JP2019207296A - Resist composition, resist pattern forming method, compound, and acid generator - Google Patents

Abstract

To provide a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a resist pattern forming method using the resist composition.SOLUTION: The resist composition contains a compound represented by general formula (bd1) and comprising an anionic moiety and a cationic moiety. In the formula (bd1), Rx-Rxeach represent a hydrocarbon group or a hydrogen atom or may be bonded to each other to form a ring structure; Ry-Ryeach represent a hydrocarbon group or a hydrogen atom or may be bonded to each other to form a ring structure; Rz-Rzeach represent a hydrocarbon group or a hydrogen atom or may be bonded to each other to form a ring structure; at least one of Rx-Rx, Ry-Ryand Rz-Rzhas an anionic group; and Mrepresents an organic cation having an electron-withdrawing group.SELECTED DRAWING: None

Description

  The present invention relates to a resist composition, a resist pattern forming method, a compound, and an acid generator.

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

Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions.
Conventionally, as a resist material satisfying such requirements, a chemically amplified resist composition containing a base material component whose solubility in a developing solution is changed by the action of an acid and an acid generator component that generates an acid upon exposure. Is used.
For example, when the developer is an alkali developer (alkaline development process), the positive chemically amplified resist composition includes a resin component (base resin) that increases the solubility in an alkali developer due to the action of acid and acid generation. What contains an agent component is generally used. When a resist film formed using such a resist composition is selectively exposed at the time of resist pattern formation, an acid is generated from the acid generator component in the exposed area, and the polarity of the base resin increases due to the action of the acid. Thus, the exposed portion of the resist film becomes soluble in the alkaline developer. Therefore, by carrying out alkali development, a positive pattern in which an unexposed portion of the resist film remains as a pattern is formed.
On the other hand, when such a chemically amplified resist composition is applied to a solvent development process using a developer containing an organic solvent (organic developer), the organic development is relatively increased when the polarity of the base resin increases. Since the solubility in the solution is lowered, the unexposed portion of the resist film is dissolved and removed by the organic developer, and a negative resist pattern in which the exposed portion of the resist film remains as a pattern is formed. Such a solvent development process for forming a negative resist pattern is sometimes referred to as a negative development process.

The base resin used in the chemically amplified resist composition generally has a plurality of structural units in order to improve lithography properties and the like.
For example, in the case of a resin component whose solubility in an alkaline developer is increased by the action of an acid, a structural unit containing an acid-decomposable group that is decomposed by the action of an acid generated from an acid generator or the like and increases in polarity is used. In addition, a structural unit containing a lactone-containing cyclic group, a structural unit containing a polar group such as a hydroxyl group, and the like are used in combination.

In the formation of the resist pattern, the behavior of the acid generated from the acid generator component by exposure is one factor that greatly affects the lithography characteristics.
A wide variety of acid generators have been proposed so far for use in chemically amplified resist compositions. For example, onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, diazomethane acid generators, nitrobenzyl sulfonate acid generators, iminosulfonate acid generators, disulfone acid generators, etc. It has been known.
As the onium salt acid generator, those having an onium ion such as triphenylsulfonium in the cation part are mainly used. In general, the anion portion of an onium salt acid generator uses an alkyl sulfonate ion or a fluorinated alkyl sulfonate ion in which part or all of the hydrogen atoms of the alkyl group are substituted with a fluorine atom. .
In addition, in order to improve lithography characteristics in the formation of a resist pattern, an onium salt acid generator having an anion having a specific structure including an aromatic ring as an anion portion of the onium salt acid generator has been proposed. (For example, refer to Patent Document 1).

Japanese Patent No. 5149236

With further advancement of lithography technology and further miniaturization of resist patterns, for example, lithography with an electron beam or EUV aims to form a fine pattern of several tens of nm. Thus, the smaller the resist pattern dimension is, the more the resist composition is required to have high lithography characteristics such as high sensitivity to an exposure light source and roughness reduction.
However, in the resist composition containing the conventional onium salt-based acid generator as described above, it is difficult to obtain a desired resist pattern shape or the like when an attempt is made to increase sensitivity to an exposure light source such as EUV. There were problems and it was difficult to satisfy all of these characteristics.

  The present invention has been made in view of the above circumstances, and is a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, and a resist composition containing the acid generator And a resist pattern forming method using the resist composition.

In order to solve the above problems, the present invention employs the following configuration.
That is, the first aspect of the present invention is a resist composition that generates an acid upon exposure and changes its solubility in a developing solution by the action of an acid, and the solubility in the developing solution changes by the action of an acid. And a compound (BD1) composed of an anion part and a cation part represented by the following general formula (bd1).

［式中、Ｒｘ^１〜Ｒｘ^４は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^１〜Ｒｘ^４、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。ｍは１以上の整数であって、Ｍ^ｍ＋は、電子求引性基を有するｍ価の有機カチオンを表す。］

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ]

  According to a second aspect of the present invention, there is provided 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 resist film after the exposure. A resist pattern forming method comprising a step of developing to form a resist pattern.

  A third aspect of the present invention is a compound comprising an anion portion and a cation portion represented by the following general formula (bd1).

［式中、Ｒｘ^１〜Ｒｘ^４は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^１〜Ｒｘ^４、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。ｍは１以上の整数であって、Ｍ^ｍ＋は、電子求引性基を有するｍ価の有機カチオンを表す。］

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ]

  According to a fourth aspect of the present invention, there is provided an acid generator comprising the compound according to the third aspect.

According to the present invention, a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a resist using the resist composition A pattern forming method can be provided.
According to the resist composition of the present invention, in the formation of a resist pattern, a resist pattern with improved lithography properties (roughness reduction, etc.) can be formed, and high sensitivity can be achieved.

In the present specification and claims, “aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
The “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified.
The “halogenated alkyl group” is a group in which part or all of the hydrogen atoms of the alkyl group are substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
“Fluorinated alkyl group” or “fluorinated alkylene group” refers to a group in which part or all of the hydrogen atoms of an alkyl group or alkylene group are substituted with fluorine atoms.
“Structural unit” means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
In the case of describing “may have a substituent” or “may have a substituent”, the case where a hydrogen atom (—H) is substituted with a monovalent group, the case of a methylene group (—CH ₂ And the case where-) is substituted with a divalent group.
“Exposure” is a concept including general irradiation of radiation.

“A structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ ═CH—COOH) is substituted with an organic group.
In the acrylate ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent (R ^α0 ) for substituting the hydrogen atom bonded to the α-position carbon atom is an atom or group other than a hydrogen atom, such as an alkyl group having 1 to 5 carbon atoms or a halogenated group having 1 to 5 carbon atoms. An alkyl group etc. are mentioned. In addition, itaconic acid diesters in which the substituent (R ^α0 ) is substituted with a substituent containing an ester bond, and α-hydroxyacrylic esters in which the substituent (R ^α0 ) is substituted with a hydroxyalkyl group or a group with a modified hydroxyl group thereof Shall be included. The α-position carbon atom of the acrylate ester is a carbon atom to which the carbonyl group of acrylic acid is bonded unless otherwise specified.
Hereinafter, an acrylate 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 acrylate ester. Further, the acrylate ester and the α-substituted acrylate ester may be collectively referred to as “(α-substituted) acrylate ester”.

“Structural unit derived from acrylamide” means a structural unit formed by cleavage of an ethylenic double bond of acrylamide.
In acrylamide, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, or one or both of the hydrogen atoms of the amino group of acrylamide may be substituted with a substituent. Note that the α-position carbon atom of acrylamide is a carbon atom to which the carbonyl group of acrylamide is bonded unless otherwise specified.
Examples of the substituent for substituting the hydrogen atom bonded to the α-position carbon atom of acrylamide are the same as those listed as the α-position substituent (substituent (R ^α0 )) in the α-substituted acrylic ester. Can be mentioned.

“Structural unit derived from hydroxystyrene” means a structural unit formed by cleavage of an ethylenic double bond of hydroxystyrene. “A structural unit derived from a hydroxystyrene derivative” means a structural unit formed by cleavage of an ethylenic double bond of a hydroxystyrene derivative.
“Hydroxystyrene derivative” is a concept including those in which the hydrogen atom at the α-position of hydroxystyrene is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. These derivatives include those in which the hydrogen atom of the hydroxy styrene of the α-position hydrogen atom optionally substituted with a substituent is substituted with an organic group; the hydrogen atom in the α-position is substituted with a substituent The thing etc. which the substituents other than a hydroxyl group couple | bonded with the benzene ring of good hydroxystyrene are mentioned. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include the same substituents as those mentioned as the substituent at the α-position in the α-substituted acrylic ester.

The “structural unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative” means a structural unit formed by cleavage of an ethylenic double bond of vinyl benzoic acid or a vinyl benzoic acid derivative.
The “vinyl benzoic acid derivative” is a concept including a compound in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. These derivatives include those in which the hydrogen atom of the carboxy group of vinylbenzoic acid, which may be substituted with a hydrogen atom at the α-position, is substituted with an organic group; the hydrogen atom at the α-position is substituted with a substituent. Examples thereof include those in which a substituent other than a hydroxyl group and a carboxy group is bonded to the benzene ring of vinyl benzoic acid. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.

The “styrene derivative” is a concept including those in which the hydrogen atom at the α-position of styrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. Examples of these derivatives include those in which a substituent is bonded to a benzene ring of hydroxystyrene in which the hydrogen atom at the α-position may be substituted with a substituent. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
“Structural unit derived from styrene” and “structural unit derived from styrene derivative” mean a structural unit formed by cleavage of an ethylenic double bond of styrene or a styrene derivative.

The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group). , N-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
Specific examples of the halogenated alkyl group as the substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as the substituent at the α-position” are substituted with a halogen atom. It is done. 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.
Specific examples of the hydroxyalkyl group as a substituent at the α-position include a group in which part or all of the hydrogen atoms of the “alkyl group as the substituent at the α-position” are substituted with a hydroxyl group. 1-5 are preferable and, as for the number of the hydroxyl groups in this hydroxyalkyl group, 1 is the most preferable.

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

(Resist composition)
The resist composition according to the first aspect of the present invention generates an acid upon exposure and changes its solubility in a developer due to the action of an acid, and has a solubility in a developer due to the action of an acid. A base material component (A) that changes (hereinafter also referred to as “component (A)”) and a compound (BD1) represented by general formula (bd1) (hereinafter also referred to as “(BD1) component”) are contained. .
As one embodiment of the resist composition, the resist composition containing the component (A) and an acid generator component (B) that generates an acid upon exposure (hereinafter also referred to as “component (B)”). Is mentioned. Preferably, in addition to the component (A) and the component (B), a base component (hereinafter also referred to as “component (D)”) that traps the acid generated from the component (B) upon exposure (that is, controls the diffusion of the acid). ) Are further included.
In the resist composition of the present embodiment, the component (BD1) can be used as the component (B) or the component (D) by selecting an anionic group in the molecule.

  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 action of the acid While the solubility of the component (A) in the developer changes, the solubility of the component (A) in the developer does not change in the unexposed portion of the resist film. A difference in solubility in the developer occurs. 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. When the resist composition is negative, the resist film is not formed. The exposed portion is dissolved and removed to form a negative resist pattern.

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

The resist composition of this embodiment has an acid generating ability to generate an acid upon exposure, and in addition to the component (B), the component (A) may generate an acid upon exposure.
When the component (A) generates an acid upon exposure, the component (A) becomes a “base material component that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid”.
When the component (A) is a base material component that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid, the component (A1) described later generates an acid upon exposure, and A polymer compound whose solubility in a developer is changed by the action of an acid is preferable. Examples of such a polymer compound include a resin having a structural unit that generates an acid upon exposure. A well-known thing can be used for the monomer which derives the structural unit which generates an acid by exposure.

<(A) component>
In the resist composition of this embodiment, the component (A) is a base material component whose solubility in a developer is changed by the action of an acid.
In the present invention, the “base component” is an organic compound having a film forming ability, and preferably an organic compound having a molecular weight of 500 or more is used. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved, and in addition, it becomes easy to form a nano-level resist pattern.
Organic compounds used as the base material 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, the “low molecular compound” refers to a non-polymer having a molecular weight of 500 or more and less than 4000.
As the polymer, those having a molecular weight of 1000 or more are usually used. Hereinafter, “resin”, “polymer compound” or “polymer” refers to a polymer having a molecular weight of 1000 or more.
As the molecular weight of the polymer, a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used.

When the resist composition of the present embodiment is a “negative resist composition for an alkali development process” that forms a negative resist pattern in an alkali development process, or a “solvent that forms a positive resist pattern in a solvent development process In the case of a “positive resist composition for development process”, the component (A) is preferably a base component (A-2) (hereinafter referred to as “component (A-2)”) that is soluble in an alkaline developer. In addition, a crosslinking agent component is blended. In such a resist composition, for example, when an acid is generated from the component (B) by exposure, the acid acts to cause crosslinking between the component (A-2) and the crosslinking agent component. The solubility in the liquid is reduced (the solubility in the organic developer is increased). Therefore, in the formation of a resist pattern, when a resist film obtained by coating the resist composition on a support is selectively exposed, the resist film exposed portion is hardly soluble in an alkali developer (in an organic developer). On the other hand, the unexposed portion of the resist film remains soluble in an alkali developer (slightly soluble in an organic developer) and does not change. Therefore, a negative resist is developed by developing with an alkali developer. A pattern is formed. At this time, a positive resist pattern is formed by developing with an organic developer.
As a preferable component (A-2), a resin soluble in an alkali developer (hereinafter referred to as “alkali-soluble resin”) is used.
Examples of the alkali-soluble resin include α- (hydroxyalkyl) acrylic acid or α- (hydroxyalkyl) acrylic acid alkyl ester (preferably having 1 to 5 carbon atoms) disclosed in, for example, JP-A-2000-206694. A resin having a structural unit derived from at least one selected from alkyl ester); a hydrogen atom bonded to a carbon atom at the α-position having a sulfonamide group, which is disclosed in US Pat. No. 6,949,325, is substituted with a substituent Acrylic resin or polycycloolefin resin which may have been prepared; containing fluorinated alcohol, disclosed in US Pat. The hydrogen atom bonded to the carbon atom may be substituted with a substituent. Acrylic resin; disclosed in Japanese 2006-259582 discloses, polycycloolefin resins having fluorinated alcohol is preferred because it can form a resist pattern with minimal swelling.
The α- (hydroxyalkyl) acrylic acid is a hydrogen atom bonded to the α-position carbon atom to which the carboxy group is bonded, among the acrylic acid in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent. One or both of acrylic acid having an atom bonded thereto and α-hydroxyalkylacrylic acid having a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) bonded to the α-position carbon atom are shown. .
As the crosslinking agent component, for example, it is preferable to use an amino-based crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group, or a melamine-based crosslinking agent, because a good resist pattern with less swelling is easily formed. . It is preferable that the compounding quantity of a crosslinking agent component is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

When the resist composition of the present embodiment is a “positive resist composition for an alkali development process” that forms a positive resist pattern in an alkali development process, or a “solvent that forms a negative resist pattern in a solvent development process In the case of a “developing process negative resist composition”, the component (A) is preferably a substrate component (A-1) whose polarity is increased by the action of an acid (hereinafter referred to as “component (A-1)”). ) Is used. By using the component (A-1), the polarity of the base material component changes before and after the exposure, so that good development contrast can be obtained not only in the alkali development process but also in the solvent development process.
When the alkali development process is applied, the component (A-1) is hardly soluble in an alkali developer before exposure. For example, when acid is generated from the component (B) by exposure, The polarity increases and the solubility in an alkaline developer increases. Therefore, in the formation of a resist pattern, when a resist film obtained by applying the resist composition on a support is selectively exposed, the exposed portion of the resist film changes from poorly soluble to soluble in an alkaline developer. On the other hand, since the unexposed portion of the resist film remains hardly soluble in alkali and does not change, a positive resist pattern is formed by alkali development.
On the other hand, when applying the solvent development process, the component (A-1) is highly soluble in an organic developer before exposure, and when acid is generated from the component (B) by exposure, the action of the acid As a result, the polarity becomes higher and the solubility in an organic developer decreases. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition on the support is selectively exposed, the resist film exposed portion is changed from being soluble to hardly soluble in the organic developer. On the other hand, the resist film unexposed part remains soluble and does not change, so by developing with an organic developer, it is possible to create a contrast between the exposed part and the unexposed part. It is formed.

In the resist composition of this embodiment, as the component (A), one type may be used alone, or two or more types may be used in combination.
In the resist composition of this embodiment, the component (A) is preferably the component (A-1). That is, the resist composition of the present embodiment is a “positive resist composition for an alkali development process” that forms a positive resist pattern in an alkali development process, or a “solvent development” that forms a negative resist pattern in a solvent development process. It is preferably a “negative resist composition for process”. As the component (A), at least one of a high molecular compound and a low molecular compound can be used.
When the component (A) is the component (A-1), the component (A-1) preferably includes the resin component (A1) (hereinafter also referred to as “component (A1)”).

-About (A1) component (A1) component is a resin component, and what contains the high molecular compound which has the structural unit (a1) containing the acid-decomposable group which increases polarity by the effect | action of an acid is preferable.
As the component (A1), in addition to the structural unit (a1), those having a structural unit (a10) containing a hydroxystyrene skeleton are also preferable.
In addition to the structural unit (a1), the component (A1) further includes a structural unit (a2) containing a lactone-containing cyclic group, an —SO ₂ — containing cyclic group, or a carbonate-containing cyclic group. Is also preferable.
In addition to the structural unit (a1), the component (A1) further includes the structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group (provided that the structural unit (a1) or the structural unit (a2) Those having (except applicable ones) are also preferred.
In addition, the component (A1) may have a structural unit other than the structural unit (a1), the structural unit (a2), the structural unit (a3), and the structural unit (a10).

<< Unit (a1) >>
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid.
The “acid-decomposable group” is an acid-decomposable group that can cleave at least part of bonds in the structure of the acid-decomposable group by the action of an acid.
Examples of the acid-decomposable group whose polarity increases by the action of an acid include a group that decomposes by the action of an acid to generate a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, a sulfo group (—SO ₃ H), and the like. Among these, a polar group containing —OH in the structure (hereinafter sometimes referred to as “OH-containing polar group”) is preferable, a carboxy group or a hydroxyl group is more preferable, and a carboxy group is particularly preferable.
More specifically, examples of the acid-decomposable group include groups in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).

Here, the “acid-dissociable group” means (i) a group having acid-dissociable properties 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, Alternatively, (ii) after a partial bond is cleaved by the action of an acid, a further decarboxylation reaction occurs, whereby a bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group is cleaved. Both of the resulting groups.
The acid-dissociable group constituting the acid-decomposable group must be a group having a lower polarity than the polar group generated by dissociation of the acid-dissociable group. Is dissociated, a polar group having a polarity higher than that of the acid dissociable group is generated to increase the polarity. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer changes relatively. When the developer is an alkaline developer, the solubility increases. When the developer is an organic developer, the solubility increases. Decrease.

Examples of the acid dissociable group include those that have been proposed so far as the acid dissociable group of the base resin for the chemically amplified resist composition.
Specifically, as an acid dissociable group of a base resin for a chemically amplified resist composition, specifically, “acetal type acid dissociable group” and “tertiary alkyl ester type acid dissociable group” described below are used. Group "and" tertiary alkyloxycarbonyl acid dissociable group ".

Acetal type acid dissociable groups:
Examples of the acid dissociable group that protects a carboxy group or a hydroxyl group among the polar groups include, for example, an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter referred to as “acetal acid dissociable group”). May be included).

［式中、Ｒａ’^１、Ｒａ’^２は水素原子またはアルキル基である。Ｒａ’^３は炭化水素基であって、Ｒａ’^３は、Ｒａ’^１、Ｒａ’^２のいずれかと結合して環を形成してもよい。］

[Wherein, 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 either Ra ′ ¹ or Ra ′ ² to form a ring. ]

In formula (a1-r-1), at least one of Ra ′ ¹ and Ra ′ ² is preferably a hydrogen atom, and more preferably both are hydrogen atoms.
In the case where Ra ′ ¹ or Ra ′ ² is an alkyl group, the alkyl group includes the alkyl group mentioned as the substituent that may be bonded to the carbon atom at the α-position in the description of the α-substituted acrylate ester. The same thing is mentioned, A C1-C5 alkyl group is preferable. Specifically, a linear or branched alkyl group is preferable. 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, and the like can be given. More preferred is a methyl group.

In formula (a1-r-1), examples of the hydrocarbon group for Ra ′ ³ include a linear or branched alkyl group and 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. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

  The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and the like is preferably isopropyl group.

When Ra ′ ³ is 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 in which one hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group which is a polycyclic group, a group in which one hydrogen atom is removed from a polycycloalkane is preferable, and the polycycloalkane is preferably a group having 7 to 12 carbon atoms, specifically Includes adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

When the cyclic hydrocarbon group of Ra ′ ³ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, 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; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Can be mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group in Ra ′ ³ is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); A group obtained by removing one hydrogen atom from an aromatic compound (for example, biphenyl, fluorene, etc.); a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (for example, a benzyl group) Phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, arylalkyl groups such as 2-naphthylethyl group, etc.). The alkylene group bonded to the aromatic hydrocarbon ring or the aromatic heterocyclic ring preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom. preferable.

The cyclic hydrocarbon group in Ra ′ ³ may have a substituent. Examples of the substituent group, ^{e.g., -R P1, -R P2 -O-} R P1, -R P2 -CO-R P1, -R P2 -CO-OR P1, -R P2 -O-CO-R P1, -R ^{P2 -OH,} (collectively hereinafter these substituents also referred to as ^{"Ra 05".) -R} P2 -CN or ^-R P2 -COOH and the like.
Here, R ^P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic having 6 to 30 carbon atoms. Group hydrocarbon group. ^RP2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent group having 6 to 30 carbon atoms. Is an aromatic hydrocarbon group. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, the aliphatic cyclic 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 above substituents alone, or may have one or more of each of the above substituents.
Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group. .
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group. Monocyclic aliphatic saturated hydrocarbon group; bicyclo [2.2.2] octanyl group, tricyclo [5.2.1.02,6] decanyl group, tricyclo [3.3.1.13,7] decanyl group And a polycyclic aliphatic saturated hydrocarbon group such as tetracyclo [6.2.13, 6.02,7] dodecanyl group, adamantyl group and the like.
Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

When Ra ′ ³ is bonded to either Ra ′ ¹ or Ra ′ ² to form a ring, the cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

Tertiary alkyl ester type acid dissociable group:
Among the polar groups, examples of the acid dissociable group that protects the carboxy group include an acid dissociable group represented by the following general formula (a1-r-2).
In addition, among the acid dissociable groups represented by the following formula (a1-r-2), those composed of an alkyl group may be hereinafter referred to as “tertiary alkyl ester type acid dissociable groups” for convenience. .

［式中、Ｒａ’^４〜Ｒａ’^６はそれぞれ炭化水素基であって、Ｒａ’^５、Ｒａ’^６は互いに結合して環を形成してもよい。］

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

Examples of the hydrocarbon group for Ra ′ ⁴ include a linear or branched alkyl group, a linear or cyclic alkenyl group, and a cyclic hydrocarbon group.
A linear or branched alkyl group or a cyclic hydrocarbon group (an aliphatic hydrocarbon group that is a monocyclic group, an aliphatic hydrocarbon group that is a polycyclic group, or an aromatic hydrocarbon group) in Ra ′ ⁴ ) May be the same as Ra ′ ³ above.
The chain or cyclic alkenyl group in Ra ′ ⁴ is preferably an alkenyl group having 2 to 10 carbon atoms.
Examples of the hydrocarbon group for Ra ′ ⁵ and Ra ′ ⁶ include the same groups as those described for Ra ′ ³ above.

