 1 The integer of -5 is more preferable, 1 or 2 is still more preferable, and 1 is the most preferable.

Among the above, Ya ²¹ is preferably a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof. Do.

In the formula (a2-1), Ra ²¹ is a lactone-containing cyclic group, —SO ₂ —containing cyclic group, or carbonate-containing cyclic group.

As the lactone-containing cyclic group, -SO ₂ ^{- containing cyclic group, and carbonate-containing cyclic group for Ra 21} , each group represented by the above general formulas (a2-r-1) to (a2-r-7); A group each represented by the general formulas (a5-r-1) to (a5-r-4) and a group each represented by the general formulas (ax3-r-1) to (ax3-r-3) are preferably exemplified.

Among them, a lactone-containing cyclic group or a -SO ₂ - containing cyclic group is preferable, and the general formulas (a2-r-1), (a2-r-2), (a2-r-6) or (a5-r The groups each represented by -1) are more preferable. Specifically, the above formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r-lc Any group represented by -6-1), (r-sl-1-1), and (r-sl-1-18) is more preferable.

(A1) The number of structural units (a2) which a component has may be 1 type, or 2 or more types may be sufficient as it.

When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is 5 to 60 mol% with respect to the total (100 mol%) of all structural units constituting the component (A1). It is preferable that it is 10-60 mol%, It is more preferable that it is 20-55 mol%, It is still more preferable, 30-50 mol% is especially preferable.

When the ratio of the structural unit (a2) is equal to or greater than the preferable lower limit, the effect of containing the structural unit (a2) can be sufficiently obtained by the above-described effect, and when the proportion of the structural unit (a2) is equal to or less than the upper limit, a balance with other structural units can be achieved, , various lithographic properties become good.

For the constituent unit (a3):

(A1) component, in addition to the structural unit (a1), further contains a polar group-containing aliphatic hydrocarbon group (a3) (however, except for those corresponding to the structural unit (a1) or the structural unit (a2)) may have (A1) When component has a structural unit (a3), the hydrophilicity of (A) component becomes high, and it contributes to the improvement of resolution. In addition, the acid diffusion length can be appropriately adjusted.

Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group are substituted with fluorine atoms, and a hydroxyl group is particularly preferable.

Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be either a monocyclic group or a polycyclic group, and for example, in a resin for use in a resist composition for ArF excimer lasers, it can be appropriately selected from among many proposals.

When the cyclic group is a monocyclic group, it is more preferable that carbon number is 3 to 10. Among them, a structural unit derived from an acrylic acid ester containing a hydroxyl group, a cyano group, a carboxy group, or an aliphatic monocyclic group containing a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is more preferable. Examples of the monocyclic group include a group obtained by removing two or more hydrogen atoms from a monocycloalkane. Specific examples thereof include groups obtained by removing two or more hydrogen atoms from monocycloalkanes such as cyclopentane, cyclohexane and cyclooctane. Among these monocyclic groups, a group obtained by removing two or more hydrogen atoms from cyclopentane and a group obtained by removing two or more hydrogen atoms from cyclohexane are industrially preferable.

When the cyclic group is a polycyclic group, it is more preferable that the polycyclic group has 7 to 30 carbon atoms. Among them, a structural unit derived from an acrylic acid ester containing a hydroxyl group, a cyano group, a carboxy group, or an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is more preferable. Examples of the polycyclic group include a group in which two or more hydrogen atoms are removed from a bicycloalkane, tricycloalkane, tetracycloalkane, or the like. Specific examples thereof include groups in which two or more hydrogen atoms are removed from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane. Among these polycyclic groups, a group obtained by removing two or more hydrogen atoms from adamantane, a group obtained by removing two or more hydrogen atoms from norbornane, and a group obtained by removing two or more hydrogen atoms from tetracyclododecane are industrially preferable.

The structural unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any one can be used.

The structural unit (a3) is preferably a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and containing a polar group-containing aliphatic hydrocarbon group.

As the structural unit (a3), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, a structural unit derived from a hydroxyethyl ester of acrylic acid is preferable.

Further, as the structural unit (a3), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a polycyclic group, a structural unit represented by the following formula (a3-1), a structural unit represented by the formula (a3-2), a formula The structural unit represented by (a3-3) is mentioned as a preferable thing; In the case of a monocyclic group, the structural unit represented by Formula (a3-4) is mentioned as a preferable thing.

[Formula 40]

[wherein, R is the same as above, j is an integer of 1 to 3, k is an integer of 1 to 3, t' is an integer of 1 to 3, l is an integer of 0 to 5, and s is It is an integer from 1 to 3.]

In formula (a3-1), it is preferable that it is 1 or 2, and, as for j, it is more preferable that it is 1. When j is 2, it is preferable that the hydroxyl group is couple|bonded with the 3-position and 5-position of an adamantyl group. When j is 1, it is preferable that the hydroxyl group is couple|bonded at the 3-position of an adamantyl group. It is preferable that j is 1, and it is especially preferable that the hydroxyl group is couple|bonded at the 3-position of an adamantyl group.

In formula (a3-2), it is preferable that k is 1. It is preferable that the cyano group is couple|bonded with the 5-position or 6-position of a norbornyl group.

In formula (a3-3), it is preferable that t' is 1. l is preferably 1. s is preferably 1. As for these, it is preferable that the 2-norbornyl group or 3-norbornyl group couple|bonded with the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

In formula (a3-4), it is preferable that t' is 1 or 2. l is preferably 0 or 1. s is preferably 1. The fluorinated alkyl alcohol is preferably bonded to the 3 or 5 position of the cyclohexyl group.

(A1) The number of structural units (a3) which a component has may be 1 type, or 2 or more types may be sufficient as it.

When the component (A1) has the structural unit (a3), the proportion of the structural unit (a3) is 1 to 30 mol% with respect to the total (100 mol%) of all structural units constituting the component (A1). It is preferable, 2-25 mol% is more preferable, 5-20 mol% is still more preferable.

By making the ratio of the structural unit (a3) equal to or higher than the preferable lower limit, the effect of containing the structural unit (a3) is sufficiently obtained by the above-described effect, and if it is below the preferable upper limit, a balance with other structural units can be achieved. and various lithographic properties are improved.

Regarding the constituent unit (a4):

In addition to the structural unit (a1), the component (A1) may further have a structural unit (a4) containing an acid non-dissociable aliphatic cyclic group.

When the component (A1) has the structural unit (a4), the dry etching resistance of the formed resist pattern is improved. Moreover, the hydrophobicity of (A) component becomes high. The improvement of hydrophobicity contributes to improvement of resolution, resist pattern shape, and the like, especially in the case of a solvent development process. The "acid non-dissociable cyclic group" in the structural unit (a4) is an acid generated in the resist composition upon exposure (for example, an acid is generated from the structural unit that generates an acid upon exposure or from component (B)) ), it is a cyclic group that remains in the structural unit without dissociation even if the acid acts on it.

As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing an acid non-dissociable aliphatic cyclic group is preferable. As the cyclic group, a number of conventionally known cyclic groups used in the resin component of resist compositions such as for ArF excimer lasers and for KrF excimer lasers (preferably for KrF excimer lasers) can be used.

The cyclic group is preferably at least one selected from the group consisting of a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group and a norbornyl group from the viewpoint of industrial availability. These polycyclic groups may have a C1-C5 linear or branched alkyl group as a substituent.

Specific examples of the structural unit (a4) include structural units represented by the following general formulas (a4-1) to (a4-7).

[Formula 41]

[Wherein, R ^α is the same as above.]

(A1) The number of structural units (a4) which a component has may be 1 type or 2 or more types may be sufficient as it.

When the component (A1) has a structural unit (a4), the proportion of the structural unit (a4) is 1 to 40 mol% with respect to the total (100 mol%) of all structural units constituting the component (A1). It is preferable, and it is more preferable that it is 5-20 mol%.

By making the ratio of a structural unit (a4) more than a preferable lower limit, the effect by containing a structural unit (a4) is fully acquired, on the other hand, by setting it as below a preferable upper limit, it becomes easy to take balance with another structural unit.

For the constituent unit (a10):

The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

[Formula 42]

[In the formula, 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. Ya ^x1 is a single bond or a divalent linking group. Wa ^x1 is a (n _ax1 +1) valent aromatic hydrocarbon group. n _ax1 is an integer greater than or equal to 1.]

In said formula (a10-1), R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group.

The C1-C5 alkyl group for R is preferably a C1-C5 linear or branched alkyl group, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. are mentioned.

The halogenated alkyl group having 1 to 5 carbon atoms for R 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 halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as this halogen atom, A fluorine atom is especially 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, more preferably a hydrogen atom, a methyl group or a trifluoromethyl group from the viewpoint of industrial availability, and furthermore a hydrogen atom or a methyl group preferred, and particularly preferred is a methyl group.

In the formula (a10-1), Ya ^x1 is a single bond or a divalent linking group.

In the above formula, the ^{divalent linking group for Ya x1} is not particularly limited, and preferable examples include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like.

· A divalent hydrocarbon group which may have a substituent:

When Ya ^{x 1} is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

... aliphatic hydrocarbon group for ^{Ya x1}

An aliphatic hydrocarbon group means a hydrocarbon group which does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and it is usually preferable that it is saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group having a ring in its structure.

... linear or branched aliphatic hydrocarbon group

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and 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.

The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

The branched chain aliphatic hydrocarbon group is preferably a branched chain alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkylmethylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{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 -, -C(CH ₂ CH _{3) 2} -CH ₂ - alkyl group such as ethylene; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -, etc. are mentioned.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

... an aliphatic hydrocarbon group containing a ring in its structure

Examples of the aliphatic hydrocarbon group containing a ring in its structure include a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms are removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a hetero atom in the ring structure, and the cyclic aliphatic group includes: and a group in which a hydrocarbon group is bonded to a terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as 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 a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane 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. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, more 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, more 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 time, an ethoxy group is more preferable.

As a halogen atom as said substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include a group in which a part or all of the hydrogen atoms of the alkyl group are 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 a substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O- are preferable. .

··Aromatic hydrocarbon group for ^{Ya x1}

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. It is preferable that carbon number of an aromatic ring is 5-30, C5-C20 is more preferable, C6-C15 is still more preferable, C6-C12 is especially preferable. However, carbon number in a substituent shall not be included in the carbon number.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms are removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group in which two hydrogen atoms are removed from an aromatic compound containing two or more aromatic rings (eg, biphenyl, fluorene, etc.); A group in which one hydrogen atom of a group (aryl group or heteroaryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (eg, benzyl group, phenethyl group, 1-naph group in which one hydrogen atom is further removed from the aryl group in arylalkyl groups, such as a tylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group) etc. are mentioned. It is preferable that carbon number of the alkylene group couple|bonded with the said aryl group or heteroaryl group is 1-4, It is more preferable that it is C1-C2, It is especially preferable that it is C1.

As for the said aromatic hydrocarbon group, the hydrogen atom which the said aromatic hydrocarbon group has may be substituted by the substituent. For example, the hydrogen atom couple|bonded with the aromatic ring in the said aromatic hydrocarbon group may be substituted by the substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

Examples of the alkoxy group, halogen atom and halogenated alkyl group as the substituent include those exemplified as substituents for substituting a hydrogen atom in the cyclic aliphatic hydrocarbon group.

· A divalent linking group containing a hetero atom:

When Ya ^x1 is a divalent linking group containing a hetero atom, the linking group is preferably -O-, -C(=O)-O-, -OC(=O)-, -C(=O)- , -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with substituents, such as an alkyl group and an acyl group. ), -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, general formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C(= O)-O-, -C(=O)-OY ²¹ -, -[Y ²¹ -C(=O)-O] _m" -Y ²² -, -Y ²¹ -OC(=O)-Y ²² - or a group represented by ^{-Y 21} -S(=O) ₂ -OY ^{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 to 3.] and the like.

