Resist composition, resist pattern formation method, compound, and polymer compound

Abstract

Provided is a resist composition which generates an acid upon exposure to light, and the solubility of which in a developer solution is changed by the action of an acid. The resist composition contains a resin component (A1), the solubility of which in a developer solution is changed by the action of an acid, wherein the component (A1) has a constituent unit (a0) that is derived from a compound represented by formula (a0-m). In formula (a0-m), Ar01 to Ar03 each represent an aromatic ring; m01 to m03 each represent an integer of 0 or more; m01 + m02 + m03 ≥ 1; Rc01 to Rc03 each represent a substituent other than a cyano group; k01 to k03 each represent an integer of 0 or more; Z02 and Z03 each represent a substituent other than a cyano group or a hydrogen atom, or are bonded to each other to form a single bond or a divalent linking group; W0 represents a polymerizable group-containing group; and Y0 represents a divalent linking group.

Description

Resist composition, resist pattern formation method, compound, polymer compound

[0001] The present invention relates to a resist composition, a resist pattern forming method, a compound, and a polymer compound. This application claims priority under Japanese Patent Application No. 2025-068036, filed in Japan on April 17, 2025, the contents of which are incorporated herein by reference.

[0002] In recent years, advances in lithography technology have led to rapid miniaturization of patterns in the manufacturing of semiconductor devices and liquid crystal display elements. Generally, miniaturization is achieved by shortening the wavelength (increasing the energy) of the exposure light source.

[0003] Resist materials are required to possess lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing patterns of fine dimensions. Conventionally, chemically amplified resist compositions have been used as resist materials that satisfy these requirements, containing a base component whose solubility in the developer solution changes due to the action of acid, and an acid generator component that generates acid upon exposure.

[0004] In chemically amplified resist compositions, resins having multiple structural units are generally used as the substrate component to improve lithography properties. Furthermore, in the formation of resist patterns, the behavior of acids generated from acid generator components upon exposure is also considered a factor that significantly affects lithography properties. A wide variety of acid generators have been proposed for use in chemically amplified resist compositions. For example, onium salt-based acid generators such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generators, diazomethane-based acid generators, nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators are known.

[0005] For example, Patent Document 1 discloses a resist composition that employs a compound in which an electron-withdrawing group is introduced to a sulfonium cation as an acid generator.

[0006] Japanese Patent Publication No. 2019-207404

[0007] As resist patterns become finer, for example, EUV and EB lithography aim to form patterns as small as tens of nanometers. With this miniaturization of resist patterns, improving lithographic properties such as sensitivity and roughness has become a challenge. However, these lithographic properties are usually in a trade-off relationship; improving one tends to degrade the others. In resist compositions, it is required to improve both sensitivity and roughness without creating a trade-off. Furthermore, improving etching resistance is also a challenge due to the thinning of the resist film associated with finer patterns.

[0008] The present invention has been made in view of the above circumstances, and aims to provide a resist composition that can be made highly sensitive in the formation of a resist pattern, has good lithography characteristics such as roughness, and has excellent etching resistance, a method for forming a resist pattern using the resist composition, a compound that can be used in the resist composition, and a polymer compound having a constituent unit derived from the compound.

[0009] 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 acid upon exposure and whose solubility in a developer changes due to the action of the acid, the resist composition containing a resin component (A1) whose solubility in a developer changes due to the action of the acid, wherein the resin component (A1) has a constituent unit (a0) derived from a compound represented by the following general formula (a0-m).

[0010] [In the formula, Ar ０１ Ar ０２ and Ar ０３ Each of these independently represents an aromatic ring. m01, m02, and m03 each independently represent an integer greater than or equal to 0, as far as the valence allows, and m01 + m02 + m03 ≥ 1. Rc ０１ , Rc ０２ , and Rc ０３each independently represents a substituent other than a cyano group. k01, k02, and k03 each independently represent an integer of 0 or more as long as the valency allows. When k01 is an integer of 2 or more, 2 or more Rc ０１ may be the same as or different from each other. When k02 is an integer of 2 or more, 2 or more Rc ０２ may be the same as or different from each other. When k03 is an integer of 2 or more, 2 or more Rc ０３ may be the same as or different from each other. Z ０２ and Z ０３ each independently represent a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ are bonded to each other to form a single bond or a divalent linking group. W ０ represents a polymerizable group-containing group. Y ０ represents a divalent linking group.]

[0011] A second aspect of the present invention is a resist pattern forming method comprising: a step of forming a resist film on a support using the resist composition according to the first aspect; a step of exposing the resist film; and a step of developing the exposed resist film to form a resist pattern.

[0012] A third aspect of the present invention is a compound represented by the following general formula (a0-m).

[0013] [In the formula, Ar ０１ , Ar ０２ and Ar ０３ each independently represent an aromatic ring. m01, m02, and m03 each independently represent an integer of 0 or more as long as the valency allows, and m01+m02+m03≧1. Rc ０１ , Rc ０２ , and Rc ０３ each independently represent a substituent other than a cyano group. k01, k02, and k03 each independently represent an integer of 0 or more as long as the valency allows. When k01 is an integer of 2 or more, 2 or more Rc ０１ may be the same as or different from each other. When k02 is an integer of 2 or more, 2 or more Rc ０２They may be the same or different from each other. If k03 is an integer of 2 or more, then Rc must be 2 or more. ０３ They may be the same or different from each other. Z ０２ and Z ０３ Each of these independently represents a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ These bonds to each other, forming single bonds or divalent linking groups. ０ This represents a polymerizable group-containing group. ０ This represents a divalent linking group.

[0014] A fourth aspect of the present invention is a polymer compound having a structural unit derived from the compound according to the third aspect.

[0015] According to the present invention, it is possible to provide a resist composition that enables high sensitivity in resist pattern formation, has good lithography characteristics such as roughness, and has excellent etching resistance, a method for forming a resist pattern using the resist composition, a compound that can be used in the resist composition, and a polymer compound having a constituent unit derived from the compound.

