KR20210058698A - Resist composition and method of forming resist pattern - Google Patents

Abstract

Provided is a resist composition which includes an onium salt-based acid generating component (B), and a compound (D0) comprising an anion unit represented by general formula (d0) and a cation unit, wherein the onium salt-based acid generating component (B) and at least one cation unit of the compound (D0) have a cation having an electron withdrawing group. In formula (d0), Mm+ represents an m-valent organic cation, Rd0 is a substituent, and n is an integer of 2 or more.

Description

Resist composition and resist pattern formation method {RESIST COMPOSITION AND METHOD OF FORMING RESIST PATTERN}

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

This application claims priority based on Japanese Patent Application No. 2019-206433, filed in Japan on November 14, 2019, and Japanese Patent Application No. 2020-109820, filed in Japan on June 25, 2020, I use that content here.

In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, pattern miniaturization is rapidly progressing due to advances in lithography technology. As a method of miniaturization, in general, shorter wavelength (higher energy) of the exposure light source is performed.

Resist materials are required to have lithographic properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns of fine dimensions.

As a resist material that satisfies such a requirement, conventionally, a chemically amplified resist composition containing a base component whose solubility in a developer is changed by the action of an acid and an acid generator component that generates an acid by exposure has been used. .

In the formation of a resist pattern, the behavior of an acid generated from an acid generator component by exposure becomes a factor that has a great influence on lithography properties.

On the other hand, a chemically amplified resist composition in which an acid generator component and an acid diffusion control agent that controls diffusion of an acid generated from the acid generator component by exposure are used together have been proposed.

For example, Patent Document 1 contains a resin component whose solubility in a developer is changed by the action of an acid, an acid generator component, and a photoreactive agent having a cation moiety of a specific structure as an acid diffusion control agent. A resist composition is disclosed. This photoreactive agent causes an ion exchange reaction with an acid generated from the acid generator component to become a component exhibiting a quenching effect, and is generated from the acid generator component by the combination of the photoreactive agent component. The diffusion of the acid from the exposed portion of the resist film to the unexposed portion is controlled, and improvement of lithography characteristics is being sought.

Japanese Unexamined Patent Publication No. 2014-115386

In recent years, further advances in lithography technology, expansion of application fields, etc. are in progress, and pattern miniaturization is rapidly progressing. In connection with this, when manufacturing a semiconductor device or the like, a technique capable of forming a fine pattern having a pattern width of less than 100 nm in a good shape is required.

However, in the conventional resist composition described in Patent Document 1 described above, it has been difficult to achieve both high sensitivity and lithography characteristics.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a resist composition with high sensitivity and excellent lithography properties, and a method of forming a resist pattern using the resist composition.

In order to solve the above problems, the present invention adopts the following configuration.

That is, the first aspect of the present invention is a resist composition that generates an acid by exposure and changes its solubility in a developer by the action of an acid, and the solubility in a developer is changed by the action of the acid. (A), an onium salt-based acid generator component (B) that generates an acid by exposure, and a compound (D0) consisting of an anion moiety and a cation moiety represented by the following general formula (d0), and the onium salt-based At least one cation moiety of the acid generator component (B) and the compound (D0) is a resist composition, which is a cation having an electron withdrawing group.

[Formula 1]

[In the formula, M ^m+ represents an m-valent organic cation. m is an integer of 1 or more. R ^d0 is a substituent. p is an integer of 0-3. When p is 2 or 3, a plurality of R ^d0 may be the same or different. q is an integer of 0-3. n is an integer of 2 or more. However, it is n + p ≤ (q × 2) + 5.]

The second aspect of the present invention is a step of forming a resist film on a support using the resist composition according to the first aspect, a step of exposing the resist film, and a step of developing the resist film after the exposure to form a resist pattern. It is a method of forming a resist pattern having

Advantageous Effects of Invention According to the present invention, it is possible to provide a resist composition having high sensitivity and excellent lithography properties, and a method of forming a resist pattern using the resist composition.

In the present specification and claims, the term "aliphatic" is a relative concept with respect to aromatics, and is defined to mean a group, compound, etc. that do not have aromaticity.

Unless otherwise specified, the "alkyl group" shall include a linear, branched, and cyclic monovalent saturated hydrocarbon group. The alkyl group in the alkoxy group is also the same.

The "alkylene group" shall include a linear, branched and cyclic divalent saturated hydrocarbon group unless otherwise specified.

Examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The "constituent unit" means a monomer unit (monomer unit) constituting a high molecular compound (resin, polymer, copolymer).

In the case of describing "you may have a substituent", both 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 are included.

"Exposure" is a concept including the whole irradiation of radiation.

The "acid decomposable group" is a group having acid decomposability in which at least a part of the bonds in the structure of the acid decomposable group can be cleaved by the action of an acid.

As an acid-decomposable group whose polarity is increased by the action of an acid, for example, a group decomposing by the action of an acid to generate a polar group is mentioned.

Examples of the polar group include a carboxyl group, a hydroxyl group, an amino group, and a sulfo group (-SO ₃ H).

More specifically, as the acid-decomposable group, a group in which the polar group is protected by an acid dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid dissociable group) is mentioned.

"Acid dissociable group" means (i) a group having an acid dissociable property capable of cleaving a bond between the acid dissociable group and an atom adjacent to the acid dissociable group by the action of an acid, or (ii) an acid It refers to both groups of groups capable of cleaving a bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group by causing a decarboxylation reaction to occur after some bonds are cleaved by the action of.

The acid-dissociable group constituting the acid-dissociable group needs to be a group having a lower polarity than the polar group generated by dissociation of the acid-dissociable group. Accordingly, when the acid-dissociable group is dissociated by the action of an acid, the acid-dissociable group A polar group with higher polarity results in an increase in polarity. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer is relatively changed, so that the solubility increases when the developer is an alkaline developer, and the solubility decreases when the developer is an organic developer.

The "substrate component" is an organic compound having a film-forming ability. Organic compounds used as the base component are roughly classified into non-polymers and polymers. As the non-polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, in the case of a "low molecular weight compound", a non-polymer having a molecular weight of 500 or more and less than 4000 is indicated. As a polymer, one having a molecular weight of 1000 or more is usually used. Hereinafter, in the case of "resin", "polymer compound" or "polymer", a polymer having a molecular weight of 1000 or more is indicated. As the molecular weight of the polymer, the mass average molecular weight in terms of polystyrene by GPC (gel permeation chromatography) is used.

The "derived structural unit" means a structural unit constituted by cleavage of multiple bonds between carbon atoms, for example, ethylenic double bonds.

In the "acrylic acid ester", a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent. ^{The substituent (R αx} ) that replaces the hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than a hydrogen atom. In addition, ^{itaconic acid diester in which the substituent (R αx} ) is substituted with a substituent containing an ester bond, and ^{α hydroxyacrylic ester in which the substituent (R αx} ) is substituted with a hydroxyalkyl group or a group modified with its hydroxyl group are also included. do. In addition, the carbon atom at the α-position of the acrylic acid ester refers to a carbon atom to which the carbonyl group of acrylic acid is bonded, unless otherwise noted.

Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic acid ester.

The term "derivative" is a concept including those in which the hydrogen atom at the α-position of the target compound is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. Examples of these derivatives include those obtained by substituting an organic group for a hydrogen atom in the hydroxyl group of the target compound in which the hydrogen atom at the α-position may be substituted with a substituent; Examples of the compound in which a substituent other than a hydroxyl group is bonded to the target compound in which the hydrogen atom at the α-position may be substituted with a substituent may be mentioned. In addition, the α-position refers to the first carbon atom adjacent to the functional group, unless otherwise specified.

Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include those similar to ^{R αx.}

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

(Resist composition)

In the resist composition of the present embodiment, an acid is generated by exposure, and the solubility in a developer is changed by the action of the acid.

Such a resist composition includes a base component (A) whose solubility in a developer is changed by the action of an acid (hereinafter, also referred to as ``component (A)''), and an acid generator component (B) that generates an acid by exposure ( Hereinafter, also referred to as "component (B)") and a compound (D0) composed of an anion moiety and a cation moiety represented by the general formula (d0) (hereinafter also referred to as a “component (D0)”) are contained. In addition, at least one cation portion of the component (B) and the component (D0) in the resist composition is a cation having an electron withdrawing group.

When a resist film is formed using the resist composition of the present embodiment and selective exposure is performed on the resist film, an acid is generated from the component (B) in the exposed portion of the resist film, and the component (A) is caused by the action of the acid. While the solubility in the developer of the resist film is changed, the solubility of the component (A) in the developer does not change in the unexposed portion of the resist film, so that a difference in solubility in the developer is generated between the exposed portion and the unexposed portion. Therefore, when the resist film is developed, when the resist composition is positive, the exposed portion of the resist film is dissolved and removed to form a positive resist pattern, and when the resist composition is a negative type, the unexposed portion of the resist film is dissolved and removed. Type resist pattern is formed.

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

<(A) component>

In the resist composition of the present embodiment, the component (A) preferably contains a resin component (A1) whose solubility in a developer is changed by the action of an acid (hereinafter also referred to as "component (A1)"). By using the component (A1), since the polarity of the substrate 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 the component (A), at least the component (A1) is used, and other high molecular compounds and/or low molecular compounds may be used in combination with the component (A1).

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

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

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

・(A1) Ingredient

The component (A1) is a resin component whose solubility in a developer is changed by the action of an acid. As the component (A1), it is preferable to have a structural unit (a1) containing an acid-decomposable group whose polarity is increased by the action of an acid.

In addition to the structural unit (a1), the component (A1) may have other structural units as necessary.

≪Structural unit (a1)≫

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

Examples of the acid dissociable group include those proposed so far as the acid dissociable group of the base resin for chemically amplified resist compositions.

It is proposed as an acid dissociable group of a base resin for a chemically amplified resist composition, specifically, ``acetal type acid dissociable group'', ``tertiary alkyl ester type acid dissociable group'', and ``third class An alkyloxycarbonyl acid dissociable group".

Acetal acid dissociation genitals:

As an acid-dissociable group which protects a carboxy group or a hydroxyl group among the said polar groups, an acid-dissociable group represented by the following general formula (a1-r-1) (hereinafter, it may be called "acetal-type acid-dissociable group"), for example. Can be mentioned.

[Formula 2]

[In the formula, Ra' ¹ and Ra' ² are a hydrogen atom or an alkyl group. Ra' ³ is a hydrocarbon group, and Ra' ³ may be ^{bonded to any of Ra' 1} and Ra' ² to form a ring.]

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

When Ra' ¹ or Ra' ² is an alkyl group, examples of the alkyl group include the same alkyl group as the substituent which may be bonded to the carbon atom at the α-position in the description of the α-substituted acrylate ester, and has 1 to An alkyl group of 5 is preferred. Specifically, a linear or branched alkyl group is preferably mentioned. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. are mentioned, and a methyl group or an ethyl group It is more preferable and a methyl group is especially preferable.

In 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, an n-propyl group, an n-butyl group, an n-pentyl group, etc. are mentioned. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched-chain alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and isopropyl group It is desirable.

When Ra' ³ becomes a cyclic hydrocarbon group, the hydrocarbon group 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 excluding one hydrogen atom from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group which is a polycyclic group, a group excluding one hydrogen atom from a polycycloalkane is preferable, and as the polycycloalkane, a one having 7 to 12 carbon atoms is preferable, and 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.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; And an aromatic heterocyclic ring in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group for Ra' ³ include a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); A group excluding one hydrogen atom from an aromatic compound containing two or more aromatic rings (eg, biphenyl, fluorene, etc.); A group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or the aromatic heterocycle is substituted with an alkylene group (e.g., benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2 -Arylalkyl groups, such as a naphthyl ethyl group, etc.), etc. are mentioned. The number of carbon atoms of the alkylene group bonded to the aromatic hydrocarbon ring or the aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1 to carbon number.

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, these substituents are collectively ^{referred to as "Ra x5} "), and the like. Here, R ^P1 is a C1-C10 monovalent chain saturated hydrocarbon group, a C3-C20 monovalent aliphatic cyclic saturated hydrocarbon group, or a C6-C30 monovalent aromatic hydrocarbon group. Moreover, R ^P2 is a single bond, a C1-C10 divalent chain saturated hydrocarbon group, a C3-C20 divalent aliphatic cyclic saturated hydrocarbon group, or a C6-C30 divalent aromatic hydrocarbon group. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, the alicyclic saturated hydrocarbon group and the aromatic hydrocarbon group of ^{R P1} and R ^{P2 may be substituted with fluorine atoms.} The aliphatic cyclic hydrocarbon group may have one or more of the substituents alone, and may have one or more of each of the plurality of substituents.