The divalent linking group containing the hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)- In this case, H may be substituted with substituents, such as an alkyl group and an acyl group. It is preferable that carbon number is 1-10, as for the substituent (an alkyl group, an acyl group, etc.), it is more preferable that it is 1-8, It is especially preferable that it is 1-5.

Formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-OY ²¹ -, -[Y ²¹ -C(=O )-O] _m" -Y ²² -, -Y ²¹ -OC(=O)-Y ²² - or -Y ²¹ -S(=O) ₂ -OY ²² -, wherein Y ²¹ and Y ²² are each independently , is a divalent hydrocarbon group which may have a substituent.The divalent hydrocarbon group includes the same (divalent hydrocarbon group which may have a substituent) described in the description of the divalent linking group in ^{Ya x1 above.} .

As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is still more preferable, and a methylene group or an ethylene group is particularly preferable.

As Y ²² , a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group, or an alkylmethylene group is more preferable. A C1-C5 linear alkyl group is preferable, as for the alkyl group in this alkylmethylene group, a C1-C3 linear alkyl group is more preferable, A methyl group is the most preferable.

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, more preferably 0 or 1 and 1 is particularly preferred. That is, the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² - is particularly preferably a group represented by the formula -Y ²¹ -C(=O)-OY ^{22 -.} , a group represented by the formula -(CH ₂ ) _a' -C(=O)-O-(CH ₂ ) _b' - is preferable, wherein a' is an integer of 1 to 10, and 1 to 8 An integer is preferable, an integer of 1 to 5 is more preferable, 1 or 2 is still more preferable, and most preferably 1. b' is an integer of 1 to 10, preferably an integer of 1 to 8, 1 The integer of -5 is more preferable, 1 or 2 is still more preferable, and 1 is the most preferable.

Among the above, as Ya ^x1 , a single bond, an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched alkylene group , or a combination thereof, a single bond or an ester bond [-C(=O)-O-, -OC(=O)-] is more preferable, and a single bond is still more preferable.

In the formula (a10-1), Wa ^x1 is a (n _ax1 +1) valent aromatic hydrocarbon group.

_Examples of the aromatic hydrocarbon group for Wa ^x1 include groups in which (n ax1+1) hydrogen atoms are removed from an aromatic ring. The aromatic ring here 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, C5-C20 is more preferable, C6-C15 is still more preferable, C6-C12 is especially preferable. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

The aromatic hydrocarbon group in the Wa ^x1, there may be mentioned airway, except for an aromatic compound (for example, biphenyl, fluorene, etc.) _(ax1 n + 1) hydrogen atoms from containing two or more aromatic rings.

Among the above, as Wa ^x1 _{, a group in which (n ax1} +1) hydrogen atoms are removed from benzene, naphthalene, anthracene or biphenyl is preferable, and a group in which (n _ax1 +1) hydrogen atoms are removed from benzene or naphthalene is more preferable, , a _{group excluding (n ax1} + 1) hydrogen atoms from benzene is more preferred.

Although ^{the aromatic hydrocarbon group in Wa x1} may or may not have a substituent, it is preferable not to have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group. Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent include the same groups as the substituents for the cyclic aliphatic hydrocarbon group in ^{Ya x 1 .} The Wa ^x1, when the group other than the (n _ax1 + 1) hydrogen atoms from aromatic ring, the substituent is to replace the hydrogen atoms in groups except the (n _ax1 + 1) hydrogen atoms from the aromatic ring . The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, still more preferably an ethyl group or a methyl group, and a methyl group is particularly preferred.

In the formula (a10-1), n _ax1 is an integer of 1 or more, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably 1, 2 or 3, and 1 or 2 is particularly preferred. Especially, as for n _ax1 , 1 is preferable.

Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below.

In each of the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[Formula 43]

[Formula 44]

[Formula 45]

[Formula 46]

(A1) The number of structural units (a10) which a component has may be one, or 2 or more types may be sufficient as it.

When the component (A1) has a structural unit (a10), the proportion of the structural unit (a10) in the component (A1) is 5 to (100 mol%) of all the structural units constituting the component (A1). It is preferable that it is 80 mol%, 5-75 mol% is more preferable, and 10-70 mol% is still more preferable.

By making the ratio of a structural unit (a10) more than a lower limit, a sensitivity becomes high more easily. On the other hand, by setting it as below an upper limit, it becomes easy to take balance with another structural unit.

Regarding the constituent unit (st):

The structural unit (st) is a structural unit derived from styrene or a styrene derivative. The "structural unit derived from styrene" means a structural unit constituted by cleavage of the ethylenic double bond of styrene. "Structural unit derived from a styrene derivative" means a structural unit constituted by cleavage of an ethylenic double bond of a styrene derivative.

A "styrene derivative" means a compound in which at least a part of hydrogen atoms of styrene are substituted with a substituent. As the styrene derivative, for example, one in which a hydrogen atom at the α-position of styrene is substituted with a substituent, one or more hydrogen atoms in the benzene ring of styrene substituted with a substituent, a hydrogen atom at the α-position of styrene and one of the benzene ring and the like in which two or more hydrogen atoms are substituted with a substituent.

Examples of the substituent for substituting the hydrogen atom at the α-position of styrene include an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

As said C1-C5 alkyl group, a C1-C5 linear or branched alkyl group is preferable, Specifically, a methyl group, an ethyl group, a propyl group, isopropyl group, n-butyl group, isobutyl group group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like.

The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as this halogen atom, A fluorine atom is especially preferable.

The substituent for substituting the hydrogen atom at the α-position of styrene is preferably an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or a fluorinated alkyl group having 1 to 3 carbon atoms, , from the viewpoint of industrial availability, a methyl group is more preferable.

As a substituent which substitutes the hydrogen atom of the benzene ring of styrene, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group etc. are mentioned, for example.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, more 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, more 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 time, an ethoxy group is more preferable.

As a halogen atom as said substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include a group in which a part or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms.

As a substituent which substitutes the hydrogen atom of the benzene ring of styrene, a C1-C5 alkyl group is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is still more preferable.

The structural unit (st) is preferably a structural unit derived from styrene or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, A structural unit derived from styrene or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with a methyl group is more preferable, and a structural unit derived from styrene is still more preferable.

(A1) One type or two types of structural unit (st) which a component has may be sufficient as it.

When the component (A1) has a structural unit (st), the proportion of the structural unit (st) is 1 to 30 mol% with respect to the total (100 mol%) of all structural units constituting the component (A1). It is preferable, and it is more preferable that it is 3-20 mol%.

The component (A1) contained in the resist composition may be used alone or in combination of two or more.

In the resist composition of the present embodiment, the component (A1) includes a polymer compound having a repeating structure of the structural unit (a1).

As a preferable component (A1), the polymeric compound which has a repeating structure of a structural unit (a1) and another structural unit is mentioned. As said other structural unit, a structural unit (a10), a structural unit (st), etc. are mentioned.

In addition to the combination of each of the above two structural units, further, as the third or three or more structural units, the structural units described above may be appropriately combined according to a desired effect. As a combination of three or more structural units, the combination of structural unit (a1), structural unit (a10), and structural unit (st), etc. are mentioned, for example.

Preferred examples of the component (A1) include a polymer compound having a repeating structure of a structural unit (a1) and a structural unit (a10); A polymer compound having a repeating structure of a structural unit (a1) and a structural unit (st), etc.: a polymer compound having a repeating structure of a structural unit (a1), a structural unit (a10), and a structural unit (st).

The component (A1) is obtained by dissolving a monomer inducing each structural unit in a polymerization solvent, and therein, for example, azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (for example, V-601, etc.) ) can be produced by adding a radical polymerization initiator such as a polymerization initiator.

Alternatively, in the component (A1), a monomer that induces the structural unit (a1) and, if necessary, a monomer that induces a structural unit other than the structural unit (a1) are dissolved in a polymerization solvent, and therein, the radicals as described above It can manufacture by adding a polymerization initiator, superposing|polymerizing, and performing a deprotection reaction after that.

In addition, at the time of polymerization, for example, by using in combination with a chain transfer agent such as _{HS-CH 2} -CH ₂ -CH ₂ -C(CF ₃ ) _{2 -OH, -C(CF 3} ) ₂ -OH at the terminal may be introduced. As described above, a copolymer in which a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is introduced is effective in reducing development defects and LER (line edge roughness: unevenness of line sidewalls).

(A1) The weight average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography (GPC)) of component (A1) is not specifically limited, 1000-50000 are preferable, 2000-30000 are more preferable, 3000- 20000 is more preferable.

If the Mw of the component (A1) is below the preferable upper limit of this range, there is sufficient solubility in a resist solvent for use as a resist. If Mw is more than the preferable lower limit of this range, the dry etching resistance and resist pattern cross-sectional shape are good.

(A1) The dispersion degree (Mw/Mn) of a component is not specifically limited, 1.0-4.0 are preferable, 1.0-3.0 are more preferable, 1.0-2.0 are especially preferable. In addition, Mn represents a number average molecular weight.

・About base components other than component (A1)

In the resist composition of the present embodiment, as component (A), a base component whose solubility in a developer changes due to the action of an acid that does not correspond to component (A1) may be used in combination. The base component that does not fall under the component (A1) is not particularly limited, and can be arbitrarily selected from a number of conventionally known base components for chemically amplified resist compositions, and can include high molecular weight compounds or low molecular weight compounds. It may be used individually by 1 type, and may be used in combination of 2 or more type.

25 mass % or more is preferable with respect to the total mass of (A) component, as for the ratio of (A1) component in (A) component, 50 mass % or more is more preferable, 75 mass % or more is still more preferable, 100 It may be mass %. When the ratio is 25 mass % or more, a resist pattern excellent in various lithographic properties is easily formed.

In the resist composition of the present embodiment, the content of component (A) is preferably 20 mass% or more with respect to the total mass (100 mass%) of the resist composition. When the content of the component (A) is 20 mass% or more, a resist film having a thick film (eg, a film thickness of 5 µm or more) is easily formed. Although the upper limit of content of (A) component will not be specifically limited if it is a density|concentration which can form a resist film, For example, it can be 50 mass % or less. (A) 20-50 mass % is preferable, as for content of component, 22-50 mass % is more preferable, and its 25-50 mass % is still more preferable.

<(Z) component>

(Z) Component is an ionic liquid.

An ionic liquid means a salt which exists as a liquid. An ionic liquid is composed of a cation moiety and an anion moiety, and the electrostatic interaction between these ions is weak and is a salt that is difficult to crystallize. The ionic liquid has a melting point of 100°C or less, and further has the following characteristics 1) to 5).

Characteristics 1) The vapor pressure is very low. Characteristic 2) Incombustibility over a wide temperature range. Characteristic 3) Maintains liquid phase in a wide temperature range. Characteristic 4) The density is greatly changed. Characteristic 5) It is possible to control the polarity.

Moreover, in this embodiment, it is preferable that an ionic liquid is non-polymerizable.

1000 or less are preferable, as for the mass average molecular weight (Mw) of an ionic liquid, 750 or less are more preferable, and 500 or less are still more preferable.

· (Z) cation moiety of component

Although the cation moiety of component (Z) is not particularly limited, it is preferable that the dipole moment of the cation moiety is 3 debye or more, more preferably 3.2 to 15 debye, from the viewpoint that the effect of improving the phase separation performance is more easily obtained, More preferably, it is 3.4-12 debye.

The "dipole moment of a cation part" means a parameter which quantitatively shows the polarity (deflection of electric charge) of a cation part. 1 debye is defined as 1 × 10 ^-18 esu·cm. In this specification, the dipole moment of a cation part represents the simulation value by CAChe. For example, according to CAChe Work System Pro Version 6.1.12.33, it is measured by performing structural optimization using MM geometry (MM2), PM3 geometry.

As a cation whose dipole moment is 3 debye or more, an imidazolium ion, a pyrrolidinium ion, a piperidinium ion, an ammonium ion, a sulfonium ion, a phosphonium ion, etc. are mentioned preferably, for example.