[0016] In this specification and in these claims, “aliphatic” is defined as a concept relative to aromatic, meaning a group, compound, etc. that does not possess aromaticity. Unless otherwise specified, “alkyl group” includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to alkyl groups in alkoxy groups. Unless otherwise specified, “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups. “Halogen atom” includes fluorine, chlorine, bromine, and iodine atoms. “Constituent unit” means a monomer unit (monomer unit) that constitutes a polymer compound (resin, polymer, copolymer). When it is stated that “may have substituents,” this refers to the substitution of a hydrogen atom (-H) with a monovalent group, or a methylene group (-CH ２This includes both cases where the methylene group (-H) is substituted with a divalent group. That is, when a monovalent group is listed as the substituent, it means that a hydrogen atom (-H) is substituted. Also, when a divalent group is listed as the substituent, it means that the methylene group (-CH) is substituted. ２ This means substituting a hydrogen atom. Examples of monovalent groups that substitute for a hydrogen atom include, but are not limited to, alkyl groups, alkoxy groups, halogen atoms, alkyl halides, and hydroxyl groups. Examples of divalent groups that substitute for a methylene group include, but are not limited to, carbonyl groups, ether bonds, ester bonds, and amide bonds. "Exposure" is a concept that includes all forms of radiation irradiation.

[0017] An "acid-degradable group" is a group that is acid-degradable, meaning that at least some of the bonds in its structure can be cleaved by the action of an acid. Examples of acid-degradable groups whose polarity increases by the action of an acid include groups that decompose to produce polar groups by the action of an acid. Examples of polar groups include carboxyl groups, hydroxyl groups, amino groups, and sulfo groups (-SO4). ３ Examples include H). More specifically, examples of acid-degradable groups include groups in which the polar group is protected by an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group).

[0018] An "acid-dissociable group" refers to both (i) a group that has acid-dissociability, in which the bond between the acid-dissociable group and an adjacent atom can be cleaved by the action of an acid, and (ii) a group in which, after some of the bonds are cleaved by the action of an acid, a decarboxylation reaction occurs, further cleaving of the bond between the acid-dissociable group and an adjacent atom. The acid-dissociable group constituting the acid-degradable group must be a group with lower polarity than the polar group generated by the dissociation of the acid-dissociable group. As a result, when the acid-dissociable group dissociates by the action of an acid, a polar group with higher polarity than the acid-dissociable group is generated, increasing the polarity. Consequently, the overall polarity of component (A1) increases. This increase in polarity relatively changes the solubility in the developer; solubility increases when the developer is an alkaline developer, and decreases when the developer is an organic developer.

[0019] "Base material components" are organic compounds that have film-forming ability. Organic compounds used as base material components are broadly classified into nonpolymers and polymers. Nonpolymers typically have a molecular weight of 500 or more and less than 4000. Hereinafter, "low molecular weight compounds" refer to nonpolymers with a molecular weight of 500 or more and less than 4000. Polymers typically have a molecular weight of 1000 or more. Hereinafter, "resins," "high molecular weight compounds," or "polymers" refer to polymers with a molecular weight of 1000 or more. The molecular weight of polymers shall be the weight-average molecular weight on a polystyrene basis calculated by GPC (gel permeation chromatography).

[0020] "Induced structural unit" means a structural unit formed by the cleavage of multiple bonds between carbon atoms, such as an ethylenic double bond. "Acrylic acid ester" may have a hydrogen atom bonded to the α-carbon atom substituted with a substituent. A substituent (R) that substitutes the hydrogen atom bonded to the α-carbon atom. αｘ ) is an atom or group other than a hydrogen atom. Also, substituents (R αｘ Itaconic acid diesters in which the substituent (R) is substituted with substituents containing an ester bond, or substituents (R αｘ This also includes α-hydroxyacrylic esters in which the α-carbon atom is substituted with a hydroxyalkyl group or a group that modifies its hydroxyl group. Unless otherwise specified, the α-carbon atom of an acrylic acid ester refers to the carbon atom to which the carbonyl group of acrylic acid is bonded. Hereinafter, an acrylic acid ester in which the hydrogen atom bonded to the α-carbon atom is substituted with a substituent may be called an α-substituted acrylic acid ester.

[0021] The term "derivative" is defined as a compound in which the α-position hydrogen atom of the target compound is substituted with another substituent such as an alkyl group or alkyl halide, and includes derivatives thereof. Examples of such derivatives include those in which the hydrogen atom of the hydroxyl group of the target compound, which may have the α-position hydrogen atom substituted with a substituent, is substituted with an organic group; and those in which a substituent other than a hydroxyl group is bonded to the target compound, which may have the α-position hydrogen atom substituted with a substituent. Unless otherwise specified, the α-position refers to the first carbon atom adjacent to the functional group. Examples of substituents that substitute the α-position hydrogen atom of hydroxystyrene include R αｘ Similar examples include the above.

[0022] In this specification and within the scope of these claims, some structures represented by chemical formulas may contain a chiral carbon, and may have enantiomers or diastereomers. In such cases, a single chemical formula will represent all of these isomers. These isomers may be used individually or as a mixture.

[0023] (Resist Composition) The resist composition of this embodiment generates acid upon exposure and changes in solubility in a developer solution due to the action of the acid. Such a resist composition contains a base component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer solution changes due to the action of the acid. In the resist composition of this embodiment, component (A) includes a resin component (A1) which generates acid upon exposure and changes in solubility in a developer solution due to the action of the acid.

[0024] When a resist film is formed using the resist composition of this embodiment and selective exposure is performed on the resist film, acid is generated from the resin component (A1) in the exposed areas of the resist film. Due to the action of this acid, the solubility of component (A) in the developer changes, while the solubility of component (A) in the developer does not change in the unexposed areas of the resist film. As a result, a difference in solubility in the developer occurs between the exposed and unexposed areas. Therefore, when the resist film is developed, if the resist composition is positive type, the exposed areas of the resist film are dissolved and removed to form a positive type resist pattern, and if the resist composition is negative type, the unexposed areas of the resist film are dissolved and removed to form a negative type resist pattern.