When Ra ′ ⁵ and Ra ′ ⁶ are bonded to each other to form a ring, a group represented by the following general formula (a1-r2-1) or a group represented by the following general formula (a1-r2-2) Preferred examples include groups represented by general formula (a1-r2-3) shown below.
On the other hand, when Ra ′ ^{4 to} Ra ′ ⁶ are not bonded to each other and are independent hydrocarbon groups, groups represented by the following general formula (a1-r2-4) are preferably exemplified.

［式（ａ１−ｒ２−１）中、Ｒａ’^１０は、炭素数１〜１０のアルキル基、又は下記一般式（ａ１−ｒ２−ｒ１）で表される基を示す。Ｒａ’^１１はＲａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基を示す。式（ａ１−ｒ２−２）中、Ｙａは炭素原子である。Ｘａは、Ｙａと共に環状の炭化水素基を形成する基である。この環状の炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ^０１〜Ｒａ^０３は、それぞれ独立して、水素原子、炭素数１〜１０の１価の鎖状飽和炭化水素基又は炭素数３〜２０の１価の脂肪族環状飽和炭化水素基である。この鎖状飽和炭化水素基及び脂肪族環状飽和炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ^０１〜Ｒａ^０３の２つ以上が互いに結合して環状構造を形成していてもよい。式（ａ１−ｒ２−３）中、Ｙａａは炭素原子である。Ｘａａは、Ｙａａと共に脂肪族環式基を形成する基である。Ｒａ^０４は、置換基を有していてもよい芳香族炭化水素基である。式（ａ１−ｒ２−４）中、Ｒａ’^１２及びＲａ’^１３は、それぞれ独立に、炭素数１〜１０の１価の鎖状飽和炭化水素基又は水素原子である。この鎖状飽和炭化水素基が有する水素原子の一部又は全部は置換されていてもよい。Ｒａ’^１４は、置換基を有していてもよい炭化水素基である。＊は結合手を示す（以下同じ）。］

[In the formula (a1-r2-1), Ra ′ ¹⁰ represents an alkyl group having 1 to 10 carbon atoms or a group represented by the following general formula (a1-r2-r1). Ra ′ ¹¹ represents a group which forms 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 that forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of the cyclic hydrocarbon group may be substituted. Ra ^{01 to} Ra ⁰³ are each independently a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group may be substituted. Two or more of Ra ^{01 to} Ra ⁰³ may be bonded to each other to form a cyclic structure. In the formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra ⁰⁴ 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 the chain saturated hydrocarbon group may be substituted. Ra ′ ¹⁴ is a hydrocarbon group which may have a substituent. * Indicates a bond (hereinafter the same). ]

［式中、Ｙａ^０は、第４級炭素原子である。Ｒａ^０３１、Ｒａ^０３２及びＲａ^０３３は、それぞれ独立に、置換基を有していてもよい炭化水素基である。但し、Ｒａ^０３１、Ｒａ^０３２及びＲａ^０３３のうちの１つ以上は、少なくとも一つの極性基を有する炭化水素基である。］

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

In the above formulas (a1-r2-1), Ra 'alkyl group having 1 to 10 carbon atoms ^10, Ra in formula (a1-r-1)' as linear or branched alkyl group of ³ The groups mentioned are preferred. Ra ′ ¹⁰ is preferably an alkyl group having 1 to 5 carbon atoms.

In the formula (a1-r2-r1), Ya ⁰ is a quaternary carbon atom. That is, there are four adjacent carbon atoms bonded to Ya ⁰ (carbon atom).

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

The linear alkyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ preferably has 1 to 5 carbon atoms, more preferably 1 to 4 and even more preferably 1 or 2. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.
The branched alkyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and the like is preferable.
The chain or cyclic alkenyl group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferably an alkenyl group having 2 to 10 carbon atoms.

The cyclic hydrocarbon group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group in which one hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group which is a polycyclic group, a group in which one hydrogen atom is removed from a polycycloalkane is preferable, and the polycycloalkane is preferably a group having 7 to 12 carbon atoms, specifically Includes adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20, still more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Can be mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring. Specifically, the aromatic hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); an aromatic group containing two or more aromatic rings A group in which one hydrogen atom has been removed from a compound (for example, biphenyl, fluorene, etc.); a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (for example, a benzyl group, a phenethyl group) 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, arylalkyl groups such as 2-naphthylethyl group, etc.). The alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

When the hydrocarbon group represented by Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is substituted, examples of the substituent include a hydroxy group, a carboxy group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc. ), Alkoxy groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), alkyloxycarbonyl groups and the like.

Among these, the hydrocarbon group which may have a substituent in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferably a linear or branched alkyl group which may have a substituent, A linear alkyl group is more preferred.

However, at least one of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least a polar group.
The “hydrocarbon group having a polar group” is one in which a methylene group (—CH ₂ —) constituting a hydrocarbon group is substituted with a polar group, or at least one hydrogen atom constituting a hydrocarbon group is Anything substituted with a polar group is included.
The “hydrocarbon group having a polar group” is preferably a functional group represented by the following general formula (a1-p1).

［式中、Ｒａ^０７は、炭素数２〜１２の２価の炭化水素基を表す。Ｒａ^０８は、ヘテロ原子を含む２価の連結基を表す。Ｒａ^０６は、炭素数１〜１２の１価の炭化水素基を表す。ｎ_ｐ０は、１〜６の整数である。］

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

In the formula (a1-p1), Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms.
Ra ⁰⁷ has 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, still more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms.
The hydrocarbon group in Ra ⁰⁷ is preferably a chain or cyclic aliphatic hydrocarbon group, and more preferably a chain hydrocarbon group.
Examples of Ra ⁰⁷ include ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1, 7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc. Linear alkanediyl group of propane-1,2-diyl group, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, pentane-1,4-diyl group, 2 -Branched chain alkanediyl group such as methylbutane-1,4-diyl group; cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1 , 5-Di Cycloalkanediyl groups such as yl groups; polycyclic cyclic groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. And divalent alicyclic hydrocarbon groups.
Among the above, an alkanediyl group is preferable, and a linear alkanediyl group is more preferable.

In the formula (a1-p1), Ra ⁰⁸ represents a divalent linking group containing a hetero atom.
As Ra ⁰⁸ , for example, —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O—, —C (═O) —NH— , —NH—, —NH—C (═NH) — (H may be substituted with a substituent such as an alkyl group or an acyl group), —S—, —S (═O) ₂ —, — S (= O) _2- O- etc. are mentioned.
Among these, from the viewpoint of solubility in a developer, —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O— are preferable. O- and -C (= O)-are particularly preferable.

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

Examples of the hydrocarbon group in Ra ⁰⁶ include a chain hydrocarbon group or a cyclic hydrocarbon group, or a hydrocarbon group in which a chain and a ring are combined.
Examples of the chain hydrocarbon group include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n -Heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group and the like can be mentioned.

The cyclic hydrocarbon group may be an alicyclic hydrocarbon group or an aromatic hydrocarbon group.
The alicyclic hydrocarbon group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a methyl group. Examples thereof include cycloalkyl groups such as cyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkane-1-yl group, and norbornyl. Group, methylnorbornyl group, isobornyl group and the like.
Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group. , Biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like.

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

In the formula (a1-p1), n _p0 is an integer of 1 to 6, preferably an integer of 1 to 3, more preferably 1 or 2, and even more preferably 1.

Specific examples of the hydrocarbon group having at least a polar group are shown below.
In the following formula, * is a bond bonded to a quaternary carbon atom (Ya ⁰ ).

In the formula (a1-r2-r1), among Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the number of hydrocarbon groups having at least a polar group is one or more. ^May be appropriately determined in consideration of solubility of, for example, one or two of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are preferable, and one is particularly preferable.

  The hydrocarbon group having at least a polar group may have a substituent other than the polar group. Examples of the substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.) and a halogenated alkyl group having 1 to 5 carbon atoms.

In 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 formula (a1-r-1) Or the group quoted as the aliphatic hydrocarbon group which is a polycyclic group is preferable.

In the formula (a1-r2-2), as the cyclic hydrocarbon group formed by Xa together with Ya, the cyclic monovalent hydrocarbon group in Ra ′ ³ in the formula (a1-r-1) (aliphatic And a group obtained by further removing one or more hydrogen atoms from a hydrocarbon group.
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 in 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 ^{01 to} Ra ⁰³ include, for example, a methyl group, an ethyl group, a propyl group, a butyl group, and pentyl. Group, hexyl group, heptyl group, octyl group, decyl group and the like.
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra ^{01 to} Ra ⁰³ include, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclodecyl group. Group, monocyclic aliphatic saturated hydrocarbon group such as cyclododecyl group; bicyclo [2.2.2] octanyl group, tricyclo [5.2.1.02,6] decanyl group, tricyclo [3.3.1] .13,7] decanyl group, polycyclo [6.2.1.13,6.02,7] dodecanyl group, polycyclic aliphatic saturated hydrocarbon group such as adamantyl group and the like.
Ra ^{01 to} Ra ⁰³ are preferably a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms from the viewpoint of ease of synthesis of the monomer compound for deriving the structural unit (a1). Among these, a hydrogen atom, a methyl group, and an ethyl group are more preferable, and a hydrogen atom is particularly preferable.

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

Examples of the group containing a carbon-carbon double bond formed by bonding two or more of Ra ^{01 to} Ra ⁰³ to each other to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, methyl Examples include a cyclohexenyl group, a cyclopentylideneethenyl group, a cyclohexylideneethenyl group, and the like. Among these, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneethenyl group are preferable from the viewpoint of ease of synthesis of the monomer compound for deriving the structural unit (a1).

In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is an aliphatic carbonization which is a monocyclic group or a polycyclic group of Ra ′ ³ in formula (a1-r-1). The groups mentioned as hydrogen groups are preferred.
In formula (a1-r2-3), examples of the aromatic hydrocarbon group for Ra ⁰⁴ include a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra ⁰⁴ is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, and more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene. Further, a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene is more preferred, a group obtained by removing one or more hydrogen atoms from benzene or naphthalene is particularly preferred, and a group obtained by removing one or more hydrogen atoms from benzene is most preferred. preferable.

Examples of the substituent that Ra ^{04 in} formula (a1-r2-3) may have include, for example, a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom (a fluorine atom, a chlorine atom, Bromine atoms, etc.), alkoxy groups (methoxy groups, ethoxy groups, propoxy groups, butoxy groups, etc.), alkyloxycarbonyl groups and the like.

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 in Ra ′ ¹² and Ra ′ ¹³ is a monovalent chain saturated hydrocarbon having 1 to 10 carbon atoms in the above Ra ⁰¹ to Ra ⁰³ . The thing similar to group is mentioned. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group may be substituted.
Ra ′ ¹² and Ra ′ ¹³ are preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, still more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. preferable.
In the case where the chain saturated hydrocarbon group represented by Ra ′ ¹² and Ra ′ ¹³ is substituted, examples of the substituent include the same groups as Ra ⁰⁵ described above.

In formula (a1-r2-4), Ra ′ ¹⁴ represents a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group for Ra ′ ¹⁴ include a linear or branched alkyl group, and 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. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched alkyl group in Ra ′ ¹⁴ preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and the like is preferable.

When Ra ′ ¹⁴ is 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 in which one hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group which is a polycyclic group, a group in which one hydrogen atom is removed from a polycycloalkane is preferable, and the polycycloalkane is preferably a group having 7 to 12 carbon atoms, specifically Includes adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

Examples of the aromatic hydrocarbon group for Ra ′ ¹⁴ include the same aromatic hydrocarbon groups as for Ra ⁰⁴ . Among them, Ra ′ ¹⁴ is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, and more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene. Preferably, a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene is more preferred, a group obtained by removing one or more hydrogen atoms from naphthalene or anthracene is particularly preferred, and a group obtained by removing one or more hydrogen atoms from naphthalene is preferred. Most preferred.
Examples of the substituent that Ra ′ ¹⁴ may have include the same substituents that Ra ⁰⁴ may have.

When Ra ′ ^{14 in the} formula (a1-r2-4) is a naphthyl group, the position bonded to the tertiary carbon atom in the formula (a1-r2-4) is the 1-position or 2-position of the naphthyl group. Either may be sufficient.
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 1-position, 2-position of the anthryl group, or Any of the ninth positions may be used.

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

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

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

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

Tertiary alkyloxycarbonyl acid dissociable group:
Examples of the acid dissociable group for protecting the hydroxyl group among the polar groups include an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as “tertiary alkyloxycarbonyl acid dissociable group for convenience”). ”).

［式中、Ｒａ’^７〜Ｒａ’^９はそれぞれアルキル基である。］

[Wherein, Ra ′ ^{7 to} Ra ′ ⁹ each represents an alkyl group. ]

In formula (a1-r-3), Ra ′ ^{7 to} Ra ′ ⁹ are each preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms.
Further, the total carbon number of each alkyl group is preferably 3 to 7, more preferably 3 to 5 carbon atoms, and most preferably 3 to 4 carbon atoms.

  As the structural unit (a1), a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, a structural unit derived from acrylamide, hydroxystyrene or hydroxy A structural unit in which at least a part of hydrogen atoms in a hydroxyl group of a structural unit derived from a styrene derivative is protected by a substituent containing the acid-decomposable group, a structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative; Examples include a structural unit in which at least part of hydrogen atoms in C (═O) —OH is protected by a substituent containing the acid-decomposable group.

Among the above, the structural unit (a1) is preferably a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent.
Preferred specific examples of the structural unit (a1) include structural units represented by general formula (a1-1) or (a1-2) shown below.

［式中、Ｒは、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基である。Ｖａ^１は、エーテル結合を有していてもよい２価の炭化水素基である。ｎ_ａ１は、０〜２の整数である。Ｒａ^１は、上記の一般式（ａ１−ｒ−１）又は（ａ１−ｒ−２）で表される酸解離性基である。Ｗａ^１はｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は１〜３の整数であり、Ｒａ^２は上記の一般式（ａ１−ｒ−１）又は（ａ１−ｒ−３）で表される酸解離性基である。］

[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 a n _a2 +1 valent hydrocarbon group, n _a2 is an integer of 1 to 3, and Ra ² is represented by the above general formula (a1-r-1) or (a1-r-3). It is an acid dissociable group. ]

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, specifically, a methyl group or an 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 part 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.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and is most preferably a hydrogen atom or a methyl group in terms of 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 a divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, and the like.

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. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). Alkylmethylene groups such as _2- , —C (CH ₃ ) (CH ₂ CH ₃ ) —, —C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) —, —C (CH ₂ CH ₃ ) ₂ —; _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group that is linear or branched. Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those similar to the linear aliphatic hydrocarbon group or the 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. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group as a divalent hydrocarbon group in Va ¹ is a hydrocarbon group having an aromatic ring.
The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. . However, the carbon number does not include the carbon number in the substituent.
Specific examples of the aromatic ring of the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; some of the carbon atoms constituting the aromatic hydrocarbon ring are heterogeneous. Aromatic heterocycles substituted with atoms and the like. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group) ) In which one of the hydrogen atoms is substituted with an alkylene group (for example, arylalkyl such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.) And a group obtained by further removing one hydrogen atom from the aryl group in the group). The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2, and particularly preferably 1.

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

In the formula (a1-2), the n _a2 +1 valent 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, may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include 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. Examples thereof include a combination of an aliphatic hydrocarbon group containing a ring in the structure.
The n _a2 +1 valence 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 the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

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

As the structural unit (a1) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
As the structural unit (a1), a structural unit represented by the formula (a1-1) is more preferable because characteristics (sensitivity, shape, etc.) in lithography using an electron beam or EUV can be further improved.
Among these, as the structural unit (a1), those including a structural unit represented by general formula (a1-1-1) shown below are particularly preferable.

［式中、Ｒａ^１”は、一般式（ａ１−ｒ２−１）、（ａ１−ｒ２−３）又は（ａ１−ｒ２−４）で表される酸解離性基である。］

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

In the formula (a1-1-1), R, Va ¹ and _{n a1} is, R in the formula (a1-1), the same as Va ¹ and _{n a1.}
The explanation of the acid dissociable group represented by the general formula (a1-r2-1), (a1-r2-3) or (a1-r2-4) is as described above.

The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol%, preferably 10 to 75 mol%, based on the total (100 mol%) of all the structural units constituting the component (A1). More preferably, 30-70 mol% is further more preferable.
By setting the proportion of the structural unit (a1) to be equal to or higher than the lower limit value of the preferable range, lithography properties such as sensitivity, resolution, and roughness improvement are improved. On the other hand, when it is not more than the upper limit value of the above preferable range, it is possible to balance with other structural units, and various lithography properties are improved.

<< Constitutional unit containing hydroxystyrene skeleton (a10) >>
The component (A1) preferably has a structural unit (a10) containing a hydroxystyrene skeleton in addition to the structural unit (a1).
As the structural unit (a10), for example, a structural unit represented by general formula (a10-1) shown below is preferably exemplified.

［式中、Ｒは、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基である。Ｙａ^ｘ１は、単結合又は２価の連結基である。Ｗａ^ｘ１は、（ｎ_ａｘ１＋１）価の芳香族炭化水素基である。ｎ_ａｘ１は、１〜３の整数である。］

[In 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 linking group. Wa ^x1 is an (n _ax1 +1) valent aromatic hydrocarbon group. n _ax1 is an integer of 1 to 3. ]

In said formula (a10-1), R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group.
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, specifically, methyl group, ethyl group, propyl group, isopropyl group, n- Examples thereof include a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms of R is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and is most preferably a hydrogen atom or a methyl group in terms of industrial availability.

In the formula (a10-1), Ya ^x1 is a single bond or a divalent linking group.
Suitable examples of the divalent linking group in Ya ^x1 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 having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like.

... 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, Numbers 1 to 4 are more preferable, and carbon numbers 1 to 3 are most preferable.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). Alkylmethylene groups such as _2- , —C (CH ₃ ) (CH ₂ CH ₃ ) —, —C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) —, —C (CH ₂ CH ₃ ) ₂ —; _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

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

... An aliphatic hydrocarbon group containing a ring in the structure As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group that may contain a substituent containing a hetero atom in the ring structure (A group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, the cyclic fat And a group in which an aromatic 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 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. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms. Examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

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, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. Most preferred are a methoxy group and an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

.. Aromatic hydrocarbon group in Ya ^x1 The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, 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 carbon number does not include the carbon number in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Can be mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); an aromatic compound containing two or more aromatic rings A group in which two hydrogen atoms have been removed from (for example, biphenyl, fluorene, etc.); A group substituted with an alkylene group (for example, from an aryl group in an arylalkyl group such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group to hydrogen) A group in which one atom is further removed). The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

In the aromatic hydrocarbon group, a hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an 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, and most 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 the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

-A divalent linking group containing a hetero atom:
When Ya ^x1 is a divalent linking group containing a hetero atom, preferred examples of the linking group include —O—, —C (═O) —O—, —C (═O) —, —O—C. (═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-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 - C (═O) —O—, —C (═O) —O—Y ²¹ —, — [Y ²¹ —C (═O) —O] _{m ″} —Y ²² —, —Y ²¹ —O—C ( Group represented by ═O) —Y ²² — or —Y ²¹ —S (═O) ₂ —O—Y ²² —, wherein Y ²¹ and Y ²² each independently have a substituent. A divalent hydrocarbon group, It is an oxygen atom, m "is an integer of 0 to 3. ] Etc. are mentioned.
The divalent linking group containing a hetero atom is —C (═O) —NH—, —C (═O) —NH—C (═O) —, —NH—, —NH—C (═NH )-, The H may be substituted with a substituent such as an alkyl group or acyl. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O-Y 21 -, - [Y 21 - C (═O) —O] _{m ″} —Y ²² —, —Y ²¹ —O—C (═O) —Y ²² — or —Y ²¹ —S (═O) ₂ —O—Y ²² —, wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, and the divalent hydrocarbon group is exemplified in the description of the divalent linking group. And (the divalent hydrocarbon group which may have a substituent).
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, particularly a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ″} —Y ²² —, m ″ is an integer of 0 to 3, preferably an integer of 0 to 2, Or 1 is more preferable, and 1 is particularly preferable. That is, the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ″} —Y ²² — is represented by the formula —Y ²¹ —C (═O) —O—Y ²² —. A group represented by the formula — (CH ₂ ) _{a ′} —C (═O) —O— (CH ₂ ) _{b ′} — is preferred, in which a ′ is 1 to 10 The integer of 1-8 is preferable, the integer of 1-5 is more preferable, 1 or 2 is further more preferable, and 1 is the most preferable, b 'is an integer of 1-10, 1-8 An integer is preferable, an integer of 1 to 5 is more preferable, 1 or 2 is more preferable, and 1 is most preferable.

As Ya ^x1 , a single bond, an ester bond [—C (═O) —O—], an ether bond (—O—), —C (═O) —NH—, a linear or branched alkylene group Or a combination thereof, and a single bond is particularly more preferable.

In the formula (a10-1), Wa ^x1 is a (n _ax1 +1) valent aromatic hydrocarbon group.
Examples of the aromatic hydrocarbon group in Wa ^x1 include a group in which (n _ax1 +1) hydrogen atoms are removed from an aromatic ring. The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, 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; aromatic heterocycles in which a part of carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Can be mentioned. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

In said formula (a10-1), _nax1 is an integer of 1-3, 1 or 2 is preferable and 1 is more preferable.

Specific examples of the structural unit represented by the general formula (a10-1) are shown below.
In the following formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

As the structural unit (a10) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
In the component (A1), the proportion of the structural unit (a10) is, for example, 0 to 80 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1), and 10 to 80 Mol% is preferable, 20 to 70 mol% is more preferable, and 30 to 60 mol% is particularly preferable.
By setting the proportion of the structural unit (a10) to be equal to or higher than the lower limit of the above preferable range, lithography properties such as sensitivity, resolution, and roughness improvement are improved. On the other hand, when it is not more than the upper limit value of the above preferable range, it is possible to balance with other structural units, and various lithography properties are improved.

≪Structural unit (a2) ≫
The component (A1) includes, in addition to the structural unit (a1), a structural unit (a2) (provided that the structural unit (a1) further includes a lactone-containing cyclic group, an —SO ₂ -containing cyclic group, or a carbonate-containing cyclic group). Those having (except for those falling under a1) are preferred.
The lactone-containing cyclic group, —SO ₂ — containing cyclic group, or carbonate-containing cyclic group of the structural unit (a2) is used to adhere the resist film to the substrate when the component (A1) is used for forming a resist film. It is effective in improving the sex. Further, by having the structural unit (a2), for example, the acid diffusion length is appropriately adjusted, the adhesion of the resist film to the substrate is improved, the solubility during development is appropriately adjusted, the etching resistance is improved, and the like. Due to this effect, the lithography properties and the like are improved.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C (═O) — in the ring skeleton. The lactone ring is counted as the first ring. When only the lactone ring is present, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group in the structural unit (a2) is not particularly limited, and any lactone-containing cyclic group can be used. Specific examples include groups represented by general formulas (a2-r-1) to (a2-r-7) shown below.