That is, as a preferable component (Z), an imidazolium salt, a pyrrolidinium salt, a piperidinium salt, an ammonium salt, a sulfonium salt, or a phosphonium salt etc. are mentioned, for example. Among these salts, it is preferable that the cation moiety is a cation having a substituent at the point where phase-separation performance improves more easily. Especially, it is preferable that it is a cation containing a C1 or more alkyl group which may have a substituent, or a cation containing a polar group. The alkyl group having 1 or more carbon atoms contained in the above cation preferably has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms. Although the said alkyl group may be a linear alkyl group or a branched alkyl group may be sufficient as it, it is preferable that it is a linear alkyl group. As a substituent which the C2 or more alkyl group may have, a hydroxyl group, a vinyl group, an allyl group, etc. are mentioned. Moreover, it is preferable that the C1 or more alkyl group does not have a substituent. As a polar group which said cation contains, a carboxy group, a hydroxyl group, an amino group, a sulfo group etc. are mentioned, for example.

As a more preferable cation moiety of component (Z), a cation represented by the following general formulas (z-ca-1) to (z-ca-5) is exemplified.

[Formula 47]

[In the formula, Rz ^c1 to Rz ^c6 are each independently an alkyl group having 1 to 12 carbon atoms. Rz ^c7 to Rz ^c9 are each independently an aryl group which may have a substituent. Rz ^c10 to Rz ^c13 are each independently a linear alkyl group having 1 to 20 carbon atoms.]

In the formula (z-ca-1), Rz ^c1 and Rz ^c2 are each independently an alkyl group having 1 to 12 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms, and preferably having 1 carbon atoms. A -12 linear alkyl group is more preferable, and a C1-C6 linear alkyl group is still more preferable. Especially, ^{it is especially preferable that Rz c1} is a methyl group or an ethyl group, and Rz ^c2 is a C1-C4 linear alkyl group.

In the formula (z-ca-2), Rz ^c3 and Rz ^c4 are each independently a C1-C12 alkyl group, preferably a C1-C12 linear or branched alkyl group, and C1 A -12 linear alkyl group is more preferable, and a C1-C6 linear alkyl group is still more preferable. Especially, it is especially preferable that ^{Rz c3} is a methyl group or an ethyl group, and Rz ^{c4 is a C1-C4 linear alkyl group.}

In the formula (z-ca-3), Rz ^c5 and Rz ^c6 are each independently an alkyl group having 1 to 12 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms, preferably having 1 carbon atoms. A -12 linear alkyl group is more preferable, and a C1-C6 linear alkyl group is still more preferable. Especially, ^{it is especially preferable that Rz c5} is a C1-C6 linear alkyl group, and Rz ^c6 is a C1-C4 linear alkyl group.

In the formula (z-ca-4), Rz ^c7 to Rz ^c9 are each independently an aryl group which may have a substituent, preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

As ^{a substituent which the aryl group in Rz c7} to Rz ^c9 may have, for example, an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, the general formula (ca-r-1) and groups each represented by - (ca-r-7).

In the formula (z-ca-5), Rz ^c10 to Rz ^c13 are each independently a linear alkyl group having 1 to 20 carbon atoms, preferably a linear alkyl group having 3 to 18 carbon atoms, and 4 carbon atoms. A -16 linear alkyl group is more preferable, and a C5-C15 linear alkyl group is still more preferable.

· (Z) the anion part of the component

Although the anion part of (Z) component is not specifically limited, The anion etc. which are represented by any of the following general formulas (z-an-1) - (z-an-5) are mentioned.

[Formula 48]

[In formula (z-an-1), Rz ^a1 represents an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain hydrocarbon group which may have a substituent. In the formula (z-an-2), Rz ^a2 represents an alkyl group having 1 to 5 carbon atoms which may be substituted with a fluorine atom. k is an integer of 1-4, l is an integer of 0-3, and it is k+1=4. In formula (z-an-3), Rz ^a3 represents a C1-C5 alkyl group which may be substituted by the fluorine atom. m is an integer of 1-6, n is an integer of 0-5, and m+n=6.]

[Formula 49]

[In the formula (z-an-4), X" represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. In the formula (z-an-5), Y" and Z" are , each independently represents an alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom.]

In the formula (z-an-1), Rz ^a1 represents an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain hydrocarbon group which may have a substituent.

In the formula (z-an-1), when Rz ^a1 is an aromatic hydrocarbon group which may have a substituent, specifically, as an aromatic ring included in R, benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene, etc. an aromatic hydrocarbon ring of ; an aromatic heterocyclic ring in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom; and the like. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specific examples of the aromatic hydrocarbon group include a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring (aryl group); A group in which one of the hydrogen atoms of the aryl group is substituted with an alkylene group (eg, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc. of an arylalkyl group); and the like. It is preferable that carbon number of the said alkylene group (the alkyl chain in an arylalkyl group) is 1-4, It is more preferable that it is 1-2, It is especially preferable that it is 1.

As an aromatic hydrocarbon group for R, a phenyl group or a naphthyl group is preferable, and a phenyl group is more preferable.

In the formula (z-an-1), when Rz ^a1 is an aliphatic cyclic group which may have a substituent, it may be polycyclic or monocyclic. The monocyclic aliphatic cyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 8 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane and cyclooctane. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane is preferably a polycycloalkane having 7 to 12 carbon atoms, specifically adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

Among them, the aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane.

In the formula (z-an-1), ^{the chain hydrocarbon group for Rz a1} is preferably a chain alkyl group. The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically, 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, a decyl group, etc. linear alkyl group; 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-methyl group branched alkyl groups such as pentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group; can be heard The chain alkyl group has more preferably 1 to 6 carbon atoms, and still more preferably 1 to 3 carbon atoms. Moreover, it is preferable that it is a linear alkyl group.

In the formula (z-an-1), ^{as the substituent which the aromatic hydrocarbon group, alicyclic group or chain hydrocarbon group of Rz a1} may have, a hydroxyl group, an alkyl group, a fluorine atom or a fluorinated alkyl group, a triphenylphosphonium group, etc. can be heard

In the formula (z-an-1), Rz ^a1 is preferably a methyl group, a trifluoromethyl group, a p-tolyl group or a propyltriphenylphosphonium group.

In the formula (z-an-2), Rz ^a2 represents an alkyl group having 1 to 5 carbon atoms which may be substituted with a fluorine atom.

k is an integer of 1-4, Preferably it is an integer of 3-4, Most preferably, it is 4.

l is an integer of 0-3, Preferably it is an integer of 0-2, Most preferably, it is 0. When l is 2 or more, a plurality of Rz ^a2 may be the same as or different from each other, but preferably the same as each other.

In the formula (z-an-3), Rz ^a3 represents an alkyl group having 1 to 5 carbon atoms which may be substituted with a fluorine atom.

m is an integer of 1-6, Preferably it is an integer of 3-6, Most preferably, it is 6.

n is an integer of 0-5, Preferably it is an integer of 0-3, Most preferably, it is 0. When n is 2 or more, a plurality of Rz ^a3 may be the same as or different from each other, but preferably the same as each other.

In the formula (z-an-4), X" represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. The alkylene group here may be linear or branched. , has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, and most preferably 3 carbon atoms.

In the formula (z-an-5), Y″ and Z″ each independently represent an alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. The alkyl group here may be linear or branched, and may have 1 to 10 carbon atoms, preferably 1 to 7 carbon atoms, and more preferably 1 to 3 carbon atoms. Among them, in (z-an-5), it is particularly preferable that both Y" and Z" are trifluoromethyl groups.

The carbon number of the alkylene group of X", or the number of carbon atoms of each alkyl group of Y" and Z", within the above-mentioned carbon number range, for reasons such as good solubility in organic solvent components, the smaller it is, the more preferable.

In addition, in the alkylene group of X", or each of the alkyl groups of Y" and Z", it is preferable that the number of hydrogen atoms substituted with fluorine atoms increases due to reasons such as increasing acid strength. The fluorination rate of the ene group or the alkyl group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkylene group or perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms.

As the anion moiety of the component (Z), among the anion moieties represented by any of the formulas (z-an-1) to (z-an-5), the general formulas (z-an-1), (z-an- 2), the anion moiety represented by (z-an-3) or (z-an-5) is preferable.

Among them, as the component (Z), a compound represented by any of the following general formulas (z-1) to (z-5) is preferable.

[Formula 50]

[In the formula, Rz ^c1 to Rz ^c6 are each independently an alkyl group having 1 to 12 carbon atoms. Xz1 ^- to Xz5 ^- are each independently an anion represented by any of the general formulas (z-an-1) to (z-an-5).]

In the formula (z-1) ~ (z -3), it is the same as ^c1 ~ Rz Rz is ^{c6, c1} ~ Rz Rz ^c6 in the formula (z-ca-1) ~ (z-ca-3).

In the formula (z-1), Xz1 ^- is preferably an anion represented by the formula (z-an-5).

In the formula (z-2), Xz2 ^- is preferably an anion represented by the formula (z-an-5).

In the formula (z-3), Xz3 ^- is preferably an anion represented by the formula (z-an-2).

In the formula (z-4), Xz4 ^- is preferably an anion represented by the formula (z-an-5).

In the formula (z-5), Xz5 ^- is preferably an anion represented by the formula (z-an-5).

Although the specific example of compound (IL) is given below, it is not limited to these.

[Formula 51]

[Formula 52]

[Formula 53]

In the resist composition of the present embodiment, the component (Z) may be used alone or in combination of two or more.

In the resist composition of the present embodiment, the content of component (Z) is preferably greater than 0 parts by mass and less than 25 parts by mass, more preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 100 parts by mass of component (A). It is more preferable that it is -15 mass parts, and it is especially preferable that it is 3-12 mass parts.

When the content of the component (Z) is equal to or more than the lower limit of the above range, the sensitivity is more likely to be increased, and the occurrence of cracks during resist pattern formation is easily suppressed. On the other hand, when the content of the component (Z) is below the upper limit of the above range, a resist pattern having a good shape is easily obtained.

<Other ingredients>

The resist composition of the present embodiment may further contain other components in addition to the components (A) and (Z) described above. As other components, (B) component, (D) component, (E) component, (F) component, (S) component etc. which are shown below are mentioned, for example.

≪Acid generator component (B)≫

The resist composition of the present embodiment contains, in addition to component (A) and component (Z), an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as “component (B)”). may contain.

The component (B) is not particularly limited, and those previously proposed as acid generators for chemically amplified resist compositions can be used.

As such an acid generator, Onium salt-type acid generators, such as an iodonium salt and a sulfonium salt, an oxime sulfonate-type acid generator; diazomethane-based acid generators such as bisalkyl or bisarylsulfonyldiazomethanes and poly(bissulfonyl)diazomethanes; and various kinds of nitrobenzylsulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

As (B) component, it is preferable to contain the compound (B1) (henceforth "(B1) component") which consists of an onium salt.

・(B1) About component

As the component (B1), for example, a compound represented by the following general formula (b-1) (hereinafter also referred to as “component (b-1)”), a compound represented by the general formula (b-2) (hereinafter referred to as “component (b-1)”) (b-2) also referred to as "component") or a compound represented by the general formula (b-3) (hereinafter also referred to as "component (b-3)").

[Formula 54]

[wherein, R ¹⁰¹ and R ¹⁰⁴ to R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring structure. R ¹⁰² is a C1-C5 fluorinated alkyl group or a fluorine atom. Y ¹⁰¹ is a divalent linking group or a single bond containing an oxygen atom. V ¹⁰¹ to V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group. L ¹⁰¹ to L ¹⁰² are each independently a single bond or an oxygen atom. L ¹⁰³ to L ¹⁰⁵ are each independently a single bond, -CO-, or -SO ₂ -. m is an integer greater than or equal to 1, and M' ^m+ is an m-valent onium cation.]