[0025] The resist composition of this embodiment may be a positive-type resist composition or a negative-type resist composition. Furthermore, the resist composition of this embodiment may be for an alkaline development process that uses an alkaline developer for the development process during resist pattern formation, or for a solvent development process that uses a developer containing an organic solvent (organic developer) for the development process.

[0026] <Substrate component (A)> In the resist composition of this embodiment, component (A) includes a resin component (A1) (hereinafter also referred to as "component (A1)") whose solubility in the developer solution changes due to the action of an acid. By using component (A1), the polarity of the substrate component changes before and after exposure, so that good development contrast can be obtained not only in the alkaline development process but also in the solvent development process. As component (A), other polymer compounds and / or low molecular weight compounds may be used in combination with component (A1).

[0027] In the resist composition of this embodiment, component (A) may be used alone or in combination of two or more types.

[0028] • About component (A1) Component (A1) is a resin component whose solubility in the developer changes due to the action of an acid. Component (A1) has a constituent unit (a0) derived from a compound represented by the general formula (a0-m) described below.

[0029] <<Constituent Unit (a0)>> The constituent unit (a0) is derived from the compound represented by the following general formula (a0-m).

[0030] [In the formula, Ar ０１ Ar ０２ and Ar ０３ Each of these independently represents an aromatic ring. m01, m02, and m03 each independently represent an integer greater than or equal to 0, as far as the valence allows, and m01 + m02 + m03 ≥ 1. Rc ０１ , Rc ０２ , and Rc ０３ Each of these independently represents a substituent other than a cyano group. k01, k02, and k03 each independently represent an integer of 0 or more, as long as the valency allows. If k01 is an integer of 2 or more, then Rc of 2 or more. ０１ They may be the same or different from each other. If k02 is an integer of 2 or more, then Rc must be 2 or more. ０２ They may be the same or different from each other. If k03 is an integer of 2 or more, then Rc must be 2 or more. ０３ They may be the same or different from each other. Z ０２ and Z ０３ Each of these independently represents a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ These bonds to each other, forming single bonds or divalent linking groups. ０ This represents a polymerizable group-containing group. ０ This represents a divalent linking group.

[0031] {Cation part}

[0032] In the above general formula (a0-m), Ar ０１ Ar ０２ and Ar ０３The aromatic rings in are not particularly limited as long as they are cyclic conjugated systems each independently having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. As for the aromatic ring, aromatic hydrocarbon rings are preferred, aromatic hydrocarbon rings with 6 to 15 carbon atoms are more preferred, benzene or naphthalene are even more preferred, and benzene is particularly preferred. ０１ Ar ０２ and Ar ０３ In this mixture, it is particularly preferable that all aromatic rings are benzene rings.

[0033] In the above general formula (a0-m), from the viewpoint of further improving etching resistance, it is preferable that m01 + m02 + m03 ≥ 2, more preferably that m01 + m02 + m0 = 2, and even more preferably that one of m01, m02, and m03 is 0 and the remaining two are each 1.

[0034] In the above general formula (a0-m), Rc ０１ , Rc ０２ , and Rc ０３ Examples include electron-withdrawing groups other than cyano groups, alkyl groups, amino groups, groups represented by the following general formulas (ca-r-1) to (ca-r-8), and acid-degradable groups.

[0035] [In the formula, R' ２０１ Each of these is independently a hydrogen atom, an optionally substituted cyclic group, an optionally substituted linear alkyl group, or an optionally substituted linear alkenyl group. * is Ar in the general formula (a0-m).０１ Ar ０２ or Ar ０３ This shows the combination.

[0036] Rc ０１ , Rc ０２ , and Rc ０３ The alkyl group in Rc is preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. ０１ , Rc ０２ , and Rc ０３ The alkyl group in Rc may be linear or branched. ０１ , Rc ０２ , and Rc ０３ Specific examples of alkyl groups in Rc include methyl group, ethyl group, n-propyl group, isopropyl group, etc. Among these, Rc ０１ , Rc ０２ , and Rc ０３ A methyl group is preferred as the alkyl group in this case.

[0037] Rc ０１ , Rc ０２ , and Rc ０３ Examples of electron-withdrawing groups other than cyano groups include halogen atoms, alkyl halides, alkoxy halides, nitro groups, alkylsulfonyl groups, and arylsulfonyl groups. Halogen atoms or alkyl halides are preferred as electron-withdrawing groups. From the viewpoint of improving sensitivity, iodine atoms are preferred as halogen atoms. From the viewpoint of improving LWR, fluorine atoms are preferred. Examples of alkyl halides include groups in which some or all of the hydrogen atoms of the C1-C10 alkyl group are substituted with halogen atoms. ０１ , Rc ０２ , and Rc ０３ A trifluoromethyl group is preferred as the alkyl halogen in this case.

[0038] In the above formulas (ca-r-1) to (ca-r-8), R' ２０１ This is a hydrogen atom, a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents.

[0039] A cyclic group which may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferred to be saturated.

[0040] R' ２０１ The aromatic hydrocarbon group in R' is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this carbon number does not include the carbon atoms in substituents. ２０１ Specific examples of aromatic rings in aromatic hydrocarbon groups include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, nitrogen atoms, etc. ２０１ Specific examples of aromatic hydrocarbon groups in this context include groups obtained by removing one hydrogen atom from the aromatic ring (aryl groups: e.g., phenyl group, naphthyl group, etc.), and groups in which one of the hydrogen atoms of the aromatic ring is replaced by an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0041] R' ２０１The cyclic aliphatic hydrocarbon group in may include an aliphatic hydrocarbon group having a ring in its structure. Examples of the aliphatic hydrocarbon group having a ring in the structure include an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched 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 obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ decane, tetracyclododecane and the like, polycycloalkanes having a bridged ring polycyclic skeleton; and polycycloalkanes having a condensed ring polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferable.