［式中、Ｒａ’^２１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は−ＳＯ_２−含有環式基であり；Ａ”は酸素原子（−Ｏ−）もしくは硫黄原子（−Ｓ−）を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数であり、ｍ’は０または１である。］

[Wherein, Ra ′ ²¹ each independently represents 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. Yes; R ″ is a hydrogen atom, alkyl group, lactone-containing cyclic group, carbonate-containing cyclic group, or —SO ₂ -containing cyclic group; A ″ is an oxygen atom (—O—) or a sulfur atom (— S—) may be an alkylene group having 1 to 5 carbon atoms, an oxygen atom or a sulfur atom, n ′ is an integer of 0 to 2, and m ′ is 0 or 1. ]

In the general formula (a2-r-1) ~ (a2-r-7), the alkyl group in Ra ^'21, preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and a hexyl group. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.
The alkoxy group in the ra ^'21, preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, groups of the the Ra 'group and an oxygen atom mentioned as the alkyl group in ²¹ (-O-) are linked and the like.
Examples of the halogen atom in Ra ′ ²¹ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
'Examples of the halogenated alkyl group for ^21, the Ra' Ra part or all of the hydrogen atoms of the alkyl group in ²¹ can be mentioned it has been substituted with the aforementioned 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 any hydrogen atom, alkyl group, lactone-containing cyclic group, carbonate-containing cyclic group, or —SO ₂ -containing cyclic group. It is.
The alkyl group for R ″ may be linear, branched or cyclic, and preferably has 1 to 15 carbon atoms.
When R ″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. preferable.
When R ″ is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a fluorine atom Or a group obtained by removing one or more hydrogen atoms from a monocycloalkane which may or may not be substituted with a fluorinated alkyl group; a polycycloalkane such as a bicycloalkane, tricycloalkane or tetracycloalkane A group in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane, and more specifically, a group in which one or more hydrogen atoms have been removed; Examples include groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as cyclodecane or tetracyclododecane. That.
Examples of the lactone-containing cyclic group for R ″ include the same groups as those represented by general formulas (a2-r-1) to (a2-r-7).
The carbonate-containing cyclic group in R ″ is the same as the carbonate-containing cyclic group described later, specifically, groups represented by general formulas (ax3-r-1) to (ax3-r-3), respectively. Is mentioned.
The —SO ₂ — containing cyclic group in R ″ is the same as the later-described —SO ₂ — containing cyclic group, and specifically, is represented by the general formulas (a5-r-1) to (a5-r-4) And groups represented respectively by
As the hydroxyalkyl group in Ra ′ ²¹ , those having 1 to 6 carbon atoms are preferable, and specifically, a group in which at least one hydrogen atom of the alkyl group in Ra ′ ²¹ is substituted with a hydroxyl group can be mentioned. .

In the general formulas (a2-r-2), (a2-r-3), and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A ″ is linear or branched. An alkylene group is preferable, and examples include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include the terminal of the alkylene group or carbon. between atoms -O- or -S- can be mentioned a group intervening, for example, _{-O-CH 2 -, - CH} 2 -O-CH 2 -, - S-CH 2 -, - CH 2 -S-CH _As A ″, an alkylene group having 1 to 5 carbon atoms or —O— is preferable, an alkylene group having 1 to 5 carbon atoms is more preferable, and a methylene group is most preferable.

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

The “—SO ₂ -containing cyclic group” refers to a cyclic group containing a ring containing —SO ₂ — in the ring skeleton, specifically, the sulfur atom (S) in —SO ₂ — is It is a cyclic group that forms part of the ring skeleton of the cyclic group. The ring containing —SO ₂ — in the ring skeleton is counted as the first ring, and when it is only the ring, it is a monocyclic group, and when it has another ring structure, it is a polycyclic group regardless of the structure. Called. The —SO ₂ — containing cyclic group may be a monocyclic group or a polycyclic group.
-SO ₂ - containing cyclic group, in particular, -O-SO ₂ - within the ring skeleton cyclic group containing, i.e. -O-SO ₂ - -O-S- medium is a part of the ring skeleton A cyclic group containing a sultone ring to be formed is preferable.
More specifically, examples of the —SO ₂ -containing cyclic group include groups represented by general formulas (a5-r-1) to (a5-r-4) shown below.

［式中、Ｒａ’^５１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は−ＳＯ_２−含有環式基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数である。］

[Wherein, Ra ′ ⁵¹ independently represents 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. Yes; R ″ is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a —SO ₂ — containing cyclic group; A ″ is a carbon that may contain an oxygen atom or a sulfur atom It is an alkylene group of formula 1-5, an oxygen 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 ″ represents the general formulas (a2-r-2), (a2-r-3), and (a2-r-5). Same as A ″ in the middle.
As the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in Ra ′ ⁵¹ , the above general formulas (a2-r-1) to ( a2-r-7) as in the same as those exemplified in the description of the Ra ^'21 of the like.
Specific examples of groups represented by general formulas (a5-r-1) to (a5-r-4) are given below. “Ac” in the formula represents an acetyl group.

The “carbonate-containing cyclic group” refers to a cyclic group containing a ring (carbonate ring) containing —O—C (═O) —O— in the ring skeleton. When the carbonate ring is counted as the first ring, the carbonate ring alone is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.
Any carbonate ring-containing cyclic group can be used without any particular limitation. Specific examples include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

［式中、Ｒａ’^ｘ３１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子、アルキル基、ラクトン含有環式基、カーボネート含有環式基、又は−ＳＯ_２−含有環式基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｐ’は０〜３の整数であり、ｑ’は０または１である。］

[ ^Wherein , Ra ′ ^x31 each independently represents 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. Yes; R ″ is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a —SO ₂ — containing cyclic group; A ″ is a carbon that may contain an oxygen atom or a sulfur atom An alkylene group having 1 to 5 atoms, an oxygen atom or a sulfur atom, p ′ is an integer of 0 to 3, and q ′ is 0 or 1. ]

In the general formulas (ax3-r-2) to (ax3-r-3), A ″ represents the general formulas (a2-r-2), (a2-r-3), (a2-r-5). Same as A ″ in the middle.
As the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in Ra ′ ³¹ , the above general formulas (a2-r-1) to ( a2-r-7) as in the same as those exemplified in the description of the Ra ^'21 of the like.
Specific examples of groups represented by general formulas (ax3-r-1) to (ax3-r-3) are shown below.

As the structural unit (a2), a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent is preferable.
The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基である。Ｙａ^２１は単結合または２価の連結基である。Ｌａ^２１は−Ｏ−、−ＣＯＯ−、−ＣＯＮ（Ｒ’）−、−ＯＣＯ−、−ＣＯＮＨＣＯ−又は−ＣＯＮＨＣＳ−であり、Ｒ’は水素原子またはメチル基を示す。ただしＬａ^２１が−Ｏ−の場合、Ｙａ^２１は−ＣＯ−にはならない。Ｒａ^２１はラクトン含有環式基、カーボネート含有環式基、又は−ＳＯ_２−含有環式基である。］

[In 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 represents —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 is not —CO—. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or an —SO ₂ -containing cyclic group. ]

  In the formula (a2-1), R is the same as described 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 the viewpoint of industrial availability.

In formula (a2-1), the divalent linking group of Ya ²¹ is not particularly limited, but may be a divalent hydrocarbon group which may have a substituent, or a divalent linking group containing a hetero atom. Etc. are preferable. The explanation for the divalent hydrocarbon group which may have a substituent in Ya ^{21 and} the divalent linking group containing a hetero atom is the substitution in Ya ^x1 in the general formula (a10-1). This is the same as described for the divalent hydrocarbon group which may have a group and the divalent linking group containing a hetero atom.
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. .

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.
The lactone-containing cyclic group, -SO ₂ -containing cyclic group, and carbonate-containing cyclic group in Ra ²¹ are each represented by the general formulas (a2-r-1) to (a2-r-7) described above. Groups represented by general formulas (a5-r-1) to (a5-r-4), groups represented by general formulas (ax3-r-1) to (ax3-r-3), respectively. Are preferable.
Among them, a lactone-containing cyclic group or a —SO ₂ — containing cyclic group is preferable, and the general formula (a2-r-1), (a2-r-2), (a2-r-6) or (a5-r) is preferable. The groups represented by -1) are more preferable. Specifically, the chemical formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r- Any group represented by lc-6-1), (r-sl-1-1), and (r-sl-1-18) is more preferred.

As the structural unit (a2) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is 1 to 50 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). It is preferably 5 to 45 mol%, more preferably 10 to 40 mol%, particularly preferably 10 to 30 mol%.
By setting the proportion of the structural unit (a2) to a preferable lower limit value or more, the effect of containing the structural unit (a2) is sufficiently obtained, and when it is equal to or lower than the upper limit value, balance with other structural units is achieved. And various lithographic properties are improved.

≪Structural unit (a3) ≫
In addition to the structural unit (a1), the component (A1) further includes the structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group (provided that the structural unit (a1) and the structural unit (a2)) Are preferred). The component (A1) has the structural unit (a3), for example, appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, appropriately adjusting the solubility during development, and etching resistance. Due to the effects such as improvement, the lithography properties and the like are improved.

Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which part of the hydrogen atoms 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 linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group. For example, a resin for a resist composition for an ArF excimer laser can be appropriately selected from those proposed. The cyclic group is preferably a polycyclic group, and more preferably 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxyl group, a cyano group, a carboxy group, or an 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 have been removed from bicycloalkane, tricycloalkane, tetracycloalkane and the like. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane. Industrially preferable.

The structural unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any structural unit can be used.
The structural unit (a3) is a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and includes a polar group-containing aliphatic hydrocarbon group A structural unit is preferred.
The structural unit (a3) is derived from a hydroxyethyl ester of acrylic acid 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. The structural unit is preferred.
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 formula (a3) -2) and the structural unit represented by the formula (a3-3) are preferable.

［式中、Ｒは前記と同じであり、ｊは１〜３の整数であり、ｋは１〜３の整数であり、ｔ’は１〜３の整数であり、ｌは１〜５の整数であり、ｓは１〜３の整数である。］

[Wherein, R is the same as defined above, j is an integer of 1 to 3, k is an integer of 1 to 3, t ′ is an integer of 1 to 3, and l is an integer of 1 to 5] And s is an integer of 1 to 3. ]

In formula (a3-1), j is preferably 1 or 2, and more preferably 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.
j is preferably 1, and a hydroxyl group bonded to the 3-position of the adamantyl group is particularly preferred.

  In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.

  In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. In these, a 2-norbornyl group or a 3-norbornyl group is preferably bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5th or 6th position of the norbornyl group.

The structural unit (a3) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a3), it is preferably 1 to 40 mol%, more preferably 2 to 30 mol%, based on the total of all structural units constituting the component (A1). 5-25 mol% is further more preferable, and 5-20 mol% is especially preferable.
By setting the proportion of the structural unit (a3) to be equal to or higher than the lower limit value of the preferable range, an effect obtained by including the structural unit (a3) is sufficiently obtained, and is equal to or lower than the upper limit value of the preferable range. It is possible to balance with other structural units, and various lithographic properties are improved.

≪Other structural units≫
The component (A1) may have other structural units other than the structural unit (a1), the structural unit (a10), the structural unit (a2), and the structural unit (a3) described above.
As other structural units, for example, a structural unit (a9) represented by the general formula (a9-1) described later, a structural unit derived from styrene, a structural unit derived from a styrene derivative (however, the structural unit (a10 ), And a structural unit containing an acid non-dissociable aliphatic cyclic group.

Structural unit (a9):
The structural unit (a9) is a structural unit represented by the following general formula (a9-1).

［式中、Ｒは、水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基である。Ｙａ^９１は、単結合又は２価の連結基である。Ｙａ^９２は、２価の連結基である。Ｒ^９１は、置換基を有していてもよい炭化水素基である。］

[In formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Ya ⁹¹ is a single bond or a divalent linking group. Ya ⁹² is a divalent linking group. R ⁹¹ is a hydrocarbon group which may have a substituent. ]

In the formula (a9-1), R is the same as described 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 the viewpoint of industrial availability.

In the formula (a9-1), examples of the divalent linking group in Ya ⁹¹ include the same divalent linking groups as in Ya ^x1 in the general formula (a10-1). Of these, Ya ⁹¹ is preferably a single bond.

In the formula (a9-1), examples of the divalent linking group in Ya ⁹² include the same divalent linking groups as Ya ^x1 in the general formula (a10-1) described above.
In the divalent linking group in Ya ^92, the divalent hydrocarbon group which may have a substituent is preferably a linear or branched aliphatic hydrocarbon group.
In the divalent linking group in Ya ⁹² , examples of the divalent linking group containing a hetero atom include —O—, —C (═O) —O—, —C (═O) —, and —O—C. (═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 -, - C (= S) -, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 ^{-O -, - Y 21 -C (} = O) -O -, - C (= O) -O - Y 21, [Y 21 -C (= O) -O] m '-Y 22 - or - A group represented by Y ²¹ —O—C (═O) —Y ²² —, wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent. , O is an oxygen atom, and m ′ is 0-3. It is an integer. ] Etc. are mentioned. Especially, -C (= O)-and -C (= S)-are preferable.

In the formula (a9-1), examples of the hydrocarbon group for R ⁹¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.
The alkyl group for R ⁹¹ preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and may be linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group and the like are preferable.
The monovalent alicyclic hydrocarbon group for R ⁹¹ preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably a group having 7 to 12 carbon atoms. Examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The aryl group for R ⁹¹ is preferably one having 6 to 18 carbon atoms, more preferably one having 6 to 10 carbon atoms, and particularly preferably a phenyl group.
The aralkyl group in R ⁹¹ is preferably an aralkyl group in which an alkylene group having 1 to 8 carbon atoms and the above “aryl group in R ⁹¹ ” are bonded, and an alkylene group having 1 to 6 carbon atoms and the above “aryl group in R ⁹¹ ”. Is more preferable, and an aralkyl group in which an alkylene group having 1 to 4 carbon atoms and the above “aryl group in R ⁹¹ ” are bonded is particularly preferable.
In the hydrocarbon group for R ⁹¹ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms. More preferably. Especially, it is especially preferable that it is the perfluoroalkyl group by which all the hydrogen atoms of the alkyl group mentioned above were substituted by the fluorine atom.

The hydrocarbon group for R ⁹¹ may have a substituent. Examples of the substituent include a halogen atom, an oxo group (═O), a hydroxyl group (—OH), an amino group (—NH ₂ ), —SO ₂ —NH _{2 and the} like. Moreover, a part of carbon atoms constituting the hydrocarbon group may be substituted with a substituent containing a hetero atom. Examples of the substituent containing a hetero atom include -O-, -NH-, -N =, -C (= O) -O-, -S-, -S (= O) _2- , -S (= O ) ₂ -O-.
In R ⁹¹ , examples of the hydrocarbon group having a substituent include lactone-containing cyclic groups respectively represented by the aforementioned general formulas (a2-r-1) to (a2-r-7).

Further, in R ⁹¹ , the hydrocarbon group having a substituent is a —SO ₂ — containing cyclic group represented by each of the above general formulas (a5-r-1) to (a5-r-4); Examples thereof include a substituted aryl group represented by a chemical formula and a monovalent heterocyclic group.

  Among the structural units (a9), structural units represented by general formula (a9-1-1) shown below are preferable.

［式中、Ｒは前記と同様であり、Ｙａ^９１は単結合または２価の連結基であり、Ｒ^９１は置換基を有していてもよい炭化水素基であり、Ｒ^９２は酸素原子又は硫黄原子である。］

[Wherein, R is as defined above, Ya ⁹¹ is a single bond or a divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and R ⁹² is an oxygen atom or It is a sulfur atom. ]

In the general formula (a9-1-1), description of Ya ⁹¹ , R ⁹¹ and R is the same as described above. R ⁹² is an oxygen atom or a sulfur atom.

Specific examples of the structural unit represented by the formula (a9-1) or the general formula (a9-1-1) are shown below. In the following formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

As the structural unit (a9) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
When the component (A1) has the structural unit (a9), the proportion of the structural unit (a9) is 1 to 40 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). It is preferable that it is 3-30 mol%, 5-25 mol% is further more preferable, and 10-20 mol% is especially preferable.
By setting the proportion of the structural unit (a9) to be equal to or higher than the lower limit of the preferable range, for example, the acid diffusion length is appropriately adjusted, the adhesion of the resist film to the substrate is increased, and the solubility during development is appropriate. The effect of adjusting the etching resistance and improving the etching resistance can be obtained, and when it is not more than the upper limit of the above preferable range, it is possible to balance with other structural units, and various lithographic characteristics are improved.

As the component (A1) contained in the resist composition, one type may be used alone, or two or more types may be used in combination.
The component (A1) preferably contains the polymer compound (A1-1) having the structural unit (a1) (hereinafter also referred to as “component (A1-1)”).
Preferred examples of the component (A1-1) include a polymer compound having a repeating structure of the structural unit (a1) and the structural unit (a2), and a repeating structure of the structural unit (a1) and the structural unit (a10). Examples thereof include polymer compounds.
In addition to the combination of the above two structural units, the structural units described above may be combined as appropriate according to the desired effect as the third or more structural units. The third structural unit is preferably at least one of the structural unit (a3) and the structural unit (a9).

The component (A1) is obtained by dissolving a monomer for deriving each structural unit in a polymerization solvent, and starting radical polymerization such as azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (for example, V-601), etc. It can manufacture by adding an agent and superposing | polymerizing. Alternatively, the component (A1) includes a monomer that derives the structural unit (a1), and a precursor monomer that induces a structural unit other than the structural unit (a1) as necessary (a monomer having a functional group protected), Can be dissolved in a polymerization solvent, polymerized by adding a radical polymerization initiator as described above, and then subjected to a deprotection reaction. In the 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 ) at the terminal is used. _{A 2-} OH group may be introduced. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing

The mass average molecular weight (Mw) of the component (A1) (polystyrene conversion standard by gel permeation chromatography (GPC)) is not particularly limited, preferably 1000 to 50000, more preferably 2000 to 30000, 3000 to 20000 is more preferable.
When the Mw of the component (A1) is less than or equal to the preferable upper limit value in this range, there is sufficient solubility in a resist solvent to be used as a resist. The resist pattern has a good cross-sectional shape.
The dispersity (Mw / Mn) of the component (A1) is not particularly limited, but is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.1 to 2.0. . In addition, Mn shows a number average molecular weight.

-About (A2) component The resist composition of this embodiment does not correspond to the said (A1) component as a (A) component, but is a base-material component (henceforth "(A2) which changes the solubility with respect to a developing solution by the effect | action of an acid. ) Component ”)) may be used in combination.
The component (A2) is not particularly limited, and may be arbitrarily selected from a number of conventionally known base components for chemically amplified resist compositions.
As the component (A2), one type of high molecular compound or 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, still more preferably 75% by mass or more, and 100% by mass with respect to the total mass of the component (A). It may be. When the proportion is 25% by mass or more, a resist pattern excellent in various lithography properties such as high sensitivity, resolution, and roughness improvement is easily formed. Such an effect is particularly remarkable in lithography using an electron beam or EUV.

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

<Compound (BD1)>
In the resist composition of this embodiment, the component (BD1) is a compound composed of an anion portion and a cation portion represented by the following general formula (bd1).

［式中、Ｒｘ^１〜Ｒｘ^４は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^１〜Ｒｘ^４、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。ｍは１以上の整数であって、Ｍ^ｍ＋は、電子求引性基を有するｍ価の有機カチオンを表す。］

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ]

During Anion Formula for (bd1), Rx ¹ ~Rx ⁴ each independently represent a hydrocarbon may have a substituent hydrogen group or a hydrogen atom, or two or more are bonded to each other A ring structure may be formed.
Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.
Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it.

The hydrocarbon groups in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ may each be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a cyclic hydrocarbon group, or a chain It may be a hydrocarbon group.
For example, the hydrocarbon group that may have a substituent in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ includes a cyclic group or a substituent that may have a substituent. Examples thereof include a chain alkyl group which may have a chain, or a chain alkenyl group which may have a substituent.

Cyclic group which may have a substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. ^Further, cyclic hydrocarbon group in ^{Rx 1 ~Rx 4, Ry 1 ~Ry} 2, Rz 1 ~Rz 4 may contain a hetero atom as such a heterocyclic ring.

The aromatic hydrocarbon groups in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ are hydrocarbon groups 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, and particularly preferably 6 to 15 carbon atoms, Most preferably, it has 6 to 12 carbon atoms. However, the number of carbons does not include the number of carbons in the substituent.
Rx ¹ to Rx ^4, the ^Ry 1 ^{~Ry 2,} Rz 1 ^~Rz specifically as aromatic ring within the aromatic hydrocarbon group in the ^4, benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or their aromatic rings An aromatic heterocycle in which a part of the carbon atoms constituting is substituted with a heteroatom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. The aromatic ring of the aromatic hydrocarbon group in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ preferably does not contain a hetero atom from the viewpoint of compatibility with the component (A). Aromatic rings such as benzene, fluorene, naphthalene, anthracene, phenanthrene and biphenyl are more preferred.
Specific examples of the aromatic hydrocarbon group in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ include a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, phenyl group, Naphthyl group, etc.), a group in which one of the hydrogen atoms of the aromatic ring is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2- And arylalkyl groups such as naphthylethyl group). The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

Examples of the cyclic aliphatic hydrocarbon group in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ include 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 obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), an alicyclic hydrocarbon group is linear or branched Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group and a group in which an 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 in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among these, the polycycloalkane includes polycycloalkanes having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; condensed ring systems such as a cyclic group having a steroid skeleton A polycycloalkane having a polycyclic skeleton is more preferable.

Among them, the cyclic aliphatic hydrocarbon group in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane or polycycloalkane. A group obtained by removing one hydrogen atom from a monocycloalkane is more preferred, and a group obtained by removing one hydrogen atom from cyclopentane or cyclohexane is particularly preferred.

The linear aliphatic hydrocarbon group that may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and 1 to 4 carbon atoms. Is more preferable, and C1-C3 is the most preferable. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
The branched aliphatic hydrocarbon group that may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, and 3 or 4 carbon atoms. Is more preferable, and a carbon number of 3 is most preferable. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). Alkylmethylene groups such as _2- , —C (CH ₃ ) (CH ₂ CH ₃ ) —, —C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) —, —C (CH ₂ CH ₃ ) ₂ —; _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

In addition, as the cyclic group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ , R ^XYZ is a lactone-containing cyclic group for —COOR ^XYZ and —OC (═O) R ^XYZ , carbonate-containing cyclic group or -SO 2 _- may also be mentioned those containing cyclic groups.

Examples of the substituent in the cyclic group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a nitro group, and a carbonyl group. Etc.
The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
As the halogenated alkyl group as a substituent, a part or all of hydrogen atoms such as an alkyl group having 1 to 5 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, and the like And a group substituted with a halogen atom.
The carbonyl group as a substituent is a group that substitutes a methylene group (—CH ₂ —) constituting a cyclic hydrocarbon group.
Among ^them, as the substituent in the cyclic group of ^{Rx 1 ~Rx 4, Ry 1 ~Ry} 2, Rz 1 ~Rz 4, from the viewpoint of compatibility with the component (A), an alkyl group, a halogen atom, a halogenated alkyl Group is preferred, and an alkyl group is more preferred.

Chain alkyl group which may have a substituent:
The linear alkyl group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1,1-dimethylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1- Examples include ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

A chain alkenyl group which may have a substituent:
The chain alkenyl group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ may be linear or branched, and preferably has 2 to 10 carbon atoms, 2 to 5 carbon atoms are more preferable, 2 to 4 carbon atoms are more preferable, and 3 carbon atoms are particularly preferable. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group and the like.
Among the above, the chain alkenyl group is preferably a linear alkenyl group, more preferably a vinyl group or propenyl group, and particularly preferably a vinyl group.