｛Anion part｝

- (b-1) anion in component

In formula (b-1), R ¹⁰¹ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

Cyclic group which may have a substituent:

The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group which does not have aromaticity. Moreover, saturated or unsaturated may be sufficient as an aliphatic hydrocarbon group, and it is preferable that it is usually saturated.

The aromatic hydrocarbon group for R ¹⁰¹ is a hydrocarbon group having an aromatic ring. It is preferable that carbon number of this aromatic hydrocarbon group is 3-30, It is more preferable that it is 5-30, 5-20 are still more preferable, 6-15 are especially preferable, and 6-10 are the most preferable. However, carbon number in a substituent shall not be included in the carbon number.

Specifically, the aromatic ring of the aromatic hydrocarbon group for R ¹⁰¹ is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic ring in which some of the carbon atoms constituting these aromatic rings are substituted with hetero atoms. and the like. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specifically, the aromatic hydrocarbon group for R ¹⁰¹ is a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), and one hydrogen atom in the aromatic ring is alkylene. and a group substituted with a group (eg, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group). It is preferable that carbon number of the said alkylene group (alkyl chain in an arylalkyl group) is 1-4, It is more preferable that it is 1-2, It is especially preferable that it is 1.

^Examples of the cyclic aliphatic hydrocarbon group for R 101 include an aliphatic hydrocarbon group having a ring in its structure.

Examples of the aliphatic hydrocarbon group containing a ring in this structure include an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group , a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.

It is preferable that carbon number is 3-20, and, as for the said alicyclic hydrocarbon group, it is more preferable that it is 3-12.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include 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 preferably has 7 to 30 carbon atoms. Among them, examples of the polycycloalkane include polycycloalkanes having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane; A polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton is more preferable.

Among them, ^{the cyclic aliphatic hydrocarbon group for R 101} is preferably a group in which one or more hydrogen atoms are removed from monocycloalkane or polycycloalkane, more preferably a group in which one hydrogen atom is removed from polycycloalkane, An adamantyl group and a norbornyl group are especially preferable, and an adamantyl group is most preferable.

It is preferable that carbon number is 1-10, as for the linear aliphatic hydrocarbon group which may couple|bond with an alicyclic hydrocarbon group, 1-6 are more preferable, 1-4 are still more preferable, and 1-3 are the most preferable. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and 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.

The branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched chain aliphatic hydrocarbon group is preferably a branched chain alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkylmethylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{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 -, -C(CH ₂ CH _{3) 2} -CH ₂ - alkyl group such as ethylene; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -, etc. are mentioned.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

Moreover, ^{the cyclic hydrocarbon group for R 101} may contain a hetero atom like a heterocyclic ring. Specifically, the lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), and the general formulas (a5-r-1) to (a5-r-4), respectively -SO ₂ - containing cyclic groups shown, and heterocyclic groups each represented by the following formulas (r-hr-1) to (r-hr-16) are exemplified.

[Formula 55]

Examples of the substituent in the cyclic group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.

The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group or tert-butoxy group, and a methoxy group , an ethoxy group is most preferred.

As a halogen atom as a substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include an alkyl group having 1 to 5 carbon atoms, for example, a group in which some or all of the hydrogen atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are substituted with the above halogen atoms. have.

The carbonyl group as a substituent is a group that substitutes for the methylene group (-CH ₂ -) constituting the cyclic hydrocarbon group.

A chain alkyl group which may have a substituent:

The linear alkyl group for R ¹⁰¹ may be either linear or branched.

As a linear alkyl group, it is preferable that carbon number is 1-20, It is more preferable that it is 1-15, and 1-10 are the most preferable. Specifically, for example, 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, a decanyl group, an undecyl group, a dodecyl group, a tridecyl group, an isotridecyl group , tetradecyl group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group, etc. are mentioned.

As a branched alkyl group, it is preferable that carbon number is 3-20, It is more preferable that it is 3-15, 3-10 are the most preferable. 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, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, etc. are mentioned.

A chain alkenyl group which may have a substituent:

The chain alkenyl group for R ¹⁰¹ may be either linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5, still more preferably 2 to 4, 3 is particularly preferred. As a linear alkenyl group, a vinyl group, a propenyl group (allyl group), a butynyl group etc. are mentioned, for example. As a branched alkenyl group, 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group etc. are mentioned, for example.

As the chain alkenyl group, among the above, a linear alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain alkyl or alkenyl group for R ¹⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and a cyclic group for ^{R 101 .} can

Among the above, R ¹⁰¹ is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, a group in which one or more hydrogen atoms are removed from a phenyl group, a naphthyl group or a polycycloalkane; lactone-containing cyclic groups each represented by the general formulas (a2-r-1) to (a2-r-7); _{-SO 2} - containing cyclic groups each represented by the above general formulas (a5-r-1) to (a5-r-4) are preferable.

In formula (b-1), Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom.

When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, Y ¹⁰¹ may contain atoms other than an oxygen atom. As atoms other than an oxygen atom, a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom, etc. are mentioned, for example.

Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxycarbonyl group (-OC(=O)-) ), amide bond (-C(=O)-NH-), carbonyl group (-C(=O)-), carbonate bond (-OC(=O)-O-), non-hydrocarbon oxygen atom-containing linking groups ; The combination of the non-hydrocarbon type oxygen atom containing coupling group and an alkylene group, etc. are mentioned. A sulfonyl group (-SO ₂ -) may be further linked to this combination. Examples of the divalent linking group containing such an oxygen atom include linking groups represented by the following general formulas (y-al-1) to (y-al-7).

[Formula 56]

[Wherein, V' ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]

V 'group is a divalent saturated hydrocarbon group of the ^102, preferably an alkylene group of 1 to 30 carbon atoms, more preferably an alkylene group of 1 to 10 carbon atoms, more preferably an alkylene group of 1 to 5 carbon atoms.

The alkylene group for V' ¹⁰¹ and V' ¹⁰² may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferable.

Specifically as the alkylene group for V' ¹⁰¹ and V' ¹⁰² _{, 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 Alkylmethylene groups, such as CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{2 -;} ethylene group [-CH ₂ CH 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 -} ; trimethylene group (n-propylene group) [-CH ₂ CH ₂ CH ₂ -] ; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} tetramethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ -] ; alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -;} and a pentamethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -].

In addition, or may V 'or ¹⁰¹ V' ¹⁰² portion of the methylene groups in the alkylene groups of the, optionally substituted by a divalent aliphatic cyclic group with a carbon number of 5-10. The aliphatic cyclic group is a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group ^{) of Ra' 3 in} the above formula (a1-r-1) except for one more hydrogen atom. A divalent group is preferable, and a cyclohexylene group, a 1, 5- adamantylene group, or a 2, 6- adamantylene group is more preferable.

As Y ¹⁰¹ , a divalent linking group containing an ester bond or a divalent linking group containing an ether bond is preferable, and a linking group each represented by the above formulas (y-al-1) to (y-al-5) is more preferable. Do.

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and the fluorinated alkylene group for V ^{101 preferably have 1 to 4 carbon atoms.} A fluorinated alkylene group in the V ¹⁰¹ is, a part or all of the hydrogen atoms of the alkylene group of the ¹⁰¹ V may be substituted with a fluorine atom. Among them, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b-1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. It is preferable that it is a fluorine atom or a C1-C5 perfluoroalkyl group, and, as for R ^{102, it is more preferable that it is a fluorine atom.}

As a specific example of the anion moiety represented by the formula (b-1), for example, when Y ¹⁰¹ is a single bond, fluorination of trifluoromethanesulfonate anion, perfluorobutanesulfonate anion, etc. an alkylsulfonate anion; When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, an anion represented by any of the following formulas (an-1) to (an-3) is exemplified.

[Formula 57]

[wherein, R" ¹⁰¹ is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group each represented by the above formulas (r-hr-1) to (r-hr-6), or a substituent R" ¹⁰² is an aliphatic cyclic group which may have a substituent, each represented by the above general formulas (a2-r-1) and (a2-r-3) to (a2-r-7). _{a lactone-containing cyclic group, or a -SO 2} -containing cyclic group each represented by the general formulas (a5-r-1) to (a5-r-4). R" ¹⁰³ is an optionally substituted aromatic cyclic group, an optionally substituted aliphatic cyclic group, or an optionally substituted chain alkenyl group. V" ¹⁰¹ is a single bond, an alkyl having 1 to 4 carbon atoms. a lene group or a fluorinated alkylene group having 1 to 4 carbon atoms. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. v" is each independently an integer from 0 to 3, q" is each independently an integer from 0 to 20, and n" is 0 or 1.]

The aliphatic cyclic group which may have a substituent for R" ¹⁰¹ , R" ¹⁰² and R" ¹⁰³ is preferably the group exemplified as the cyclic aliphatic hydrocarbon group for ^{R 101 in the above formula (b-1).} Examples of the substituent include the same substituents as the substituents which may substitute the cyclic aliphatic hydrocarbon group for ^{R 101 in the formula (b-1).}

The aromatic cyclic group which may have a substituent in R" ¹⁰³ is preferably the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group ^{in R 101 in the formula (b-1).} The same thing as the substituent which may substitute the aromatic hydrocarbon group ^{in R<101>} in said Formula (b-1) is mentioned.

The chain alkyl group which may have a substituent for R" ¹⁰¹ is preferably the group exemplified as the chain alkyl group for ^{R 101 in the formula (b-1).}

The chain alkenyl group which may have a substituent for R″ ¹⁰³ is preferably the group exemplified as the chain alkenyl group for ^{R 101 in the formula (b-1).}

- (b-2) anion in component

In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, ^{The same thing as R 101} in Formula (b-1) is mentioned, respectively. However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.

R ¹⁰⁴ and R ¹⁰⁵ are preferably a linear alkyl group which may have a substituent, and more preferably a linear or branched alkyl group, or a linear or branched fluorinated alkyl group.

The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and still more preferably 1 to 3 carbon atoms. The carbon number of the chain alkyl group of R ¹⁰⁴ , R ¹⁰⁵ is preferably smaller within the above carbon number range for reasons such as good solubility in the resist solvent. In addition, in ^{the chain alkyl group of R 104} , R ^{105 ,} the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and the transparency to high-energy light or electron beams of 250 nm or less is improved. It is preferable because The proportion of fluorine atoms in the chain alkyl group, that is, the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%, and most preferably, a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms. to be.

In formula (b-2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and the same as ^{V 101 in formula (b-1) can be mentioned.}

In formula (b-2), L ¹⁰¹ and L ¹⁰² are each independently a single bond or an oxygen atom.

- (b-3) anion in component

In formula (b-3), R ¹⁰⁶ to R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, ^{The same thing as R 101} in Formula (b-1) is mentioned, respectively.

In formula (b-3), L ¹⁰³ to L ¹⁰⁵ each independently represent a single bond, -CO-, or -SO ₂ -.

Among the above, as an anion part of (B) component, the anion in (b-1) component is preferable. Among these, a fluorinated alkylsulfonate anion or an anion represented by any of the general formulas (an-1) to (an-3) is more preferable, and a fluorinated alkylsulfonate anion or a general formula (an-1) ) and an anion represented by any of (an-2) is more preferable.

｛Cathion Division｝

In said Formula (b-1), Formula (b-2), and Formula (b-3), M' ^m+ represents an onium cation of m valence. Among these, sulfonium cation and iodonium cation are preferable. m is an integer of 1 or more.

As a preferable cation moiety ((M' ^{m +} ) _1/m ), organic cations respectively represented by the following general formulas (ca-1) to (ca-4) are exemplified.

[Formula 58]

[In the formula, R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² each independently represent an optionally substituted aryl group, an alkyl group, or an alkenyl group. R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or -SO ₂ - containing cyclic group which may have a substituent. L ²⁰¹ represents -C(=O)- or -C(=O)-O-. Y ²⁰¹ each independently represents an arylene group, an alkylene group, or an alkenylene group. x is 1 or 2. W ²⁰¹ represents a (x+1) valent linking group.]