[0042] Among them, as the cyclic aliphatic hydrocarbon group in R' ２０１ , a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane is preferable, a group obtained by removing one hydrogen atom from a polycycloalkane is more preferable, an adamantyl group and a norbornyl group are particularly preferable, and an adamantyl group is most preferable.

[0043] The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, and specific examples thereof include a methylene group [-CH ２-], ethylene group [-(CH ２ ) ２ -], trimethylene group [-(CH ２ ) ３ -], tetramethylene group [-(CH ２ ) ４ -], pentamethylene group [-(CH ２ ) ５ -] and the like. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples include -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 - and other alkylmethylene groups; -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 - and other alkylethylene groups; -CH(CH ３ )CH ２ CH ２ -, -CH ２ CH(CH ３ )CH ２ - and other alkyltrimethylene groups; -CH(CH ３ )CH ２ CH ２ CH ２ -, -CH ２ CH(CH ３ )CH ２ CH ２Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0044] Also, R' ２０１ The cyclic hydrocarbon group in may contain heteroatoms, such as heterocycles. Specifically, lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7) described below, and -SO groups represented by the general formulas (b5-r-1) to (b5-r-4) described below. ２ - Examples include cyclic groups and heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16).

[0045]

[0046] R' ２０１ Examples of substituents on the cyclic group include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, and nitro groups. Preferred alkyl groups as substituents are alkyl groups having 1 to 5 carbon atoms, with methyl, ethyl, propyl, n-butyl, and tert-butyl groups being the most preferred. Preferred alkoxy groups as substituents are alkoxy groups having 1 to 5 carbon atoms, with methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, and tert-butoxy groups being more preferred, with methoxy and ethoxy groups being the most preferred. Preferred halogen atoms as substituents are fluorine atoms. Examples of alkyl halides as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms are substituted with the halogen atoms. Carbonyl groups as substituents are methylene groups (-CH) that constitute the cyclic hydrocarbon group. ２ It is a substituting group for -).

[0047] A chain-like alkyl group which may have substituents: R' ２０１The linear alkyl group in the formula may be linear or branched. Linear alkyl groups preferably have 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, even more preferably 1 to 10 carbon atoms, particularly preferably 1 to 3 carbon atoms, and most preferably a methyl group. Branched alkyl groups preferably have 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and even more preferably 3 to 10 carbon atoms. Specific examples of branched alkyl groups include, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

[0048] A chain-like alkenyl group which may have substituents: R' ２０１ The linear alkenyl group may be linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, even more preferably 2 to 4 carbon atoms, and particularly preferably 3 carbon atoms. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Examples of branched alkenyl groups include 1-methylvinyl groups, 2-methylvinyl groups, 1-methylpropenyl groups, and 2-methylpropenyl groups. Among the linear alkenyl groups listed above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0049] R' ２０１ Examples of substituents in the chain-like alkyl or alkenyl group include alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, amino groups, and the above R'. ２０１ Examples include cyclic groups in this context.

[0050] R' ２０１The optionally substituted cyclic groups, optionally substituted linear alkyl groups, or optionally substituted linear alkenyl groups include, in addition to those mentioned above, the same as the acid-dissociable group represented by formula (a1-r-2) described later, as optionally substituted cyclic groups or optionally substituted linear alkyl groups.

[0051] R' ２０１ Of the above, hydrogen atoms or linear alkyl groups are preferred, hydrogen atoms or linear alkyl groups having 1 to 3 carbon atoms are more preferred, hydrogen atoms or methyl groups are more preferred, and methyl groups are even more preferred.

[0052] Rc ０１ , Rc ０２ , and Rc ０３ In the above, the group represented by the general formula (ca-r-1) to (ca-r-8) is preferably the group represented by the general formula (ca-r-1) or (ca-r-8), and more preferably a hydroxyl group, a methyl group, or a methoxy group.

[0053] Rc ０１ , Rc ０２ , and Rc ０３ Examples of acid-degradable groups in this context include groups in which a polar group is protected by an acid-dissociating group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected by an acid-dissociating group).

[0054] Examples of acid-dissociable groups include those previously proposed as acid-dissociable groups for base resins used in chemically amplified resist compositions. Specifically, examples of acid-dissociable groups proposed for base resins used in chemically amplified resist compositions include the following: "acetal-type acid-dissociable groups," "tertiary alkyl ester-type acid-dissociable groups," "tertiary alkyloxycarbonyl acid-dissociable groups," and "secondary alkyl ester-type acid-dissociable groups."

[0055] Acetal-type acid-dissociating group: Among the polar groups, an example of an acid-dissociating group that protects a carboxyl group or a hydroxyl group is the acid-dissociating group represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as an "acetal-type acid-dissociating group").

[0056] [In the formula, Ra'１ , Ra' ２ Ra' is a hydrogen atom or an alkyl group. ３ is a hydrocarbon group, Ra' ３ Ra' １ , Ra' ２ It may combine with any of the following to form a ring.

[0057] In formula (a1-r-1), Ra' １ and Ra' ２ Preferably, at least one of them is a hydrogen atom, and more preferably, both are hydrogen atoms. １ Or Ra' ２ If the alkyl group is an alkyl group, the alkyl group can be the same as those listed in the description of the α-substituted acrylic acid ester above as substituents that may be bonded to the carbon atom at the α position, and an alkyl group having 1 to 5 carbon atoms is preferred. Specifically, linear or branched alkyl groups are preferred. More specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc., with methyl group or ethyl group being more preferred, and methyl group being particularly preferred.

[0058] In formula (a1-r-1), Ra' ３ Examples of hydrocarbon groups include linear or branched alkyl groups, or cyclic hydrocarbon groups. The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specifically, examples include methyl groups, ethyl groups, n-propyl groups, n-butyl groups, and n-pentyl groups. Among these, methyl groups, ethyl groups, or n-butyl groups are preferred, and methyl groups or ethyl groups are more preferred.