As a C1-C10 monovalent chain saturated hydrocarbon group, 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, for example.

As a C3-C20 monovalent aliphatic cyclic saturated hydrocarbon group, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, 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, a Polycyclic aliphatic saturated hydrocarbon groups, such as a damanyl group, are mentioned.

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

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

Tertiary alkyl ester type acid dissociable group:

Among the polar groups, examples of the acid dissociable group that protects the carboxyl 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), what is constituted by an alkyl group is hereinafter sometimes referred to as a "tertiary alkyl ester type acid dissociable group" for convenience.

[Formula 3]

[In the formula, 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, or 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 I 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 those similar to those of ^{Ra' 3 described 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 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 bonded to each other and are independent hydrocarbon groups, a group represented by the following general formula (a1-r2-4) is preferably mentioned.

[Formula 4]

[In formula (a1-r2-1), Ra' ¹⁰ represents a linear or branched linear or branched alkyl group having 1 to 12 carbon atoms which may be partially substituted with a halogen atom or a hetero atom-containing group. 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 forming a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of this cyclic hydrocarbon group may be substituted. Each of Ra ¹⁰¹ to Ra ¹⁰³ independently represents 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 ¹⁰¹ to Ra ¹⁰³ 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 forming an aliphatic cyclic group together with Yaa. Ra ¹⁰⁴ is an aromatic hydrocarbon group which may have a substituent. In formula (a1-r2-4), Ra' ¹² and Ra' ¹³ are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Some or all of the hydrogen atoms of this chain saturated hydrocarbon group may be substituted. Ra' ¹⁴ is a hydrocarbon group which may have a substituent. * Represents a bonding hand.]

In the above formula (a1-r2-1), Ra' ¹⁰ is a linear or branched alkyl group having 1 to 12 carbon atoms which may be partially substituted with a halogen atom or a hetero atom-containing group.

The linear alkyl group for Ra' ¹⁰ has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms.

Examples of the branched-chain alkyl group for Ra' ¹⁰ include those similar to those of ^{Ra' 3 described above.}

The alkyl group for Ra' ¹⁰ may be partially substituted with a halogen atom or a hetero atom-containing group. For example, some of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a hetero atom-containing group. Moreover, a part of carbon atoms (methylene group, etc.) constituting the alkyl group may be substituted with a hetero atom-containing group.

Examples of the hetero atom here include an oxygen atom, a sulfur atom, and a nitrogen atom. As the hetero atom-containing group, (-O-), -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C (=O)-NH-, -NH-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, etc. are mentioned.

In the formula (a1-r2-1), Ra' ¹¹ (an aliphatic cyclic group formed together with the carbon atom to which Ra' ^{10 is bonded) is a monocyclic group of Ra' 3 in} the formula (a1-r-1) or The group mentioned as the aliphatic hydrocarbon group (alicyclic hydrocarbon group) which is a lye type group is preferable. Among these, a monocyclic alicyclic hydrocarbon group is preferable, specifically, a cyclopentyl group and a cyclohexyl group are more preferable, and a cyclopentyl group is still more preferable.

In the formula (a1-r2-2), as the cyclic hydrocarbon group in which Xa is formed with Ya, the cyclic monovalent hydrocarbon group in Ra′ ³ in the formula (a1-r-1) (aliphatic hydrocarbon Group) from which one or more hydrogen atoms are further removed.

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

In the formula (a1-r2-2) ^{, examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra 101} to Ra ¹⁰³ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, Hexyl group, heptyl group, octyl group, decyl group, etc. are mentioned.

Examples of the saturated monovalent aliphatic cyclic hydrocarbon group having 3 to 20 carbon atoms in Ra ¹⁰¹ to Ra ¹⁰³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooxy group. Monocyclic aliphatic saturated hydrocarbon groups such as a yl 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, a And polycyclic aliphatic saturated hydrocarbon groups such as damanyl group.

Ra ¹⁰¹ to Ra ¹⁰³ are particularly preferably a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom, a methyl group, and an ethyl group, from the viewpoint of ease of synthesis. It is particularly preferred.

Examples of the substituents which the chain saturated hydrocarbon group represented by Ra ¹⁰¹ to Ra ¹⁰³ or the alicyclic saturated hydrocarbon group have are, for example, the same groups as ^{Ra x5 described above.}

As ^{a group containing a carbon-carbon double bond formed by two or more of Ra 101} to Ra ¹⁰³ bonded to each other to form a cyclic structure, for example, a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, and methyl A cyclohexenyl group, a cyclopentylidene ethenyl group, a cyclohexylidene ethenyl group, and the like are mentioned. Among these, from the viewpoint of ease of synthesis, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneethenyl group are preferable.

In the formula (a1-r2-3), the aliphatic cyclic group formed by Xaa with Yaa is preferably a group as an aliphatic hydrocarbon group which 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 104} include a group excluding one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra ¹⁰⁴ is preferably a group excluding one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group excluding one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene, and more preferably benzene, Groups excluding one or more hydrogen atoms from naphthalene or anthracene are more preferred, groups excluding one or more hydrogen atoms from benzene or naphthalene are particularly preferred, and groups excluding one or more hydrogen atoms from benzene are most preferred.

^{Examples of the substituent that Ra 104} 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, an alkoxy group (methoxy group, ethoxy group, propoxy Period, butoxy group, etc.), alkyloxycarbonyl group, etc. are mentioned.

In formula (a1-r2-4), Ra' ¹² and Ra' ¹³ are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. The monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms for Ra′ ¹² and Ra′ ¹³ is the same as the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms for ^{Ra 101} to Ra ^{103 described above.} Can be lifted. Some or all of the hydrogen atoms of this chain saturated hydrocarbon group may be substituted.

Ra ^'12 and Ra' ¹³ is, inter alia, is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms are preferred, and an alkyl group of 1 to 5 carbon atoms, and more preferably, a methyl group, an ethyl group is more preferable, and methyl group is particularly preferred.

When the chain saturated hydrocarbon group represented by the above Ra' ¹² and Ra' ¹³ is substituted, examples of the substituent include the same group as that of ^{Ra x5 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.

The linear alkyl group for Ra' ¹⁴ preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and still more preferably 1 or 2. Specifically, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, etc. are mentioned. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched-chain alkyl group for Ra' ¹⁴ preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and isopropyl group It is desirable.

When Ra' ¹⁴ becomes a cyclic hydrocarbon group, the hydrocarbon group 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 excluding one hydrogen atom from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group which is a polycyclic group, a group excluding one hydrogen atom from a polycycloalkane is preferable, and as the polycycloalkane, a one having 7 to 12 carbon atoms is preferable, and specifically, adamantane, norbornane, iso Bornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

Examples of the aromatic hydrocarbon group for Ra′ ¹⁴ include the same as the aromatic hydrocarbon group for Ra ¹⁰⁴ . Among them, Ra' ¹⁴ is preferably a group excluding at least one hydrogen atom from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group excluding at least one hydrogen atom from benzene, naphthalene, anthracene or phenanthrene, and more preferably benzene , A group excluding one or more hydrogen atoms from naphthalene or anthracene is more preferred, a group excluding one or more hydrogen atoms from naphthalene or anthracene is particularly preferred, and a group excluding one or more hydrogen atoms from naphthalene is most preferred.

Examples of ^{the substituent that Ra' 14} may have include the same substituents that ^{Ra 104 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 or 2 position of the naphthyl group. It can be any position.

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

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

[Formula 5]

[Formula 6]

[Formula 7]

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

[Formula 8]

[Formula 9]

[Formula 10]

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

[Formula 11]

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

[Formula 12]

Tertiary alkyloxycarbonyl acid dissociable group:

Among the polar groups, the acid dissociable group 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).

[Formula 13]

[In the formula, each of Ra' ⁷ to Ra' ⁹ is an alkyl group.]

In formula (a1-r-3) ^{, each of Ra' 7} to Ra' ⁹ is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms.

Moreover, the total number of carbon atoms of each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4 carbon atoms.

As the structural unit (a1), 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, a structural unit derived from acrylamide, a constitution derived from a hydroxystyrene or hydroxystyrene derivative Hydrogen in -C(=O)-OH of a constituent unit in which at least part of the hydrogen atoms in the hydroxyl group of the unit is protected by a substituent containing the acid decomposable group, a constituent unit derived from a vinylbenzoic acid or a vinylbenzoic acid derivative And structural units in which at least part of the 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 14]

[In formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. 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 above general formula (a1-r-1) or (a1-r-2). Wa ¹ is an 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 alkyl group having 1 to 5 carbon atoms of R 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, or 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. As the halogen atom, a fluorine atom is particularly 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 a hydrogen atom or a methyl group is most preferable from industrial availability.

In the formula (a1-1), the ^{divalent hydrocarbon group in 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 specifically, as the aliphatic hydrocarbon group, a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure, and the like can be exemplified.

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 -], and 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, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkyl methylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -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; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as an alkyl tetramethylene group, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -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.

As the aliphatic hydrocarbon group containing a ring in the above structure, an alicyclic hydrocarbon group (a group excluding two hydrogen atoms from the aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group And groups in which the 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 those similar to the linear or branched aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group excluding two hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group excluding two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a C7 to C12 group, 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.}

Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, still more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring possessed by the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; And an aromatic heterocyclic ring in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.

Specifically as the aromatic hydrocarbon group, a group in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring (arylene group); A group in which one of the hydrogen atoms of the group (aryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring is substituted with an alkylene group (e.g., benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group , A group in which one further hydrogen atom has been removed from the aryl group in an arylalkyl group such as 1-naphthylethyl group and 2-naphthylethyl group). The number of carbon atoms in the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 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 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 having no aromaticity, and may be saturated or unsaturated, and usually, it is preferable that it is saturated. As the aliphatic hydrocarbon group, a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a linear or branched aliphatic hydrocarbon group, and an aliphatic hydrocarbon group containing a ring in the structure are combined One can be cited. The n _a2 + 1 valency is preferably 2 to 4, and more preferably 2 or 3.

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 15]

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

[Formula 22]

The structural unit (a1) of the component (A1) may be one or two or more.

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

Among these, as the structural unit (a1), it is particularly preferable to include a structural unit represented by the following general formula (a1-1-1).

[Formula 23]

[In the formula, Ra ¹ "is an acid dissociable group represented by a 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. Among them, it is preferable to select the one in which the acid-dissociable group is a cyclic group from the viewpoint that the reactivity becomes high in EB use or EUV use.

In said formula (a1-1-1) ^{, it is preferable that Ra 1} "is an acid dissociable group represented by general formula (a1-r2-1) among the above.

The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mole%, and 10 to 75 mole% with respect to the total (100 mole%) of all structural units constituting the component (A1). It is more preferable, 30-70 mol% is still more preferable, and 40-60 mol% is especially preferable.

By making the ratio of the structural unit (a1) within the above-described preferable range, the efficiency of the deprotection reaction and the solubility of the developer can be properly ensured, so that the effects of the present invention are more easily obtained.

≪Other structural units≫

In addition to the above-described structural unit (a1), the component (A1) may have other structural units as necessary.

Examples of other structural units include structural units (a10) represented by general formula (a10-1) described later; Structural unit (a2) containing a lactone-containing cyclic group, an -SO ₂ -containing cyclic group, or a carbonate-containing cyclic group; Structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group; Structural unit (a4) containing an acid non-dissociable aliphatic cyclic group; And the structural unit (st) derived from styrene or a styrene derivative.

Constituent unit (a10):

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

[Formula 24]

[In the formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Ya ^x1 is a single bond or a divalent connecting group. Wa ^x1 is an aromatic hydrocarbon group which may have a substituent. n _ax1 is an integer of 1 or more.]

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, and 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, and the like.

The halogenated alkyl group having 1 to 5 carbon atoms for R 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. As the halogen atom, a fluorine atom is particularly 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 ease of industrial availability, a hydrogen atom, a methyl group or a trifluoromethyl group is more preferable, and a hydrogen atom or a methyl group is further It is preferred, and a methyl group is particularly preferred.