^{Examples of the aryl group for R 201} to R ²⁰⁷ and R ²¹¹ to R ²¹² in the general formulas (ca-1) to (ca-4) include an unsubstituted aryl group having 6 to 20 carbon atoms, A phenyl group and a naphthyl group are preferable.

The alkyl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.

The ^{alkenyl group for R 201} to R ²⁰⁷ and R ²¹¹ to R ²¹² preferably has 2 to 10 carbon atoms.

Examples of the substituent which R ²⁰¹ to R ²⁰⁷ , and R ²¹⁰ to R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and the following general formula (ca-r -1) and groups each represented by (ca-r-7) are exemplified.

[Formula 59]

[ ^{Wherein, R'201} is each independently a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.]

Cyclic group which may have a substituent:

The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group which does not have aromaticity. Moreover, saturated or unsaturated may be sufficient as an aliphatic hydrocarbon group, and it is preferable that it is usually saturated.

The aromatic hydrocarbon group for R' ²⁰¹ is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. . However, carbon number in a substituent shall not be included in the carbon number.

Specifically, as the aromatic ring of the aromatic hydrocarbon group for R' ²⁰¹ , benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic group in which a part of carbon atoms constituting these aromatic rings is substituted with a hetero atom. rings, and the like. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specifically, as the aromatic hydrocarbon group for R' ²⁰¹ , a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), and one hydrogen atom in the aromatic ring is alkylene and a group substituted with a group (eg, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group). It is preferable that carbon number of the said alkylene group (the alkyl chain in an arylalkyl group) is 1-4, C1-C2 is more preferable, C1 is especially preferable.

^Examples of the cyclic aliphatic hydrocarbon group for R' 201 include an aliphatic hydrocarbon group having a ring in its structure.

Examples of the aliphatic hydrocarbon group containing a ring in this structure include an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group , a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.

It is preferable that carbon number is 3-20, and, as for the said alicyclic hydrocarbon group, it is more preferable that it is 3-12.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably a monocycloalkane having 3 to 6 carbon atoms, and specific examples thereof include 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 a polycycloalkane having 7 to 30 carbon atoms. Among them, examples of the polycycloalkane include polycycloalkanes having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane; A polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton is more preferable.

Among these, aliphatic hydrocarbon groups of annular in R ^'201 is the mono cycloalkane or polycycloolefin preferably other than one or more of the hydrogen atom from the alkane group, and polycycloolefin, and a hydrogen atom from the alkane, more preferably groups except one , an adamantyl group or a norbornyl group is particularly preferred, and an adamantyl group is most preferred.

The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and still more preferably has 1 carbon atom. to 3 are particularly preferred.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and 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.

The branched chain aliphatic hydrocarbon group is preferably a branched chain alkylene group, specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkylmethylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) _{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 -, -C(CH ₂ CH _{3) 2} -CH ₂ - alkyl group such as ethylene; Alkyltrimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as alkyltetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -, etc. are mentioned.} As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

The hydrocarbon group is cyclic in R ^'201, may include a hetero atom such as a heterocyclic ring. Specifically, the lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), and the general formulas (a5-r-1) to (a5-r-4), respectively -SO ₂ - containing cyclic group shown, and the heterocyclic group respectively represented by the above formulas (r-hr-1) to (r-hr-16) are mentioned.

Examples of the substituent in the cyclic group of R' ²⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group.

As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.

The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group or tert-butoxy group, and a methoxy group , an ethoxy group is most preferred.

As a halogen atom as a substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include an alkyl group having 1 to 5 carbon atoms, for example, a group in which part or all of the hydrogen atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are substituted with the above halogen atoms. have.

The carbonyl group as a substituent is a group that substitutes for the methylene group (-CH ₂ -) constituting the cyclic hydrocarbon group.

A chain alkyl group which may have a substituent:

The linear alkyl group for R' ²⁰¹ may be either linear or branched.

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, 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, a decanyl group, an undecyl group, a dodecyl group, a tridecyl group, an isotridecyl group , tetradecyl group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group, etc. are mentioned.

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, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, etc. are mentioned.

A chain alkenyl group which may have a substituent:

The chain alkenyl group for R' ²⁰¹ may be either linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, further preferably having 2 to 4 carbon atoms. preferred, particularly preferably having 3 carbon atoms. As a linear alkenyl group, a vinyl group, a propenyl group (allyl group), a butynyl group etc. are mentioned, for example. As a branched alkenyl group, 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group etc. are mentioned, for example.

As the chain alkenyl group, among the above, a linear alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain alkyl or alkenyl group for R' ²⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, ^{a cyclic group for R' 201} , and the like. can be heard

The cyclic group which may have a substituent for R' ²⁰¹ , the chain alkyl group which may have a substituent, or the chain alkenyl group which may have a substituent are other than those described above, a cyclic group or a substituent which may have a substituent. Examples of the chain alkyl group which may have include the same as the acid dissociable group represented by the above-mentioned formula (a1-r-2).

Among them, R' ²⁰¹ is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, for example, a group in which one or more hydrogen atoms are removed from a phenyl group, a naphthyl group, or a polycycloalkane; lactone-containing cyclic groups each represented by the general formulas (a2-r-1) to (a2-r-7); _{-SO 2} - containing cyclic groups each represented by the above general formulas (a5-r-1) to (a5-r-4) are preferable.

In the above general formulas (ca-1) to (ca-4), R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² are bonded to each other to form a ring together with the sulfur atom in the formula. , a sulfur atom, an oxygen atom, a hetero atom such as a nitrogen atom, a carbonyl group, -SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N(R _N )- (the R _N is a C1-C5 alkyl group.) You may couple|bond through functional groups, such as. As a ring to be formed, it is preferable that one ring containing a sulfur atom in the ring skeleton in a formula is a 3-10 membered ring including a sulfur atom, and it is especially preferable that it is a 5-7 membered ring. Specific examples of the formed ring include, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, phenoxati A phosphorus ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring, etc. are mentioned.

R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when they become an alkyl group, they may combine with each other to form a ring.

R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or -SO ₂ - containing cyclic group which may have a substituent.

Examples of the aryl group for R ²¹⁰ include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.

The alkyl group for R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.

The ^{alkenyl group for R 210} preferably has 2 to 10 carbon atoms. As _{the -SO 2} - containing cyclic group which may have a substituent in ^{R 210} _{, "-SO 2} - containing polycyclic group" is preferable, and the group represented by the general formula (a5-r-1) is more preferable. Do.

Y ²⁰¹ each independently represents an arylene group, an alkylene group, or an alkenylene group.

Examples of the arylene group for Y ²⁰¹ include groups in which one hydrogen atom is removed from the aryl group exemplified as the aromatic hydrocarbon group for ^{R 101} in the above formula (b-1).

Examples of the alkylene group and the alkenylene group for Y ²⁰¹ include groups excluding one hydrogen atom from the groups exemplified as the chain alkyl group and chain alkenyl group for ^{R 101 in the above formula (b-1).} can

In the formula (ca-4), x is 1 or 2.

W ²⁰¹ is a (x+1) valent, that is, a divalent or trivalent linking group.

As the ^{divalent linking group for W 201} , a divalent hydrocarbon group which may have a substituent is preferable, and examples of the same divalent hydrocarbon group which may have a substituent as for ^{Ya 21 in the above-mentioned general formula (a2-1) are exemplified.} can The ^{divalent linking group for W 201} may be linear, branched or cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group is preferable. As an arylene group, a phenylene group, a naphthylene group, etc. are mentioned, A phenylene group is especially preferable.

Connection of the trivalent group is ²⁰¹ W, and ²⁰¹ W the group of hydrogen atom from the divalent linking group of 1 except in, in addition to the divalent linking group, and the like which combines the divalent connecting group. The ^{trivalent linking group for W 201} is preferably a group in which two carbonyl groups are bonded to an arylene group.

Specific examples of preferred cations represented by the formula (ca-1) include cations represented by the following formulas (ca-1-1) to (ca-1-70).

[Formula 60]

[Formula 61]

[Formula 62]

[Wherein, g1, g2, and g3 represent the number of repetitions, g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20.]

[Formula 63]

[Formula 64]

[Formula 65]

[In the formula, R ^"201 is the same as with a hydrogen atom or a substituent, and the substituents are all as a substituent which may have the R ²⁰¹ ~ R ^207, and R ²¹⁰ ~ R ²¹² has.]

Specific examples of preferable cations represented by the formula (ca-2) include diphenyliodonium cation and bis(4-tert-butylphenyl)iodonium cation.

Specific examples of preferred cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

[Formula 66]

Specific examples of preferred cations represented by the formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

[Formula 67]

Among the above, as for the cation moiety ((M' ^m+ ) _1/m ), a cation represented by the general formula (ca-1) is preferable. From the viewpoint of maintaining transparency in the thick resist film, in general formula (ca-1), ^{at least one of R 202} to R ²⁰³ is preferably an alkyl group or an alkenyl group, and at least two of R ²⁰² to R ²⁰³ more preferably an alkyl group or alkenyl group Al, more preferably of at least two of R ²⁰² ~ R ²⁰³ is an alkyl group. When ^{two or more of R 202} to R ²⁰³ are an alkyl group or an alkenyl group, the two may be bonded to each other to form a ring together with the sulfur atom in the formula. The cation represented by the general formula (ca-1) is preferably a cation represented by any of the formulas (ca-1-55) to (ca-1-68), and the formula (ca-1-63) A cation represented by any one of to (ca-1-68) is more preferable.

Among these, as the component (B1), a compound represented by the following general formula (b1-1) is particularly preferable.

[Formula 68]

[In the formula, Rb ²⁰¹ is an aryl group which may have a substituent. Rb ²⁰² and Rb ²⁰³ are each independently an alkyl group which may have a substituent or an alkenyl group which may have a substituent. Rb ²⁰² and Rb ²⁰³ may combine with each other to form a ring together with the sulfur atom in the formula. R ¹⁰¹ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. R ¹⁰² is a C1-C5 fluorinated alkyl group or a fluorine atom. Y ¹⁰¹ is a divalent linking group or a single bond containing an oxygen atom. V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group.]

The formula (b1-1) wherein the aryl group which may have a substituent Rb in ^201, is the same aryl group which may have a substituent in R ²⁰¹ in the formula (ca-1). Especially, as Rb ²⁰¹ , a phenyl group or a naphthyl group is preferable, and a phenyl group is more preferable.

In the formula (b1-1), the optionally substituted alkyl group or the optionally substituted alkenyl group in ^{Rb 202} and Rb ^{203 is a substituent in R 202} and R ²⁰³ in the formula (ca-1). It is the same as the alkyl group which may have or the alkenyl group which may have a substituent. Among them, Rb ²⁰² and Rb ²⁰³ are preferably a linear alkyl group having 1 to 5 carbon atoms, and Rb ²⁰² and Rb ²⁰³ are bonded to each other to form a 5-membered ring or a 6-membered ring together with the sulfur atom in the formula It is more preferable to have

In the formula ^{(b1-1), R 101, R} 102, Y 101 and V ¹⁰¹ are the same as R ^101, R ^102, Y ^101, and ¹⁰¹ V in the above formula (b-1).

・(B2) About component

The component (B) may contain an acid generator component (hereinafter referred to as "component (B2)") which does not correspond to the component (B1). The component (B2) is not particularly limited as long as it generates an acid upon exposure and does not fall under the component (B1) described above, and can be arbitrarily selected from known components. (B2) As a component, For example, an oxime sulfonate type acid generator; diazomethane-based acid generators such as bisalkyl or bisarylsulfonyldiazomethanes and poly(bissulfonyl)diazomethanes; and various kinds of nitrobenzylsulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

In the resist composition of the present embodiment, the component (B) may be used alone or in combination of two or more.