Examples of the substituent in the chain alkyl group or alkenyl group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ include an alkoxy group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, a cyclic group, and the like in the ^{Rx 1 ~Rx 4, Ry 1 ~Ry} 2, Rz 1 ~Rz 4. Among these, as the substituent in the chain alkyl group or alkenyl group of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ , from the viewpoint of compatibility with the component (A), a halogen atom, halogen And the groups mentioned as the cyclic group in Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ are preferable, and Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ¹ to The groups listed as the cyclic group for Rz ⁴ are more preferable.

Rx ¹ As the hydrocarbon group in ^{~Rx 4, Ry 1 ~Ry 2,} Rz 1 ~Rz 4, among the above-mentioned hydrocarbon group which may have a substituent cyclic group having a substituent A chain alkyl group which may be present is preferred.

In the formula (bd1), Ry ^{1 to} Ry ² may be bonded to each other to form a ring structure.
The ring structure formed by the Ry ¹ to Ry ² shares one side of the six-membered ring in the formula (bd1) (bond between the carbon atoms to which Ry ¹ and Ry ² are respectively bonded). It may be an alicyclic hydrocarbon or an aromatic hydrocarbon. Further, this ring structure may be a polycyclic structure composed of other ring structures.

The alicyclic hydrocarbon formed by Ry ^{1 to} Ry ² may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon, monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon, polycycloalkane is preferable. The polycycloalkane preferably has 7 to 30 carbon atoms, specifically, a polycycloalkane having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; A polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton is more preferable.

The aromatic hydrocarbon ring formed by Ry ^{1 to} Ry ² is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocycle in which a part of carbon atoms constituting these aromatic rings is substituted with a heteroatom. A ring etc. are mentioned. From the viewpoint of compatibility with the component (A), the aromatic hydrocarbon ring formed by Ry ^{1 to} Ry ² preferably does not contain a heteroatom, and aromatics such as benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, etc. A ring is more preferred.

The ring structure (alicyclic hydrocarbon, aromatic hydrocarbon) formed by Ry ^{1 to} Ry ² may have a substituent. The substituent herein, ^Rx 1 ^{to Rx} 4 described ^{above, Ry 1 ~Ry 2, Rz 1} ~Rz 4 cyclic substituents in group (e.g., alkyl group, alkoxy group, halogen atom, halogenated alkyl group , Hydroxyl group, nitro group, carbonyl group, etc.). Among them, as the substituent in the ring structure Ry ¹ to Ry ² are formed, from the viewpoint of the compatibility with component (A), an alkyl group, a halogen atom, such as a halogenated alkyl group and more preferably an alkyl group.

Among them, the ring structure formed by Ry ^{1 to} Ry ² is more preferably an aromatic hydrocarbon which may have a substituent from the viewpoint of shortening the diffusion of acid generated by exposure and controlling the diffusion of acid.

In the formula (bd1), two or more of Rz ^{1 to} Rz ⁴ may be bonded to each other to form a ring structure. For example, Rz ¹ may form a ring structure with any of Rz ^{2 to} Rz ⁴ . Specifically, one side of the six-membered ring in formula (bd1) (the bond between the carbon atom to which Rz ¹ and Rz ² are bonded and the carbon atom to which Rz ³ and Rz ⁴ are bonded) is shared. ring structure, the ring structure in which a Rz ¹ and Rz ² formed by bonding, such as the ring structure can be mentioned where the Rz ³ and Rz ⁴ formed by the bonding.
The ring structure formed by two or more of Rz ¹ to Rz ⁴ may be an alicyclic hydrocarbon or an aromatic hydrocarbon, and is particularly an aromatic hydrocarbon. preferable. Further, this ring structure may be a polycyclic structure composed of other ring structures.

The alicyclic hydrocarbon formed by two or more of Rz ^{1 to} Rz ⁴ may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon, monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon, polycycloalkane is preferable. The polycycloalkane preferably has 7 to 30 carbon atoms, specifically, a polycycloalkane having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; A polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton is more preferable.
A heterocyclic structure in which a part of carbon atoms is substituted with a heteroatom may be used, and a nitrogen-containing heterocyclic ring is particularly preferable, and specific examples thereof include a cyclic imide.

The aromatic hydrocarbon ring formed by two or more of Rz ^{1 to} Rz ⁴ is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or a part of carbon atoms constituting these aromatic rings is a heteroatom. And substituted aromatic heterocycles. From the viewpoint of compatibility with the component (A), the aromatic hydrocarbon ring formed by two or more of Rz ^{1 to} Rz ⁴ preferably does not contain a hetero atom, and includes benzene, fluorene, naphthalene, anthracene, Aromatic rings such as phenanthrene and biphenyl are more preferred.

The ring structure (alicyclic hydrocarbon, aromatic hydrocarbon) formed by Rz ^{1 to} Rz ⁴ may have a substituent. The substituent herein, ^Rx 1 ^{to Rx} 4 described ^{above, Ry 1 ~Ry 2, Rz 1} ~Rz 4 cyclic substituents in group (e.g., alkyl group, alkoxy group, halogen atom, halogenated alkyl group , Hydroxyl group, nitro group, carbonyl group, etc.). Among them, as the substituent in the ring structure Rz ¹ ~Rz ⁴ is formed, in view of compatibility with component (A), an alkyl group, a halogen atom, such as a halogenated alkyl group and more preferably an alkyl group.

Among the ring structures formed by two or more of Rz ^{1 to} Rz ⁴ , the side of the six-membered ring in formula (bd1) (Rz ¹ and Rz ² ) is particularly preferable from the viewpoint of the controllability of the diffusion of acid generated by exposure. Is preferably a ring structure sharing a bond between the carbon atom to which Rz ³ and Rz ⁴ are bonded, and more preferably an aromatic ring structure.

In the formula (bd1), “when the valence allows” is as follows.
That is, when the bond between the carbon atom to which Rz ¹ and Rz ² are bonded and the carbon atom to which Rz ³ and Rz ⁴ are bonded is a single bond, Rz ¹ , Rz ² , Rz ³ and Rz All ^four are present. When the bond between the carbon atom to which Rz ¹ and Rz ² are bonded and the carbon atom to which Rz ³ and Rz ⁴ are bonded is a double bond, only ^one of Rz ¹ or Rz ² is present. And only one of Rz ³ and Rz ⁴ is present. For example, when Rz ¹ and Rz ³ are bonded to form an aromatic ring structure, Rz ² and Rz ⁴ do not exist.

In the formula (bd1), two or more of Rx ^{1 to} Rx ⁴ may be bonded to each other to form a ring structure. For example, Rx ¹ may form a ring structure with any of Rx ^{2 to} Rx ⁴ .
The ring structure formed by two or more of Rx ¹ to Rx ⁴ may be an alicyclic hydrocarbon or an aromatic hydrocarbon. Further, this ring structure may be a polycyclic structure composed of other ring structures.

The alicyclic hydrocarbon formed by two or more of Rx ^{1 to} Rx ⁴ may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon, monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon, polycycloalkane is preferable. The polycycloalkane preferably has 7 to 30 carbon atoms, specifically, a polycycloalkane having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane; A polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton is more preferable.

The aromatic hydrocarbon ring formed by two of Rx ^{1 to} Rx ⁴ is benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or a part of carbon atoms constituting these aromatic rings is substituted with a heteroatom. Aromatic heterocycles and the like. The aromatic hydrocarbon ring formed by two of Rx ^{1 to} Rx ⁴ preferably does not contain a heteroatom from the viewpoint of compatibility with the component (A), and includes benzene, fluorene, naphthalene, anthracene, phenanthrene. An aromatic ring such as biphenyl is more preferable.

The ring structure (alicyclic hydrocarbon, aromatic hydrocarbon) formed by Rx ^{1 to} Rx ⁴ may have a substituent. The substituent herein, ^Rx 1 ^{to Rx} 4 described ^{above, Ry 1 ~Ry 2, Rz 1} ~Rz 4 cyclic substituents in group (e.g., alkyl group, alkoxy group, halogen atom, halogenated alkyl group , Hydroxyl group, nitro group, carbonyl group, etc.). Among them, as the substituent in the ring structure Rx ¹ to Rx ⁴ is formed, in view of compatibility with component (A), an alkyl group, a halogen atom, such as a halogenated alkyl group and more preferably an alkyl group.

Among them, the ring structure formed by two or more of Rx ^{1 to} Rx ⁴ is preferably an alicyclic hydrocarbon from the viewpoint of acid diffusion controllability.
In addition, the ring structure formed by two or more of Rx ^{1 to} Rx ⁴ is, among other things, at least one of Rx ^{1 to} Rx ² and Rx ^{3 to} Rx ⁴ from the viewpoint of acid diffusion controllability. Of these, those in which at least one of them is bonded to each other to form a crosslinked ring structure are preferred, and those in which the ring structure is an alicyclic hydrocarbon are more preferred.

A bicyclic structure (Ry ¹ , Ry ²⁾ in the case where at least one of Rx ^{1 to} Rx ² and at least one of Rx ^{3 to} Rx ⁴ are bonded to each other to form a ring structure. , Rz ¹ and Rz ² , a ring structure including a carbon atom to which Rz ³ and Rz ⁴ are bonded, respectively, is preferably 7 to 16.

In the formula (bd1), at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part is an n-valent anion. n is an integer of 1 or more.
The component (BD1) is selected as an acid generator component (B) that generates an acid that acts on the base component (A) in the resist composition by selecting an anionic group in the molecule, or by exposure (B ) Acts as a base component (D) for trapping acid (controlling acid diffusion) generated from the component.
In the component (BD1), Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ may each be the anionic group. Alternatively, in the (BD1) component, when two or more of Rx ^{1 to} Rx ⁴ are bonded to each other to form a ring structure, the carbon atom forming the ring structure or the hydrogen atom bonded to the carbon atom May be substituted with the anionic group. If more than two of Ry ¹ to Ry ² are combined to form a ring structure with each other, a hydrogen atom bonded to a carbon atom or a carbon atom forming the ring structure is optionally substituted with the anionic group Also good. When two or more of Rz ^{1 to} Rz ⁴ are bonded to each other to form a ring structure, a carbon atom forming the ring structure or a hydrogen atom bonded to the carbon atom is substituted with the anion group. Also good.

Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ have anionic groups such as sulfonate anion structure, carboxylate anion structure, imide anion structure, methide anion structure, carbanion structure, borate anion structure, halogen Examples thereof include those having an anion structure, a phosphate anion structure, an antimonate anion structure, an arsenate anion structure, and the like. Among these, those having a sulfonate anion structure and those having a carboxylate anion structure are preferable.

Examples of the anionic group having an carboxylate anion ^{structure, * - V '- (.} 10 -COO V' 10 is a single bond or an alkylene group having 1 to 20 carbon atoms) are preferably exemplified.

Examples of the anionic group having the sulfonate anion structure include * -V ′ ¹¹ —SO ₃ ^— (V ′ ¹¹ is a single bond or an alkylene group having 1 to 20 carbon atoms) and the following general formula (bd1- An anionic group represented by r-an1) is preferred.
In the formula (bd1-r-an1), * represents a bond. * Means a bond with a carbon atom to which Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ are bonded.

［式中、Ｒ^ｂ０１は、炭素数１〜５のフッ素化アルキル基又はフッ素原子を表す。Ｖ^ｂ０１は、アルキレン基、フッ素化アルキレン基又は単結合を表す。Ｙ^ｂ０１は、２価の連結基又は単結合を表す。］

[Wherein, R ^b01 represents a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. V ^b01 represents an alkylene group, a fluorinated alkylene group, or a single bond. Y ^b01 represents a divalent linking group or a single bond. ]

In the formula (bd1-r-an1), R ^b01 represents a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. In R ^b01 , the C 1-5 perfluoroalkyl group is preferably a fluorine atom, and more preferably a fluorine atom.

In the formula (bd1-r-an1), V ^b01 represents an alkylene group, a fluorinated alkylene group, or a single bond.
The alkylene group and fluorinated alkylene group in V ^b01 each preferably have 1 to 4 carbon atoms, and more preferably 1 to 3 carbon atoms. ^Examples of the fluorinated alkylene group for V ^b01 include groups in which part or all of the hydrogen atoms of the alkylene group have been substituted with fluorine atoms. Especially, it is preferable that ^Vb01 is a C1- ^C4 alkylene group, a C1-C4 fluorinated alkylene group, or a single bond.

In the formula (bd1-r-an1), Y ^b01 represents a divalent linking group or a single bond.
Preferable examples of the divalent linking group for Y ^b01 include a divalent linking group containing an oxygen atom.
When Y ^b01 is a divalent linking group containing an oxygen atom, Y ^b01 may contain an atom other than an oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: —O—), an ester bond (—C (═O) —O—), and an oxycarbonyl group (—O—C (═O). )-), Amide bond (—C (═O) —NH—), carbonyl group (—C (═O) —), carbonate bond (—O—C (═O) —O—), etc. System oxygen atom-containing linking group; a combination of the non-hydrocarbon oxygen atom-containing linking group and an alkylene group. A sulfonyl group (—SO ₂ —) may be further linked to this combination.
Examples of the divalent linking group containing an oxygen atom include linking groups represented by the following general formulas (y-al-1) to (y-al-8), respectively.

［式中、Ｖ’^１０１は単結合または炭素数１〜５のアルキレン基であり、Ｖ’^１０２は炭素数１〜３０の２価の飽和炭化水素基である。］

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

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 an alkylene group having 1 to 5 carbon atoms. More preferably.

The alkylene group for V ′ ¹⁰¹ and V ′ ¹⁰² may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferred.
Specific examples of the alkylene group in V ′ ¹⁰¹ and V ′ ¹⁰² include a methylene group [—CH ₂ —]; —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as ethylene Groups [—CH ₂ CH ₂ —]; —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —CH (CH ₂ CH - ₃₎ CH ₂ alkyl groups such as, trimethylene group (n- propylene _{group) [- CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 -, - CH 2 CH (CH 3) CH ₂ - and the like alkyl trimethylene group; tetramethylene _{[-CH 2 CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 CH 2 - alkyl tetramethylene group and the like; pentamethylene group _{[-CH 2 CH 2 CH 2 CH} 2 CH 2 -] , and the like.
Moreover, some methylene groups in the alkylene group in V ′ ¹⁰¹ or V ′ ¹⁰² may be substituted with a C 5-10 divalent aliphatic cyclic group. The aliphatic cyclic group is preferably a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group.

Y ^b01 is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, each represented by the above formulas (y-al-1) to (y-al-6). A linking group is more preferred.

Specific examples of the anion group represented by the formula (bd1-r-an1) include, for example,
If Y ^b01 is a single ^{_{bond, -CH 2 CF 2 SO 3 -}} , -CF 2 CF 2 SO 3 -, and a fluorinated alkyl sulfonate anions such as trifluoromethane sulfonate anion or perfluorobutane sulfonate anion.
When ^Yb01 is a divalent linking group containing an oxygen atom, an anion represented by any of the following formulas (bd1-r-an11) to (bd1-r-an13) can be given.

［式中、Ｖ”^１０１は、単結合、炭素数１〜４のアルキレン基、又は炭素数１〜４のフッ素化アルキレン基である。Ｒ^１０２は、フッ素原子又は炭素数１〜５のフッ素化アルキル基である。ｖ”はそれぞれ独立に０〜３の整数である。ｑ”はそれぞれ独立に１〜２０の整数である。ｎ”は０または１である。］

[Wherein, V ″ ¹⁰¹ represents a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R ¹⁰² represents a fluorine atom or a fluorinated group having 1 to 5 carbon atoms. An alkyl group. V ″ is independently an integer of 0 to 3. q ″ is each independently an integer of 1 to 20. n ″ is 0 or 1. ]

In the formulas (bd1-r-an11) to (bd1-r-an13), V ″ ¹⁰¹ is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. V ″ ¹⁰¹ is preferably a single bond, an alkylene group having 1 carbon atom (methylene group), or a fluorinated alkylene group having 1 to 3 carbon atoms.

The formula (bd1-r-an11) ~ (bd1-r-an13), R 102 is a fluorine atom or a fluorinated alkyl group of 1 to 5 carbon atoms. In R ¹⁰² , the perfluoroalkyl group having 1 to 5 carbon atoms is preferably a fluorine atom, and more preferably a fluorine atom.

In the formulas (bd1-r-an11) to (bd1-r-an13), v ″ is an integer of 0 to 3, preferably 0 or 1.
q ″ is an integer of 1 to 20, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably 1, 2 or 3, particularly preferably 1 or 2. It is.
n ″ is 0 or 1, preferably 0.

The number of anionic groups in the component (BD1) may be one or two or more, and preferably one.
The (BD1) component becomes an n-valent anion in the entire anion part. n is an integer of 1 or more, preferably 1 or 2, and more preferably 1.

  The anion moiety in the component (BD1) is preferably an anion represented by the following general formula (bd1-an1) from the viewpoint of acid diffusion controllability.

［式中、Ｒｘ^５〜Ｒｘ^６はそれぞれ独立に、置換基を有してもよい炭化水素基又は水素原子を表す。Ｒｘ^７〜Ｒｘ^８は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。ｐは、１又は２であり、ｐ＝２の場合、複数のＲｘ^７〜Ｒｘ^８は相互に異なっていてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^５〜Ｒｘ^８、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。］

[Wherein, Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent. Rx ^{7 to} Rx ⁸ each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure. p is 1 or 2, and when p = 2, the plurality of Rx ⁷ to Rx ⁸ may be different from each other. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more. ]

In the formula (bd1-an1), Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom that may have a substituent. The hydrocarbon group which may have a substituent in Rx ^{5 to} Rx ⁶ is an explanation of the hydrocarbon group which may have a substituent in Rx ¹ to Rx ⁴ in the above formula (bd1). It is the same.

In the formula (bd1-an1), Rx ^{7 to} Rx ⁸ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or are bonded to each other to form a ring structure. May be. Such Rx ⁷ to Rx ⁸ are the same as those described for Rx ¹ to Rx ⁴ in the formula (bd1) described above.

In the formula (bd1-an1), p is 1 or 2, and when p = 2, the plurality of Rx ⁷ to Rx ⁸ may be different from each other. The anion represented by the general formula (bd1-an1) has a bicycloheptane ring structure when p = 1 and a bicyclooctane ring structure when p = 2.

In the formula (bd1-an1), Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or are bonded to each other to form a ring structure. May be. Such ^Ry 1 to Ry ² is the same as ^Ry 1 to Ry ² in the formula described above (bd1).
Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. Such ^Rz 1 ^{~Rz 4} is the same as ^Rz 1 ^{~Rz 4} in the formula described above (bd1).

However, in the formula (bd1-an1), at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and becomes an n-valent anion in the entire anion portion. . n is an integer of 1 or more.

  Among these, as the anion moiety in the component (BD1), from the viewpoint of acid diffusion controllability, an anion represented by p = 2 in the formula (bd1-an1), that is, the following general formula (bd1-an2) ) Is more preferable.

［式中、Ｒｘ^５〜Ｒｘ^６はそれぞれ独立に、置換基を有してもよい炭化水素基又は水素原子を表す。複数のＲｘ^７〜Ｒｘ^８は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^５〜Ｒｘ^８、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。］

[Wherein, Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent. A plurality of Rx ⁷ to Rx ⁸ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more may be bonded to each other to form a ring structure. . Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more. ]

In the formula (bd1-an2), Rx ^{5 to} Rx ⁶ , Rx ^{7 to} Rx ⁸ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ are the same as Rx ⁵ to Rx ⁶ , Rx in the formula (bd1) described above. ^{7 to} Rx ⁸ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ are the same.

However, in the formula (bd1-an2), at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and becomes an n-valent anion in the entire anion portion. . n is an integer of 1 or more.

In the formula (bd1), formula (bd1-an1), and formula (bd1-an2), Ry ^{1 to} Ry ² are mutually reduced in terms of shortening the diffusion of acid generated by exposure and controlling the diffusion of acid. The ring structure is preferably bonded to each other, and the formed ring structure is more preferably an aromatic hydrocarbon (aromatic ring, aromatic heterocycle) which may have a substituent.

In the formulas (bd1), (bd1-an1), and (bd1-an2), Rz ^{1 to} Rz ⁴ are bonded to each other to form a ring structure from the viewpoint of control of diffusion of the acid generated by exposure. Preferably, the ring structure is formed by one side of a six-membered ring in the formula (a carbon atom to which Rz ¹ and Rz ² are bonded, a carbon atom to which Rz ³ and Rz ⁴ are bonded) A ring structure that shares a bond of (A) and an aromatic hydrocarbon (aromatic ring, aromatic heterocyclic ring) that may have a substituent.

In the formulas (bd1-an1) and (bd1-an2), Rx ^{7 to} Rx ⁸ are bonded to each other from the viewpoint of shortening the diffusion of acid generated by exposure and controlling the diffusion of the acid to form a ring structure. Is preferably formed, and the ring structure formed is more preferably an aromatic hydrocarbon (aromatic ring, aromatic heterocyclic ring) which may have a substituent.
Ring structure formed in the formula ^(bd1-an2), in Rx 7 to Rx ⁸ is (bonds between the same carbon atom which Rx ⁷ and Rx ⁸ are attached) side of the six-membered ring in formula Share The ring structure is preferably an aromatic hydrocarbon (aromatic ring, aromatic heterocycle) which may have a substituent.

In each of the Rx ⁷ to Rx ⁸ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ^{4 in} the whole anion represented by the formula (bd1-an2), the number of ring structures formed by bonding to each other is One or two or more may be sufficient, and two or three are preferable.

  Particularly preferred examples of the anion moiety in the component (BD1) include anions represented by the following general formula (bd1-an3).

［式中、Ｒｘ^５〜Ｒｘ^６はそれぞれ独立に、置換基を有してもよい炭化水素基又は水素原子を表す。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^５〜Ｒｘ^６及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。Ｒ^０２１は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、カルボニル基又はニトロ基である。ｎ１は１〜３の整数である。ｎ１１は０〜８の整数である。Ｒ^０２２は、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、カルボニル基又はニトロ基である。ｎ２は１〜３の整数である。ｎ２１は０〜８の整数である。］

[Wherein, Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{5 to} Rx ⁶ and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more. R ⁰²¹ represents an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, or a nitro group. n1 is an integer of 1 to 3. n11 is an integer of 0-8. R ⁰²² is an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, or a nitro group. n2 is an integer of 1 to 3. n21 is an integer of 0-8. ]

In the formula ^{(bd1-an3), Rx 5} ~Rx 6, Rz 1 ~Rz 4 are respectively similar to the formula ^{(bd1-an1) Rx 5 ~Rx} 6, Rz 1 ~Rz 4 in.

In the formula (bd1-an3), R ⁰²¹ represents an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxy group, a carbonyl group, or a nitro group.
The alkyl group for R ⁰²¹ is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group for R ⁰²¹ is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. An ethoxy group is most preferred.
Examples of the halogen atom for R ⁰²¹ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
As the halogenated alkyl group for R ^021, a part or all of hydrogen atoms such as an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, Examples include groups substituted with atoms.
Among them, R ⁰²¹ is preferably an alkyl group, a halogen atom, a halogenated alkyl group, or the like, and more preferably an alkyl group, from the viewpoint of compatibility with the component (A).

In the formula (bd1-an3), n1 is an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.
In the formula (bd1-an3), n11 is an integer of 0 to 8, preferably an integer of 0 to 4, more preferably 0, 1 or 2, and particularly preferably 0 or 1.

In the formula (bd1-an3), R ⁰²² represents an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxy group, a carbonyl group, or a nitro group, and examples thereof are the same as those described above for R ^021. . Among these, R ⁰²² is preferably an alkyl group, a halogen atom, a halogenated alkyl group, or the like, and more preferably an alkyl group, from the viewpoint of compatibility with the component (A).
In the formula (bd1-an3), n2 is an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.
In said formula (bd1-an3), n21 is an integer of 0-8, Preferably it is an integer of 0-4, More preferably, it is 0, 1 or 2, Especially preferably, it is 0 or 1.