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

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

Divalent hydrocarbon group which may have a substituent:

When Ya ^x1 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 in ^{Ya x1}

The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and it is preferable that it is usually saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the 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 -], and 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, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkyl methylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -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; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as an alkyl tetramethylene group, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -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, and a carbonyl group substituted with a fluorine atom.

Aliphatic hydrocarbon group containing a ring in the structure

As the aliphatic hydrocarbon group containing a ring in its structure, a cyclic aliphatic hydrocarbon group (a group excluding two hydrogen atoms from the aliphatic hydrocarbon ring), which may contain a substituent containing a hetero atom in the ring structure, and the cyclic aliphatic A group in which a hydrocarbon group is bonded to the 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 the linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those similar to 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 excluding two hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group excluding two hydrogen atoms from the polycycloalkane is preferable, and the polycycloalkane is preferably a C7 to C12 group, specifically adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

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.

As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and methoxy The timing and ethoxy group are more preferable.

The halogen atom as the substituent is preferably a fluorine atom.

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 atom.

In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O- are preferable. .

· · Aromatic hydrocarbon group in ^{Ya x1}

The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; And an aromatic heterocyclic ring in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include a group (arylene group or heteroarylene group) in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocycle; A group excluding two hydrogen atoms from an aromatic compound containing two or more aromatic rings (for example, biphenyl, fluorene, etc.); A group in which one hydrogen atom of the group (aryl group or heteroaryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g., benzyl group, phenethyl group, 1-naph A group in which one further hydrogen atom has been removed from the aryl group in an arylalkyl group such as a ylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group), and the like. The number of carbon atoms of the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1 to carbon number.

In the aromatic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, 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 a substituent for substituting a hydrogen atom possessed by the cyclic aliphatic hydrocarbon group.

Divalent linking groups containing heteroatoms:

When Ya ^x1 is a divalent linking group containing a hetero atom, preferred as the linking group are -O-, -C(=O)-O-, -OC(=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-, 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- [In the formula, Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m" Is an integer of 0-3.] etc. are mentioned.

The divalent linking group containing the hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)- In the case, the H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5.

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 -Y ²¹ -S(=O) ₂ -OY ²² -, Y ²¹ and Y ²² are each independently The divalent hydrocarbon group is a divalent hydrocarbon group which may have a substituent, and examples of the divalent hydrocarbon group are the same as those described in the description of the divalent linking group in ^{Ya x1 (a divalent hydrocarbon group which may have a substituent).} .

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. The alkyl group in the alkylmethylene group is preferably a C1-C5 linear alkyl group, more preferably a C1-C3 linear alkyl group, and most preferably a methyl group.

In the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, and more preferably 0 or 1 And 1 is particularly preferred. In short, 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 -.} And a group represented by the formula -(CH ₂ ) _a'- C(=O)-O-(CH ₂ ) _b' -is preferable In the formula, a'is an integer of 1 to 10, and An integer is preferable, an integer of 1-5 is more preferable, 1 or 2 is still more preferable, and 1. b'is an integer of 1-10, an integer of 1-8 is preferable, and 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 ^x1 is 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 is preferable, and a single bond and an ester bond [-C(=O)-O-, -OC(=O)-] are more preferable.

In the formula (a10-1), Wa ^x1 is an aromatic hydrocarbon group which may have a substituent.

_Examples of the aromatic hydrocarbon group for Wa ^x1 include groups excluding (n ax1 + 1) hydrogen atoms from the aromatic ring which may have a substituent. 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. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; And aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

In addition, as ^{the aromatic hydrocarbon group in Wa x1} _{, a group excluding (n ax1} + 1) hydrogen atoms from an aromatic compound containing an aromatic ring which may have two or more substituents (for example, biphenyl, fluorene, etc.) Can be lifted.

Among the above, Wa ^x1 _{is preferably a group excluding (n ax1} + 1) hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, and more preferably a group excluding _{(n ax1 + 1) hydrogen atoms from benzene or naphthalene.} And a _{group excluding (n ax1} + 1) hydrogen atoms from benzene is more preferable.

The aromatic hydrocarbon group in Wa ^x1 may or may not 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 are the same as those mentioned as the substituent of the cyclic aliphatic hydrocarbon group in ^{Ya x1.} The substituent is preferably a C1-C5 linear or branched alkyl group, more preferably a C1-C3 linear or branched alkyl group, more preferably an ethyl group or a methyl group, and a methyl group Is particularly preferred. It is preferable that the aromatic hydrocarbon group in Wa ^{x1 does not have a substituent.}

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, even more preferably 1, 2 or 3, and 1 or 2 Is particularly preferred.

Below, a specific example of the structural unit (a10) represented by the said formula (a10-1) is shown.

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

[Formula 25]

[Formula 26]

[Formula 27]

[Formula 28]

The structural unit (a10) of the component (A1) may be one or two or more.

When the component (A1) has a structural unit (a10), the proportion of the structural unit (a10) in the component (A1) is 5 to the total (100 mol%) of all structural units constituting the component (A1). 80 mol% is preferable, 10 to 75 mol% is more preferable, 30 to 70 mol% is still more preferable, and 40 to 60 mol% is particularly preferable.

By making the ratio of the structural unit (a10) within the above preferable range, the efficiency of supplying the proton in the resist film is increased, and the solubility of the developer can be properly secured, so that the effects of the present invention are more easily obtained.

Constituent unit (a2):

In addition to the structural unit (a1), the component (A1) further comprises a lactone-containing cyclic group, an -SO ₂ -containing cyclic group, or a carbonate-containing cyclic group (a2) (however, 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 of the structural unit (a2) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used for formation of the resist film. . In addition, by having the structural unit (a2), for example, by appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and adjusting the solubility at the time of development appropriately, lithography characteristics The back becomes good.

The "lactone-containing cyclic group" represents a cyclic group containing a ring (lactone ring) containing -O-C(=O)- in the cyclic skeleton. The lactone ring is counted as the first ring, and when only the lactone ring is used, it is called a monocyclic group, and when it has a further other ring structure, it is called a polycyclic group regardless of its 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 one can be used. Specifically, groups represented by the following general formulas (a2-r-1) to (a2-r-7) are exemplified.

[Formula 29]

[In the formula, 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 an -SO ₂ -containing cyclic group; even if A" contains an oxygen atom (-O-) or a sulfur atom (-S-) It is a C1-C5 alkylene group, an oxygen atom, or a sulfur atom, n'is an integer of 0-2, 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. It is preferable that the alkyl group is linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group, and the like are mentioned. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly 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. Specifically, the group in which the alkyl group and oxygen atom (-O-) referred to as the alkyl group in the above Ra′ ^{21 are connected is mentioned.}

The halogen atom for Ra' ²¹ is preferably a fluorine atom.

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. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

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

As the alkyl group for R", any of linear, branched and cyclic may be sufficient, and the number of carbon atoms is preferably 1 to 15.

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

When R" is a cyclic alkyl group, it is preferably 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, it is substituted with a fluorine atom or a fluorinated alkyl group. A group excluding one or more hydrogen atoms from a monocycloalkane that may or may not be used; a group excluding one or more hydrogen atoms from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. More specifically, groups excluding one or more hydrogen atoms from monocycloalkane such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. And groups excluding one or more hydrogen atoms from the polycycloalkane.

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

The carbonate-containing cyclic group for R" is the same as the carbonate-containing cyclic group described later, and specifically, groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are exemplified.

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) The group shown can be mentioned.

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

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 The alkylene group of is preferably 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 terminal or carbon atoms of, for example, O-CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ -etc. are mentioned. As A", a C1-C5 alkylene group or -O- is preferable, a C1-C5 alkylene group is more preferable, and a methylene group is most preferable.

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

[Formula 30]

[Chemical Formula 31]

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

As the -SO ₂ -containing cyclic group, more specifically, groups represented by the following general formulas (a5-r-1) to (a5-r-4) are exemplified.

[Formula 32]

[In the formula, 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 an -SO ₂ -containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, oxygen It is an atom or a sulfur atom, and n'is an integer of 0-2.]

In the general formulas (a5-r-1) to (a5-r-2), A" is the general formula (a2-r-2), (a2-r-3), (a2-r-5) It is the 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 each of the general formulas (a2-r-1) to (a2).} The same thing as the explanation for ^{Ra' 21} in -r-7) can be mentioned.

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

[Formula 33]

[Formula 34]

[Formula 35]

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

The carbonate ring-containing cyclic group is not particularly limited, and any one can be used. Specifically, groups represented by the following general formulas (ax3-r-1) to (ax3-r-3) are exemplified.

[Chemical Formula 36]

[In the formula, Ra' ^x31 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 an -SO ₂ -containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, oxygen It is an atom or a sulfur atom, p'is an integer of 0-3, and q'is 0 or 1.]

In the general formulas (ax3-r-2) to (ax3-r-3), A" is the general formula (a2-r-2), (a2-r-3), (a2-r-5) It is the 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 each of the general formulas (a2-r-1) to (a2).} The same thing as the explanation for ^{Ra' 21} in -r-7) can be mentioned.

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

[Chemical Formula 37]

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 38]

[In the formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. 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 an -SO ₂ -containing cyclic group.]

In said 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 a hydrogen atom or a methyl group is particularly preferable from industrial availability.

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

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 in Ya ²¹

The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and it is preferable that it is usually saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the 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 -], and 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, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkyl methylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -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; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as an alkyl tetramethylene group, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -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, and a carbonyl group substituted with a fluorine atom.

Aliphatic hydrocarbon group containing a ring in the structure

As the aliphatic hydrocarbon group containing a ring in its structure, a cyclic aliphatic hydrocarbon group (a group excluding two hydrogen atoms from the aliphatic hydrocarbon ring), which may contain a substituent containing a hetero atom in the ring structure, and the cyclic aliphatic A group in which a hydrocarbon group is bonded to the 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 the linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those similar to 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 excluding two hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group excluding two hydrogen atoms from the polycycloalkane is preferable, and the polycycloalkane is preferably a C7 to C12 group, specifically adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, etc. are mentioned.

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.

As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and methoxy The timing and ethoxy group are more preferable.

The halogen atom as the substituent is preferably a fluorine atom.

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 atom.

In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O- are preferable. .

· · Aromatic hydrocarbon group in ^{Ya 21}

The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; And an aromatic heterocyclic ring in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include a group (arylene group or heteroarylene group) in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocycle; A group excluding two hydrogen atoms from an aromatic compound containing two or more aromatic rings (for example, biphenyl, fluorene, etc.); A group in which one hydrogen atom of the group (aryl group or heteroaryl group) excluding one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g., benzyl group, phenethyl group, 1-naph A group in which one further hydrogen atom has been removed from the aryl group in an arylalkyl group such as a ylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group), and the like. The number of carbon atoms of the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1 to carbon number.

In the aromatic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, 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 a substituent for substituting a hydrogen atom possessed by the cyclic aliphatic hydrocarbon group.

Divalent linking groups containing heteroatoms:

When Ya ²¹ is a divalent linking group containing a hetero atom, preferred examples of the linking group are -O-, -C(=O)-O-, -OC(=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-, 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- [In the formula, Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m" Is an integer of 0-3.] etc. are mentioned.

The divalent linking group containing the hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)- In the case, the H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5.

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 -Y ²¹ -S(=O) ₂ -OY ²² -, Y ²¹ and Y ²² are each independently Is a divalent hydrocarbon group which may have a substituent, and the divalent hydrocarbon group is the same as (divalent hydrocarbon group which may have a substituent) in the description as 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. The alkyl group in the alkylmethylene group is preferably a C1-C5 linear alkyl group, more preferably a C1-C3 linear alkyl group, and most preferably a methyl group.

In the group represented by the formula -[Y ²¹ -C(=O)-O] _m" -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, and more preferably 0 or 1 And 1 is particularly preferred. In short, 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 -.} And a group represented by the formula -(CH ₂ ) _a'- C(=O)-O-(CH ₂ ) _b' -is preferable In the formula, a'is an integer of 1 to 10, and An integer is preferable, an integer of 1-5 is more preferable, 1 or 2 is still more preferable, and 1. b'is an integer of 1-10, an integer of 1-8 is preferable, and 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, an -SO ₂ -containing cyclic group, or a carbonate-containing cyclic group.

As the lactone-containing cyclic group, -SO ₂ ^{-containing cyclic group, and carbonate-containing cyclic group for Ra 21} , respectively, groups represented by the aforementioned general formulas (a2-r-1) to (a2-r-7), Groups each represented by general formulas (a5-r-1) to (a5-r-4) and groups each represented by general formulas (ax3-r-1) to (ax3-r-3) are preferably mentioned.