[0059] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., with isopropyl group being preferred.

[0060] Ra' ３ When the hydrocarbon group is cyclic, it may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic or monocyclic group. As a monocyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. As a polycyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a polycycloalkane is preferred, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include decane and tetracyclododecane.

[0061] Ra' ３ When a cyclic hydrocarbon group becomes an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. ３Specific examples of aromatic hydrocarbon groups in this context include: a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0062] Ra' ３ The cyclic hydrocarbon group in may have substituents. Examples of substituents include -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, -R Ｐ２ -CN or -R Ｐ２ -COOH (These substituents are collectively referred to as "Ra ｘ５ It is also called "." ) are some examples. Here, R Ｐ１ This is a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Also, R Ｐ２ R 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 aromatic hydrocarbon group having 6 to 30 carbon atoms. However, R Ｐ１ and R Ｐ２Some or all of the hydrogen atoms in the chain-like saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group may be substituted with fluorine atoms. The aliphatic cyclic hydrocarbon group may have one or more of the substituents individually, or it may have one or more of each of the substituents. Examples of monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups. Examples of monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl groups; and polycyclic aliphatic saturated hydrocarbon groups such as bicyclo[2.2.2]octanyl, tricyclo[5.2.1.02,6]decanyl, tricyclo[3.3.1.13,7]decanyl, tetracyclo[6.2.1.13,6.02,7]dodecanyl, and adamantyl groups. Examples of monovalent aromatic hydrocarbon groups 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.

[0063] Ra' ３ But, Ra' １ , Ra' ２ When the cyclic group is bonded to any of the above 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.

[0064] Tertiary alkyl ester type acid-dissociating groups: Among the polar groups mentioned above, an example of an acid-dissociating group that protects a carboxyl group is the acid-dissociating group represented by the following general formula (a1-r-2). Of the acid-dissociating groups represented by the following formula (a1-r-2), those composed of alkyl groups may hereafter be referred to as "tertiary alkyl ester type acid-dissociating groups" for convenience.

[0065] [In the formula, Ra' ４ ~Ra'６ Each of these is a hydrocarbon group, Ra' ５ , Ra' ６ They may be joined to each other to form a ring.

[0066] Ra' ４ Examples of hydrocarbon groups include linear or branched alkyl groups, linear or cyclic alkenyl groups, or cyclic hydrocarbon groups. ４ In the above, linear or branched alkyl groups, cyclic hydrocarbon groups (monocyclic aliphatic hydrocarbon groups, polycyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups) are defined as Ra' ３ Similar examples include Ra' ４ The linear or cyclic alkenyl group in Ra' is preferably an alkenyl group having 2 to 10 carbon atoms. ５ , Ra' ６ The hydrocarbon group is the Ra' mentioned above. ３ Similar examples include the above.

[0067] Ra' ５ and Ra' ６ When these groups bond to each other to form a ring, the following groups are preferably represented by the general formula (a1-r2-1), the general formula (a1-r2-2), and the general formula (a1-r2-3). On the other hand, Ra' ４ ~Ra' ６ When these are independent hydrocarbon groups that are not bonded to each other, the groups represented by the following general formula (a1-r2-4) are preferred.

[0068] [In formula (a1-r2-1), Ra' １０ This represents a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with halogen atoms or heteroatom-containing groups. １１ Ra' １０ This indicates a group that forms an aliphatic cyclic group together with the bonded carbon atom. 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 in this cyclic hydrocarbon group may be substituted. Ra １０１ ~Ra １０３Each of these is independently a hydrogen atom, a monovalent linear 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 in these linear saturated hydrocarbon groups and aliphatic cyclic saturated hydrocarbon groups may be substituted. Ra １０１ ~Ra １０３ Two or more of these may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra １０４ is an aromatic hydrocarbon group which may have substituents. In formula (a1-r2-4), Ra' １２ and Ra' １３ Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Ra' １４ This is a hydrocarbon group that may have substituents. * indicates a bond (the same applies hereafter).

[0069] In the above formula (a1 - r2 - 1), Ra' １０ This is a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with halogen atoms or heteroatom-containing groups.

[0070] Ra' １０ In this context, the linear alkyl group has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. １０ In this, the branched alkyl group is the Ra' ３ Similar examples include the above.

[0071] Ra' １０In this context, the alkyl group may be partially substituted with a halogen atom or a heteroatom-containing group. For example, some of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. Also, some of the carbon atoms constituting the alkyl group (such as a methylene group) may be substituted with a heteroatom-containing group. Examples of heteroatoms here include oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of heteroatom-containing groups include (-O-), -C(=O)-O-, -O-C(=O)-, -C(=O)-NH-, -NH-, -S-, and -S(=O). ２ -, -S (=O) ２ Examples include -O-, etc.

[0072] In formula (a1-r2-1), Ra' １１ (Ra' １０ The aliphatic cyclic group formed with the bonded carbon atom is Ra' in formula (a1-r-1). ３ The aliphatic hydrocarbon groups (alicyclic hydrocarbon groups) listed above, which are monocyclic or polycyclic groups, are preferred. Among these, monocyclic alicyclic hydrocarbon groups are preferred, and specifically, cyclopentyl groups and cyclohexyl groups are more preferred.