When the resist composition contains component (B), the content of component (B) in the resist composition is preferably less than 50 parts by mass, more preferably 0.1 to 40 parts by mass, based on 100 parts by mass of component (A). , 0.3-25 mass parts is more preferable.

(B) By making content of a component into said preferable range, pattern formation is fully performed. Moreover, when each component of a resist composition is dissolved in the organic solvent, since it is easy to obtain a uniform solution and the storage stability as a resist composition becomes favorable, it is preferable.

≪Base component (D)≫

The resist composition of the present embodiment contains, in addition to component (A) and component (Z), a base component (component (D)) that traps (ie, controls diffusion of acid) an acid generated by exposure. may contain. Component (D) acts as an agent (acid diffusion controlling agent) that traps acids generated by exposure in the resist composition.

As the component (D), for example, the photodegradable base (D1) (hereinafter referred to as “component (D1)”), which decomposes upon exposure and loses acid diffusion controllability (hereinafter referred to as “component (D1)”), does not correspond to the component (D1). and nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") etc. are mentioned. Among these, the nitrogen-containing organic compound (D2) (component (D2)) is preferable from the viewpoint of maintaining the sensitivity in the thick resist film. Among the components (D2), chain alkylamines are more preferable from the viewpoint of maintaining transparency in the thick resist film.

・(D1) About component

By using the resist composition containing the component (D1), the contrast between the exposed portion and the unexposed portion of the resist film can be further improved when the resist pattern is formed. The component (D1) is not particularly limited as long as it decomposes upon exposure to lose acid diffusion controllability, and a compound represented by the following general formula (d1-1) (hereinafter referred to as “component (d1-1)”); A compound represented by the following general formula (d1-2) (hereinafter referred to as “component (d1-2)”) and a compound represented by the following general formula (d1-3) (hereinafter referred to as “component (d1-3)”). ) at least one compound selected from the group consisting of

Components (d1-1) to (d1-3) do not act as a target in the exposed part of the resist film because they decompose and lose acid diffusion controllability (basicity), but as a target in the unexposed part of the resist film. works

[Formula 69]

[Wherein, Rd ¹ to Rd ⁴ are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. In this formula (d1-2) of the of Rd ^2, carbon atoms, the fluorine atom adjacent to the S atom is not to be bonded. Yd ¹ is a single bond or a divalent linking group. m is an integer greater than or equal to 1, and M ^m+ is each independently an organic cation having a valence of m.]

｛(d1-1) component ｝

・・Anion part

In formula (d1-1), Rd ¹ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each is the same as ^{R' 201} thing can be heard

Among these, as Rd ¹ , an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkyl group which may have a substituent is preferable. Examples of the substituent which these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, and a lactone-containing cyclic group each represented by the general formulas (a2-r-1) to (a2-r-7). , an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is included as a substituent, an alkylene group may be interposed, and as a substituent in this case, the linking group respectively represented by said formula (y-al-1) - (y-al-5) is preferable. Do.

Preferred examples of the aromatic hydrocarbon group include a polycyclic structure including a phenyl group, a naphthyl group and a bicyclooctane skeleton (a polycyclic structure comprising a bicyclooctane skeleton and a ring structure other than this).

The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane.

The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically, 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, a decyl group, etc. A linear alkyl group of ; 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-methyl group Branched alkyl groups, such as a pentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group, are mentioned.

When the above-mentioned chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 4 carbon atoms. The fluorinated alkyl group may contain atoms other than a fluorine atom. As atoms other than a fluorine atom, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned, for example.

Rd ¹ is preferably a fluorinated alkyl group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms, and a fluorinated alkyl group in which all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms (a linear perfluoroalkyl group) is particularly preferable.

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

[Formula 70]

・・Cathion part

In formula (d1-1), M ^m+ is an m-valent organic cation.

Examples of the organic cation of M ^m+ include preferably the same cations as those represented by the general formulas (ca-1) to (ca-4), and the cation represented by the general formula (ca-1) is More preferably, the cations respectively represented by the formulas (ca-1-1) to (ca-1-70) are still more preferable.

(d1-1) A component may be used individually by 1 type, and may be used in combination of 2 or more type.

｛(d1-2) component｝

・・Anion part

In formula (d1-2), Rd ² is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and is the same as ^{R' 201} can be heard

However, in Rd ² , a fluorine atom is not bonded to a carbon atom adjacent to the S atom (not substituted with fluorine). Thereby, the anion of (d1-2) component turns into a suitable weak acid anion, and the quenching ability as (D)component improves.

Rd ² is preferably a chain alkyl group which may have a substituent or an aliphatic cyclic group which may have a substituent. As a chain|strand-type alkyl group, it is preferable that it is C1-C10, and it is more preferable that it is 3-10. Examples of the aliphatic cyclic group include a group (which may have a substituent) in which one or more hydrogen atoms are removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like; It is more preferable that it is a group obtained by removing one or more hydrogen atoms from camphor or the like.

The hydrocarbon group of Rd ² may have a substituent, and as the substituent, the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in ^{Rd 1 of the above formula (d1-1) may have} The same thing as a substituent is mentioned.

Preferred specific examples of the anion moiety of the component (d1-2) are shown below.

[Formula 71]

・・Cathion part

In formula (d1-2), M ^m+ is an organic cation of m valence, and is the same as ^{M m+ in said formula (d1-1).}

(d1-2) A component may be used individually by 1 type, and may be used in combination of 2 or more type.

｛(d1-3) component｝

・・Anion part

In the formula (d1-3), Rd ³ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and includes the same as ^{R' 201 above.} and a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group is preferable. Especially, a fluorinated alkyl group is preferable, and the thing similar to the ^{said fluorinated alkyl group of said Rd 1 is more preferable.}

In formula (d1-3), Rd ⁴ is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and is the same as ^{R' 201} can be heard

Especially, it is preferable that they are an alkyl group which may have a substituent, an alkoxy group, an alkenyl group, and a cyclic group.

The alkyl group for Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. are mentioned. A part of the hydrogen atoms of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group, or the like.

The alkoxy group for Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specifically as an alkoxy group having 1 to 5 carbon atoms, a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group, n- butoxy group and tert-butoxy group. Especially, a methoxy group and an ethoxy group are preferable.

Examples of the alkenyl group for Rd ^{4 include the same groups as the alkenyl group for R' 201} , and a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferable. These groups may further have a C1-C5 alkyl group or a C1-C5 halogenated alkyl group as a substituent.

Examples of the cyclic group for Rd ^{4 include the same groups as the cyclic group for R' 201} , cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclo. An alicyclic group in which one or more hydrogen atoms have been removed from a cycloalkane such as decane, or an aromatic group such as a phenyl group or a naphthyl group is preferable. When Rd ⁴ is an alicyclic group, the resist composition dissolves favorably in the organic solvent, thereby improving the lithographic properties. In addition, when Rd ⁴ 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 has good sensitivity and lithographic characteristics.

In formula (d1-3), Yd ¹ is a single bond or a divalent linking group.

Although it does not specifically limit as a divalent linking group in Yd ¹ , A divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, a divalent linking group containing a hetero atom, etc. are mentioned. Examples of these are the same as the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom, which are mentioned in the description of the divalent linking group for ^{Ya 21 in the formula (a2-1), respectively.}

Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. As an alkylene group, it is more preferable that it is a linear or branched alkylene group, and it is still more preferable that it is a methylene group or an ethylene group.

Preferred specific examples of the anion moiety of the component (d1-3) are shown below.

[Formula 72]

[Formula 73]

・・Cathion part

In formula (d1-3), M ^m+ is an organic cation of m valence, and is the same as ^{M m+ in said formula (d1-1).}

(d1-3) A component may be used individually by 1 type, and may be used in combination of 2 or more type.

(D1) component may use only 1 type of the said (d1-1)-(d1-3) component, and may use it in combination of 2 or more type.

When the resist composition contains component (D1), the content of component (D1) in the resist composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, based on 100 parts by mass of component (A), , 5-10 mass parts is more preferable.

When the content of the component (D1) is equal to or more than the preferred lower limit, particularly favorable lithography characteristics and resist pattern shape can be easily obtained. On the other hand, if it is below an upper limit, a sensitivity can be maintained favorably and it is excellent also in a throughput.

(D1) Method of Preparation of Component:

The manufacturing method of said (d1-1) component and (d1-2) component is not specifically limited, It can manufacture by a well-known method.

Moreover, the manufacturing method of (d1-3) component is not specifically limited, For example, it carries out similarly to the method of US2012-0149916, and manufactures.

・(D2) About component

As (D)component, it is preferable to contain the nitrogen-containing organic compound component (henceforth "(D2) component") which does not correspond to said (D1) component.).

The component (D2) is not particularly limited as long as it acts as an acid diffusion controlling agent and does not fall under the component (D1), and any known component may be used arbitrarily. Especially, an aliphatic amine is preferable, and especially a secondary aliphatic amine and a tertiary aliphatic amine are more preferable especially among these.

The aliphatic amine is an amine having at least one aliphatic group, and the aliphatic group preferably has 1 to 12 carbon atoms.

Examples of the aliphatic amine include amines (alkylamines or alkylalcoholamines) or cyclic amines in which at least one hydrogen atom of _{ammonia NH 3 is substituted with an alkyl group having 12 or less carbon atoms or a hydroxyalkyl group.}

Specific examples of the alkylamine and the alkyl alcoholamine include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; Trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri trialkylamines such as -n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkyl alcoholamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine and tri-n-octanolamine. Among these, a C5-C10 trialkylamine is more preferable, and tri-n-pentylamine or tri-n-octylamine is especially preferable.

As a cyclic amine, the heterocyclic compound which contains a nitrogen atom as a hetero atom is mentioned, for example. The heterocyclic compound may be a monocyclic compound (aliphatic monocyclic amine) or a polycyclic compound (aliphatic polycyclic amine).

Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and 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, etc. are mentioned.

Examples of other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, and 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-hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, etc. are mentioned, and triethanolamine triacetate is preferable.

Moreover, as (D2) component, you may use an aromatic amine.

Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and the like. can be heard

As the component (D2), from the viewpoint of maintaining transparency in the thick film resist, an aliphatic amine is preferable, a chain aliphatic amine is more preferable, and a chain alkylamine is still more preferable. The chain alkyl group of the chain alkylamine preferably has 5 to 10 carbon atoms. Especially, the dialkylamine or trialkylamine which has a C5-C10 linear alkyl group is preferable, and a trialkylamine is more preferable.

(D2) A component may be used individually by 1 type, and may be used in combination of 2 or more type. When the resist composition contains the component (D2), the content of the component (D2) in the resist composition is usually used in the range of 0.005 to 5 parts by mass based on 100 parts by mass of the component (A). By setting it as the said range, a resist pattern shape, stability with time after exposure, etc. improve.

«At least one compound (E) selected from the group consisting of organic carboxylic acids and phosphorus oxo acids and derivatives thereof»

In the resist composition of the present embodiment, for the purpose of preventing sensitivity deterioration, improving resist pattern shape, stability over time after exposure, etc., as optional components, an organic carboxylic acid, phosphorus oxo acid, and derivatives thereof At least one compound (E) selected from the group (hereinafter referred to as “component (E)”) can be contained.

As organic carboxylic acid, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, etc. are preferable, for example.

Phosphoric acid, phosphonic acid, phosphinic acid etc. are mentioned as an oxo acid of phosphorus, Among these, phosphonic acid is especially preferable.

Examples of the derivative of phosphorus oxo acid include esters in which a hydrogen atom of the oxo acid is substituted with a hydrocarbon group. Examples of the hydrocarbon group include an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 15 carbon atoms, and the like. can be heard

Phosphoric acid esters, such as phosphoric acid di-n-butyl ester and phosphoric acid diphenyl ester, etc. are mentioned as a derivative|guide_body of phosphoric acid.

Examples of the derivative of phosphonic acid include phosphonic acid esters such as dimethyl phosphonic acid, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.