Among them, a lactone-containing cyclic group or an -SO ₂ -containing cyclic group is preferable, and the general formula (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 Each group represented by -6-1), (r-sl-1-1), and (r-sl-1-18) is more preferable.

The structural unit (a2) of the component (A1) may be one or two or more.

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

If the ratio of the structural unit (a2) is more than the preferred lower limit, the effect of containing the structural unit (a2) is sufficiently obtained due to the above-described effect, and if it is less than the upper limit, the balance with other structural units can be taken. , Various lithographic properties are improved.

Constituent unit (a3):

Component (A1) is a structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group in addition to the structural unit (a1) (except for those corresponding to the structural unit (a1) or the structural unit (a2)) It may be to have. When the component (A1) has the structural unit (a3), the hydrophilicity of the component (A) increases, 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 carboxyl group, and a hydroxyalkyl group in which a part of the hydrogen atom of the alkyl group is substituted with a fluorine atom, and a hydroxyl group is particularly preferable.

Examples of the aliphatic hydrocarbon group include a C1-C10 linear or branched hydrocarbon group (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group, and for example, in resins for resist compositions for ArF excimer lasers, it can be appropriately selected and used from among a number of proposed ones.

When the cyclic group is a monocyclic group, the number of carbon atoms is more preferably 3 to 10. Among them, a structural unit derived from an acrylic acid ester containing an aliphatic monocyclic group containing a hydroxyalkyl group in which a hydroxyl group, a cyano group, a carboxyl group, or a part of the hydrogen atom of the alkyl group is substituted with a fluorine atom is more preferable. As the monocyclic group, a group excluding two or more hydrogen atoms from a monocycloalkane can be exemplified. Specifically, groups in which two or more hydrogen atoms have been removed from monocycloalkane such as cyclopentane, cyclohexane, and cyclooctane may be mentioned. Among these monocyclic groups, groups excluding two or more hydrogen atoms from cyclopentane and a group excluding 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 an aliphatic polycyclic group containing a hydroxyalkyl group in which a hydroxyl group, a cyano group, a carboxyl group, or a part of the hydrogen atom of the alkyl group is substituted with a fluorine atom is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms are removed from bicycloalkane, tricycloalkane, tetracycloalkane, and the like. Specifically, groups excluding two or more hydrogen atoms from polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane may be mentioned. Among these polycyclic groups, groups excluding two or more hydrogen atoms from adamantane, groups excluding two or more hydrogen atoms from norbornane, and groups excluding 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.

As the structural unit (a3), 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 is preferably a structural unit 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 hydroxyethyl ester of acrylic acid is preferable.

In addition, as the structural unit (a3), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a polycyclic group, the structural unit represented by the following formula (a3-1), the structural unit represented by the formula (a3-2), and the formula The structural unit represented by (a3-3) can be mentioned as a preferable thing; When it is a monocyclic group, a structural unit represented by formula (a3-4) is mentioned as a preferable thing.

[Chemical Formula 39]

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

In formula (a3-1), it is preferable that j is 1 or 2, and it is more preferable that it is 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group. It is preferable that j is 1, and it is particularly preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.

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

In formula (a3-3), it is preferable that t'is 1. It is preferable that l is 1. It is preferable that s is 1. It is preferable that these have a 2-norbornyl group or 3-norbornyl group bonded to the terminal of the carboxyl group of acrylic acid. It is preferable that the fluorinated alkyl alcohol is bonded to the 5 or 6 position of the norbornyl group.

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

The structural unit (a3) of the component (A1) may be one or two or more.

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

By making the ratio of the structural unit (a3) more than the preferred lower limit, the effect of containing the structural unit (a3) is sufficiently obtained by the above-described effect, and if it is less than or equal to the preferred upper limit, it is possible to balance with other structural units. Thereby, various lithographic properties are improved.

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 the component (A) becomes high. The improvement in hydrophobicity contributes to improvement in resolution, resist pattern shape, and the like, especially in the case of a solvent developing process.

The "acid non-dissociable cyclic group" in the structural unit (a4) is when an acid is generated in the resist composition by exposure (e.g., an acid is generated from the structural unit or component (B) that generates an acid by exposure). At the time), it is a cyclic group that does not dissociate even if the acid acts, and remains in the structural unit as it is.

As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing an acid non-dissociable aliphatic cyclic group, and the like are preferable. The cyclic group is used for a resin component of a resist composition such as an ArF excimer laser or a KrF excimer laser (preferably for an ArF excimer laser), and many conventionally known ones can be used.

The cyclic group is particularly preferably at least one selected from 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.

As the structural unit (a4), the structural units each represented by the following general formulas (a4-1) to (a4-7) can be illustrated.

[Formula 40]

[In the formula, R ^α is the same as above.]

The structural unit (a4) of the component (A1) may be one or two or more.

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 the 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 the structural unit (a4) more than the preferable lower limit, the effect of containing the constitutional unit (a4) is sufficiently obtained, and on the other hand, by making it less than or equal to the preferable upper limit, it becomes easy to balance with other constitutional units.

About the constituent unit (st):

The structural unit (st) is a structural unit derived from styrene or a styrene derivative. The "constituent unit derived from styrene" means a structural unit constituted by cleavage of an ethylenic double bond of styrene. The "constituent unit derived from a styrene derivative" means a structural unit constituted by cleavage of the ethylenic double bond of the styrene derivative (however, except for the structural unit (a10)).

The "styrene derivative" means a compound in which at least a part of hydrogen atoms of styrene is substituted with a substituent. Examples of styrene derivatives include those in which a hydrogen atom at the α-position of styrene is substituted with a substituent, at least one hydrogen atom in the benzene ring of styrene is substituted with a substituent, a hydrogen atom at the α-position of styrene, and 1 of the benzene ring. And those 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 the C1-C5 alkyl group, a C1-C5 linear or branched alkyl group is preferable, and specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl Group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like.

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. As the halogen atom, a fluorine atom is particularly preferable.

As the substituent for substituting the hydrogen atom at the α-position of styrene, a C1-C5 alkyl group or a C1-C5 fluorinated alkyl group is preferable, and a C1-C3 alkyl group or a C1-C3 fluorinated alkyl group is more preferable. In view of the industrial availability, a methyl group is more preferable.

Examples of the substituent for substituting the hydrogen atom of the benzene ring of styrene include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group.

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

As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and methoxy The timing and ethoxy group are more preferable.

The halogen atom as the substituent is preferably a fluorine atom.

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 atom.

As the substituent for substituting the hydrogen atom of the benzene ring of styrene, an alkyl group having 1 to 5 carbon atoms is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is still more preferable.

As the structural unit (st), 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 is preferable, A structural unit derived from styrene or a structural unit derived from a styrene derivative in which a hydrogen atom at the α-position of styrene is substituted with a methyl group is more preferable, and a constitutional unit derived from styrene is still more preferable.

The structural unit (st) of the component (A1) may be one or two or more.

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 the 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 singly 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), a polymer compound which has a repeating structure of a structural unit (a1) and a structural unit (a10) is mentioned.

In this case, the proportion of the structural unit (a1) in the polymer compound is preferably 5 to 80 mol%, and 10 to 75 mol% with respect to the total (100 mol%) of all the structural units constituting the polymer compound. It is more preferable, 30-70 mol% is still more preferable, and 40-60 mol% is especially preferable.

In addition, the proportion of the structural unit (a10) in the polymer compound is preferably 5 to 80 mol%, more preferably 10 to 75 mol% with respect to the total (100 mol%) of all the structural units constituting the polymer compound. It is preferable, and 30-70 mol% is more preferable, and 40-60 mol% is especially preferable.

The molar ratio of the structural unit (a1) and the structural unit (a10) in the polymer compound (constituent unit (a1): structural unit (a10)) is preferably from 2:8 to 8:2, and from 3:7 to It is more preferable that it is 7:3, and it is still more preferable that it is 4:6-6.

In the component (A1), a monomer that induces each structural unit is dissolved in a polymerization solvent, and for example, azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (for example, V-601, etc. ) Can be prepared by polymerization by adding a radical polymerization initiator such as).

Alternatively, the component (A1) is prepared by dissolving a monomer that induces the structural unit (a1) and, if necessary, a monomer that induces a structural unit other than the structural unit (a1) in a polymerization solvent, It can be produced by adding a polymerization initiator to polymerize, and then performing a deprotection reaction.

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

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

When the Mw of the component (A1) is less than or equal to the preferred upper limit of this range, there is sufficient solubility in a resist solvent to be used as a resist, and if it is greater than or equal to the preferred lower limit of this range, the dry etching resistance and the cross-sectional shape of the resist pattern are good.

The degree of dispersion (Mw/Mn) of the component (A1) is not particularly limited, and is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.0 to 2.0. In addition, Mn represents a number average molecular weight.

・(A2) ingredient

The resist composition of the present embodiment is a component (A), which does not correspond to the component (A1), but is a base component whose solubility in a developer is changed by the action of an acid (hereinafter referred to as "component (A2)"). You may use together.

The component (A2) is not particularly limited, and may be arbitrarily selected and used from a number of conventionally known base components for chemically amplified resist compositions.

As the component (A2), one type of a high molecular compound or a low molecular compound may be used alone, or two or more types may be used in combination.

The proportion of the component (A1) in the component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 75% by mass or more, and 100 with respect to the total mass of the component (A). It may be mass%. When the ratio is 25% by mass or more, it becomes easy to form a resist pattern excellent in various lithographic properties such as high sensitivity, resolution, and roughness improvement.

In the resist composition of the present embodiment, the content of the component (A) may be adjusted according to the thickness of the resist film to be formed.

<Onium salt-based acid generator component (B)>

In the resist composition of the present embodiment, the component (B) is not particularly limited, and includes onium salt-based acid generators such as iodonium salt and sulfonium salt that have been proposed as acid generators for chemically amplified resist compositions so far. I can.

As the component (B), 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, " (B-2) is also referred to as "component") or a compound represented by general formula (b-3) (hereinafter, also referred to as "(b-3) component").

[Formula 41]

[In the formula, 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 connecting group or a single bond containing an oxygen atom. Each of V ¹⁰¹ to V ¹⁰³ is 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.]

{Noon 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. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Moreover, the aliphatic hydrocarbon group may be saturated or unsaturated, and it is preferable that it is usually saturated.

The aromatic hydrocarbon group for R ¹⁰¹ is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, still more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent.

As ^{the aromatic ring which the aromatic hydrocarbon group for R 101} has, specifically, benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocycle in which a part of the carbon atoms constituting these aromatic rings is substituted with a hetero atom. And the like. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.

As ^{the aromatic hydrocarbon group for R 101} , specifically, a group excluding one hydrogen atom from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), and one of the hydrogen atoms of the aromatic ring is alkylene A group substituted with a group (for example, 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, etc.) etc. are mentioned. The number of carbon atoms in the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The cyclic aliphatic hydrocarbon group for R ¹⁰¹ includes an aliphatic hydrocarbon group containing a ring in the structure.

As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group excluding one hydrogen atom 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 And groups in which the alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group excluding one or more hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group excluding one or more hydrogen atoms from the polycycloalkane, and the polycycloalkane is preferably a C7 to C30 one. Among them, examples of the polycycloalkane include polycycloalkane having a crosslinked polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; A polycycloalkane having a condensed cyclic polycyclic skeleton 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 excluding one or more hydrogen atoms from a monocycloalkane or a polycycloalkane, more preferably a group excluding one hydrogen atom from a polycycloalkane, An adamantyl group and a norbornyl group are particularly preferred, and an adamantyl group is most preferred.

The linear aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, still more preferably 1 to 4, and most preferably 1 to 3. 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 -], and 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 which may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6, still more preferably 3 or 4, and most preferably 3. The branched-chain aliphatic hydrocarbon group is preferably a branched-chain alkylene group, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkyl methylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -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; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as an alkyl tetramethylene group, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -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 hetero ring or the like. Specifically, lactone-containing cyclic groups each represented by the above general formulas (a2-r-1) to (a2-r-7), respectively, by the above general formulas (a5-r-1) to (a5-r-4) The represented -SO ₂ -containing cyclic group, and other heterocyclic groups each represented by the following formulas (r-hr-1) to (r-hr-16) are exemplified. In the formula, * represents a bond hand bonded to ^{Y 101} in formula (b-1).