[0073] In formula (a1-r2-2), the cyclic hydrocarbon group formed by Xa together with Ya is Ra' in formula (a1-r-1). ３ Examples include a group obtained by further removing one or more hydrogen atoms from a cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) in the above. The cyclic hydrocarbon group formed by Xa together with Ya may have substituents. An example of such substituent is the above Ra'. ３ Examples include substituents similar to those that may be present on the cyclic hydrocarbon group in formula (a1-r2-2). １０１ ~Ra １０３ Examples of monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups. １０１ ~Ra １０３Examples of monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl groups; bicyclo[2.2.2]octanyl, tricyclo[5.2.1.0 ２，６ ] Decanyl group, tricyclo[3.3.1.1 ３，７ ] Decanyl group, tetracyclo[6.2.1.1 ３，６ . 0 ２，７ Examples include polycyclic aliphatic saturated hydrocarbon groups such as dodecanyl groups and adamantyl groups. １０１ ~Ra １０３ Of these, from the viewpoint of ease of synthesis, hydrogen atoms and monovalent chain saturated hydrocarbon groups having 1 to 10 carbon atoms are preferred, and among these, hydrogen atoms, methyl groups, and ethyl groups are more preferred, with hydrogen atoms being particularly preferred.

[0074] The above Ra １０１ ~Ra １０３ Examples of substituents on a chain-like saturated hydrocarbon group or an aliphatic cyclic saturated hydrocarbon group represented by the above Ra ｘ５ Similar bases can be cited.

[0075] Ra １０１ ~Ra １０３ Groups containing a carbon-carbon double bond formed by the bonding of two or more carbon atoms to each other to form a cyclic structure include, for example, cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, cyclopentylideneethenyl group, and cyclohexyllideneethenyl group. Among these, cyclopentenyl group, cyclohexenyl group, and cyclopentylideneethenyl group are preferred from the viewpoint of ease of synthesis.

[0076] In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is Ra' in formula (a1-r-1). ３ The groups listed as aliphatic hydrocarbon groups that are monocyclic or polycyclic are preferred. In formula (a1-r2-3), Ra １０４Aromatic hydrocarbon groups in this context include groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among these, Ra １０４ The group is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms with one or more hydrogen atoms removed, more preferably a group from benzene, naphthalene, anthracene, or phenanthrene with one or more hydrogen atoms removed, even more preferably a group from benzene, naphthalene, or anthracene with one or more hydrogen atoms removed, particularly preferably a group from benzene or naphthalene with one or more hydrogen atoms removed, and most preferably a group from benzene with one or more hydrogen atoms removed.

[0077] Ra in equation (a1-r2-3) １０４ Examples of substituents that may be present include methyl groups, ethyl groups, propyl groups, hydroxyl groups, carboxyl groups, halogen atoms, alkoxy groups (such as methoxy groups, ethoxy groups, propoxy groups, butoxy groups, etc.), and alkyloxycarbonyl groups.

[0078] In formula (a1-r2-4), Ra' １２ and Ra' １３ Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. １２ and Ra' １３ In this, the monovalent chain-like saturated hydrocarbon group having 1 to 10 carbon atoms is the above Ra １０１ ~Ra １０３ Examples include monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Ra' １２ and Ra' １３ Among these, alkyl groups having 1 to 5 carbon atoms are preferred, alkyl groups having 1 to 5 carbon atoms are more preferred, methyl groups and ethyl groups are even more preferred, and methyl groups are particularly preferred. １２ and Ra' １３ When a chain-like saturated hydrocarbon group represented by is substituted, the substituent may be, for example, the above-mentioned Ra ｘ５ Similar bases can be cited.

[0079] In formula (a1-r2-4), Ra' １４Ra' is a hydrocarbon group that may have substituents. １４ Examples of hydrocarbon groups in this context include linear or branched alkyl groups, or cyclic hydrocarbon groups.

[0080] Ra' １４ The linear alkyl group in this compound preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and even more preferably 1 or 2. Specifically, examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. Among these, methyl group, ethyl group, or n-butyl group is preferred, and methyl group or ethyl group is more preferred.

[0081] Ra' １４ The branched alkyl group in the compound preferably has 3 to 10 carbon atoms, and more preferably 3 to 5. Specifically, examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., with isopropyl group being preferred.

[0082] Ra' １４ When the hydrocarbon group is cyclic, it may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic or monocyclic group. As a monocyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. As a polycyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a polycycloalkane is preferred, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include decane and tetracyclododecane.

[0083] Ra' １４ As for aromatic hydrocarbon groups in this context, Ra １０４ Examples include those similar to aromatic hydrocarbon groups in [the text]. Among them, Ra' １４The group is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms with one or more hydrogen atoms removed, more preferably a group from benzene, naphthalene, anthracene, or phenanthrene with one or more hydrogen atoms removed, even more preferably a group from benzene, naphthalene, or anthracene with one or more hydrogen atoms removed, particularly preferably a group from naphthalene or anthracene with one or more hydrogen atoms removed, and most preferably a group from naphthalene with one or more hydrogen atoms removed. １４ A substituent that may be present is Ra １０４ Examples of substituents that may be present include those similar to those that the molecule may have.

[0084] Ra' in equation (a1-r2-4) １４ When is a naphthyl group, the position of bonding to the tertiary carbon atom in formula (a1-r2-4) may be either position 1 or position 2 of the naphthyl group. Ra' in formula (a1-r2-4) １４ If is an anthyl group, the position of bonding to the tertiary carbon atom in formula (a1-r2-4) may be position 1, 2, or 9 of the anthyl group.

[0085] Specific examples of the group represented by the above formula (a1-r2-1) are given below.

[0086]

[0087]

[0088]

[0089] Specific examples of the group represented by the above formula (a1-r2-2) are given below.

[0090]

[0091]

[0092]

[0093] Specific examples of the group represented by the above formula (a1-r2-3) are given below.

[0094]

[0095] Specific examples of the group represented by the above formula (a1-r2-4) are given below.

[0096]

[0097] Tertiary alkyloxycarbonylic acid dissociable group: Among the polar groups, an example of an acid-dissociable group that protects a hydroxyl group is the acid-dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as a "tertiary alkyloxycarbonylic acid dissociable group" for convenience).

[0098] [In the formula, Ra' ７ ~Ra' ９ These are each alkyl groups.

[0099] In formula (a1-r-3), Ra' ７ ~Ra' ９ Each alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Furthermore, the total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0100] Secondary alkyl ester type acid-dissociating groups: Among the polar groups mentioned above, an example of an acid-dissociating group that protects a carboxyl group is the acid-dissociating group represented by the following general formula (a1-r-4).