However, in the formula (bd1-an3), at least one of Rx ^{5 to} Rx ⁶ and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more.
Examples of the anionic group, described ^{above, * - V '- (.} 10 -COO V' 10 is a single bond or an alkylene group having 1 to 5 carbon atoms), is represented by the general formula (bd1-r-an1) Preferred examples thereof include anionic groups.

In the formula (bd1), formula (bd1-an1), formula (bd1-an2), and formula (bd1-an3), at least one of the Rz ^{1 to} Rz ⁴ is from the viewpoint of excellent effects of the present invention. It is preferable to have an anionic group. When two or more of Rz ^{1 to} Rz ⁴ are bonded to each other to form a ring structure, a carbon atom forming the ring structure or a hydrogen atom bonded to the carbon atom is substituted with the anion group. May be.

Alternatively, in the formula (bd1-an1), the formula (bd1-an2), and the formula (bd1-an3), at least one of the Rx ^{5 to} Rx ⁶ is an anionic group from the viewpoint of excellent effects of the present invention. It is preferable to have.

Alternatively, in the formula (bd1-an1), the formula (bd1-an2), and the formula (bd1-an3), at least ^{one of the} Rx ^{5 to} Rx ⁶ and Rz ^{1 to} Rz ⁴ from the viewpoint of excellent effects of the present invention. One preferably has an anionic group.

  Below, the specific example of the anion part in a compound (BD1) is described.

-About a cation part ((Mm ⁺ ) _{1 / m} ) In said formula (bd1), Mm ⁺ represents the m-valent organic cation which has an electron withdrawing group. m is an integer of 1 or more.

The electron withdrawing group possessed by the organic cation of M ^{m +} that is the cation moiety may be, for example, an electron withdrawing group of a monovalent substituent or an electron withdrawing group of a divalent substituent. Specifically, oxygen atom (—O—), carbonyl group, methanesulfonyl group (mesyl group), halogen atom, halogenated alkyl group, halogenated alkoxy group, halogenated aryloxy group, halogenated alkylamino group, halogen Alkylthio group, alkyloxycarbonyl group, aryloxycarbonyl group, cyano group, nitro group, dialkylphosphono group, diarylphosphono group, alkylsulfonyl group, arylsulfonyl group, sulfonyloxy group, acylthio group, sulfamoyl group, thiocyanate group And thiocarbonyl group.
The halogenated alkyl group is preferably a halogenated alkyl group having 1 to 10 carbon atoms. The halogenated alkyl group having 1 to 10 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 10 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 the above, from the viewpoint of high sensitivity, an oxygen atom (—O—), a carbonyl group, a methanesulfonyl group (mesyl group), a halogen atom or a halogenated alkyl group is preferable, and a halogen atom or a halogenated alkyl group is From the viewpoint of the solubility of the component (BD1) in the component (S) described later, it is more preferable. Among these, a fluorine atom and a fluorinated alkyl group are more preferable, and a fluorine atom and a trifluoromethyl group are particularly preferable.

When the electron withdrawing group is a fluorine atom or a fluorinated alkyl group, the number of fluorine atoms in the cation moiety ((M ^{m +} ) _{1 / m} ) is preferably 1 to 9, and 2 to 6 It is more preferable that the number is 3 or 4.
As the number of fluorine atoms increases, the sensitivity becomes better. However, if the fluorine atom is not more than the upper limit of the preferable range, the compatibility with each component of the resist composition is maintained, and the occurrence of roughness is easily suppressed.

As the organic cation of M ^{m +} , a sulfonium cation and an iodonium cation are preferable. Moreover, when using (BD1) component as a base component (D), an ammonium cation is also mentioned.

Preferable cation moieties ((M ^{m +} ) _{1 / m} ) include organic cations represented by the following general formulas (ca-1) to (ca-4), respectively.

［式中、Ｒ^２０１〜Ｒ^２０７及びＲ^２１１〜Ｒ^２１２はそれぞれ独立に、置換基を有してもよいアリール基、置換基を有してもよいアルキル基、又は置換基を有してもよいアルケニル基を表す。Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２はそれぞれ、相互に結合して式中のイオウ原子と共に環を形成していてもよい。Ｒ^２０８〜Ｒ^２０９は、それぞれ独立に、水素原子もしくは炭素数１〜５のアルキル基を表すか、又は相互に結合して式中のイオウ原子と共に環を形成していてもよい。Ｒ^２１０は、置換基を有してもよいアリール基、置換基を有してもよいアルキル基、置換基を有してもよいアルケニル基、又は置換基を有してもよい−ＳＯ_２−含有環式基である。但し、Ｒ^２０１〜Ｒ^２０３のうち少なくとも１個、Ｒ^２０４及びＲ^２０５のうち少なくとも１個、Ｒ^２０６及びＲ^２０７のうち少なくとも１個、並びにＲ^２１１及びＲ^２１２のうち少なくとも１個は、置換基として電子求引性基を有する。Ｌ^２０１は、−Ｃ（＝Ｏ）−又は−Ｃ（＝Ｏ）−Ｏ−を表す。複数のＹ^２０１はそれぞれ独立に、アリーレン基、アルキレン基又はアルケニレン基を表す。ｘは、１又は２である。Ｗ^２０１は、（ｘ＋１）価の連結基を表す。］

[Wherein, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² each independently have an aryl group which may have a substituent, an alkyl group which may have a substituent, or a substituent. Represents a good alkenyl group. R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ , and R ^{211 to} R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, or may be bonded to each other to form a ring together with the sulfur atom in the formula. R ²¹⁰ may have an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or —SO ₂ — that may have a substituent. It is a containing cyclic group. Provided ^that at least one of R 201 ^{to R 203,} at least one of ^{R 204} and ^{R 205,} at least one of ^{R 206} and ^{R 207,} as well as at least one of ^{R 211} and ^{R 212} are substituents As an electron withdrawing group. L ²⁰¹ represents —C (═O) — or —C (═O) —O—. A plurality of Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group. x is 1 or 2. W ²⁰¹ represents a (x + 1) -valent linking group. ]

As the aryl group in R ²⁰¹ to R ²⁰⁷ and ^R 211 ^{to R 212,} include an aryl group having 6 to 20 carbon atoms, a phenyl group, a naphthyl group.
The alkyl group of R ²⁰¹ to R ²⁰⁷ and ^R 211 ^{to R 212,} a chain or cyclic alkyl group, preferably from 1 to 30 carbon atoms.
The alkenyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² preferably has 2 to 10 carbon atoms.
Examples of the substituent that R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and the following general groups. And groups represented by formulas (ca-r-1) to (ca-r-7), respectively.

［式中、Ｒ’^２０１は、それぞれ独立に、水素原子、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。］

[Wherein, each R ′ ²⁰¹ independently has a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. A chain alkenyl group which may be present. ]

The cyclic group which may have a substituent of R ′ ^201, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent are the above-mentioned. of formula (bd1) ^Rx 1 ~Rx 4 ^in, Ry ^{1 ~Ry 2,} Rz ¹ except that is the same as those described description of ~Rz ^4, good cyclic group or a substituted may have a substituent Examples of the chain-like alkyl group that may have a group include the same acid dissociable groups represented by the above formula (a1-r-2).

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 201 ~R 203, R 206 ~R} 207, R 211 ~R 212 , when bonded to each other to form a ring with the sulfur atom, a sulfur atom, an oxygen atom, or a hetero atom such as nitrogen atom, carbonyl _{group, -SO -, - SO 2 -} , - SO 3 -, - COO -, - CONH- , or -N _(R N) - (. the _{R N} is an alkyl group having 1 to 5 carbon atoms), etc. You may couple | bond through the functional group of. As the ring to be formed, one ring containing a sulfur atom in the ring skeleton in the formula is preferably a 3- to 10-membered ring, particularly a 5- to 7-membered ring, including the sulfur atom. preferable. Specific examples of the ring formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, thianthrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thioxanthene ring, thioxanthone ring, thianthrene ring, phenoxathiin ring, tetrahydro A thiophenium ring, a tetrahydrothiopyranium ring, etc. are mentioned.

R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable. A ring may be formed together with the sulfur atom in the formula.

R ²¹⁰ may have an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or —SO ₂ — that may have a substituent. It is a containing cyclic group.
^Examples of the aryl group for R ²¹⁰ include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group for R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group for R ²¹⁰ preferably has 2 to 10 carbon atoms.
Table is preferably the general formula (a5-r-1) The content cyclic group, - at R ^210, which may have -SO ₂ substituents "- containing polycyclic group - SO _2" More preferred are the groups

Provided ^that at least one of R 201 ^{to R 203,} at least one of ^{R 204} and ^{R 205,} at least one of ^{R 206} and ^{R 207,} as well as at least one of ^{R 211} and ^{R 212} are substituents As an electron withdrawing group.
Here, having an electron withdrawing group as a substituent means an aryl group or an alkyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² in the above general formulas (ca-1) to (ca-4). Alternatively, it means that an electron-withdrawing group is bonded to the alkenyl group as a substituent. In addition, when each of R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ , and R ^{211 to} R ²¹² is bonded to each other to form a ring with the sulfur atom in the formula, the ring structure has an electron withdrawing property. Has a group.

Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group.
The arylene group in Y ²⁰¹ further has one hydrogen atom from the aryl group exemplified as the aromatic hydrocarbon group in Rx ¹ to Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ in the above formula (bd1). Excluded groups are mentioned.
The alkylene group and alkenylene group in Y ²⁰¹ are exemplified as the chain alkyl group and the chain alkenyl group in Rx ¹ to Rx ⁴ , Ry ^{1 to} Ry ² , and Rz ^{1 to} Rz ⁴ in the above formula (bd1). And a group obtained by further removing one hydrogen atom from the group.

In the formula (ca-4), x is 1 or 2.
W ²⁰¹ is a (x + 1) valent, that is, a divalent or trivalent linking group.
The divalent linking group in W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, and has the same substituent as Ya ^x1 in the above general formula (a10-1). Examples thereof may include divalent hydrocarbon groups. The divalent linking group in W ²⁰¹ may be linear, branched or cyclic, and is preferably cyclic. Of these, a group in which two carbonyl groups are combined at both ends of the arylene group is preferable. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.
^Examples of the trivalent linking group in W ²⁰¹ include a group obtained by removing one hydrogen atom from the divalent linking group in W ²⁰¹ , a group in which the divalent linking group is further bonded to the divalent linking group, and the like. Can be mentioned. The trivalent linking group for W ²⁰¹ is preferably a group in which two carbonyl groups are bonded to an arylene group.

  Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following formulas (ca-1-1) to (ca-1-78).

［式中、ｇ１は繰返し数を示し、ｇ１は１〜５の整数である。］

[Wherein g1 represents the number of repetitions, and g1 is an integer of 1 to 5. ]

［式中、ｇ２は繰返し数を示し、ｇ２は０〜２０の整数である。］

[Wherein g2 represents the number of repetitions, and g2 is an integer of 0 to 20. ]

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

  Specific examples of suitable cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-7), respectively.

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

In addition, as the ammonium cation when the component (BD1) is used as the base component (D), NH ₄ ⁺ or a cation in which H bonded to the nitrogen atom is substituted with a hydrocarbon group that may have a hetero atom (Primary to quaternary ammonium cation) or a cyclic cation that forms a ring with its nitrogen atom.

Among these, the cation part ((M ^{m +} ) _{1 / m} ) is preferably a cation represented by the general formula (ca-1), and each represented by the formulas (ca-1-1) to (ca-1-78). The represented cation is more preferred.
Among these, a cation in the case where one or more of R ^{201 to} R ^{203 in} the general formula (ca-1) is an aryl group having an electron withdrawing group as a substituent is more preferable. Further, a cation in the case of an aryl group having an electron withdrawing group at the meta position as a substituent is more preferable. The electron withdrawing group is preferably a halogen atom or a halogenated alkyl group, more preferably a fluorine atom or a fluorinated alkyl group. Specifically, cations represented by the above formulas (ca-1-1) to (ca-1-17) and (ca-1-18) to (ca-1-20) are preferable. The above formulas (ca-1-5) to (ca-1-9), (ca-1-12) to (ca-1-14), and (ca-1-18) to (ca-1) Cations represented by -19) are more preferred.

Among the above-described components (BD1), the acid generator component (B) that generates an acid acting on the component (A) (hereinafter also referred to as “component (B1)”) is the above-described formula (bd1). -An1) to (bd1-an3), which are anion groups represented by the general formula (bd1-r-an1) (more preferably, the formulas (bd1-r-an11) to (bd1- an anion group represented by any one of r-an13) (more preferably, an anion represented by any one of (bd1-an3-1) to (bd1-an3-15)),
Cations represented by formulas (ca-1) to (ca-4) (more preferably (ca-1-1) to (ca-1-78), (ca-2-1) to (ca-2) -2), (ca-3-1) to (ca-3-7), and (ca-4-1) to (ca-4-2) cations) and various combinations thereof Can be mentioned. Specific examples of the component (B1) are shown below, but are not limited thereto.

In the resist composition of this embodiment, as the component (B1), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present embodiment, the content of the component (B1) is preferably 5 to 65 parts by mass and more preferably 5 to 55 parts by mass with respect to 100 parts by mass of the component (A). Preferably, it is 10-45 mass parts, More preferably, it is 10-40 mass parts.
In the resist composition, the ratio of the component (B1) is 50% by mass or more, preferably 70% by mass, out of the total acid generator component (B) component that generates acid acting on the component (A). % Or more, and more preferably 95% by mass or more. In addition, 100 mass% may be sufficient.
When the content of the component (B1) is equal to or higher than the lower limit of the above preferable range, lithography characteristics such as sensitivity, resolution performance, LWR (line width roughness) reduction, and shape are further improved in resist pattern formation. On the other hand, when it is not more than the upper limit of the preferred range, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, and the storage stability as the resist composition is further increased.
In addition, when the resist composition contains both the component (B1) and the component (D) (at least one of the components (D1) to (D3)), the ratio (molar ratio) is such that good lithography characteristics and resist For example, (B1) :( D) = 100: 0 to 50:50, (B1) :( D) = 99: 1 to 51:49 is more preferable, and (B1): ) :( D) = 90: 10 to 60:40 is more preferable.

In addition, among the components (BD1) described above, the base component (D) that traps the acid generated from the component (B) upon exposure (controls the diffusion of the acid) (hereinafter also referred to as “component (D1)”). Is an anion represented by any one of the formulas (bd1-an1) to (bd1-an3) described above, and * -V ′ ¹⁰ —COO ⁻ (V ′ ¹⁰ is a single bond or a carbon number of 1 Or an anionic group having an anionic group represented by * —V ′ ¹¹ —SO ₃ ^— (V ′ ¹¹ is a single bond or an alkylene group having 1 to 20 carbon atoms). (More preferably, an anion represented by any one of formulas (bd1-an3-21) to (bd1-an3-24)) and any one of formulas (ca-1) to (ca-4). Cations (more preferably, the formula (ca-1- ) To (ca-1-78), (ca-1-101) to (ca-1-169), (ca-2-1) to (ca-2-2), (ca-3-1) to Various combinations of (ca-3-7) and (cation represented by any one of (ca-4-1) to (ca-4-2)) can be given. Specific examples of the component (D1) are shown below, but are not limited thereto.
Specific examples of suitable compounds are listed below.

In the resist composition of this embodiment, as the component (D1), one type may be used alone, or two or more types may be used in combination.
In the resist composition of this embodiment, the content of the component (D1) is preferably 1 to 35 parts by weight, more preferably 2 to 25 parts by weight, and 3 to 20 parts by weight with respect to 100 parts by weight of the component (A). Part is more preferable, and 4 to 15 parts by mass is particularly preferable.
In the resist composition, the ratio of the component (D1) in the base component (D) component that traps the acid generated from the component (B) upon exposure (controls the diffusion of the acid) is, for example, 50% by mass or more. Preferably, it is 70 mass% or more, More preferably, it is 95 mass% or more. In addition, 100 mass% may be sufficient. In addition, the ratio of the said (D1) component in the whole (D) component in case a resist composition contains (B1) component is not specifically limited, If it adjusts in the range of 0 mass% or more and 100 mass% suitably. Good.
When the content of the component (D1) is not less than the lower limit value of the preferred range, good lithography characteristics and a resist pattern shape are easily obtained. On the other hand, when it is not more than the upper limit value of the preferable range, it is possible to balance with other components, and various lithography characteristics are improved.
Further, when the resist composition contains both the component (D1) and the component (B) (at least one of the components (B1) to (B2)), the ratio (molar ratio) is such that good lithography characteristics and resist For example, (B) :( D1) = 100: 0 to 50:50, and (B) :( D1) = 99: 1 to 51:49 is more preferable because the pattern shape is easily obtained. ): (D1) = 90: 10 to 60:40 is more preferable.

<Optional component>
The resist composition of this embodiment may further contain components (arbitrary components) other than the above-described component (A) and compound (BD1) (component (B1), component (D1)).
Examples of such optional components include the following (B2) component, (D2) component, (D3) component, (E) component, (F) component, and (S) component.

≪ (B2) component≫
The resist composition of this embodiment may contain an acid generator component (hereinafter referred to as “component (B2)”) other than the component (B1) as long as the effects of the present invention are not impaired.
The component (B2) is not particularly limited, and any component that has been proposed as an acid generator for a chemically amplified resist composition can be used.
Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators; diazomethanes such as bisalkyl or bisarylsulfonyldiazomethanes and poly (bissulfonyl) diazomethanes Acid generators: various types such as nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  Examples of the onium salt acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as “(b-1) component”) and a general formula (b-2). Examples thereof include a compound (hereinafter also referred to as “(b-2) component”) or a compound represented by the general formula (b-3) (hereinafter also referred to as “(b-3) component”). In addition, (b-1) component shall not contain the compound applicable to the above-mentioned (B1) component.

［式中、Ｒ^１０１、Ｒ^１０４〜Ｒ^１０８はそれぞれ独立に、置換基を有してもよい環式基、置換基を有してもよい鎖状のアルキル基、又は置換基を有してもよい鎖状のアルケニル基である。Ｒ^１０４、Ｒ^１０５は、相互に結合して環を形成していてもよい。Ｒ^１０２はフッ素原子又は炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合、又は酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基又はフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合又は酸素原子である。Ｌ^１０３〜Ｌ^１０５はそれぞれ独立に単結合、−ＣＯ−又は−ＳＯ_２−である。ｍは１以上の整数であって、Ｍ’^ｍ＋はｍ価のオニウムカチオンである。］

[In the formula, each of R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ independently has a cyclic group that may have a substituent, a chain alkyl group that may have a substituent, or a substituent. It is also a good chain alkenyl group. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. R ¹⁰² represents a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ^{101 to} L ¹⁰² are each independently a single bond or an oxygen atom. L ^{103 to} L ¹⁰⁵ are each independently a single bond, —CO— or —SO ₂ —. m is an integer of 1 or more, and M ′ ^{m +} is an m-valent onium cation. ]

{Anion part}
-Anion moiety of component (b-1) In formula (b-1), R ¹⁰¹ represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. A chain alkenyl group which may have a group. The description of R ¹⁰¹ is substitution in Rx ¹ to Rx ⁴ , Ry ^{1 to} Ry ² , Rz ^{1 to} Rz ⁴ (hereinafter referred to as “Rx ^{1 to} Rx ⁴ etc.”) in the formula (bd1). A hydrocarbon group which may have a group (a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl which may have a substituent) This is the same as the explanation for the group.
Among these, R ¹⁰¹ is preferably a cyclic group that may have a substituent, and more preferably a cyclic hydrocarbon group that may have a substituent. More specifically, a group obtained by removing one or more hydrogen atoms from a phenyl group, a naphthyl group, or a polycycloalkane; the general formulas (a2-r-1), (a2-r-3) to (a2-r) The lactone-containing cyclic group represented by -7); the —SO ₂ -containing cyclic group represented by the general formulas (a5-r-1) to (a5-r-4), respectively, and the like are preferable.

In said formula (b-1), ^Y101 is a bivalent coupling group containing a single bond or an oxygen atom.
When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, Y ¹⁰¹ may contain an atom other than an oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include linking groups represented by the general formulas (y-al-1) to (y-al-8), respectively.
Y ¹⁰¹ is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, each represented by the above general formulas (y-al-1) to (y-al-5). More preferred is a linking group.

In said formula (b-1), ^V101 is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group for V ¹⁰¹ preferably have 1 to 4 carbon atoms. ^Examples of the fluorinated alkylene group for V ¹⁰¹ include groups in which some or all of the hydrogen atoms of the alkylene group for V ¹⁰¹ have been substituted with fluorine atoms. Among ^{them, V 101} is preferably a single bond, or a fluorinated alkylene group having 1 to 4 carbon atoms.

In said formula (b-1), ^R102 is a fluorine atom or a C1-C5 fluorinated alkyl group. R ¹⁰² is preferably a fluorine atom or a C 1-5 perfluoroalkyl group, and more preferably a fluorine atom.

(B-1) Specific examples of the anion moiety of the component, for example, if the Y ¹⁰¹ is a single bond, fluorinated alkyl sulfonate anions such as trifluoromethane sulfonate anion or perfluorobutane sulfonate anion can be exemplified; Y ¹⁰¹ is In the case of a divalent linking group containing an oxygen atom, anions represented by any one of the following formulas (an-1) to (an-3) can be mentioned.

［式中、Ｒ”^１０１は、置換基を有してもよい脂肪族環式基、上記の化学式（ｒ−ｈｒ−１）〜（ｒ−ｈｒ−６）でそれぞれ表される１価の複素環式基、又は置換基を有してもよい鎖状のアルキル基である。Ｒ”^１０２は、置換基を有してもよい脂肪族環式基、前記一般式（ａ２−ｒ−１）、（ａ２−ｒ−３）〜（ａ２−ｒ−７）でそれぞれ表されるラクトン含有環式基、又は前記一般式（ａ５−ｒ−１）〜（ａ５−ｒ−４）でそれぞれ表される−ＳＯ_２−含有環式基である。Ｒ”^１０３は、置換基を有してもよい芳香族環式基、置換基を有してもよい脂肪族環式基、又は置換基を有してもよい鎖状のアルケニル基である。Ｖ”^１０１は、炭素数１〜４のアルキレン基、又は炭素数１〜４のフッ素化アルキレン基である。Ｒ^１０２は、フッ素原子又は炭素数１〜５のフッ素化アルキル基である。ｖ”はそれぞれ独立に０〜３の整数であり、ｑ”はそれぞれ独立に１〜２０の整数であり、ｎ”は０または１である。］

[Wherein R ″ ¹⁰¹ represents an aliphatic cyclic group which may have a substituent, and a monovalent complex represented by each of the above-described chemical formulas (r-hr-1) to (r-hr-6). A cyclic group or a chain-like alkyl group which may have a substituent. R ″ ¹⁰² may be an aliphatic cyclic group which may have a substituent, the above-mentioned general formula (a2-r-1) , A lactone-containing cyclic group represented by (a2-r-3) to (a2-r-7), respectively, or the general formula (a5-r-1) to (a5-r-4). -SO ₂ -containing cyclic group. 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 an alkylene group having 1 to 4 carbon atoms or a fluorinated alkylene group having 1 to 4 carbon atoms. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. v ″ is independently an integer of 0 to 3, q ″ is independently an integer of 1 to 20, and n ″ is 0 or 1.]

The aliphatic cyclic group which may have a substituent of R ″ ¹⁰¹ , R ″ ¹⁰² and R ″ ¹⁰³ is exemplified as the cyclic aliphatic hydrocarbon group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1) Examples of the substituent include the same substituents that may be substituted for the cyclic aliphatic hydrocarbon group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1). .