[Formula 42]

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, a nitro group, and the like. As an alkyl group as a substituent, a C1-C5 alkyl group is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are most preferable.

As the alkoxy group as a substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and a methoxy group And an ethoxy group are most preferable.

As the halogen atom as a substituent, a fluorine atom is preferable.

Examples of the halogenated alkyl group as a substituent include a group in which a part or all of the hydrogen atoms such as a C1-C5 alkyl group, for example a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are substituted with the halogen atom. have.

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

The cyclic hydrocarbon group for R ¹⁰¹ may be a condensed cyclic group including a condensed ring in which an aliphatic hydrocarbon ring and an aromatic ring are condensed. Examples of the condensed ring include those in which one or more aromatic rings are condensed with a polycycloalkane having a polycyclic skeleton of a bridged ring system. Specific examples of the crosslinked cyclic polycycloalkane include bicycloalkane such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. As the condensed cyclic type, a group including a condensed ring in which two or three aromatic rings are condensed with a bicycloalkane is preferable, and a condensed group in which two or three aromatic rings are condensed with a bicyclo[2.2.2]octane is condensed. Groups containing a ring are more preferred. As ^{a specific example of the condensed cyclic group for R 101} , groups represented by the following formulas (r-br-1) to (r-br-2) are exemplified. In the formula, * represents a bond hand bonded to ^{Y 101} in formula (b-1).

[Formula 43]

Examples of the substituent that the condensed cyclic group for R ¹⁰¹ may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an aromatic hydrocarbon group, an alicyclic hydrocarbon group, and the like. have.

Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the condensed cyclic group are the same as those mentioned as the substituent of the cyclic group in ^{R 101.}

As the aromatic hydrocarbon group as a substituent of the condensed cyclic group, a group excluding one hydrogen atom from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), and one of the hydrogen atoms of the aromatic ring is substituted with an alkylene group. Group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group), the above formula (r-hr- The heterocyclic groups each represented by 1)-(r-hr-6), etc. are mentioned.

Examples of the alicyclic hydrocarbon group as a substituent of the condensed cyclic group include groups excluding one hydrogen atom from monocycloalkane such as cyclopentane and cyclohexane; A group excluding one hydrogen atom from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; 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 general formulas (a5-r-1) to (a5-r-4); Heterocyclic groups each represented by the above formulas (r-hr-7) to (r-hr-16), etc. are mentioned.

Chain-type alkyl group which may have a substituent:

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

As a linear alkyl group, it is preferable that it is C1-C20, it is more preferable that it is 1-15, and 1-10 are most preferable.

As a branched chain alkyl group, it is preferable that it has 3-20 carbon atoms, it is more preferable that it is 3-15, and 3-10 are 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, and the like.

Chain alkenyl group which may have a substituent:

The chain alkenyl group of R ¹⁰¹ may be linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5, and 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. Examples of the branched chain alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.

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 group or alkenyl group of 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 in ^{R 101.} I 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 excluding one or more hydrogen atoms 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 general formulas (a5-r-1) to (a5-r-4) are preferable.

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

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

As a divalent linking group containing an oxygen atom, for example, 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-), etc. ; The combination of the non-hydrogen-based oxygen atom-containing linking group and an alkylene group may be mentioned. A sulfonyl group (-SO ₂ -) may be further linked to this combination. As a divalent linking group containing such an oxygen atom, the linking groups respectively represented by the following general formulas (y-al-1)-(y-al-7) are mentioned, for example.

[Formula 44]

[In the formula, ^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.]

The divalent saturated hydrocarbon group for V′ ¹⁰² is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and still more preferably an alkylene group having 1 to 5 carbon atoms.

V alkylene group in the ^'101 and V' is ^102, and the contribution of the linear alkylene is alkylene contribution of the branched, is preferably an alkylene group of a linear.

V Specifically, a methylene group [-CH ₂ -] as an alkylene group in the ^"101 and V"^102; -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ Alkyl methylene groups, such as CH ₂ CH ₃ )- and -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 -]; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Tetramethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ -]; Alkyl tetramethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH ₂ CH _{2 -;} And 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 further excludes one hydrogen atom from the cyclic aliphatic hydrocarbon group of Ra' 3} in the formula (a1-r-1) (a monocyclic aliphatic hydrocarbon group, a polycyclic aliphatic hydrocarbon group). 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 the linking groups each represented by the formulas (y-al-1) to (y-al-5) are more preferable. Do.

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. It is preferable that the alkylene group and the fluorinated alkylene group for V ^{101 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. Especially, ^{it is preferable that V 101} is a single bond or a C1-C4 fluorinated alkylene group.

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 R ¹⁰² is a fluorine atom or a C1-C5 perfluoroalkyl group, and it is more preferable that it is a fluorine atom.

As a specific example of the anion moiety represented by the above formula (b-1), for example, when Y ¹⁰¹ becomes a single bond, fluorination of trifluoromethanesulfonate anion or perfluorobutanesulfonate anion, etc. An alkyl sulfonate 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 45]

[In the formula, 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), and the above formula (r- br-1) A condensed cyclic group further represented by (r-br-2) or a chain alkyl group which ^{may have a substituent. R" 102} is an aliphatic cyclic group which may have a substituent, the formula (r-br -1) Condensed cyclic group further represented by (r-br-2), lactone-containing cyclic group each represented by the general formulas (a2-r-1), (a2-r-3) to (a2-r-7) _{Or they are -SO 2} -containing cyclic groups respectively represented by the said general formula (a5-r-1)-(a5-r-4). R" ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent. V" ¹⁰¹ is a single bond and an alkyl having 1 to 4 carbon atoms. It is a ene group or a C1-C4 fluorinated alkylene group. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. v" is each independently an integer of 0 to 3, q" is each independently an integer of 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 a 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 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 for R" ¹⁰³ is preferably a group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group for ^{R 101 in the formula (b-1).} Is the same as the substituent which may substitute the aromatic hydrocarbon group ^{in R 101} in the formula (b-1).

The chain alkyl group which may have a substituent for R" ¹⁰¹ is preferably a 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 a 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, Respectively, the same thing as ^{R 101} in Formula (b-1) is mentioned. However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.

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

The number of carbon atoms of the chain alkyl group is preferably 1 to 10, more preferably 1 to 7, more preferably 1 to 3 carbon atoms. The number of carbon atoms in the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably in the range of the above-described carbon number for reasons such as good solubility in a solvent for resists. In addition, in ^{the chain alkyl group of R 104} and R ^105, the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and the greater the transparency to high-energy light or electron beams of 250 nm or less. That's why it is desirable. 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 those ^{of V 101 in the formula (b-1) can be exemplified.}

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, Respectively, the same thing as ^{R 101} in Formula (b-1) is mentioned.

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

Among the above, as the anion moiety of the component (B), the anion in the component (b-1) is preferable. Among these, the anions represented by any of the general formulas (an-1) to (an-3) are more preferable, and the anions represented by any of the general formulas (an-1) or (an-2) are more It is preferable, and the anion represented by general formula (an-2) is particularly preferable.

{Cation Department}

In the above formulas (b-1), (b-2), and (b-3), ^M'm+ represents an m-valent onium cation. 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 ), the organic cation represented respectively by following general formulas (ca-1)-(ca-5) is mentioned.

[Formula 46]

[In the formula, R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² each independently represent an aryl group, an alkyl group, or an alkenyl group which may have a substituent. 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 ~ R ²⁰⁹ each independently represents 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 an SO ₂ -containing cyclic group which may have a substituent. L ²⁰¹ represents -C(=O)- or -C(=O)-O-. Each of Y ²⁰¹ 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.]

In the above general formulas (ca-1) to (ca-5), examples ^{of the aryl group for R 201} to R ²⁰⁷ and R ²¹¹ to R ²¹² 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 a chain or cyclic alkyl group, preferably having 1 to 30 carbon atoms.

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

Examples of the substituents R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have include, for example, 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 The groups represented by -1)-(ca-r-7) respectively, etc. are mentioned.

[Chemical Formula 47]

[In the formula, ^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. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Moreover, the aliphatic hydrocarbon group may be saturated or unsaturated, and it is preferable that it is usually saturated.

R 'group is an aromatic hydrocarbon in the ^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, the number of carbon atoms does not include the number of carbon atoms in the substituent.

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

R 'group as the aromatic hydrocarbon group in the ²⁰¹ Specifically, other than a hydrogen atom from the aromatic ring (aryl, for example in a phenyl group, a naphthyl group, etc.), have one of the hydrogen atoms of the aromatic ring-alkylene A group substituted with a group (for example, 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, etc.), etc. are mentioned. The number of carbon atoms of the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1 to 2 carbon atoms.

R 'groups are aliphatic hydrocarbon cyclic in ^201, there may be mentioned an aliphatic hydrocarbon group containing a ring in the structure.

As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group excluding one hydrogen atom 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 And groups in which the alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group excluding one or more hydrogen atoms from a monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group excluding one or more hydrogen atoms from the polycycloalkane, and the polycycloalkane is preferably a C7 to C30 one. Among them, examples of the polycycloalkane include polycycloalkane having a crosslinked polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; A polycycloalkane having a condensed cyclic polycyclic skeleton 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 and a norbornyl group are 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, even more preferably 1 to 4 carbon atoms, and 1 -3 is particularly 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 -], and 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, and specifically, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, Alkyl methylene groups, such as -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -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; Alkyl trimethylene groups, such as -CH(CH ₃ )CH ₂ CH ₂ -and -CH ₂ CH(CH ₃ )CH _{2 -;} Alkylalkylene groups, such as an alkyl tetramethylene group, such as -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -and -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, lactone-containing cyclic groups each represented by the above general formulas (a2-r-1) to (a2-r-7), respectively, by the above general formulas (a5-r-1) to (a5-r-4) The represented -SO ₂ -containing cyclic group, and other heterocyclic groups each represented by the above formulas (r-hr-1) to (r-hr-16) are exemplified.

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, a nitro group, and the like.

As an alkyl group as a substituent, a C1-C5 alkyl group is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are most preferable.

As the alkoxy group as a substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and a methoxy group And an ethoxy group are most preferable.

As the halogen atom as a substituent, a fluorine atom is preferable.

Examples of the halogenated alkyl group as a substituent include a group in which a part or all of the hydrogen atoms such as a C1-C5 alkyl group, for example a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are substituted with the halogen atom. have.

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

Chain-type alkyl group which may have a substituent:

The alkyl group of the R 'chain of the type ²⁰¹ are, and 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.

The branched-chain alkyl group is preferably 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, and the like.

Chain alkenyl group which may have a substituent:

R alkenyl "al-chain of the ^201-type groups include, may be any of linear or branched, having a carbon number of 2 to 10 is preferable, and carbon atoms and 2 to 5 are more preferable, a carbon number of 2-4 is more It is preferred, and 3 carbon atoms are particularly preferred. As a linear alkenyl group, a vinyl group, a propenyl group (allyl group), a butynyl group, etc. are mentioned, for example. Examples of the branched chain alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.

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 group or alkenyl group of 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, and the cyclic group in ^{R′ 201.} Can be mentioned.

A cyclic group which may have a substituent for R′ ²⁰¹ , a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent is a cyclic group or substituent which may have a substituent in addition to those described above. As the chain-type alkyl group which may have, the same as the acid dissociable group represented by the above-described formula (a1-r-2) can be mentioned.

In particular, R ^'201 is preferably a cyclic group which may have a substituent, more preferably a hydrocarbon group of the type rings have a substituent. More specifically, for example, a group excluding one or more hydrogen atoms 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 general formulas (a5-r-1) to (a5-r-4) are preferable.

In the above general formulas (ca-1) to (ca-5), ^{as the substituent which R 201} to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have, among the above, it is preferable that it is an electron withdrawing group. One type may be sufficient as the electron withdrawing group, and two or more types may be sufficient as it.

The electron withdrawing group may be, for example, an electron withdrawing group of a monovalent substituent or an electron withdrawing group of a divalent substituent. Specifically, an acyl group, a methanesulfonyl group (mesyl group), a halogen atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated aryloxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group , A diarylphosphono group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, and a thiocarbonyl group.

Among the above, a fluorine atom, a fluorinated alkyl group, or a sulfonyl group is preferable from the viewpoint of high sensitivity. The fluorinated alkyl group is preferably a fluorinated alkyl group having 1 to 5 carbon atoms.