As a derivative of a phosphinic acid, a phosphinic acid ester, phenylphosphinic acid, etc. are mentioned.

In the resist composition of this embodiment, the component (E) may be used individually by 1 type, and may use 2 or more types together.

When the resist composition contains component (E), the content of component (E) is usually used in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of component (A).

≪Fluorine additive component (F)≫

The resist composition of the present embodiment may contain a fluorine additive component (hereinafter referred to as "component (F)") in order to impart water repellency to the resist film or to improve lithography characteristics.

(F) As a component, Unexamined-Japanese-Patent No. 2010-002870, Unexamined-Japanese-Patent No. 2010-032994, Unexamined-Japanese-Patent No. 2010-277043, Unexamined-Japanese-Patent No. 2011-13569, Unexamined-Japanese-Patent No. The fluorinated polymer compound described in Publication No. 2011-128226 can be used.

(F) The polymer which has a structural unit (f1) represented by the following general formula (f1-1) more specifically as a component is mentioned. As this polymer, the polymer (homopolymer) which consists only of the structural unit (f1) represented by a following formula (f1-1); a copolymer of the structural unit (f1) and the structural unit (a1); It is preferable that it is a copolymer of the structural unit (f1), the structural unit derived from acrylic acid or methacrylic acid, and the said structural unit (a1). Here, as the structural unit (a1) copolymerized with the structural unit (f1), a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate, 1-methyl-1-adamantyl (meth) Structural units derived from acrylates are preferred.

[Formula 74]

[Wherein, R is the same as above, Rf ¹⁰² and Rf ¹⁰³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf ¹⁰² and Rf ¹⁰³ are the same It may or may not be different. nf ¹ is an integer of 1 to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom.]

In the formula (f1-1), R bonded to the carbon atom at the α-position is the same as described above. As R, a hydrogen atom or a methyl group is preferable.

In the formula (f1-1), examples ^{of the halogen atom for Rf 102} and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable. Examples of the alkyl group having 1 to 5 carbon atoms for Rf ¹⁰² and Rf ^{103 include} the same groups as the alkyl group having 1 to 5 carbon atoms for R, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms for Rf ¹⁰² and Rf ¹⁰³ include groups in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as this halogen atom, A fluorine atom is especially preferable. Especially, as Rf ¹⁰² and Rf ¹⁰³ , a hydrogen atom, a fluorine atom, or a C1-C5 alkyl group is preferable, and a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group is preferable.

In formula (f1-1), nf ¹ is an integer of 1-5, the integer of 1-3 is preferable, and it is more preferable that it is 1 or 2.

In formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom.

The hydrocarbon group containing a fluorine atom may be any of linear, branched or cyclic, preferably having 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms. Especially preferred.

Moreover, as for the hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atoms in the said hydrocarbon group are fluorinated, it is more preferable that 50% or more is fluorinated, that 60% or more is fluorinated, It is especially preferable at the point which the hydrophobicity of the resist film at the time of immersion exposure becomes high.

Especially, as Rf ¹⁰¹ , a C1-C6 fluorohydrocarbon group is more preferable, and a trifluoromethyl group, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH(CF ₃ ) ₂ , - CH ₂ -CH ₂ -CF ₃ , -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ are particularly preferred.

(F) 1000-50000 are preferable, as for the weight average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography) of component, 5000-40000 are more preferable, and 10000-30000 are the most preferable. If it is below the upper limit of this range, there exists sufficient solubility with respect to the solvent for resists for use as a resist, and if it is more than the lower limit of this range, the water repellency of a resist film is favorable.

(F) 1.0-5.0 are preferable, as for the dispersion degree (Mw/Mn) of component, 1.0-3.0 are more preferable, and 1.0-2.5 are the most preferable.

In the resist composition of this embodiment, the component (F) may be used individually by 1 type, and may use 2 or more types together.

When the resist composition contains component (F), the content of component (F) is usually used in an amount of 0.5 to 10 parts by mass with respect to 100 parts by mass of component (A).

≪Organic solvent component (S)≫

The resist composition of the present embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as "(S) component").

As the component (S), any component can be appropriately selected from among conventionally known solvents for chemically amplified resist compositions, as long as it can dissolve each component to be used to form a uniform solution.

(S) As a component, For example, lactones, such as (gamma)-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol and dipropylene glycol; A compound having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, monomethyl ether, monoethyl ether of the polyhydric alcohol or compound having an ester bond, Derivatives of polyhydric alcohols such as compounds having an ether bond such as monoalkyl ethers such as monopropyl ether and monobutyl ether, or monophenyl ether [among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) is preferable]; cyclic ethers such as dioxane, esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; Anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene Aromatic organic solvents, such as dimethyl sulfoxide (DMSO), etc. are mentioned.

In the resist composition of the present embodiment, the component (S) may be used singly or as a mixed solvent of two or more kinds. Among them, at least one selected from the group consisting of PGMEA, PGME, γ-butyrolactone, EL, butyl acetate and cyclohexanone is preferable, and at least one selected from the group consisting of PGMEA, PGME and butyl acetate is more preferable Do.

Moreover, as (S) component, the mixed solvent which mixed PGMEA and a polar solvent is also preferable. The compounding ratio (mass ratio) may be appropriately determined in consideration of the compatibility of PGMEA and the polar solvent, etc., but preferably in the range of 1: 9 to 9: 1, more preferably 2: 8 to 8: 2 desirable.

More specifically, when EL, butyl acetate or cyclohexanone is blended as a polar solvent, the mass ratio of PGMEA:EL, butyl acetate or cyclohexanone 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, 2:8-8:2, More preferably, 3:7- It is 7:3. Moreover, the mixed solvent of PGMEA, PGME, and butyl acetate is also preferable.

In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, as a mixing ratio, the mass ratio of the former and the latter becomes like this. Preferably it becomes 70:30-95:5.

The amount of component (S) to be used is set so that the solid content concentration of the resist composition is 25 mass% or more. In the present specification, the solid content in the resist composition refers to components other than the component (S). The solid content concentration of the resist composition is calculated by the following formula.

Solid content concentration (mass %) = total mass of components other than (S) component/total mass of resist composition x 100

For example, when a resist composition consists of (A) component, (Z) component, (B) component, (D) component, and (S) component, solid content concentration (mass %) = [((A) component + (Z) component + (B) component + (D) component)/((A) component + (Z) component + (B) component + (D) component) + (S) component] x100.

By setting the solid content concentration of the resist composition to be 25 mass% or more, when the resist composition is applied to a substrate to form a resist film, a thick resist film (for example, a film thickness of 5 µm or more, preferably 7 µm or more) is formed. can do. The solid content concentration of the resist composition is not particularly limited as long as it is 25 mass% or more, and can be appropriately determined according to the desired thickness of the resist film. In general, the higher the solid content concentration, the thicker the resist film.

The upper limit of the solid content concentration of the resist composition is not particularly limited as long as the solid content can be dissolved. The solid content concentration of the resist composition is, for example, 60 mass% or less, preferably 55 mass% or less, and more preferably 50 mass% or less.

As a range of solid content concentration of a resist composition, 25-60 mass %, 25-55 mass %, or 25-50 mass % etc. are mentioned, for example.

In the resist composition of the present embodiment, a miscible additive, for example, an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, a dye, and the like may be suitably added to the resist composition of the present embodiment as desired. may be added.

In the resist composition of the present embodiment, after dissolving the resist material in the component (S), impurities and the like may be removed using a porous polyimide film, a porous polyamideimide film, or the like. For example, the resist composition may be filtered using a filter made of a porous polyimide film, a filter made of a porous polyamideimide film, a filter made of a porous polyimide film and a porous polyamideimide film, or the like. As said polyimide porous membrane and said polyamideimide porous membrane, the thing of Unexamined-Japanese-Patent No. 2016-155121 etc. are illustrated, for example.

The resist composition of the present embodiment described above has a solid content concentration of 25 mass% or more and contains the ionic liquid (Z).

Since the resist composition of the present embodiment has a solid content concentration of 25 mass% or more, a thick resist film (eg, a film thickness of 5 µm or more) is formed when a resist film is formed by applying it to a substrate. In such a thick resist film, cracks are likely to occur in the resist pattern. Moreover, since it is difficult for light to reach the bottom part, it is difficult to maintain the sensitivity at the time of exposure, and it is difficult to form a resist pattern of a favorable shape.

In the resist composition of the present embodiment, by containing the ionic liquid (Z), it is possible to achieve both crack resistance and high sensitivity. This is presumably because the stress of the resist film is relieved by the presence of the ionic liquid (Z) in the resist film formed using the resist composition.

(Resist pattern formation method)

The resist pattern forming method according to the second aspect of the present invention comprises the steps of forming a resist film on a support using the resist composition of the above-described embodiment, exposing the resist film, and developing the resist film after exposure. It is a method which has a process of forming a resist pattern.

As one embodiment of such a resist pattern formation method, the resist pattern formation method implemented as follows, for example is mentioned.

First, the resist composition of the above-described embodiment is applied on a support with a spinner or the like, and a bake (post-apply bake (PAB)) treatment is performed, for example, at a temperature of 80 to 150° C. for 40 to 120 seconds; Preferably, it is carried out for 60 to 90 seconds to form a resist film.

Next, with respect to the resist film, for example, using an exposure apparatus such as an electron beam drawing apparatus or an EUV exposure apparatus, exposure through a mask (mask pattern) in which a predetermined pattern is formed or electron beam not through a mask pattern After performing selective exposure by drawing by direct irradiation, etc., a baking (post-exposure bake (PEB)) process is 40-120 second at the temperature condition of 80-150 degreeC, for example, Preferably it is 60-90 second. .

Next, the resist film is developed. In the case of an alkali developing process, the developing treatment is performed using an alkali developing solution, and in the case of a solvent developing process, using the developing solution (organic type developing solution) containing an organic solvent.

After the developing treatment, preferably a rinse treatment is performed. As for the rinse treatment, in the case of an alkali developing process, water rinsing using pure water is preferable, and in the case of a solvent developing process, it is preferable to use the rinsing liquid containing an organic solvent.

In the case of a solvent developing process, after the said developing process or a rinse process, you may perform the process which removes the developing solution or rinse liquid adhering on the pattern with a supercritical fluid.

Drying is performed after developing or rinsing. Moreover, you may perform a baking process (post-baking) after the said developing process depending on a case.

In this way, a resist pattern can be formed.

It does not specifically limit as a support body, A conventionally well-known thing can be used, For example, the board|substrate for electronic components, the thing in which the predetermined|prescribed wiring pattern was formed, etc. are mentioned. More specifically, a silicon wafer, a metal substrate, such as copper, chromium, iron, and aluminum, a glass substrate, etc. are mentioned. As a material of a wiring pattern, copper, aluminum, nickel, gold|metal|money, etc. can be used, for example.

Moreover, as a support body, the thing in which the film|membrane of the inorganic type and/or organic type was formed on the above-mentioned board|substrate may be sufficient. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include an organic antireflection film (organic BARC) and an organic film such as a lower organic film in a multilayer resist method.

Here, in the multilayer resist method, at least one organic film (lower organic film) and at least one resist film (upper resist film) are formed on a substrate, and the resist pattern formed on the upper resist film is used as a mask. This is a method of patterning the lower organic film, and it is considered that a pattern with a high aspect ratio can be formed. That is, according to the multilayer resist method, since the required thickness can be ensured by the lower organic film, the resist film can be thinned and fine patterns with high aspect ratio can be formed.

In the multilayer resist method, basically, there is 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 (such as a metal thin film) are formed between the upper resist film and the lower organic film. It is divided into a method of forming a multilayer structure of three or more layers (three-layer resist method).