The aromatic cyclic group which may have a substituent in R ″ ¹⁰³ is the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1). Examples of the substituent include the same substituents that may substitute the aromatic hydrocarbon group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1).

The chain alkyl group which may have a substituent in R ″ ¹⁰¹ is preferably a group exemplified as the chain alkyl group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1). ^The chain alkenyl group which may have a substituent in ¹⁰³ is preferably a group exemplified as the chain alkenyl group in Rx ¹ to Rx ^{4 and the} like in the formula (bd1).

-Anion part of component (b-2) In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group which may have a substituent or a chain which may have a substituent. A cyclic alkyl group, or a chain alkenyl group which may have a substituent, each having a substituent in Rx ¹ to Rx ⁴ etc. in the formula (bd1) And a chain alkyl group which may have a substituent, or a chain alkyl group which may have a substituent. 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, and may be a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. Is more preferable.
The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and still more preferably 1 to 3 carbon atoms. The number of carbon atoms of the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible because the solubility in a resist solvent is good within the range of the carbon number. In the chain alkyl groups of R ¹⁰⁴ and R ^105, the larger the number of hydrogen atoms substituted with fluorine atoms, the more preferable the strength of the acid. 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 all hydrogen atoms are substituted with fluorine atoms. Perfluoroalkyl group.
In formula (b-2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each of them is the same as V ¹⁰¹ in formula (b-1). Can be mentioned.
In formula (b-2), L ¹⁰¹ and L ¹⁰² each independently represent a single bond or an oxygen atom.

-Anion part of component (b-3) In formula (b-3), R ^{106 to} R ¹⁰⁸ are each independently a cyclic group which may have a substituent or a chain which may have a substituent. A cyclic alkyl group, or a chain alkenyl group which may have a substituent, each having a substituent in Rx ¹ to Rx ^{4 and the} like in the formula (bd1) And a chain alkyl group which may have a substituent, or a chain alkyl group which may have a substituent.
L ^{103 to} L ¹⁰⁵ are each independently a single bond, —CO— or —SO ₂ —.

{Cation part}
In the formulas (b-1), (b-2), and (b-3), m is an integer of 1 or more, M ′ ^{m +} is an m-valent onium cation, and a sulfonium cation and an iodonium cation are preferable. For example, organic cations represented by the above formulas (ca-1-1) to (ca-1-78), respectively, and the following formulas (ca-1-101) to (ca-1-149) Organic cations represented respectively.

［式中、ｇ３は繰返し数を示し、ｇ３は０〜２０の整数である。］

[Wherein g3 represents the number of repetitions, and g3 is an integer of 0 to 20. ]

［式中、Ｒ”^２０１は水素原子又は置換基である。該置換基としては、上記Ｒ^２０１〜Ｒ^２０７およびＲ^２１１〜Ｒ^２１２が有してもよい置換基として挙げた、アルキル基、ハロゲン原子、ハロゲン化アルキル基、カルボニル基、シアノ基、アミノ基、アリール基、一般式（ｃａ−ｒ−１）〜（ｃａ−ｒ−７）でそれぞれ表される基が挙げられる。］

[Wherein, R ″ ²⁰¹ is a hydrogen atom or a substituent. Examples of the substituent include the alkyl groups and halogens mentioned as the substituents that R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² may have. Examples thereof include an atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and groups represented by general formulas (ca-r-1) to (ca-r-7).

In addition, as M ′ ^{m +} in the formulas (b-1), (b-2), and (b-3), diphenyliodonium cation, bis (4-tert-butylphenyl) iodonium cation, the above formula (ca-3) -1) to (ca-3-7), and cations represented by the above formulas (ca-4-1) to (ca-4-2).
Among them, the cation part [(M ′ ^{m +} ) _{1 / m} ] is an organic cation represented by the formulas (ca-1-1) to (ca-1-78), respectively, and the formula (ca-1-101). The organic cation represented by each of (ca-1-149) is more preferable.

In the resist composition of this embodiment, as the component (B2), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (B2), the content of the component (B2) in the resist composition is preferably 50 parts by mass or less, and 1 to 40 parts by mass with respect to 100 parts by mass of the component (A). Is more preferable, and 5-30 mass parts is further more preferable.
Further, when the resist composition contains the component (B2), the content of the component (B2) in the entire acid generator component (B) that generates an acid acting on the component (A) in the resist composition is For example, it is 50 mass% or less, 30 mass% or less is more preferable, and 0 mass% or more and 5 mass% or less are more preferable. In addition, the ratio of the said (B2) component in the whole (B) component in case a resist composition contains (D1) component is not specifically limited, If it adjusts suitably in the range of 0 mass% or more and 100 mass%. Good.
By forming the content of the component (B2) within the above range, pattern formation is sufficiently performed. Moreover, when each component of a resist composition is melt | dissolved in the organic solvent, since a uniform solution is easy to be obtained and the storage stability as a resist composition becomes favorable, it is preferable.

≪ (D2) component≫
The component (D2) is a base component and is a photodegradable base that is decomposed by exposure and loses acid diffusion controllability (excluding those corresponding to the component (D1) above).
By forming the resist composition containing the component (D2), the contrast between the exposed portion and the unexposed portion of the resist film can be further improved when forming a resist pattern.

The component (D2) is not particularly limited as long as it is decomposed by exposure and loses acid diffusion controllability. And a compound represented by the following general formula (d2-2) (hereinafter referred to as “(d2-2) component”) and a compound represented by the following general formula (d2-3) (hereinafter referred to as “(d2- One or more compounds selected from the group consisting of “3) component”) are preferred.
The components (d2-1) to (d2-3) are decomposed in the exposed portion of the resist film and lose acid diffusion controllability (basicity), and therefore do not act as a quencher. Acts as

［式中、Ｒｄ^１〜Ｒｄ^４は置換基を有してもよい環式基、置換基を有してもよい鎖状のアルキル基、又は置換基を有してもよい鎖状のアルケニル基である。但し、一般式（ｄ２−２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子にはフッ素原子が結合していないものとする。Ｙｄ^１は単結合又は２価の連結基である。ｍは１以上の整数であって、Ｍ’^ｍ＋はそれぞれ独立にｍ価のオニウムカチオンである。］

[Wherein Rd ^{1 to} Rd ⁴ are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. It is. However, a fluorine atom is not bonded to a carbon atom adjacent to the S atom in Rd ² in the general formula (d2-2). Yd ¹ is a single bond or a divalent linking group. m is an integer of 1 or more, and M ′ ^{m +} is each independently an m-valent onium cation. ]

{(D2-1) component}
· During anion formula (d2-1), Rd ^1, the substituents cyclic group which may have a may have a substituent which may chain having alkyl group, or a substituent Examples of the chain alkenyl group include those similar to Rx ¹ to Rx ⁴ in the formula (bd1).
Among these, as Rd ¹ , an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain which may have a substituent Alkyl groups are preferred. Examples of the substituent 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 the above general formulas (a2-r-1) to (a2-r-7). ) -Containing cyclic groups, ether bonds, ester bonds, or combinations thereof. When an ether bond or an ester bond is included as a substituent, an alkylene group may be interposed. In this case, the substituent is represented by the above formulas (y-al-1) to (y-al-5), respectively. The linking group is preferred.
Preferable examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (for example, a polycyclic structure composed of a bicyclooctane skeleton and another ring structure). It is done.
The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane.
The chain alkyl group preferably has 1 to 10 carbon atoms, specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, Linear alkyl groups such as nonyl and decyl; 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl A branched alkyl group such as a group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group.

When the chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms. ~ 4 is more preferred. The fluorinated alkyl group may contain an atom other than a fluorine atom. Examples of atoms other than fluorine atoms include oxygen atoms, sulfur atoms and nitrogen atoms.
Rd ¹ is preferably a fluorinated alkyl group in which part or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms, and the hydrogen atom constituting the linear alkyl group It is particularly preferred that all are fluorinated alkyl groups (linear perfluoroalkyl groups) substituted with fluorine atoms.

  Preferred specific examples of the anion moiety of the component (d2-1) are shown below.

-Cation part In Formula (d2-1), M'm ⁺ is an m-valent onium cation.
'The ^{m +} onium cation, (D1) as different from the components, the formula (b-1) ~ (b -3) in M' M can be appropriately selected from among ^{m +} and the like.
As the component (d2-1), one type may be used alone, or two or more types may be used in combination.

{(D2-2) component}
Anion formula (d2-2), Rd ^2, the substituents cyclic group which may have a may have a substituent which may chain having alkyl group, or a substituent Examples of the chain alkenyl group include those similar to Rx ¹ to Rx ⁴ in the formula (bd1).
However, a fluorine atom is not bonded to a carbon atom adjacent to the S atom in Rd ² (not fluorine-substituted). Thereby, the anion of (d2-2) component turns into a moderate weak acid anion, and the quenching ability as (D2) component improves.
Rd ² is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent. The chain alkyl group preferably has 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. As the aliphatic cyclic group, a group in which one or more hydrogen atoms are removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (which may have a substituent); one or more from camphor, etc. It is more preferable that it is a group from which a hydrogen atom is removed.
The hydrocarbon group of Rd ² may have a substituent, and examples of the substituent include a hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain in Rd ¹ of the formula (d2-1)). And the same substituents that the alkyl group may have).

  Preferred specific examples of the anion moiety of the component (d2-2) are shown below.

-Cation part In formula (d2-2), M'm ⁺ is an m-valent onium cation, and is the same as M'm ⁺ in formula (d2-1).
As the component (d2-2), one type may be used alone, or two or more types may be used in combination.

{(D2-3) component}
Anion moiety In formula (d2-3), Rd ³ is a cyclic group that may have a substituent, a chain alkyl group that may have a substituent, or a chain that may have a substituent. A alkenyl group having the same shape as Rx ¹ to Rx ⁴ in the formula (bd1), which is a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. It is preferable. Among them, a fluorinated alkyl group is preferable, and the same as the fluorinated alkyl group for Rd ¹ is more preferable.

In formula (d2-3), Rd ⁴ represents a cyclic group that may have a substituent, a chain alkyl group that may have a substituent, or a chain that may have a substituent. Examples of the alkenyl group include those similar to Rx ¹ to Rx ⁴ in the formula (bd1).
Among these, an alkyl group, an alkoxy group, an alkenyl group, or a cyclic group which may have a substituent is preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group. Tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of 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 in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms. Specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Examples thereof include a butoxy group and a tert-butoxy group. Of these, a methoxy group and an ethoxy group are preferable.

Examples of the alkenyl group in Rd ⁴ include those similar to Rx ¹ to Rx ⁴ and the like in the formula (bd1). preferable. These groups may further have, as a substituent, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

Examples of the cyclic group in Rd ⁴ include the same groups as those in Rx ¹ to Rx ⁴ in the formula (bd1). Cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like An alicyclic group obtained by removing one or more hydrogen atoms from an alkane, 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 well dissolved in an organic solvent, whereby the lithography properties are improved.

In formula (d2-3), Yd ¹ represents a single bond or a divalent linking group.
The divalent linking group in Yd ¹ is not particularly limited, but may be a divalent hydrocarbon group (aliphatic hydrocarbon group or aromatic hydrocarbon group) which may have a substituent, or a divalent group containing a hetero atom. And the like. Each of these includes a divalent hydrocarbon group which may have a substituent and a hetero atom which are mentioned in the description of the divalent linking group in Ya ^x1 in the formula (a10-1). The thing similar to a valent coupling group is mentioned.
Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is preferably a linear or branched alkylene group, and more preferably a methylene group or an ethylene group.

  Preferred specific examples of the anion moiety of the component (d2-3) are shown below.

-Cation part In formula (d2-3), M'm ⁺ is an m-valent onium cation, and is the same as M'm ⁺ in formula (d2-1).
As the component (d2-3), one type may be used alone, or two or more types may be used in combination.

As the component (D2), only one of the above components (d2-1) to (d2-3) may be used, or two or more may be used in combination.
When the resist composition contains the component (D2), the content of the component (D2) in the resist composition is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the component (A). 5-8 mass parts is more preferable, and 1-6 mass parts is further more preferable.
In addition, when the resist composition contains the component (D2), among the entire base component (D) that traps (controls the diffusion of the acid) the acid generated from the component (B) by exposure in the resist composition, ( The content of the component D2) is, for example, 50% by mass or less, more preferably 30% by mass or less, and further preferably 0% by mass or more and 5% by mass or less. In addition, the ratio of the said (D2) component in the whole (D) component in case a resist composition contains (B1) component is not specifically limited, If it adjusts suitably in 0 mass% or more and 100 mass%. Good.
When the content of the component (D2) is not less than the lower limit value of the preferable range, particularly good lithography characteristics and a resist pattern shape are easily obtained. On the other hand, when the amount is not more than the upper limit of the above preferable range, a balance with other components can be achieved, and various lithography characteristics are improved.

(D2) Component production method:
The manufacturing method of said (d2-1) component and (d2-2) component is not specifically limited, It can manufacture by a well-known method.
Moreover, the manufacturing method of (d2-3) component is not specifically limited, For example, it manufactures similarly to the method of US2012-0149916 gazette.

≪ (D3) component≫
The component (D3) is a basic component and a nitrogen-containing organic compound component that acts as an acid diffusion controller in the resist composition (except for those corresponding to the above components (D1) and (D2)) It is.

  The component (D3) is not particularly limited as long as it acts as an acid diffusion control agent and does not correspond to the component (D1) and the component (D2). For example, the component includes an anion portion and a cation portion. Examples thereof include compounds and aliphatic amines.

Examples of the compound composed of an anion portion and a cation portion in the component (D3) include those in which the cation portion in the above components (d2-1) to (d2-3) is an ammonium cation. As the ammonium cation here, NH ₄ ⁺ , or a cation (first to quaternary ammonium cation) in which H bonded to the nitrogen atom is substituted with a hydrocarbon group which may have a hetero atom, or the nitrogen atom thereof. And a cyclic cation that forms a ring together.

Among the aliphatic amines, secondary aliphatic amines and tertiary aliphatic amines are preferable.
An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include an amine (alkyl amine or alkyl alcohol amine) or a cyclic amine in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms.
Specific examples of alkylamines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di- -Dialkylamines such as n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , Trialkylamines such as tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine; diethanolamine, triethanolamine, diisopropanolamine, Li isopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine. Among these, a trialkylamine having 5 to 10 carbon atoms is more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

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

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

As the component (D3), an aromatic amine may be used.
Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine and the like.

As the component (D3), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (D3), the component (D3) is usually used in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the component (A) in the resist composition. By setting the above range, it is possible to balance with other components, and various lithographic properties are improved.

≪ (E) component: at least one compound selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and derivatives thereof≫
The resist composition of the present embodiment is composed of an organic carboxylic acid and phosphorus oxo acid and its derivatives as optional components for the purpose of preventing sensitivity deterioration, improving the resist pattern shape, retention time stability, and the like. At least one compound (E) selected from the group (hereinafter referred to as “component (E)”) can be contained.
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids include phosphoric acid, phosphonic acid, and phosphinic acid. Among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include an ester obtained by substituting the hydrogen atom of the oxo acid with a hydrocarbon group, and examples of the hydrocarbon group include an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of phosphinic acid derivatives include phosphinic acid esters and phenylphosphinic acid.
In the resist composition of this embodiment, as the component (E), one type may be used alone, or two or more types may be used in combination.
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 with respect to 100 parts by mass of the component (A).

≪ (F) component: Fluorine additive component≫
The resist composition of the present embodiment may contain a fluorine additive component (hereinafter referred to as “(F) component”) in order to impart water repellency to the resist film or improve lithography properties.
Examples of the component (F) include those described in JP 2010-002870 A, JP 2010-032994 A, JP 2010-277043 A, JP 2011-13569 A, and JP 2011-128226 A. These fluorine-containing polymer compounds can be used.
More specifically, examples of the component (F) include a polymer having a structural unit (f1) represented by the following formula (f1-1). As this polymer, a polymer (homopolymer) consisting only of the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) and the structural unit (a1) It is preferably a copolymer of the structural unit (f1), a structural unit derived from acrylic acid or methacrylic acid, and the 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 ( Structural units derived from (meth) acrylates are preferred.

［式中、Ｒは前記と同様であり、Ｒｆ^１０２およびＲｆ^１０３はそれぞれ独立して水素原子、ハロゲン原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基を表し、Ｒｆ^１０２およびＲｆ^１０３は同じであっても異なっていてもよい。ｎｆ^１は１〜５の整数であり、Ｒｆ^１０１はフッ素原子を含む有機基である。］

[Wherein, R is the same as defined above, and 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, Rf ¹⁰² and Rf ¹⁰³ may be the same or different. nf ¹ is an integer of ¹ to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom. ]

In the formula (f1-1), R bonded to the α-position carbon atom is the same as described above. R is preferably a hydrogen atom or a methyl group.
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 of Rf ¹⁰² and Rf ¹⁰³ include the same as the alkyl group having 1 to 5 carbon atoms of R, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ include groups in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. It is done. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. The inter alia ^{Rf 102} and ^{Rf 103,} a hydrogen atom, a fluorine atom, or an alkyl group of 1 to 5 carbon atoms is preferable, a hydrogen atom, a fluorine atom, a methyl group or an ethyl group, preferred.
In formula (f1-1), nf ¹ is an integer of ¹ to 5, an integer of 1 to 3 is preferable, and 1 or 2 is more preferable.

In formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms. The carbon number of 1 to 10 is particularly preferable.
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 fluorinated, and 60% or more. Fluorination is particularly preferred because the hydrophobicity of the resist film during immersion exposure is increased.
Among ^these, as ^{Rf 101,} more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, trifluoromethyl _{group, -CH 2 -CF 3, -CH 2} -CF 2 -CF 3, -CH (CF 3 ) ₂ , —CH ₂ —CH ₂ —CF ₃ , —CH ₂ —CH ₂ —CF ₂ —CF ₂ —CF ₂ —CF ₃ are particularly preferred.

(F) As for the mass mean molecular weight (Mw) (polystyrene conversion reference | standard by a gel permeation chromatography), 1000-50000 are preferable, 5000-40000 are more preferable, and 10000-30000 are the most preferable. When it is below the upper limit of this range, it has sufficient solubility in a resist solvent for use as a resist, and when it is above the lower limit of this range, the water repellency of the resist film is good.
The dispersity (Mw / Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

In the resist composition of this embodiment, as the component (F), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (F), the content of the component (F) is usually used at a ratio of 0.5 to 10 parts by mass with respect to 100 parts by mass of the component (A).

≪ (S) component: organic solvent component≫
The resist composition of this embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as “(S) component”).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution, and any conventionally known solvent for chemically amplified resist compositions can be appropriately selected. It can be selected and used.
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, 2-heptanone; ethylene glycol, diethylene glycol, propylene glycol , Polyhydric alcohols such as dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, the polyhydric alcohols or the ester bond Monoalkyl ether or monophenyl ether such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether Derivatives of polyhydric alcohols such as compounds having an ether bond such as tellurium [in these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane And esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl Methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesithi Examples thereof include aromatic organic solvents such as len and dimethyl sulfoxide (DMSO).
In the resist composition of this embodiment, the component (S) may be used alone or as a mixed solvent of two or more.
Of these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA: EL or cyclohexanone is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. . Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferable.
In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, as a mixing ratio, the mass ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of the component (S) used is not particularly limited, and is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. 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.

  The resist composition according to the present embodiment further includes, if desired, miscible additives such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, and an antihalation agent. A dye or the like can be added and contained as appropriate.

The resist composition of this embodiment contains the above-described component (A), the component (BD1), and the optional component as necessary.
For example, when the component (BD1) is used as the component (B1), a resist composition containing the component (A), the component (B1), and the component (D2) or the component (D3) is preferable. For example, when the component (BD1) is used as the component (D1), a resist composition containing the component (A), the component (B2), and the component (D1) is preferable.
Furthermore, for example, when the component (BD1) is used as the component (B1) and the component (D1), respectively, a resist composition containing the component (A), the component (B1), and the component (D1) is preferable. Can be mentioned.

  The resist composition of the present embodiment described above contains the compound (BD1) represented by the general formula (bd1). About this (BD1) component, since the anion part has the specific structure (bulky structure) which consists mainly of hydrocarbons, the hydrophobicity is comparatively improved. Thereby, the compatibility between the compound (BD1) and the substrate component (A) is increased, and the acid diffusibility in the resist film is appropriately controlled. In addition, the reactivity of the (BD1) component is enhanced because the cation moiety has an electron withdrawing group. By including such a component (BD1) composed of an anion portion and a cation portion, it is presumed that according to the resist composition of the embodiment, lithography properties (roughness reduction, etc.) are further improved and higher sensitivity can be achieved. The

  Further, when the resist composition of the embodiment is used, the uniformity of the compound (BD1) is increased in the formed resist film, so that a resist pattern having a good shape with high resolution and reduced roughness can be easily formed.

(Resist pattern formation method)
The resist pattern forming method according to the second aspect of the present invention includes a step of forming a resist film on a support using the resist composition of the above-described embodiment, a step of exposing the resist film, and the post-exposure step The resist film is developed to form a resist pattern.
As one embodiment of such a resist pattern forming method, for example, there is a resist pattern forming method performed as follows.

First, the resist composition of the above-described embodiment is applied on a support with a spinner or the like, and a baking (post-apply bake (PAB)) treatment is preferably performed at a temperature of 80 to 150 ° C. for 40 to 120 seconds, for example. Is applied for 60 to 90 seconds to form a resist film.
Next, the resist film is exposed through a mask (mask pattern) on which a predetermined pattern is formed using an exposure apparatus such as an electron beam lithography apparatus or an EUV exposure apparatus, or an electron beam not through the mask pattern. After performing selective exposure such as drawing by direct irradiation, baking (post-exposure baking (PEB)) treatment is performed, for example, at a temperature of 80 to 150 ° C. for 40 to 120 seconds, preferably 60 to 90 seconds.
Next, the resist film is developed. The development treatment is performed using an alkaline developer in the case of an alkali development process, and using a developer (organic developer) containing an organic solvent in the case of a solvent development process.
A rinsing treatment is preferably performed after the development treatment. The rinse treatment is preferably a water rinse using pure water in the case of an alkali development process, and is preferably a rinse solution containing an organic solvent in the case of a solvent development process.
In the case of a solvent development process, after the development process or the rinse process, a process of removing the developer or rinse liquid adhering to the pattern with a supercritical fluid may be performed.
Drying is performed after development or rinsing. In some cases, a baking process (post-bake) may be performed after the development process.
In this way, a resist pattern can be formed.

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

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

Examples of the alkali developer used for the development treatment in the alkali development process include a 0.1 to 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.
The organic solvent contained in the organic developer used for the development process in the solvent development process is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure). It can be selected as appropriate. Specific examples include ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, ether solvents, and other polar solvents, hydrocarbon solvents, and the like.
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 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. A nitrile solvent is an organic solvent containing a nitrile group in its 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 organic solvents, there are organic solvents that contain multiple types of functional groups that characterize each of the above solvents in the structure, but in that case, any of the solvent types that contain the functional groups of the organic solvent is applicable. Shall. For example, diethylene glycol monomethyl ether corresponds to both alcohol solvents and ether solvents in the above classification.
The hydrocarbon solvent is a hydrocarbon solvent made of a hydrocarbon which may be halogenated and having no 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.
Among the above, the organic solvent contained in the organic developer is preferably a polar solvent, and is preferably a ketone solvent, an ester solvent, a nitrile solvent, or the like.

  Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, and methyl ethyl ketone. , Methyl isobutyl ketone, acetylacetone, acetonyl acetone, ionone, diacetyl alcohol, acetyl carbinol, acetophenone, methyl naphthyl ketone, 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, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono Propyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene Recall 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-methoxy Nethyl 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, pyruvin Methyl acetate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, 2-hydroxypropionate Examples include ethyl acid, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, and propyl-3-methoxypropionate. Among these, butyl acetate is preferable as the ester solvent.

  Examples of the nitrile solvent include acetonitrile, propionitryl, valeronitrile, butyronitryl and the like.

A known additive can be blended in the organic developer as required. Examples of the additive include a surfactant. The surfactant is not particularly limited. For example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used. As the surfactant, a nonionic surfactant is preferable, and a nonionic fluorine-based surfactant or a nonionic silicon-based surfactant is more preferable.
When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and preferably 0.01 to 0.00% with respect to the total amount of the organic developer. 5 mass% is more preferable.

  The development process can be performed by a known development method. For example, a method in which a support is immersed in a developer for a certain period of time (dip method), a developer is raised on the surface of the support by surface tension, and is left for a certain period of time (Paddle method), spraying developer on the surface of the support (spray method), coating the developer while scanning the developer coating nozzle at a constant speed on the support rotating at a constant speed The method of continuing (dynamic dispensing method) etc. are mentioned.

As the organic solvent contained in the rinsing liquid used for the rinsing process after the development process in the solvent developing process, for example, an organic solvent that is difficult to dissolve the resist pattern is selected as appropriate from the organic solvents used as the organic solvent used in the organic developer. Can be used. Usually, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is used. Among these, at least one selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents and amide solvents is preferable, and at least one selected from alcohol solvents and ester solvents is preferable. More preferred are alcohol solvents.
The alcohol solvent used for the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be linear, branched or cyclic. Specific examples include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. It is done. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferable, and 1-hexanol and 2-hexanol are more preferable.
Any one of these organic solvents may be used alone, or two or more thereof may be used in combination. Moreover, you may mix and use the organic solvent and water other than the above. However, in consideration of development characteristics, the amount of water in the rinsing liquid is preferably 30% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, more preferably 3% by mass with respect to the total amount of the rinsing liquid. The following are particularly preferred:
A well-known additive can be mix | blended with a rinse liquid as needed. Examples of the additive include a surfactant. Examples of the surfactant are the same as described above, and a nonionic surfactant is preferable, and a nonionic fluorine-based surfactant or a nonionic silicon-based surfactant is more preferable.
When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0.5% by mass with respect to the total amount of the rinse liquid. % Is more preferable.

  The rinse treatment (washing treatment) using the rinse liquid can be performed by a known rinse method. Examples of the rinsing method include a method of continuously applying a rinsing liquid onto a support rotating at a constant speed (rotary coating method), a method of immersing the support in a rinsing liquid for a predetermined time (dip method), The method (spray method) etc. which spray the rinse liquid on the support body surface are mentioned.

  In the resist pattern forming method of the present embodiment described above, the resist composition according to the first aspect described above is used. Therefore, when forming a resist pattern, a higher sensitivity and better lithography characteristics (roughness) Reduction) and the like can be formed.

(Compound)
The compound which concerns on the 3rd aspect of this invention consists of an anion part and a cation part represented by the following general formula (bd1).

［式中、Ｒｘ^１〜Ｒｘ^４は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。Ｒｙ^１〜Ｒｙ^２は、それぞれ独立に、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は相互に結合して環構造を形成していてもよい。

は二重結合又は単結合である。Ｒｚ^１〜Ｒｚ^４は、それぞれ独立に、原子価が許容する場合、置換基を有してもよい炭化水素基もしくは水素原子を表すか、又は２個以上が相互に結合して環構造を形成していてもよい。但し、Ｒｘ^１〜Ｒｘ^４、Ｒｙ^１〜Ｒｙ^２及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個はアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。ｍは１以上の整数であって、Ｍ^ｍ＋は、電子求引性基を有するｍ価の有機カチオンを表す。］

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ]

  The compound represented by the general formula (bd1) is the same compound as the component (BD1) in the description of the resist composition of the above-described embodiment.

[Production Method of Compound (BD1)]
(BD1) A component can be manufactured using a well-known method.
As a method for producing the (BD1) component, for example, as in the following reaction formula, an alkene or alkyne ((starting raw material 2) in the following reaction formula) is converted to a conjugated diene ((starting raw material 1) in the following reaction formula) Examples thereof include a method using a Diels-Alder reaction that adds to form a ring structure ((intermediate) in the following reaction formula). Specifically, a desired anion group is introduced into a product (intermediate) by Diels-Alder reaction to obtain a precursor, and then a desired cation is introduced by a salt exchange reaction (BD1). Ingredients are obtained. Alternatively, a Diels-Alder reaction is performed using an alkene, alkyne, or conjugated diene containing a substituent derived from a desired anion group (a substituent capable of introducing a desired anion group), and an intermediate is obtained. The precursor (BD1) component may be obtained by introducing a precursor of the anion group and introducing a desired cation by a salt exchange reaction.
The conjugated diene is appropriately selected according to the target compound (component (BD1)), and for example, anthracene or a derivative thereof, triptycene or a derivative thereof may be used.
The method of introducing an anion group is, for example, a method using an esterification reaction; an ammonium salt having an anion group into which a tosyl group is introduced, and a lithium compound having a ring structure of an anion skeleton (from Diels-Alder reaction) Examples thereof include a method using a reaction, a method of obtaining a sulfonate by oxidizing a halogen atom-containing intermediate to obtain a sulfinate by oxidizing the intermediate.

When an esterification reaction is used as a method for introducing an anion group, for example, a compound represented by the above general formula (bd1) [a compound having an anion group represented by the general formula (bd1-r-an1), Y ^b01 = Examples of a method for producing —C (═O) —O—] include a production method according to an embodiment including the following first and second steps.
An anion group represented by the general formula (bd1-r-an1) and Y ^b01 = —C (═O) —O— is represented by “the general formula (b1-r-an10)”. Anion group ”. Let the compound of interest manufactured with the manufacturing method of embodiment containing this 1st-2nd process be a compound (B1-0).
The raw material used in each step may be a commercially available material or a synthesized material.
The organic solvent used in the first and second steps is not particularly limited as long as the compound used in each step can be dissolved and does not react with these compounds. For example, dichloromethane, dichloroethane, chloroform, tetrahydrofuran, N, N -Dimethylformamide, dimethylacetamide, dimethyl sulfoxide, acetonitrile, propionitrile and the like.

-1st process In a 1st process, an intermediate body and compound (I) are melt | dissolved in an organic solvent (dichloromethane etc.), and it reacts in presence of a base. Then, a precursor (Bpre) is obtained by performing filtration, concentration, and the like.

［式中、Ｒ^ｂ０１及びＶ^ｂ０１は、上記式（ｂｄ１−ｒ−ａｎ１）中のＲ^ｂ０１及びＶ^ｂ０１とそれぞれ同様である。（Ｍ_１”^ｍ＋）_１／ｍは、アンモニウムカチオンである。Ｒｘ^５、Ｒｘ^６、Ｒｚ^１〜Ｒｚ^４、Ｒ^０２１、ｎ１、ｎ１１、Ｒ^０２２、ｎ２及びｎ２１は、上記式（ｂｄ１−ａｎ３）中のＲｘ^５、Ｒｘ^６、Ｒｚ^１〜Ｒｚ^４、Ｒ^０２１、ｎ１、ｎ１１、Ｒ^０２２、ｎ２及びｎ２１とそれぞれ同様である。但し、Ｒｘ^５〜Ｒｘ^６及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個は一般式（ｂ１−ｒ−ａｎ１０）で表されるアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。］

^{Wherein, R b01} and ^{V b01} are each similar to the above formula (bd1-r-an1) in ^{R b01} and ^{V b01.} (M ₁ ″ ^{m +} ) _{1 / m} is an ammonium cation. Rx ⁵ , Rx ⁶ , Rz ^{1 to} Rz ⁴ , R ⁰²¹ , n1, n11, R ⁰²² , n2 and n21 are represented by the above formula (bd1-an3) Rx ⁵ , Rx ⁶ , Rz ^{1 to} Rz ⁴ , R ⁰²¹ , n1, n11, R ⁰²² , n2 and n21 are the same as each other, provided that at least one of Rx ^{5 to} Rx ⁶ and Rz ^{1 to} Rz ⁴ Each has an anion group represented by the general formula (b1-r-an10), and the whole anion part becomes an n-valent anion, where n is an integer of 1 or more.]

Examples of the base added in the first step include organic bases such as triethylamine, 4-dimethylaminopyridine, pyridine, ethyldiisopropylaminocarbodiimide (EDCI) hydrochloride, dicyclohexylcarboimide (DCC), diisopropylcarbodiimide, and carbodiimidazole; Examples thereof include inorganic bases such as sodium hydride, K ₂ CO ₃ , and Cs ₂ CO ₃ .
The cation part of compound (I) may be an ammonium cation derived from an aliphatic amine or an ammonium cation derived from an aromatic amine.

About 1-3 equivalent is preferable with respect to an intermediate body, and, as for the usage-amount of compound (I), 1-2 equivalent is more preferable.
0-50 degreeC is preferable and, as for reaction temperature, 5-40 degreeC is more preferable.

-Second Step In the second step, the precursor (Bpre) and the compound (II) for salt exchange are reacted in a solvent such as water, dichloromethane, acetonitrile, chloroform, etc., and the precursor (Bpre) and the compound ( The target compound (B1-0) is obtained by salt exchange with the organic cation in II).

［式中、Ｒ^ｂ０１及びＶ^ｂ０１は、上記式（ｂ１−ｒ−ａｎ１０）中のＲ^ｂ０１及びＶ^ｂ０１とそれぞれ同様である。（Ｍ_１”^ｍ＋）_１／ｍは、アンモニウムカチオンである。Ｒｘ^５、Ｒｘ^６、Ｒｚ^１〜Ｒｚ^４、Ｒ^０２１、ｎ１、ｎ１１、Ｒ^０２２、ｎ２及びｎ２１は、上記式（ｂｄ１−ａｎ３）中のＲｘ^５、Ｒｘ^６、Ｒｚ^１〜Ｒｚ^４、Ｒ^０２１、ｎ１、ｎ１１、Ｒ^０２２、ｎ２及びｎ２１とそれぞれ同様である。但し、Ｒｘ^５〜Ｒｘ^６及びＲｚ^１〜Ｒｚ^４のうち少なくとも１個は一般式（ｂ１−ｒ−ａｎ１０）で表されるアニオン基を有し、アニオン部全体でｎ価のアニオンとなる。ｎは１以上の整数である。Ｚ⁻は、非求核性イオンである。（Ｍ^ｍ＋）_１／ｍは、ｍ価の有機カチオンであり、上記と同様である。］

^{Wherein, R b01} and ^{V b01} are each similar to the above formula (b1-r-an10) in ^{R b01} and ^{V b01.} (M ₁ ″ ^{m +} ) _{1 / m} is an ammonium cation. Rx ⁵ , Rx ⁶ , Rz ^{1 to} Rz ⁴ , R ⁰²¹ , n1, n11, R ⁰²² , n2 and n21 are represented by the above formula (bd1-an3) Rx ⁵ , Rx ⁶ , Rz ^{1 to} Rz ⁴ , R ⁰²¹ , n1, n11, R ⁰²² , n2 and n21 are the same as each other, provided that at least one of Rx ^{5 to} Rx ⁶ and Rz ^{1 to} Rz ⁴ Each has an anion group represented by the general formula (b1-r-an10) and becomes an n-valent anion in the whole anion part, where n is an integer of 1 or more, Z ⁻ is a non-nucleophilic ion. (M ^{m +} ) _{1 / m} is an m-valent organic cation, which is the same as described above.]

Examples of Z ⁻ include halogen ions such as bromine ion and chlorine ion; ions that can be acid having lower acidity than the precursor (Bpre), BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ^−, or ClO. _4- ^{and the} like.
The reaction temperature is preferably about 0 to 100 ° C, more preferably about 0 to 50 ° C.
The reaction time varies depending on the reactivity between the precursor (Bpre) and the salt exchange compound (II), the reaction temperature, etc., but is usually preferably 10 minutes to 24 hours, more preferably 10 minutes to 12 hours. preferable.

After completion of the salt exchange reaction, the compound in the reaction solution may be isolated and purified. For isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography and the like can be used in appropriate combination.
The structure of the compound obtained as described above includes ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method, mass spectrometry (MS ) Method, elemental analysis method, X-ray crystal diffraction method and other general organic analysis methods.

The intermediate is appropriately selected according to the target compound (B1-0), and examples thereof include a product by Diels-Alder reaction represented by the following reaction formula. For (starting material 1) in the following reaction formula, anthracene or a derivative thereof can be used. A compound having an ethylenic double bond such as an acrylate can be used as (starting material 2) in the following reaction formula.
Examples of the intermediate include triptycene or a derivative thereof.

［式中、Ｒｘ_１’〜Ｒｘ _４’は、前記Ｒｘ^１〜Ｒｘ^４と同様である。Ｒｙ_１’〜Ｒｙ_２’は、前記Ｒｙ^１〜Ｒｙ^２と同様である。

は三重結合又は二重結合である。

は二重結合又は単結合である。Ｒｚ_１’〜Ｒｚ_４’は、前記Ｒｚ^１〜Ｒｚ^４と同様である。但し、Ｒｘ_１’〜Ｒｘ_４’、Ｒｙ_１’〜Ｒｙ_２’及びＲｚ_１’〜Ｒｚ_４’のうち少なくとも１個は、前記アニオン基を導入し得る、脱離基を含む基である。］

[Wherein, Rx ₁ ′ to Rx ₄ ′ are the same as Rx ^{1 to} Rx ⁴ above. Ry ₁ ′ to Ry ₂ ′ are the same as Ry ^{1 to} Ry ² .

Is a triple bond or a double bond.

Is a double bond or a single bond. Rz ₁ ′ to Rz ₄ ′ are the same as Rz ^{1 to} Rz ⁴ . However, at least one of Rx ₁ ′ to Rx ₄ ′, Ry ₁ ′ to Ry ₂ ′, and Rz ₁ ′ to Rz ₄ ′ is a group including a leaving group that can introduce the anionic group. ]

  Examples of the group containing a leaving group into which an anion group can be introduced include a halogen atom, a group containing a halogen atom, and a group having a substituent capable of dehydration condensation (hydroxyl group, carboxy group, etc.).

  When an esterification reaction is used as a method for introducing an anionic group, examples of the group containing the leaving group include a substituent capable of dehydration condensation. For example, the intermediate in the reaction formula shown in the first step preferably has a substituent capable of dehydration condensation (such as a hydroxyl group or a carboxy group). In this first step, an esterification reaction is carried out to obtain an ammonium sulfonate salt as a precursor (Bpre).

  In the case of using a reaction between an ammonium salt having an anion group into which a tosyl group is introduced and a lithium compound having a ring structure of an anion skeleton (derived from Diels-Alder reaction) as a method for introducing an anion group, the above leaving group Examples of the group containing include a halogen atom or a group containing a halogen atom, preferably a bromine atom. An intermediate containing a halogen atom (preferably a bromine atom) is converted to Li to form a Li compound, and then reacted with an ammonium salt having an anion group into which a tosyl group is introduced to obtain an ammonium sulfonate salt as a precursor.

  As a method for introducing an anionic group, when a method in which an intermediate containing a halogen atom is sulfinated to obtain a sulfinate and then oxidized to obtain a sulfonate, the above group containing a leaving group is used. , A halogen atom, or a group containing a halogen atom, preferably a bromine atom. An intermediate containing a halogen atom (preferably a bromine atom) is converted to an ammonium sulfinate by using a sulfinating agent in the presence of an amine, and further reacted with an oxidizing agent to change an ammonium sulfonate salt as a precursor. obtain.

  The target compound ((BD1) component) can be obtained by carrying out the salt exchange in the above-mentioned second step on each precursor ammonium sulfonate.

(Acid generator)
The acid generator according to the fourth aspect of the present invention is composed of the compound according to the third aspect described above.
Such an acid generator is useful as an acid generator component for a chemically amplified resist composition. By using such an acid generator component in a chemically amplified resist composition, lithography characteristics such as roughness reduction can be improved in resist pattern formation, the pattern shape can be kept good, and high sensitivity can be achieved. By using such an acid generator component, particularly high sensitivity to an EB or EUV light source can be easily obtained. In addition, according to the chemically amplified resist composition containing such an acid generator component, the resolution performance is further improved.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
In this example, the compound represented by the chemical formula (1) is represented as “compound (1)”, and the compounds represented by other chemical formulas are represented in the same manner.

<Production of compound>
(Production Example 1)
In a 300 mL pressure-resistant reaction vessel, 4-bromo-3,3,4,4-tetrafluoro-1-butene (8.7 g, 42 mmol), anthracene (5.0 g, 28 mmol), and toluene (100 g) were added. The reaction was carried out at 150 ° C. for 24 hours. Next, after cooling to room temperature, it concentrated using the rotary evaporator. Methanol (50 g) was added to this concentrate and stirred, and the precipitated solid was filtered. Then, the intermediate body 1 was obtained by making it dry under reduced pressure (6.0g, a yield = 55.6%).

In a 200 mL three-necked flask, Intermediate 1 (5.8 g, 15 mmol), benzyltrimethylammonium chloride (2.9 g, 16 mmol), sodium dithionite (6.7, 38 mmol), and sodium bicarbonate (3.8 g). , 45 mmol), acetonitrile (16 g), and H ₂ O (16 g) were added and reacted at 65 ° C. for 4 hours with stirring. Next, after cooling to room temperature, the reaction solution was filtered, H ₂ O (16 g) and dichloromethane (25 g) were added to the filtrate, and the mixture was stirred for 30 minutes, and then the aqueous layer was removed. Next, it was washed twice with ultrapure water (160 g), and the organic layer was concentrated using a rotary evaporator. Acetonitrile (77 g) was added to the concentrate for dissolution, 30% aqueous hydrogen peroxide (2.7 g, 24 mmol) was added, and the mixture was reacted at 45 ° C. for 7 hours. After cooling to room temperature, dichloromethane (78 g) and saturated aqueous sodium sulfite solution (78 g) were added, and the mixture was stirred with ultrapure water for 30 minutes, and then the aqueous layer was removed. After washing twice with ultrapure water (78 g), methyl tert-butyl ether (MTBE) (156 g) was added and stirred for 30 minutes. The precipitate was filtered and dried under reduced pressure to obtain a precursor (Bpre-1) (5.8 g, yield = 66.8%).

(Production Example 2)
Anthracene (5.0 g, 28 mmol), methyl acrylate (3.6 g, 42 mmol), aluminum chloride (0.37 g, 2.8 mmol), and toluene (50 g) were added to a 100 mL three-necked flask and stirred. The reaction was carried out at 80 ° C. for 4 hours. After cooling, ultrapure water (50 g) and MTBE (74 g) were added, and after stirring for 30 minutes, the aqueous layer was removed. The organic layer was washed 3 times with ultrapure water (50 g), and the organic layer was concentrated using a rotary evaporator. The concentrate was recrystallized from 2-isopropanol to obtain Intermediate 2 (5.9 g, yield = 79.6%).

  Sodium hydroxide (3.8 g, 95 mmol) and ultrapure water (38 g) were added to a 100 mL three-necked flask, and after stirring and dissolving, Intermediate 2 (5.0 g, 19 mmol) was dispersed, Reacted for hours. After cooling to room temperature, the solution was neutralized by adding hydrochloric acid until neutral, and then MTBE (50 g) was added and stirred for 30 minutes, and then the aqueous layer was removed. The organic layer was washed three times with ultrapure water (50 g), and the organic layer was concentrated using a rotary evaporator to obtain Intermediate 3 (4.6 g, yield = 97.2%).

Intermediate 3 (4.0 g, 16 mmol), compound (I-1) (6.0 g, 16 mmol), and dichloromethane (87 g) were added to a 100 mL three-necked flask and dissolved by stirring at room temperature. .
Next, diisopropylcarbodiimide (2.2 g, 18 mmol) and dimethylaminopyridine (0.098 g, 0.8 mmol) were added and reacted at room temperature for 5 hours. The reaction solution was filtered, and the filtrate was concentrated using a rotary evaporator. The concentrate was dissolved in acetonitrile (17 g) and then added dropwise to MTBE (170 g), and the precipitated solid was filtered. The filtrate was dissolved again with acetonitrile (17 g), added dropwise to MTBE (170 g), and the precipitated solid was filtered. After repeating this operation twice, the residue was dried under reduced pressure to obtain a precursor (Bpre-2) (7.6 g, yield = 78.2%).

(Production Example 3)
Intermediate 4 was obtained in the same manner as in Production Example of Intermediate 2 except that methyl acrylate (3.6 g, 42 mmol) was changed to maleic anhydride (4.0 g, 42 mmol) (6.4 g, Yield = 82.3%).

  Into a 100 mL three-necked flask was charged Intermediate 4 (6.0 g, 22 mmol), 5-hydroxynorbornane 2,6-lactone (4.0 g, 26 mmol), and dichloromethane (120 g), and the mixture was stirred at room temperature. Dissolved. Next, dimethylaminopyridine (0.13 g, 1 mmol) and triethylamine (5.5 g, 54 mmol) were added and reacted at room temperature for 24 hours. Ultrapure water (120 g) was added and stirred, and then neutralized by adding hydrochloric acid until the aqueous layer became acidic. After further stirring for 30 minutes, the aqueous layer was removed. The organic layer was washed 3 times with ultrapure water (120 g), and the organic layer was concentrated using a rotary evaporator to obtain Intermediate 5 (7.2 g, yield = 77.1%).

  A precursor (Bpre-3) was prepared in the same manner as in the preparation of the precursor (Bpre-2) except that the intermediate 3 (4.0 g, 16 mmol) was changed to the intermediate 5 (6.8 g, 16 mmol). (6.6 g, yield = 53.1%) was obtained.

(Production Example 4)
The precursor (Bpre-2) was prepared in the same manner as in the preparation example of the precursor (Bpre-2) except that the compound (I-1) (6.0 g, 16 mmol) was changed to the compound (I-2) (5.7 g, 16 mmol). Body (Bpre-4) was obtained (6.2 g, yield = 65.4%).

(Production Example 5)
Intermediate 3 (4.8 g, 19 mmol) and tetrahydrofuran (THF) (50 g) were added to a 100 mL three-necked flask and dissolved by stirring at room temperature. Next, LiAlH ₄ (0.86 g, 23 mmol) was added and reacted at room temperature for 3 hours. Next, ultrapure water (50 g) and MTBE (50 g) were added, and after stirring for 30 minutes, the aqueous layer was removed. Thereafter, the organic layer was washed three times with ultrapure water (50 g), and the organic layer was concentrated using a rotary evaporator to obtain Intermediate 6 (4.1 g, yield = 91.0%).

  In a 100 mL three-necked flask, intermediate 6 (4.0 g, 19 mmol), compound (I-3) (3.6 g, 18 mmol), and p-toluenesulfonic acid monohydrate (0.18 g, 0.9 mmol) And toluene (40 g) were added and refluxed at 110 ° C. for 24 hours. After cooling, the mixture was filtered, acetonitrile (160 g) was added to the residue, and the mixture was stirred at room temperature for 30 minutes and filtered. The filtrate was concentrated and methyl ethyl ketone (78 g) was added to the residue and stirred. Thereafter, the mixture was filtered and the filtrate was dried to obtain a precursor (Bpre-5) (4.9 g, yield = 62.4%).