When the electron withdrawing group is a fluorine atom or a fluorinated alkyl group, the number of fluorine atoms in the cation portion of the component (B) is preferably 1 to 9, more preferably 2 to 7, and furthermore 3 to 7 desirable.

The greater the number of fluorine atoms, the better the sensitivity, but if it is less than or equal to the upper limit of the preferred range, the solubility in the developer with each component of the resist composition is maintained, and deterioration of roughness is easily suppressed.

In the above general formulas (ca-1) to (ca-5), when 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 hetero atom such as a sulfur atom, an oxygen atom, or a nitrogen atom, or 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 bond through functional groups, such as. As the ring to be formed, it is preferable that one ring containing a sulfur atom in the formula in its ring skeleton is a 3 to 10 membered ring including a sulfur atom, and particularly preferably a 5 to 7 membered ring. Specific examples of the ring to be formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, dibenzothiophene ring, 9H-thioxanthene ring, thioxanthone ring, thianthrene ring, phenoxati A phosphorus ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring, etc. are mentioned.

Each of R ²⁰⁸ to R ²⁰⁹ independently represents 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 may be bonded to 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 an 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 a chain or cyclic alkyl group, preferably having 1 to 30 carbon atoms.

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

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

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

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

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

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

As the ^{divalent linking group in W 201} , a divalent hydrocarbon group which may have a substituent is preferable, and the same divalent hydrocarbon group which may have a substituent as ^{Ya 21 in the above-described general formula (a2-1) is exemplified.} I can. The ^{divalent linking group in 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. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly 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. As the ^{trivalent linking group for W 201} , a group in which two carbonyl groups are bonded to an arylene group is preferable.

Preferred cation represented by said formula (ca-1) is shown below.

[Formula 48]

[Formula 49]

[Formula 50]

[In the formula, g1, g2, g3 represents the number of repetitions, g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20.]

[Formula 51]

[Formula 52]

[Chemical Formula 53]

[Chemical Formula 54]

[Chemical Formula 55]

[In the formula, R" ²⁰¹ is a hydrogen atom or a substituent, and the substituent is the same as the substituent which R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have.]

[Chemical Formula 56]

[Chemical Formula 57]

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

Specific examples of preferable cation represented by the above formula (ca-3) include cation represented by the following formulas (ca-3-1) to (ca-3-6).

[Chemical Formula 58]

Specific examples of preferable cation represented by the above formula (ca-4) include cation represented by the following formulas (ca-4-1) to (ca-4-2).

[Chemical Formula 59]

Specific examples of preferred cation represented by the above formula (ca-5) include cation represented by the following general formulas (ca-5-1) to (ca-5-3).

[Chemical Formula 60]

In the resist composition of the present embodiment, the cation moiety of the component (B) is an organic cation having an electron withdrawing group in any of the organic cation represented by the general formulas (ca-1) to (ca-5), respectively. It is desirable.

When the electron withdrawing group is a fluorine atom or a fluorinated alkyl group, the number of fluorine atoms in the cation portion of the component (B) is preferably 1 to 9, more preferably 2 to 7, and furthermore 3 to 7 desirable.

The greater the number of fluorine atoms, the better the sensitivity, but if it is less than or equal to the upper limit of the preferable range, the solubility in the developer is maintained, and the deterioration of roughness is easily suppressed.

In the resist composition of the present embodiment, the cation moiety of the component (B) is preferably a cation represented by the general formula (ca-1) having an electron withdrawing group. Among them, the above formulas (ca-1-43) to (ca-1-45), (ca-1-70) to (ca-1-84), (ca-1-118) to (ca-1 The cation represented by any of -120) is preferable, and the above formulas (ca-1-72), (ca-1-73), (ca-1-78), (ca-1-118) to (ca The cation represented by any one of -1-120) is more preferable.

In the resist composition of the present embodiment, the component (B) is preferably a compound represented by the following general formula (b-1-1) (hereinafter also referred to as "component (b-1-1)"). .

[Chemical Formula 61]

[In the formula, R ^b1 is an aryl group having an electron withdrawing group. R ^b2 and R ^b3 are each independently an aryl group which may have a substituent, or 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 connecting group or a single bond containing an oxygen atom. V ¹⁰¹ is a single bond or an oxygen atom.]

{Anion in the component (b-1-1)}

The anion in the component (b-1-1) is the same as the anion in the component (b-1) described above.

{(b-1-1) cation in component}

R ^b1 is an aryl group having an electron withdrawing group. R ^b2 and R ^b3 are each independently an aryl group which may have a substituent, or combine with each other to form a ring together with the sulfur atom in the formula. The aryl group in R ^b1 to R ^b3 is the same as the aryl group in ^{R 201} to R ²⁰³ in the formula (ca-1). The substituent which the aryl group in R ^b2 and R ^b3 may have is the same as the substituent which the aryl group in R ²⁰¹ to R ²⁰³ in the formula (ca-1) may have.

R ^b2 and R ^b3 are bonded to each other to form a ring together with a sulfur atom in the formula, wherein R ²⁰¹ to R ^{203 in} the formula (ca-1) are the same as the ring formed together with the sulfur atom in the formula (ca-1). Can be mentioned.

Specific examples of the component (B) will be given below, but it is not limited to these.

[Formula 62]

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 the component (B), in the resist composition, the content of the component (B) is preferably less than 50 parts by mass, more preferably 1 to 40 parts by mass, based on 100 parts by mass of the component (A). , 5 to 25 parts by mass is more preferable.

By making the content of the component (B) within the above-described preferable range, the solubility of the developer can be properly secured, so that the effects of the present invention are more easily obtained.

<Compound (D0)>

In the resist composition of the present embodiment, the component (D0) is a compound composed of an anion moiety and a cation moiety represented by the following general formula (d0).

[Chemical Formula 63]

[In the formula, M ^m+ represents an m-valent organic cation. m is an integer of 1 or more. R ^d0 is a substituent. p is an integer of 0-2. When p is 2, ^{a plurality of substituents in R d0} may be the same or different. q is an integer of 0-3. n is an integer of 2 or more. However, it is n + p ≤ (q × 2) + 5.]

{Noon part}

In formula (d0), R ^d0 is a substituent. Examples of the substituent include a hydrocarbon group, an alkoxy group, an acyl group, and a hydroxyalkyl group.

As a hydrocarbon group as a substituent, a linear or branched alkyl group, an aliphatic cyclic hydrocarbon group, an aromatic hydrocarbon group, etc. are mentioned.

As the linear or branched alkyl group, a linear or branched alkyl group having 1 to 5 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group And a pentyl group.

The aliphatic cyclic hydrocarbon group is preferably an aliphatic cyclic hydrocarbon group having 3 to 6 carbon atoms, and specifically, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group are exemplified.

As the aromatic hydrocarbon group, an aromatic hydrocarbon group having 6 to 30 carbon atoms is preferable, and specifically, a group in which one hydrogen atom is removed from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene. . Especially, the group (phenyl group) which removed one hydrogen atom from benzene is more preferable.

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, and specifically, a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, a tert-butoxy group, a pentyloxy group, and the like. Among them, a methoxy group is more preferable.

The acyl group as a substituent is preferably an acyl group having 1 to 3 carbon atoms, and specifically, a formyl group, an acetyl group, and a propionyl group are exemplified.

The hydroxyalkyl group as a substituent is preferably a C1-C5 hydroxyalkyl group, and specifically, a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a hydroxypentyl group, etc. are mentioned. .

In formula (d0), p is an integer of 0 to 2, and when p is 2, ^{the substituents in a plurality of R d0} may be the same or different. Especially, 0 or 1 is preferable and, as for p, 0 is more preferable.

In formula (d0), n is an integer of 2 or more. Especially, 2 or 3 is preferable and, as for n, 2 is more preferable.

In formula (d0), q is an integer of 0-3. That is, in the anionic moiety in the formula (d0), when q is 0, a benzene structure, when q is 1, a naphthalene structure, when q is 2, an anthracene structure, and when q is 3, tetra It becomes a strong structure.

Moreover, it is n+p≦(q×2)+5. That is, in the benzene structure, naphthalene structure, anthracene structure, and tetracene structure, all hydrogen atoms other than the hydrogen atom substituted with a carboxylate group may be respectively substituted with the above substituents or hydroxy groups. However, the anionic moiety in formula (d0) has at least two hydroxy groups.

Below, preferable specific examples of the anionic moiety in the component (D0) are shown.

[Formula 64]

[Formula 65]

[Formula 66]

[Chemical Formula 67]

[Chemical Formula 68]

[Chemical Formula 69]

The anion moiety in the component (D0) is more preferably an anion represented by any of the formulas (an-d0-1) to (an-d0-27), among the above examples, and the formula (an-d0-2) The anion represented by any of to (an-d0-4) is more preferable.

{Cation Department}

In the formula (d0), M ^m+ represents an m-valent organic cation. m is an integer of 1 or more.

As the organic cation, those similar to the cation represented by the general formulas (ca-1) to (ca-5), respectively, are preferably exemplified. Among the above, a cation represented by the general formula (ca-1) having an electron withdrawing group is preferable.

When the electron withdrawing group is a fluorine atom or a fluorinated alkyl group, the number of fluorine atoms in the cation portion of the component (D0) is preferably 1 to 9, more preferably 2 to 7, and furthermore 3 to 7 desirable.

The greater the number of fluorine atoms, the better the sensitivity, but if it is less than or equal to the upper limit of the preferred range, the solubility in the developer with each component of the resist composition is maintained, and deterioration of roughness is easily suppressed.

As the organic cation, among the above, the above formulas (ca-1-43) to (ca-1-45), (ca-1-70) to (ca-1-84), (ca-1- A cation represented by any of 118) to (ca-1-120) is preferable, and the above formulas (ca-1-72), (ca-1-73), (ca-1-78), and (ca- The cation represented by any one of 1-118)-(ca-1-120) is more preferable.

In the resist composition of the present embodiment, the component (D0) is preferably a compound composed of an anion moiety and a cation moiety (hereinafter also referred to as “(D01) component”) represented by the following general formula (d0-1).

[Formula 70]

[In the formula, R ^d1 is an aryl group having an electron withdrawing group. R ^d2 and R ^d3 are each independently an aryl group which may have a substituent, or combine with each other to form a ring together with the sulfur atom in the formula. R ^d0 is a substituent. p is an integer of 0-3. When p is 2 or 3, a plurality of R ^d0 may be the same or different. q is an integer of 0-3. n is an integer of 2 or more. However, it is n + p ≤ (q × 2) + 5.]

The cation moiety in the component (D01) is the same as the cation moiety in the component (b-1-1) described above. The anion moiety in the component (D01) is the same as the anion moiety in the component (D0) described above.

Although specific examples of the component (D0) will be given below, it is not limited to these.

[Formula 71]

[Formula 72]

In the resist composition of the present embodiment, the component (D0) may be used alone or in combination of two or more.

In the resist composition of the present embodiment, the content of the component (D0) is preferably 1 to 35 parts by mass, more preferably 2 to 25 parts by mass, and still more preferably 3 to 20 parts by mass per 100 parts by mass of the component (A). And 3 to 15 parts by mass is particularly preferred.

By making the content of the component (D0) within the above-described preferred range, the solubility of the developer can be properly secured, so that the effects of the present invention are more easily obtained.

In the resist composition of the present embodiment, at least one cation moiety of the component (B) and the component (D0) described above is a cation having an electron withdrawing group, and both the component (B) and the component (D0) described above It is preferably a cation having an electron withdrawing group.

More specifically, the resist composition of the present embodiment preferably contains the component (b-1-1) or the component (D01) described above, and the component (b-1-1) and the component (D01) described above are ) It is more preferable to contain the component.

In the resist composition of the present embodiment, as for the mixing ratio (mass ratio) of the component (B) and the component (D0) described above, the content of the component (B) / the content of the component (D0) is preferably 1.5 to 5, 2-4 are more preferable.

<Arbitrary Ingredients>

The resist composition of this embodiment may further contain components (arbitrary components) other than the above-described (A) component, (B) component, and (D0) component.

Examples of such an optional component include (D) component (except for the component (D0)), (E) component, (F) component, and (S) component shown below. have.

≪(D) component≫

The resist composition in this embodiment may further contain a base component (component (D)) other than the component (D0). The component (D) acts as an agent (acid diffusion control agent) that traps acid generated by exposure in the resist composition.