In the resist pattern formation method of this embodiment, since the resist composition of the above-described embodiment is used, a thick resist film is formed in step (i). It is preferable that it is 5 micrometers or more, and, as for the film thickness of the said resist film, it is more preferable that it is 7 micrometers or more, It is still more preferable that it is 8 micrometers or more. The upper limit of the film thickness of the resist film is, for example, 30 µm or less. As a range of the film thickness of the resist film formed in process (i), 5-30 micrometers is illustrated, for example, 7-20 micrometers is preferable, 7-15 micrometers is more preferable, 8-12 micrometers is more preferable. more preferably. The film thickness of the resist film can be adjusted by the solid content concentration of the resist composition used in step (i). That is, the higher the solid content concentration of the resist composition, the higher the thickness of the resist film can be formed.

The wavelength used for exposure is not specifically limited, ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. This can be done using radiation. The resist composition has high utility for KrF excimer lasers, ArF excimer lasers, EB or EUV applications, higher utility for KrF excimer lasers or ArF excimer lasers, and particularly high utility for KrF excimer lasers. That is, the resist pattern forming method of the present embodiment is particularly useful when the step of exposing the resist film includes exposing the resist film to KrF excimer laser light.

The exposure method of the resist film may be normal exposure (dry exposure) carried out in an inert gas such as air or nitrogen, or may be liquid immersion lithography.

Liquid immersion exposure is an exposure method in which 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.

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 the solvent is not particularly limited as long as it is within the above range.

Examples of the solvent having a refractive index greater than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicone-based solvent, and a hydrocarbon-based solvent.

Specific examples of the fluorine-based inert liquid include a liquid containing 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.} It is preferable that it is 70-180 degreeC, and, as for a boiling point, it is more preferable that it is 80-160 degreeC. If the fluorine-based inert liquid has a boiling point within the above range, it is preferable that the medium used for immersion can be removed by a simple method after the exposure is completed.

As the fluorine-based inert liquid, in particular, a perfluoroalkyl compound in which all hydrogen atoms in the alkyl group are substituted with fluorine atoms is preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.

Further, specifically, as the perfluoroalkyl ether compound, perfluoro(2-butyl-tetrahydrofuran) (boiling point 102° C.) is exemplified, and as the perfluoroalkylamine compound, perfluoro and lotributylamine (boiling point 174°C).

As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility, and the like.

As an alkali developing solution used for developing in an alkali developing process, 0.1-10 mass % tetramethylammonium hydroxide (TMAH) aqueous solution is mentioned, for example.

The organic solvent contained in the organic developer used for the developing treatment in the solvent development process should just be one capable of dissolving the component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specific examples thereof include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents and ether solvents, and hydrocarbon solvents.

A ketone-based solvent is an organic solvent containing C-C(=O)-C in its structure. The ester solvent is an organic solvent containing C-C(=O)-O-C in its structure. The alcohol-based solvent is an organic solvent containing an alcoholic hydroxyl group in its structure. "Alcoholic hydroxyl group" means the hydroxyl group couple|bonded with the carbon atom of the aliphatic hydrocarbon group. The nitrile-based solvent is an organic solvent containing a nitrile group in its structure. The amide-based solvent is an organic solvent containing an amide group in its structure. The etheric solvent is an organic solvent containing C-O-C in its structure.

Among organic solvents, there is also an organic solvent containing a plurality of types of functional groups that characterize each of the solvents in the structure. In that case, it is assumed that the organic solvent corresponds to any type of solvent containing a functional group that the organic solvent has. For example, diethylene glycol monomethyl ether shall correspond to any of the alcohol solvents and ether solvents in the said classification|category.

A hydrocarbon solvent is a hydrocarbon solvent which consists of hydrocarbons which may be halogenated and does not have substituents other than a halogen atom. As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.

As an organic solvent contained in an organic developing solution, a polar solvent is preferable among the above, and a ketone type solvent, an ester type solvent, a nitrile type solvent, etc. are preferable.

Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, and diisobutyl. Ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthylketone, isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), and the like. Among these, as the ketone solvent, methyl amyl ketone (2-heptanone) is preferable.

As an ester solvent, for example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, methoxy ethyl acetate, ethoxyethyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol Monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate , Diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl Acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate , 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4- Methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, Propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate , ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, and the like. Among these, as an ester solvent, butyl acetate is preferable.

As a nitrile-type solvent, acetonitrile, propionitrile, valeronitrile, butyronitrile, etc. are mentioned, for example.

A well-known additive can be mix|blended with an organic type developing solution as needed. As the additive, surfactant is mentioned, for example. Although it does not specifically limit as surfactant, For example, ionic or nonionic fluorine type and/or silicone type surfactant etc. can be used. As surfactant, a nonionic surfactant is preferable, and a nonionic fluorochemical surfactant or a nonionic silicone type surfactant is more preferable.

When mix|blending surfactant, the compounding quantity is 0.001-5 mass % normally with respect to the whole quantity of an organic type developing solution, 0.005-2 mass % is preferable, and its 0.01-0.5 mass % is more preferable.

The developing treatment can be carried out by a known developing method, for example, a method in which the support is immersed in a developer for a certain time (dip method), a method in which the developer is piled up on the surface of the support by surface tension and stopped for a certain time (paddle) method), a method of spraying a developer on the surface of a support (spray method), a method of drawing out a developer at a constant speed on a support rotating at a constant speed, and a method of continuously drawing out a developer while scanning a nozzle (dynamic dispensing method) and the like.

As the organic solvent contained in the rinsing solution used for the rinsing treatment after the development in the solvent development process, for example, from among the organic solvents used for the above organic developer, those that do not dissolve the resist pattern are appropriately selected and used. can 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 solvent selected from alcohol solvents and ester solvents is more preferable, Alcoholic solvents are particularly preferred.

The alcohol solvent used for the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be linear, branched or cyclic. Specifically, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4 - Octanol, benzyl alcohol, etc. are mentioned. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferable, and 1-hexanol and 2-hexanol are more preferable.

These organic solvents may be used individually by any 1 type, and may use 2 or more types together. Moreover, you may use it, mixing with organic solvents and water other than the above. However, in consideration of the development characteristics, the amount of water in the rinse liquid is preferably 30 mass% or less, more preferably 10 mass% or less, still more preferably 5 mass% or less, with respect to the total amount of the rinse liquid, 3 % by mass or less is particularly preferred.

A well-known additive can be mix|blended with a rinse liquid as needed. As the additive, surfactant is mentioned, for example. As for surfactant, the thing similar to the above is mentioned, A nonionic surfactant is preferable, and a nonionic fluorochemical surfactant or a nonionic silicone type surfactant is more preferable.

When mix|blending surfactant, the compounding quantity is 0.001-5 mass % normally with respect to the total amount of a rinse liquid, 0.005-2 mass % is preferable, and its 0.01-0.5 mass % is more preferable.

The rinsing process (washing process) using a rinsing liquid can be performed by a well-known rinsing method. As a method of the rinsing treatment, for example, a method of continuously extracting a rinse solution onto a support rotating at a constant speed (rotary coating method), a method of immersing the support in a rinse solution for a certain period of time (dip method), the surface of the support The method (spray method) etc. of spraying rinsing liquid are mentioned.

According to the resist pattern forming method of this embodiment described above, since the resist composition according to the first aspect described above is used, high sensitivity can be achieved and a resist pattern with few cracks can be formed.

Such a resist pattern formation method is useful for manufacturing a three-dimensional structure device.

Example

Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited by these examples.

<Preparation of resist composition>

(Examples 1 to 12, Comparative Examples 1 to 2)

Each of the components shown in Table 1 was mixed and dissolved to prepare resist compositions for each example.

In Table 1, each symbol has the following meaning, respectively. Numerical values in [ ] are compounding amounts (parts by mass). Solid content concentration is solid content concentration (mass %) = [((A) component + (B) component + (D) component + (Z) component)/((A) component + (B) component + (D) component + (Z) component + (S) component)] x 100.

(A)-1: A high molecular compound represented by the following formula (A-1). The weight average molecular weight (Mw) calculated|required by GPC measurement in terms of standard polystyrene is 10000, and the dispersion degree (Mw/Mn) is 1.4. ^The copolymer composition ratio (ratio (molar ratio) of each structural unit in the structural formula) determined by 13 C-NMR was l/m/n = 60/15/25.

[Formula 75]

(B)-1: An acid generator comprising a compound represented by the following formula (B-1).

(D)-1: A nitrogen-containing organic compound comprising a compound represented by the following formula (D-1).

[Formula 76]

(Z)-1: A compound represented by the following formula (IL)-1.

(Z)-2: A compound represented by the following formula (IL)-3.

(Z)-3: A compound represented by the following formula (IL)-14.

(Z)-4: A compound represented by the following formula (IL)-15.

(Z)-5: A compound represented by the following formula (IL)-16.

(Z)-6: A compound represented by the following formula (IL)-17.

(Z)-7: A compound represented by the following formula (IL)-18.

(Z)-8: A compound represented by the following formula (IL)-19.

(Z)-9: A compound represented by the following formula (IL)-20.

[Formula 77]

[Formula 78]

(S)-1: propylene glycol monomethyl ether

(S)-2: propylene glycol monomethyl ether acetate

(S)-3: butyl acetate

<Formation of resist pattern>

Process (i):

On an 8-inch silicon wafer subjected to hexamethyldisilazane (HMDS) treatment at 110° C. for 60 seconds, each resist composition was applied using a spinner. On a hotplate, a 15-micrometer-thick resist film was formed by performing the prebaking (PAB) process for 90 second at 140 degreeC, and drying.

Process (ii):

Next, the resist film was subjected to a KrF excimer laser (248 nm) and a mask pattern (binary mask) by using a KrF exposure apparatus NSR-S203B (manufactured by Nikon Corporation; NA (numerical aperture) = 0.68, σ = 0.40). It was interposed and selectively investigated.

Subsequently, post-exposure heating (PEB) treatment was performed at 110°C for 90 seconds.

Process (iii):

Next, alkali development was performed at 23 degreeC for 60 second conditions using 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, Tokyo Oka Kogyo Co., Ltd. make) as a developing solution.

Then, post-baking for 60 second was performed at 100 degreeC.

As a result, an isolated space pattern (hereinafter referred to as "IS pattern") having a space width of 5 µm and a pitch of 30 µm was formed.

[Evaluation of crack resistance]

The silicon wafer on which the IS pattern was formed by the said <Formation of a resist pattern> was put in the chamber of the scanning electron microscope S-9380 (made by Hitachi High-Technologies), and it vacuum-processed under 0.0001 Pa pressure for 60 second. The silicon wafer after vacuum processing was observed using the optical microscope, and the number of cracks was counted. The number of cracks was evaluated based on the following evaluation criteria. The results are shown in Table 2 as "cracks".

Evaluation standard

A: 0 cracks

B: 1 to 5 cracks

C: 6 or more cracks

[Evaluation of sensitivity]

In the above <Formation of resist pattern>, the optimum exposure dose Eop (mJ/cm 2 ) at which an IS pattern having a space width of 5 µm and a pitch of 30 µm was formed was determined. This was shown in Table 2 as "Eop (mJ/cm 2 )".

From the results shown in Table 2, it was confirmed that the resist compositions of Examples 1 to 12 were satisfactory in both crack resistance and sensitivity.

As mentioned above, although the preferred embodiment of this invention was described, this invention is not limited to these Examples. Without departing from the spirit of the present invention, addition, omission, substitution, and other changes are possible. The invention is not limited by the foregoing description, but only by the scope of the appended claims.

Claims (3)

A resist composition that generates an acid upon exposure and changes solubility in a developer by the action of the acid, the resist composition comprising:
A base component (A) whose solubility in a developer changes due to the action of an acid;
Ionic liquid (Z)
A resist composition having a solid content concentration of 25% by mass or more, comprising: The method of claim 1,
The resist composition wherein the content of the ionic liquid (Z) is greater than 0 parts by mass and less than 25 parts by mass with respect to 100 parts by mass of the base component (A). A resist pattern comprising a step of forming a resist film on a support using the resist composition according to claim 1 or 2, exposing the resist film, and developing the resist film after exposure to form a resist pattern. Formation method.