(Production Example 6)
Compound (I-4) (10.0 g, 32 mmol), paratoluenesulfonyl chloride (6.7 g, 35 mmol), and dichloromethane (100 g) are added to a 100 mL three-necked flask, and the mixture is stirred and dispersed at room temperature. It was. Next, pyridine (3.0 g, 39 mmol) was added over 30 minutes and reacted at room temperature for 6 hours. The reaction solution was washed 4 times with ultrapure water (100 g), MTBE (150 g) was added to the organic layer, and the mixture was stirred for 30 minutes. The precipitate was filtered and dried under reduced pressure to obtain Intermediate 7 (5.8 g, yield = 66.8%).

  9-Bromotriptycene (10.0 g, 30 mmol) and THF (100 g) were added to a 200 mL three-necked flask and dissolved by stirring. After cooling to −78 ° C., 1.6M n-butyllithium hexane solution (20.6 ml, 33 mmol) was added, and the mixture was stirred at −78 ° C. for 1 hour. Next, what melt | dissolved the intermediate body 7 (12.6g, 27mmol) in THF (126g) was thrown in, and it was made to react at -50 degreeC for 3 hours. The reaction solution was poured into ultrapure water (250 g) over 1 hour, and then dichloromethane (160 g) was added and stirred for 30 minutes, and then the aqueous layer was removed. The organic layer was washed 3 times with ultrapure water (150 g), and then the organic layer was added dropwise to MTBE (160 g), and the precipitated solid was filtered. This filtrate was dissolved in acetonitrile (70 g), added dropwise to MTBE (140 g), and the precipitated solid was filtered. After this operation was repeated twice, the filtrate was dried under reduced pressure to obtain a precursor (Bpre-6) (6.0 g, yield = 36.7%).

(Production Example 7)
Intermediate 3 (4.0 g, 16 mmol), compound (I-5) (5.0 g, 16 mmol), and dichloromethane (87 g) were charged into a 100 mL three-necked flask and dissolved by stirring at room temperature. . Next, diisopropylcarbodiimide (2.2 g, 18 mmol) and dimethylaminopyridine (0.098 g, 0.8 mmol) were added and reacted at room temperature for 5 hours. The reaction solution was filtered, and the filtrate was concentrated using a rotary evaporator. The concentrate was dissolved in acetonitrile (17 g) and then added dropwise to MTBE (170 g), and the precipitated solid was filtered. The filtrate was dissolved again with acetonitrile (17 g), added dropwise to MTBE (170 g), and the precipitated solid was filtered. After this operation was repeated twice, the filtrate was dried under reduced pressure to obtain a precursor (Bpre-7) (5.8 g, yield = 66.8%).

(Production Example 8)
Sodium hydroxide (3.6 g, 90 mmol) and ultrapure water (36 g) were added to a 100 mL three-necked flask, and after stirring and dissolving, intermediate 4 (5.0 g, 18 mmol) was dispersed, Reacted for hours. After cooling to room temperature, 20% hydrochloric acid (13.2 g, 72.4 mmol) and benzyltrimethylammonium chloride (5.0 g, 27 mmol) were added, and then MTBE (50 g) was added and stirred for 30 minutes, and then the aqueous layer was removed. did. The organic layer was washed three times with ultrapure water (50 g), and the organic layer was concentrated using a rotary evaporator to obtain a precursor (Bpre-8) (5.7 g, yield = 71.0%). ).

(Production Example of Compound (B1-3))
The precursor (Bpre-1) (5.0 g, 9.3 mmol) and the salt exchange compound C (3.5 g, 9.3 mmol) were dissolved in dichloromethane (50 g), ultrapure water (50 g) was added, The reaction was allowed to proceed for 30 minutes at room temperature. After completion of the reaction, the aqueous phase was removed, and the organic phase was washed 4 times with ultrapure water (50 g). The organic phase was concentrated to dryness using a rotary evaporator to obtain compound (B1-3) (6.0 g, yield = 88.9%).

(Examples of other compound production)
Except having changed the combination of said precursor (Bpre-1)-precursor (Bpre-8) and the following compound A for salt exchange-compound P for salt exchange, said "compound (B1-3 In the same manner as in “Production example of”), the following compounds (B1-1) to (B1-12), (B2-1), (B2-4) to (B2-7), ( D2-4) and compound (D1-1) were obtained.

  Each of the obtained compounds was subjected to NMR measurement, and the structure was identified from the following analysis results.

Compound (B1-1): Combination of precursor (Bpre-1) and salt exchange compound A
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.44 (s, Ph, 1H), 8.26 (d, Ph, 1H), 7.78-8.03 (m, Ph, 12H), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.40 (s, CH, 1H), 3.15-3.22 (m, CF2CH, 1H), 1.95-2.15 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) =-62.9, -111.3, -117.4

Compound (B1-2): Combination of precursor (Bpre-1) and salt exchange compound B
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.60-8.80 (m, ArH, 5H), 8.41 (d, ArH, 2H), 8.28 (d, ArH, 2H), 8.06 (t, ArH, 2H), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.40 (s, CH, 1H), 3.32 (s, CH3, 6H), 3.15-3.22 (m, CF2CH, 1H ), 1.95-2.15 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) =-61.2, -111.3, -117.4

Compound (B1-3): Combination of precursor (Bpre-1) and compound C for salt exchange
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.77-7.98 (m, ArH, 11H), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.40 (s, CH, 1H), 3.15-3.22 (m, CF2CH, 1H), 1.95-2.15 (m, CH2,2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 103.9, −111.3, −117.4

Compound (B1-4): Combination of precursor (Bpre-2) and salt exchange compound D
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.49 (dd, ArH, 4H), 7.99 (t, ArH, 2H), 7.66-7.87 (m, ArH, 3H), 7.42-7.58 (m, ArH, 2H), 7.01-7.47 (m, ArH, 8H), 4.72 (s, CH, 1H), 4.43 (s, CH, 1H), 4.23, (t, CH2, 2H), 2.95-3.02 (m, CH, 1H), 2.63-2.73, (m, CF2CH2, 2H), 1.86-2.07 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 104.1, −111.3, −117.4

Compound (B1-5): Combination of precursor (Bpre-3) and salt exchange compound D
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.49 (dd, ArH, 4H), 7.99 (t, ArH, 2H), 7.66-7.87 (m, ArH, 3H), 7.42-7.58 (m, ArH, 2H), 7.01-7.47 (m, ArH, 8H), 4.70 (d, OCH (lactone), 1H), 4.58 (t, COOCH (lactone), 1H), 4.50 (d, CH, 2H), 4.22 , (t, COOCH2, 2H), 3.32 (m, CH (lactone), 1H), 3.20 (t, COCH, 2H), 2.63-2.73, (m, CF2CH2, CH (lactone) 4H), 1.60-2.20 ( m, CH2 (lactone), 4H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 104.1, −111.3, −117.4

Compound (B1-6): Combination of precursor (Bpre-4) and salt exchange compound E
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.60 (s, ArH, 1H), 8.55 (d, ArH, 2H), 8.41 (d, ArH, 2H), 8.08 (d, ArH, 1H) 7.98 (t, ArH, 2H), 7.78 (t, ArH, 2H), 7.70 (t, ArH, 1H), 7.34 (d, ArH, 1H), 7.01-7.47 (m, ArH, 8H), 5.08 ( m, CFCH, 1H), 4.71 (s, CH, 1H), 4.42 (s, CH, 1H), 4.23 (m, CH2, 2H), 2.90 (m, CH, 1H), 2.45 (m, CFCH, 1H ), 1.82-2.07 (m, CH2, CFCH, 3H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) =-61.4, -112.5, -121.2

Compound (B1-7): Combination of precursor (Bpre-5) and salt exchange compound F
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.02-8.05 (m, ArH, 2H), 7.61-7.73 (m, ArH, 3H), 7.01-7.45 (m, ArH, 8H), 4.71 ( s, CH, 1H), 4.44 (S, CH, 1H), 4.31 (s, CH2, 2H), 3.86-3.96 (m, SCH2, 4H), 3.75 (t, OCH2, 4H), 2.93-3.00 (m , CH, 1H), 1.87-2.07 (m, CH2, 1H), 0.98-1.03 (m, CH, 1H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 107.9

Compound (B1-8): Combination of precursor (Bpre-5) and salt exchange compound G
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.15 (d, ArH, 2H), 7.84 (d, ArH, 2H), 7.01-7.45 (m, ArH, 8H), 4.71 (s, CH, 1H), 4.44 (s, CH, 1H), 4.31 (s, CH2, 2H), 3.86-3.96 (m, SCH2, 4H), 3.75 (t, OCH2, 4H), 2.93-3.00 (m, CH, 1H ), 1.87-2.07 (m, CH2, 1H), 0.98-1.03 (m, CH, 1H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 104.0, −107.9

Compound (B1-9): Combination of precursor (Bpre-7) and salt exchange compound H
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.58 (d, ArH, 2H), 8.17 (d, ArH, 2H), 7.95-8.11 (m, ArH, 6H), 7.76 (t, ArH, 1H), 7.65 (t, ArH, 2H), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.31-4.58 (m, CH, CF2CH2, 3H), 2.95-3.02 (m , CH, 1H), 1.85-2.05 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 111.4

Compound (B1-10): Combination of precursor (Bpre-6) and compound I for salt exchange
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.98-8.07 (m, ArH, 6H), 7.94 (t, ArH, 1H), 7.83 (t, ArH, 2H), 7.68-7.82 (m, ArH, 6H), 6.60-6.80 (m, ArH, 6H), 5.54 (s, CH, 1H), 2.42-2.47 (t, CF2CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 102.3, −105.6

Compound (B1-11): Combination of precursor (Bpre-6) and salt exchange compound J
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.29 (d, ArH, 4H), 7.93-8.09 (m, ArH, 6H), 7.68-7.82 (m, ArH, 6H), 6.60-6.80 ( m, ArH, 6H), 5.54 (s, CH, 1H), 2.42-2.47 (t, CF2CH2,2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 47.9, −105.6

Compound (B1-12): Combination of precursor (Bpre-7) and salt exchange compound K
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.76 (s, ArH, 1H), 8.59-8.64 (m, ArH, 1H), 8.42 (t, ArH, 2H), 8.03-8.19 (m, ArH, 5H), 7.81 (t, ArH, 1H), 7.69 (t, ArH, 2H), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.31-4.58 (m, CH , CF2CH2, 3H), 2.95-3.02 (m, CH, 1H), 1.85-2.05 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) =-62.1, -111.4

Compound (B2-1): Combination of precursor (Bpre-2) and salt exchange compound L
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.50 (d, ArH, 2H), 8.37 (d, ArH, 2H), 7.93 (t, ArH, 2H,), 7.55-7.75 (m, ArH , 7H), 7.01-7.47 (m, ArH, 8H), 4.72 (s, CH, 1H), 4.43 (s, CH, 1H), 4.23, (t, CH2, 2H), 2.95-3.02 (m, CH , 1H), 2.63-2.73, (m, CF2CH2, 2H), 1.86-2.07 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 111.3, −117.4

Compound (B2-4): Combination of precursor (Bpre-6) and salt exchange compound M
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.74-7.90 (m, 15H, ArH), 7.68-7.82 (m, ArH, 6H), 6.60-6.80 (m, ArH, 6H), 5.54 ( s, CH, 1H), 2.42-2.47 (t, CF2CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 105.6

Compound (B2-5): Combination of precursor (Bpre-5) and salt exchange compound O
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.07 (d, ArH, 2H), 7.59-7.75 (m, ArH, 3H), 7.01-7.45 (m, ArH, 8H), 4.71 (s, CH, 1H), 4.44 (s, CH, 1H), 4.31 (s, CH2, 2H), 3.94 (t, SCH2, 2H), 3.71 (d, SCH2, 2H), 2.93-3.00 (m, CH, 1H ), 2.34-2.42 (m, CH2, 2H), 1.80-2.08 (m, CH2, 5H), 0.98-1.03 (m, CH, 1H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 107.9

Compound (B2-6): Combination of precursor (Bpre-5) and salt exchange compound P
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 8.47 (d, ArH, 2H), 7.82-7.90 (m, ArH, 4H), 7.70-7.80 (m, ArH, 2H), 7.58-7.69 ( m, ArH, 3H), 7.00-7.51 (m, ArH, 10H), 4.70 (s, CH, 1H), 4.31-4.58 (m, CH, CF2CH2, ArCH2, 4H), 4.01 (d, ArCH2, 1H) , 2.95-3.02 (m, CH, 1H), 1.85-2.05 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 111.4

Compound (B2-7): Combination of precursor (Bpre-1) and salt exchange compound M
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.74-7.90 (m, 15H, ArH), 7.00-7.48 (m, ArH, 8H), 4.70 (s, CH, 1H), 4.40 (s, CH, 1H), 3.15-3.22 (m, CF2CH, 1H), 1.95-2.15 (m, CH2, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 111.3, −117.4

Compound (D2-4): Combination of precursor (Bpre-8) and salt exchange compound M
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.74-7.90 (m, 15H, ArH), 7.00-7.48 (m, ArH, 8H), 4.85 (s, ArCH, 2H), 3.16 (s, (CH, 2H)

Compound (D1-1): Combination of precursor (Bpre-8) and salt exchange compound N
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.77-7.98 (m, ArH, 11H), 7.00-7.48 (m, ArH, 8H), 4.85 (s, ArCH, 2H), 3.16 (s, (CH, 2H)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 103.9

<Preparation of resist composition>
(Examples 1-14, Comparative Examples 1-8)
The components shown in Tables 1 to 3 were mixed and dissolved to prepare resist compositions of respective examples.

In Tables 1 to 3, each abbreviation has the following meaning. The numerical value in [] is a compounding amount (part by mass).
(A) -1: a polymer compound represented by the following chemical formula (A1) -1. This polymer compound (A1) -1 was obtained by radical polymerization using monomers that induce structural units constituting the polymer compound at a predetermined molar ratio. About this high molecular compound (A1) -1, the weight average molecular weight (Mw) of standard polystyrene conversion calculated | required by GPC measurement is 7700, and molecular weight dispersion degree (Mw / Mn) is 1.72. ^The copolymer composition ratio (ratio (molar ratio) of each structural unit in the structural formula) determined by ¹³ C-NMR is 1 / m / n = 30/60/10.

(A) -2: a polymer compound represented by the following chemical formula (A1) -2. This polymer compound (A1) -2 was obtained by radical polymerization using a monomer that induces a structural unit constituting the polymer compound at a predetermined molar ratio. About this high molecular compound (A1) -2, the weight average molecular weight (Mw) of standard polystyrene conversion calculated | required by GPC measurement is 6400, and molecular weight dispersion degree (Mw / Mn) is 1.66. ^The copolymer composition ratio (ratio (molar ratio) of each structural unit in the structural formula) determined by ¹³ C-NMR is 1 / m = 60/40.

(A) -3: a polymer compound represented by the following chemical formula (A1) -3. This polymer compound (A1) -3 was obtained by radical polymerization using a monomer that induces a structural unit constituting the polymer compound at a predetermined molar ratio. About this high molecular compound (A1) -3, the weight average molecular weight (Mw) of standard polystyrene conversion calculated | required by GPC measurement is 6900, and molecular weight dispersion degree (Mw / Mn) is 1.72. ^The copolymer composition ratio (ratio (molar ratio) of each structural unit in the structural formula) determined by ¹³ C-NMR is 1 / m / n = 30/60/10.

(A) -4: a polymer compound represented by the following chemical formula (A1) -4. The polymer compound (A1) -4 was obtained by radical polymerization using a monomer that induces a structural unit constituting the polymer compound at a predetermined molar ratio. With respect to this polymer compound (A1) -4, the standard polystyrene equivalent weight average molecular weight (Mw) determined by GPC measurement was 7200, and the molecular weight dispersity (Mw / Mn) was 1.69. ^The copolymer composition ratio (ratio (molar ratio) of each structural unit in the structural formula) determined by ¹³ C-NMR is 1 / m = 50/50.

(A) -5: a polymer compound represented by the following chemical formula (A1) -5. The polymer compound (A1) -5 was obtained by radical polymerization using monomers that induce structural units constituting the polymer compound at a predetermined molar ratio. About this high molecular compound (A1) -5, the weight average molecular weight (Mw) of standard polystyrene conversion calculated | required by GPC measurement is 7300, and molecular weight dispersion degree (Mw / Mn) is 1.75. ^The copolymer composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by ¹³ C-NMR is 1 / m = 30/70.

  (B1) -1 to (B1) -12: Respective acid generators comprising the above compound (B1-1) to compound (B1-12).

(B2) -1: An acid generator composed of the following compound (B2-1).
(B2) -2: An acid generator composed of the following compound (B2-2).
(B2) -3: An acid generator composed of the following compound (B2-3).
(B2) -4: An acid generator composed of the following compound (B2-4).
(B2) -5: An acid generator comprising the following compound (B2-5).
(B2) -6: An acid generator comprising the following compound (B2-6).
(B2) -7: An acid generator comprising the following compound (B2-7).

(D2) -1: An acid diffusion controller comprising a compound represented by the following chemical formula (D2-1).
(D2) -2: An acid diffusion controller comprising a compound represented by the following chemical formula (D2-2).
(D2) -3: An acid diffusion controller comprising a compound represented by the following chemical formula (D2-3).
(D2) -4: An acid diffusion controller comprising a compound represented by the following chemical formula (D2-4).
(D1) -1: An acid diffusion controller comprising a compound represented by the following chemical formula (D1-1).
(S) -1: Propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 (mass ratio) mixed solvent.

<Formation of resist pattern>
The resist composition of each example was applied onto an 8-inch silicon substrate subjected to hexamethyldisilazane (HMDS) treatment using a spinner, and prebaked (PAB) at a temperature of 110 ° C. for 60 seconds on a hot plate. By performing the treatment and drying, a resist film having a thickness of 50 nm was formed.
Next, a 1: 1 line and space pattern (hereinafter referred to as a target size) with a line width of 50 nm is applied to the resist film at an acceleration voltage of 100 kV using an electron beam lithography apparatus JEOL-JBX-9300FS (manufactured by JEOL Ltd.). Drawing (exposure) as “LS pattern”) was performed. Thereafter, a post-exposure heating (PEB) treatment was performed at 100 ° C. for 60 seconds.
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 Ohka Kogyo Co., Ltd.).
Thereafter, water rinsing was performed for 15 seconds using pure water.
As a result, a 1: 1 LS pattern with a line width of 50 nm was formed.

[Evaluation of optimum exposure (Eop)]
The optimum exposure dose Eop (μC / cm ² ) at which a target-sized LS pattern was formed by the resist pattern forming method was determined. This is shown in Tables 4 to 6 as “Eop (μC / cm ² )”.

[Evaluation of LWR (Line Width Roughness)]
With respect to the LS pattern formed in the above <Resist pattern formation>, 3σ, which is a measure indicating LWR, was obtained. This is shown in Tables 4 to 6 as “LWR (nm)”.
“3σ” is a standard deviation obtained by measuring 400 line positions in the longitudinal direction of the line with a scanning electron microscope (acceleration voltage: 800 V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation). A triple value (3σ) (unit: nm) of (σ) is shown.
The smaller the value of 3σ, the smaller the roughness of the line side wall, which means that an LS pattern with a more uniform width was obtained.

  From the results shown in Tables 4 to 6, according to the resist composition of the example to which the present invention is applied, a resist pattern having a good shape with improved sensitivity and reduced roughness can be formed in the formation of the resist pattern. I can confirm that I can do it.

Claims (15)

A resist composition that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid,
A base component (A) whose solubility in a developer is changed by the action of an acid;
A compound (BD1) composed of an anion portion and a cation portion, represented by the following general formula (bd1);
A resist composition containing:

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ] 2. The resist composition according to claim 1, wherein the cation moiety in the compound (BD1) is a cation represented by any one of the following general formulas (ca-1) to (ca-4).

[Wherein, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² each independently have an aryl group which may have a substituent, an alkyl group which may have a substituent, or a substituent. Represents a good alkenyl group. R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ , and R ^{211 to} R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, or may be bonded to each other to form a ring together with the sulfur atom in the formula. R ²¹⁰ may have an aryl group that may have a substituent, an alkyl group that may have a substituent, an alkenyl group that may have a substituent, or —SO ₂ — that may have a substituent. It is a containing cyclic group. Provided ^that at least one of R 201 ^{to R 203,} at least one of ^{R 204} and ^{R 205,} at least one of ^{R 206} and ^{R 207,} as well as at least one of ^{R 211} and ^{R 212} are substituents As an electron withdrawing group. L ²⁰¹ represents —C (═O) — or —C (═O) —O—. A plurality of Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group. x is 1 or 2. W ²⁰¹ represents a (x + 1) -valent linking group. ]   The resist composition according to claim 1, wherein the electron withdrawing group is a halogen atom or a halogenated alkyl group. 4. The structure according to claim 1, wherein at least one of Rx ^{1 to} Rx ² and at least one of Rx ^{3 to} Rx ⁴ are bonded to each other to form a ring structure. The resist composition described in 1. The resist composition as described in any one of Claims 1-4 whose anion part in the said compound (BD1) is an anion represented by the following general formula (bd1-an1).

[Wherein, Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent. Rx ^{7 to} Rx ⁸ each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure. p is 1 or 2, and when p = 2, the plurality of Rx ⁷ to Rx ⁸ may be different from each other. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more. ] The resist composition according to claim 5, wherein the anion moiety in the compound (BD1) is an anion represented by the following general formula (bd1-an2).

[Wherein, Rx ^{5 to} Rx ⁶ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent. A plurality of Rx ⁷ to Rx ⁸ each independently represents a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more may be bonded to each other to form a ring structure. . Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{5 to} Rx ⁸ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion portion becomes an n-valent anion. n is an integer of 1 or more. ] The resist composition according to claim 1, wherein Ry ^{1 to} Ry ² are bonded to each other to form a ring structure. Wherein Rx ⁷ to Rx ⁸ forms a ring structure with each other, the resist composition according to any one of claims 5-7. The resist composition according to claim 1, wherein two or more of Rz ^{1 to} Rz ⁴ are bonded to each other to form a ring structure. The resist composition according to claim 1, wherein at least one of Rz ^{1 to} Rz ⁴ has an anion group. At least one of the ^Rx 5 to Rx ⁶ has an anionic group, the resist composition according to any one of claims 5-10.   A step of forming a resist film on the support using the resist composition according to any one of claims 1 to 11, a step of exposing the resist film, and a developing of the resist film after the exposure A resist pattern forming method comprising a step of forming a resist pattern.   The resist pattern forming method according to claim 12, wherein in the step of exposing the resist film, the resist film is exposed to EUV (extreme ultraviolet) or EB (electron beam). The compound which consists of an anion part and a cation part represented by the following general formula (bd1).

[Wherein, Rx ^{1 to} Rx ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them are bonded to each other to form a ring structure Also good. Ry ^{1 to} Ry ² each independently represent a hydrocarbon group or a hydrogen atom that may have a substituent, or may be bonded to each other to form a ring structure.

Is a double bond or a single bond. Rz ^{1 to} Rz ⁴ each independently represent a hydrocarbon group or a hydrogen atom which may have a substituent, or two or more of them may form a ring structure when the valence permits. You may do it. However, at least one of Rx ^{1 to} Rx ⁴ , Ry ^{1 to} Ry ^2, and Rz ^{1 to} Rz ⁴ has an anion group, and the entire anion part becomes an n-valent anion. n is an integer of 1 or more. m is an integer of 1 or more, and M ^{m +} represents an m-valent organic cation having an electron withdrawing group. ]   The acid generator which consists of a compound of Claim 14.