As the component (D), for example, a photodegradable base (D1) that loses acid diffusion controllability by decomposition by exposure not corresponding to the component (D0) (hereinafter referred to as "component (D1)"). , And the nitrogen-containing organic compound (D2) which does not correspond to the component (D0) and the component (D1) (hereinafter referred to as "component (D2)"), and the like.

By setting it as a resist composition containing the component (D), when forming a resist pattern, the contrast of the exposed part and the unexposed part of a resist film can be improved more.

・(D1) ingredient

The component (D1) does not correspond to the component (D0), and is not particularly limited as long as it decomposes by exposure to lose controllability of acid diffusion, and a compound represented by the following general formula (d1-1) (hereinafter “(d1-1 ), a compound represented by the following general formula (d1-2) (hereinafter referred to as a “(d1-2) component”), and a compound represented by the following general formula (d1-3) (hereinafter, “(d1 -3) Component". At least one compound selected from the group consisting of) is preferable.

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

[Chemical Formula 73]

[In the formula, 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. However, it is assumed that the fluorine atom is not bonded to the carbon atom adjacent to the S atom ^{in Rd 2} in the general formula (d1-2). 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 m-valent onium cation.]

{(d1-1) component}

·Anion Department

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, each of the formula (b-1) The ^{same thing as R 101 in} ) can be mentioned.

Among these, Rd ¹ is preferably 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. Examples of the substituents that 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 ring each represented by the aforementioned general formulas (a2-r-1) to (a2-r-7). A mold group, 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 the substituent in this case is preferably a linking group represented by the above formulas (y-al-1) to (y-al-5). Do.

As the aromatic hydrocarbon group, a polycyclic structure including a phenyl group, a naphthyl group, and a bicyclooctane skeleton (e.g., a polycyclic structure consisting of a ring structure of a bicyclooctane skeleton and a ring structure other than this) is preferably mentioned. I can.

The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from polycycloalkane 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 Branched-chain alkyl groups, such as a pentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group, are mentioned.

When the chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms of the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and still more preferably 1 to 4. The fluorinated alkyl group may contain atoms other than a fluorine atom. As an atom 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 a 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. It is particularly preferable that it is a (linear perfluoroalkyl group).

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

[Chemical Formula 74]

·Cation Department

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

As ^{the onium cation of M'm +} , the same cation as each represented by the general formulas (ca-1) to (ca-5) is preferably exemplified.

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

{(d1-2) component}

·Anion Department

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 the formula (b-1) The ^{same thing as R 101} and the like can be mentioned.

However, it is assumed that the fluorine atom is not bonded to the carbon atom adjacent to the S atom in ^{Rd 2 (which is not substituted with fluorine).} Thereby, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the performance of the quenching as the component (D1) is improved.

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 alkyl group, it is preferable that it is C1-C10, and it is more preferable that it is 3-10. As an aliphatic cyclic group, a group excluding one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (You may have a substituent); It is more preferable that one or more hydrogen atoms are removed from camphor or the like.

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

A preferred specific example of the anionic moiety of the component (d1-2) is shown below.

[Chemical Formula 75]

·Cation Department

In formula (d1-2), M'm ⁺ is an m-valent onium cation, and it is the same as ^{M'm+ in said formula (d1-1).}

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

{(d1-3) component}

·Anion Department

In 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 in the above formula (b-1) The ^{same as R 101} and the like are mentioned, and a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group is preferable. Among these, a fluorinated alkyl group is preferable, and the same is more preferable as the fluorinated alkyl group of ^{Rd 1.}

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 the formula (b-1) The ^{same thing as R 101} and the like can be mentioned.

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

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. 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 as an alkoxy group having 1 to 5 carbon atoms, specifically, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Butoxy group and tert-butoxy group. Among them, a methoxy group and an ethoxy group are preferable.

Examples of the alkenyl group for Rd ^{4 include the same as R 101} in the above formula (b-1), and a vinyl group, a propenyl group (allyl group), 1-methylpropenyl group, and 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.

The cyclic group for Rd ^{4 includes the same as R 101} in the formula (b-1), and cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclo An alicyclic group excluding one or more hydrogen atoms from a cycloalkane such as dodecane, 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 is satisfactorily dissolved in an organic solvent, thereby improving lithography characteristics.

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

Although it does not specifically limit as a divalent linking group for 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. These are the same as the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom in the description of the divalent linking group ^{in Ya x1 in the formula (a10-1), respectively.}

Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. As the 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.

A preferred specific example of the anion moiety of the component (d1-3) is shown below.

[Chemical Formula 76]

[Chemical Formula 77]

·Cation Department

In formula (d1-3), M'm ⁺ is an m-valent onium cation, and it is the same as ^{M'm+ in said formula (d1-1).}

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

As the component (D1), only one of the components (d1-1) to (d1-3) may be used, or two or more types may be used in combination.

When the resist composition contains the component (D1), in the resist composition, the content of the component (D1) is preferably 0.5 to 35 parts by mass, more preferably 1 to 25 parts by mass, based on 100 parts by mass of the component (A). , 2 to 20 parts by mass is more preferable, and 3 to 15 parts by mass is particularly preferable.

When the content of the component (D1) is more than a preferable lower limit, particularly favorable lithography properties and resist pattern shape are easily obtained. On the other hand, if it is less than the upper limit, balance with other components can be obtained, and various lithography characteristics become favorable.

(D1) Method of manufacturing component:

The method for producing the component (d1-1) and the component (d1-2) is not particularly limited, and can be produced by a known method.

In addition, the manufacturing method of the component (d1-3) is not particularly limited, and is manufactured, for example, in the same manner as the method described in US2012-0149916.

・(D2) Ingredient

The component (D2) is a nitrogen-containing organic compound that acts as an acid diffusion control agent in the resist composition as a base component.

The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not correspond to the component (D0) and the component (D1), and examples thereof include aliphatic amines and aromatic amines. have.

The aliphatic amine is preferably a secondary aliphatic amine or a tertiary aliphatic amine.

The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.

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

Specific examples of the alkylamine and the alkyl alcohol amine 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; Alkyl alcohol amines, such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine, are mentioned. Among these, trialkylamines having 5 to 10 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

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

Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. 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, and the like.

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.

Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, aniline compounds, and N-tert-butoxycarbonylpyrrolidine.

Component (D2) may be used individually by 1 type, and may be used in combination of 2 or more types. Among the above, the component (D2) is preferably an aromatic amine, and more preferably an aniline compound. Examples of the aniline compound include 2,6-diisopropylaniline, N,N-dimethylaniline, N,N-dibutylaniline, and N,N-dihexylaniline.

When the resist composition contains the component (D2), in the resist composition, the component (D2) is usually used in the range of 0.01 to 5 parts by mass per 100 parts by mass of the component (A). By setting it as the said range, balance with other components can be obtained, and various lithography characteristics become favorable.

≪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 this embodiment, for the purpose of preventing deterioration of sensitivity, improving the shape of the resist pattern, and stability over time after exposure, as an optional component, an organic carboxylic acid and phosphorus oxoic acid and derivatives thereof are formed. At least one compound (E) selected from the group (hereinafter referred to as "component (E)") can be contained.

As an 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 phosphorus oxo acid derivatives include esters in which a hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and 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 mentioned.

Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.

Phosphonic acid esters, such as a phosphonic acid dimethyl ester, a phosphonic acid-di-n-butyl ester, a phenylphosphonic acid, a phosphonic acid diphenyl ester, and a phosphonic acid dibenzyl ester, etc. are mentioned as a phosphonic acid derivative.

Phosphinic acid derivatives include phosphinic acid esters and phenylphosphinic acid.

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

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

(F) As a component, for example, JP 2010-002870 A, JP 2010-032994 A, JP 2010-277043 A, JP 2011-13569 A, JP The fluorinated polymer compound described in Publication No. 2011-128226 can be used.

More specifically, as the component (F), a polymer having a structural unit (f1) represented by the following general formula (f1-1) is exemplified. As this polymer, it is a polymer (homopolymer) which consists only of the structural unit (f1) represented by 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) Constituent units derived from acrylates are preferred.

[Chemical Formula 78]

[In the formula, 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 May or may be different. nf ¹ is an integer of 0 to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom.]

In 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 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 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 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. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. Among these, as Rf ¹⁰² and Rf ¹⁰³ , a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms 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 0-5, an integer of 0-3 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.

As the hydrocarbon group containing a fluorine atom, linear, branched or cyclic may be used, and the number of carbon atoms is preferably 1 to 20, more preferably 1 to 15, and 1 to 10 carbon atoms. It is particularly preferred.

In addition, the hydrocarbon group containing a fluorine atom preferably has 25% or more of the hydrogen atoms in the hydrocarbon group fluorinated, more preferably 50% or more is fluorinated, and 60% or more is fluorinated, It is particularly preferable from the viewpoint of increasing the hydrophobicity of the resist film during immersion exposure.

Among them, Rf ¹⁰¹ is more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, and a trifluoromethyl group, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH(CF ₃ ) ₂ ,- Particularly preferred are CH ₂ -CH ₂ -CF ₃ , -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF _3.

The weight average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography) of the component (F) is preferably from 1000 to 50000, more preferably from 5000 to 40000, and most preferably from 10000 to 30000. If it is less than the upper limit of this range, there is sufficient solubility in the solvent for resist 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 good.

The degree of dispersion (Mw/Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

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

When the resist composition contains the component (F), the content of the component (F) is usually used in a ratio of 0.5 to 10 parts by mass with respect to 100 parts by mass of the 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 may be appropriately selected and used from those known as solvents for chemically amplified resist compositions in the past, as long as each component to be used is dissolved and a uniform solution can be obtained.

Examples of the component (S) include lactones such as γ-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; Compounds 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 alcohols or compounds having the ester bond, Derivatives of polyhydric alcohols, such as monoalkyl ethers such as monopropyl ether and monobutyl ether, or compounds having an ether bond such as monophenyl ether [In particular, 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, ethylbenzyl ether, cresylmethyl ether, diphenyl ether, dibenzyl ether, phenethyl, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene Aromatic organic solvents such as dimethyl sulfoxide (DMSO), and the like.

In the resist composition of the present embodiment, the component (S) may be used alone or as a mixed solvent of two or more. Among them, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferable.

Further, as the component (S), a mixed solvent obtained by mixing PGMEA and a polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility of PGMEA and the polar solvent, but it is preferably in the range of 1:9 to 9:1, more preferably 2:8 to 8:2. desirable.

More specifically, in the case of blending EL or cyclohexanone as a polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9 to 9:1, more preferably 2:8 to 8: It is 2. In addition, in the case of blending PGME as a polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, still more preferably 3:7 to 7: 3. In addition, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferred.

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 the mixing ratio, the mass ratio of the former and the latter is preferably 70:30 to 95:5.

The amount of the component (S) to be used is not particularly limited, and is a concentration applicable to a substrate or the like, and is appropriately set according to the thickness of the coating film. In general, the component (S) is used so that the solid content concentration of the resist composition is in the range of 0.1 to 20% by mass, preferably 0.2 to 15% by mass.

In the resist composition of the present embodiment, as desired, additives with miscibility, for example, additional resins for improving the performance of the resist film, dissolution inhibitors, plasticizers, stabilizers, coloring agents, antihalation agents, dyes, etc. , Can be added and contained.

In the resist composition of the present embodiment, after dissolving the resist material in the component (S), a porous polyimide film, a porous polyamideimide film, or the like may be used to remove impurities and 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. Examples of the porous polyimide film and the porous polyamide-imide film include those described in Japanese Unexamined Patent Application Publication No. 2016-155121.

In the resist composition of the present embodiment described above, since at least one cation portion of the component (B) and the component (D0) is a cation having an electron withdrawing group, the reactivity is increased. In addition, since the anionic portion of the component (D0) has a plurality of hydroxy groups, the developer affinity is excellent, and the developer solubility in the exposed portion is improved. Therefore, the resist composition of the present embodiment can achieve both high sensitivity and lithography characteristics.

(Resist pattern formation method)

The resist pattern formation method of this embodiment is a step of forming a resist film on a support by using the resist composition of the above-described embodiment, a step of exposing the resist film, and developing the resist film after the exposure to form a resist pattern. It is a method of having a process of doing.

As an embodiment of such a resist pattern formation method, a resist pattern formation method performed as follows is mentioned, for example.