[0101] [In the formula, Ra' １０ Ra' is a hydrocarbon group. １１ａ and Ra' １１ｂ Each of these is independently a hydrogen atom, a halogen atom, or an alkyl group. Ra' １２ is a hydrogen atom or a hydrocarbon group. Ra' １０ and Ra' １１ａ Or Ra' １１ｂ These may be joined together to form a ring. １１ａ Or Ra' １１ｂ And, Ra' １２ These elements may be joined together to form a ring.

[0102] In the formula, Ra' １０ and Ra' １２The hydrocarbon group in this is the Ra' group. ３ Similar examples can be given. In the formula, Ra' １１ａ and Ra' １１ｂ The alkyl group in is the Ra' １ Examples include alkyl groups similar to those in the formula. In the formula, Ra' １０ and Ra' １２ The hydrocarbon group in, and Ra' １１ａ and Ra' １１ｂ The alkyl group in may have substituents. For example, the above-mentioned Ra ｘ５ These are some examples.

[0103] Ra' １０ and Ra' １１ａ Or Ra' １１ｂ These elements may bond to each other to form a ring. This ring may be polycyclic or monocyclic, and may be alicyclic or aromatic. The alicyclic and aromatic rings may contain heteroatoms.

[0104] Ra' １０ and Ra' １１ａ Or Ra' １１ｂ The rings formed by the bonding of these elements are preferably monocycloalkenes, rings in which some of the carbon atoms of a monocycloalken are substituted with heteroatoms (oxygen atoms, sulfur atoms, etc.), monocycloalkadienes, cycloalkenes having 3 to 6 carbon atoms, and cyclopentene or cyclohexene.

[0105] Ra' １０ and Ra' １１ａ Or Ra' １１ｂ The ring formed by the bonding of these elements may be a fused ring. Specific examples of such fused rings include indane.

[0106] Ra' １０ and Ra' １１ａ Or Ra' １１ｂ The ring formed by the bonding of these elements may have substituents. For example, the above-mentioned Ra ｘ５ These are some examples.

[0107] Ra' １１ａOr Ra' １１ｂ And, Ra' １２ These elements may be bonded together to form a ring, and the ring may be Ra' １０ and Ra' １１ａ Or Ra' １１ｂ Examples include rings formed by the bonding of these elements together.

[0108] Specific examples of the group represented by the above formula (a1-r-4) are given below.

[0109]

[0110] Rc ０１ , Rc ０２ , and Rc ０３ The acid-degradable group in this is preferably an acid-degradable group represented by any of the following general formulas (Rm-01) to (Rm-06).

[0111] [In formula (Rm-01), Rm １１ and Rm １２ Each of these is independently either a hydrogen atom or an alkyl group. １３ is a hydrocarbon group, Rm １３ is, Rm １１ and Rm １２ It may combine with any of the following to form a ring. ０１ Rm is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-02), Rm ２１ and Rm ２２ Each of these is independently either a hydrogen atom or an alkyl group. ２３ is a hydrocarbon group, Rm ２３ is, Rm ２１ and Rm ２２ It may combine with any of the following to form a ring. ０２Rm is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-03), Rm ３１ and Rm ３２ Each of these is independently either a methyl group or a hydrogen atom. ０３ Rm is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-04), Rm ４１ ~Rm ４３ Each is independently a hydrocarbon group, and Rm ４２ and Rm ４３ They may be joined to each other to form a ring. ０４ Rm is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-05), Rm ５１ Rm is a hydrocarbon group. ５３ and Rm ５４ Each of these is independently a hydrogen atom, a halogen atom, or an alkyl group. ５２ Rm is a hydrogen atom or a hydrocarbon group. ５１ and Rm ５３ or Rm ５４ These elements may be joined together to form a ring. Rm ５３ or Rm ５４ And, Rm ５２ These may be joined together to form a ring. ０５ Rm is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-06), Rm ６１ ~Rm６３ Each of these is an alkyl group, independently of the others. ０６ This is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. * is Ar in general formula (d0) ０１ Ar ０２ or Ar ０３ This shows the combination.

[0112] In the above general formulas (Rm-01) to (Rm-06), L ０１ ~L ０６ This is a divalent linking group selected from the group consisting of ester bonds (-C(=O)-O-), oxycarbonyl groups (-O-C(=O)-), ether bonds (-O-), -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof.

[0113] L ０１ ~L ０６ The number of carbon atoms in the linear and branched alkylene groups is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 5, and particularly preferably 1 to 3.

[0114] L ０１ ~L ０６ Among the above, a divalent linking group selected from the group consisting of an ester bond (-C(=O)-O-), an ether bond (-O-), a linear alkylene group, a branched alkylene group, and a group consisting of two or more combinations thereof is preferred, and a divalent linking group selected from the group consisting of an ether bond (-O-), a linear alkylene group, a branched alkylene group, and a group consisting of two or more combinations thereof is more preferred, *-O-Rl ０１ - (Rl ０１ A divalent linking group (which is a linear or branched alkylene group) is even more preferred.

[0115] In the above general formula (Rm-01), Rm １１ , Rm１２ and Rm １３ This is Ra' in the above general formula (a1-r-1). １ , Ra' ２ and Ra' ３ These are the same as above. In the general formula (Rm-02) above, Rm ２１ , Rm ２２ and Rm ２３ Also, Ra' in the above general formula (a1-r-1) １ , Ra' ２ and Ra' ３ These are the same as above.

[0116] In the above general formula (Rm-03), Rm ３１ and Rm ３２ These are, independently, a methyl group or a hydrogen atom.

[0117] The acid-degradable group represented by the general formula (Rm-04) is Rm ４１ ~Rm ４３ The acid-dissociable group formed by this process is preferably an acid-degradable group represented by the following general formula (Rm-04a) or (Rm-04b).