First, the resist composition of the above-described embodiment is applied on a support with a spinner or the like, and a bake (post-applied 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, an exposure device such as an electron beam drawing device or an EUV exposure device is used, and exposure through a mask (mask pattern) in which a predetermined pattern is formed, or electron beam without a mask pattern. After selective exposure by drawing by direct irradiation or the like is performed, a bake (post exposure bake (PEB)) treatment is performed, for example, at a temperature of 80 to 150°C for 40 to 120 seconds, preferably for 60 to 90 seconds. .

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

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

In the case of a solvent developing process, after the above developing treatment or rinsing treatment, a treatment in which the developer or rinsing liquid adhering on the pattern is removed with a supercritical fluid may be performed.

Drying is performed after developing treatment or after rinsing treatment. Moreover, in some cases, a baking treatment (post baking) may be performed after the development treatment.

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 with a predetermined|prescribed wiring pattern formed on it, etc. are mentioned. More specifically, a silicon wafer, a substrate made of metal such as copper, chromium, iron, or aluminum, and a glass substrate may be mentioned. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold, or the like can be used.

Further, as the support, an inorganic and/or organic film may be formed on a substrate as described above. 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 an underlayer organic film in a multilayer resist method.

Here, the multilayer resist method means forming at least one layer of an organic film (lower layer organic film) and at least one layer of a resist film (upper layer resist film) on a substrate, and using a resist pattern formed on the upper resist film as a mask. Thus, it is a method of performing patterning of the lower organic film, and it is believed 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 secured by the lower organic film, the resist film can be made thin, and fine patterns with a high aspect ratio can be formed.

In the multilayer resist method, basically, a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers (metal thin film, etc.) 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).

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

The method of exposing the resist film may be conventional exposure (dry exposure) performed in an inert gas such as air or nitrogen, or liquid immersion exposure (Liquid Immersion Lithography).

The liquid immersion exposure is an exposure method in which exposure (immersion exposure) is performed in the state of filling the resist film and the lens at the lowest position of the exposure apparatus with a solvent (liquid immersion medium) having a refractive index greater than the refractive index of air.

As the liquid immersion medium, a solvent having a refractive index larger than that of air and smaller than that of the resist film to be exposed is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.

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

Specific examples of the fluorine-based inert liquid include liquids mainly containing fluorine-based compounds 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. And the boiling point is preferably 70 to 180°C, and more preferably 80 to 160°C. If the fluorine-based inert liquid has a boiling point in 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 of the hydrogen atoms of 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.

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

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

As an alkali developer used in the development treatment in the alkaline development process, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) is exemplified.

As the organic solvent contained in the organic developer used for the developing treatment in the solvent developing process, any one capable of dissolving the component (A) (the component (A) before exposure) can be appropriately selected from known organic solvents. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents and ether solvents, and hydrocarbon solvents may be mentioned.

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

Among the organic solvents, there is also an organic solvent including a plurality of types of functional groups that characterize each of the above-described solvents in the structure, and in that case, it is assumed to correspond to any solvent type including the functional groups that the organic solvent has. For example, it is assumed that diethylene glycol monomethyl ether corresponds to any of alcohol-based solvents and ether-based solvents in the above classification.

The hydrocarbon-based solvent is a hydrocarbon solvent composed of a hydrocarbon which may be halogenated and does not have a substituent other than a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.

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

As a ketone solvent, for example, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl Ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthylketone, Isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), and the like. Among these, as a ketone solvent, methyl amyl ketone (2-heptanone) is preferable.

Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, 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, and propyl-3-methoxypropionate. Among these, as an ester solvent, butyl acetate is preferable.

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

In the organic developer, a known additive can be blended if necessary. As the additive, a surfactant is mentioned, for example. Although it does not specifically limit as surfactant, For example, an ionic or nonionic fluorine-type and/or silicone-type surfactant, etc. can be used. As the surfactant, a nonionic surfactant is preferable, and a nonionic fluorine surfactant or a nonionic silicone surfactant is more preferable.

When a surfactant is blended, the blending amount is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, and more preferably 0.01 to 0.5 mass% with respect to the total amount of the organic developer.

The developing treatment can be performed by a known developing method, for example, a method of immersing the support in a developer for a certain period of time (dip method), a method of stacking the developer on the surface of the support by surface tension and stopping for a certain period of time (paddle Method), a method of spraying a developer on the surface of a support (spray method), a method of continuously drawing a developer while scanning a nozzle at a constant speed on a support rotating at a constant speed (dynamic dispensing method) Etc. are mentioned.

As the organic solvent contained in the rinse treatment after the development in the solvent development process, for example, among the organic solvents used in the organic developer, those that are difficult to dissolve the resist pattern are appropriately selected and used. I can. Usually, at least one type of solvent selected from hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, alcohol-based solvents, amide-based solvents, and ether-based solvents is used. Among these, at least one type selected from hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, alcohol-based solvents and amide-based solvents is preferable, and at least one type selected from alcohol-based solvents and ester-based solvents is more preferable, Alcohol-based solvents are particularly preferred.

The alcohol-based 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 alone or in combination of two or more. Moreover, you may use it, mixing with an organic solvent or water other than the above. However, in consideration of developing characteristics, the amount of water to be mixed in the rinse liquid is preferably 30% by mass or less, more preferably 10% by mass or less, and still more preferably 5% by mass or less, with respect to the total amount of the rinse liquid. Particularly preferred is mass% or less.

In the rinse liquid, a known additive can be blended if necessary. As the additive, a surfactant is mentioned, for example. Examples of the surfactant include those similar to those described above, and a nonionic surfactant is preferable, and a nonionic fluorine surfactant or a nonionic silicone surfactant is more preferable.

When a surfactant is blended, the blending amount is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, and more preferably 0.01 to 0.5 mass% with respect to the total amount of the rinse liquid.

The rinse treatment (washing treatment) using the rinse liquid can be performed by a known rinse method. As a method of the rinsing treatment, for example, a method of continuously drawing out a rinse liquid on a support rotating at a constant speed (rotation coating method), a method of immersing the support in the rinse liquid for a certain period of time (dip method), and the surface of the support. The method of spraying the rinse liquid (spray method) etc. is mentioned.

According to the resist pattern forming method of the present embodiment described above, since the resist composition of the first embodiment described above is used, a resist pattern having high sensitivity and excellent lithography properties can be formed.

Example

Hereinafter, the present invention will be described in more detail by examples, but the present invention is not limited by these examples.

<Preparation of resist composition>

(Examples 1 to 21, Comparative Examples 1 to 3)

Each component shown in Tables 1-3 was mixed and dissolved, and the resist composition of each example was prepared, respectively.

In Tables 1-3, each abbreviation has the following meaning, respectively. The value in [] is the blending amount (parts by mass).

(A)-1: A polymer compound represented by the following general formula (A-1). This polymer compound (A-1) was obtained by radical polymerization using a monomer that induces a structural unit constituting the polymer compound in a predetermined molar ratio. With respect to this polymer compound (A-1), the weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement was 7000, and the molecular weight dispersion degree (Mw/Mn) was 1.70. ^The copolymerization composition ratio (ratio (molar ratio) of each constituent unit in the structural formula) determined by 13 C-NMR was l/m = 50/50.

[Chemical Formula 79]

(B1)-1 to (B1)-7: An acid generator comprising a compound each represented by the following formulas (B1-1) to (B1-7).

[Chemical Formula 80]

(D0)-1 to (D0)-7: An acid diffusion control agent comprising a compound each represented by the following formulas (D0-1) to (D0-7).

(D1)-1: An acid diffusion control agent comprising a compound represented by the following general formula (D1-1).

[Chemical Formula 81]

[Formula 82]

[Formula 83]

(S)-1: A mixed solvent of propylene glycol monomethyl ether acetate/propylene glycol monomethyl ether = 60/40 (mass ratio).

<Formation of resist pattern>

On an 8-inch silicon substrate subjected to hexamethyldisilazane (HMDS) treatment, the resist composition of each example was applied using a spinner, respectively, and prebaked (PAB) treatment for 60 seconds at a temperature of 110°C on a hot plate. Then, by drying, a resist film having a film thickness of 50 nm was formed.

Next, with respect to the resist film, using an electron beam drawing device JEOL-JBX-9300FS (manufactured by Nippon Electronics Co., Ltd.), with an acceleration voltage of 100 kV, the target size is 1:1 line and space with a line width of 50 nm to 20 nm. Drawing (exposure) as a pattern (hereinafter, "LS pattern") was performed. Then, heating (PEB) treatment was performed after exposure for 60 seconds at 90°C. Next, alkali development was performed for 60 seconds at 23°C using a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Oka Industrial Co., Ltd.).

Then, water rinse was performed for 15 seconds using pure water.

As a result, a 1:1 LS pattern having a line width of 50 nm to 20 nm was formed.

[Evaluation of optimal exposure amount (Eop)]

By the above <formation of a resist pattern>, the optimum exposure amount Eop (µC/cm 2) at which an LS pattern having a target size (line width of 50 nm) is formed was determined. This was shown in Tables 4-6 as "Eop (μC/cm 2 )".

[Evaluation of LWR (Line with Roughness)]

With respect to the LS pattern formed in the above <Formation of Resist Pattern>, 3σ, which is a measure representing LWR, was calculated. This was shown in Tables 4-6 as "LWR (nm)".

"3σ" is the standard deviation obtained from the measurement result by measuring 400 line positions in the length direction of the line with a scanning electron microscope (acceleration voltage 800 V, brand name: S-9380, manufactured by Hitachi High Technologies). The triple value (3σ) (unit: nm) of (σ) is shown.

The smaller the value of 3σ is, the smaller the roughness of the sidewalls of the line means that an LS pattern with a more uniform width is obtained.

[Evaluation of resolution]

By the above <formation of resist pattern>, the optimum exposure amount Eop (µC/cm 2) at which the LS pattern of the target size is formed was determined. And, when forming the LS pattern by gradually increasing the exposure amount from the optimum exposure amount Eop, the minimum size of the pattern resolved without collapsing was determined using a scanning electron microscope S-9380 (manufactured by Hitachi High-Technologies Corporation). This was shown in Tables 4-6 as "resolution (nm)".

From the results shown in Tables 4 to 6, according to the resist composition of the Example, compared to the resist composition of the Comparative Example, a resist pattern having excellent sensitivity, reduction in roughness, and resolution in formation of a resist pattern can be formed. Can be confirmed.

In the above, a preferred embodiment of the present invention has been described, but the present invention is not limited to this embodiment. Additions, omissions, substitutions, and other changes of configurations may be made without departing from the spirit of the present invention. The invention is not limited by the foregoing description, but only by the appended claims.

Claims (6)

As a resist composition that generates an acid by exposure and whose solubility in a developer is changed by the action of an acid,
A base component (A) whose solubility in a developer is changed by the action of an acid, and
Onium salt-based acid generator component (B) that generates an acid by exposure, and
It contains a compound (D0) consisting of an anionic moiety and a cation moiety represented by the following general formula (d0),
The resist composition, wherein at least one cation portion of the onium salt-based acid generator component (B) and the compound (D0) is a cation having an electron withdrawing group.

[In the formula, M ^m+ represents an m-valent organic cation. m is an integer of 1 or more. R ^d0 is a substituent. p is an integer of 0-3. When p is 2 or 3, a plurality of R ^d0 may be the same or different. q is an integer of 0-3. n is an integer of 2 or more. However, it is n + p ≤ (q × 2) + 5.] The method of claim 1,
The resist composition, wherein the compound (D0) is a compound composed of an anion moiety and a cation moiety represented by the following general formula (d0-1).

[In the formula, R ^d1 is an aryl group having an electron withdrawing group. R ^d2 and R ^d3 are each independently an aryl group which may have a substituent, or combine with each other to form a ring together with the sulfur atom in the formula. R ^d0 is a substituent. p is an integer of 0-3. When p is 2 or 3, a plurality of R ^d0 may be the same or different. q is an integer of 0-3. n is an integer of 2 or more. However, it is n + p ≤ (q × 2) + 5.] The method of claim 1,
The resist composition, wherein the cation moiety of the onium salt-based acid generator component (B) and the compound (D0) is both a cation having an electron withdrawing group. The method of claim 1,
The resist composition, wherein the electron withdrawing group is a fluorine atom, a fluorinated alkyl group, or a sulfonyl group. On a support, a step of forming a resist film using the resist composition according to any one of claims 1 to 4, a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern. Having, a method of forming a resist pattern. The method of claim 5,
In the step of exposing the resist film, the resist film is exposed to EUV (extreme ultraviolet) or EB (electron beam).