[0118] [In formula (Rm-04a), Ra ４１ This represents a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with halogen atoms or heteroatom-containing groups. ４２ Ra ４１ It is a group that forms an aliphatic cyclic group together with the bonded carbon atom. ０４ Rb is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. In formula (Rm-04b), Rb ４１ and Rb ４２ Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Rb ４３ This is a hydrocarbon group that may have substituents. Lb ０４This is a divalent linking group selected from the group consisting of ester bonds, oxycarbonyl groups, ether bonds, -C(=O)-NH-, -NH-C(=O)-, linear alkylene groups, branched alkylene groups, and groups consisting of two or more combinations thereof. * is Ar in general formula (d0) ０１ Ar ０２ or Ar ０３ This shows the combination.

[0119] In the above general formula (Rm-04a), Ra ４１ and Ra ４２ This is Ra' in the above general formula (a1-r2-1). １０ and Ra' １１ These are the same. La ０４ L in the above general formula (Rm-04) ０４ It is the same as this.

[0120] In the above general formula (Rm-04a), Ra ４１ Among the above, it is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, preferably a linear or branched alkyl group having 1 to 7 carbon atoms, preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and particularly preferably a linear or branched alkyl group having 1 to 3 carbon atoms.

[0121] In the above general formula (Rm-04a), Ra ４２ and Ra ４１ Among the above, monocyclic aliphatic hydrocarbon groups are preferred as aliphatic cyclic group formed together with the bonded carbon atom, and cyclopentyl groups and cyclohexyl groups are more preferred.

[0122] In the above general formula (Rm-04b), Rb ４１ , Rb ４２ and Rb ４３ This is Ra' in the above general formula (a1-r2-4). １２ , Ra' １３ and Ra' １４ These are the same as Lb. ０４ L in the above general formula (Rm-04) ０４ It is the same as this.

[0123] In the above general formula (Rm-04b), Rb ４１ , Rb ４２ and Rb ４３ Among the above, each is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, preferably a linear or branched alkyl group having 1 to 7 carbon atoms, preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and particularly preferably a linear or branched alkyl group having 1 to 3 carbon atoms.

[0124] In the above general formula (Rm-05), Rm ５１ , Rm ５２ , Rm ５３ and Rm ５４ This is Ra' in the above general formula (a1-r-4). １０ , Ra' １２ , Ra' １１ａ and Ra' １１ｂ These are similar in each case.

[0125] In the above general formula (Rm-06), Rm ６１ ~Rm ６３ This is Ra' in the above general formula (a1-r-3). ７ ~Ra' ９ These are the same as above.

[0126] Rc ０１ , Rc ０２ , and Rc ０３ Among the above, alkyl groups, groups represented by the general formula (ca-r-1) or (ca-r-8), electron-withdrawing groups other than cyano groups, or acid-degradable groups are preferred.

[0127] Rc ０１ , Rc ０２ , and Rc ０３ At least one of these is preferably an acid-degradable group from the viewpoint of improving sensitivity, LWR, and etching resistance. ０１ , Rc ０２ , and Rc ０３ From the viewpoint of improving sensitivity and etching resistance, at least one of these is preferably an electron-withdrawing group other than a cyano group.

[0128] In the general formula (a0-m), k01, k02, and k03 are each independently preferably integers from 0 to 3, more preferably integers from 0 to 2, and even more preferably 0 or 1. k01 + k02 + k03 are preferably integers from 0 to 9, more preferably integers from 1 to 6, and even more preferably integers from 2 to 5, as long as the valence allows.

[0129] In the general formula (a0-m), Z ０２ and Z ０３ If each of these is independently a substituent other than a cyano group or a hydrogen atom, the substituent other than a cyano group is the aforementioned Rc ０１ , Rc ０２ , and Rc ０３ Examples include substituents other than the cyano group in the above general formula (a0-m), Z ０２ and Z ０３ When these elements bond to each other to form a single bond or a divalent linking group, the divalent linking group is not particularly limited, but examples include a divalent hydrocarbon group which may have substituents, a divalent linking group which contains a heteroatom, etc.

[0130] - Divalent hydrocarbon groups which may have substituents: Divalent hydrocarbon groups which may have substituents may be aliphatic hydrocarbon groups or aromatic hydrocarbon groups.

[0131] ...Aliphatic hydrocarbon group An aliphatic hydrocarbon group means a hydrocarbon group that does not possess aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferred to be saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups that contain a ring in their structure.

[0132] ...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, even 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 preferred, specifically a methylene group [-CH ２ -], ethylene group [- (CH ２ ) ２-], trimethylene group [-(CH ２ ) ３ -], tetramethylene group [-(CH ２ ) ４ -], pentamethylene group [-(CH ２ ) ５ Examples include -]. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. A branched alkylene group is preferred as the branched aliphatic hydrocarbon group, specifically -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkyl methylene groups such as -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ -, -C(CH ２ CH ３ ) ２ -CH ２ - Alkyl ethylene groups such as -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH３ )CH ２ CH ２ Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0133] The linear or branched aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include fluorine atoms, fluorinated alkyl groups having 1 to 5 carbon atoms substituted with fluorine atoms, and carbonyl groups.

[0134] ...Aliphatic hydrocarbon groups containing a ring in their structure Examples of aliphatic hydrocarbon groups containing a ring in their structure include cyclic aliphatic hydrocarbon groups (groups obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), which may contain substituents containing heteroatoms in their ring structure; groups in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group; and groups in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group are the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferred. As a monocycloalkane, those having 3 to 6 carbon atoms are preferred, and specifically examples include cyclopentane and cyclohexane. As for the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferred, and as the polycycloalkane, those having 7 to 12 carbon atoms are preferred, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include decane and tetracyclododecane.

[0135] The cyclic aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and carbonyl groups. Preferably, the alkyl group is a C1-C5 alkyl group, more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Preferably, the alkoxy group is a C1-C5 alkoxy group, more preferably a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, or tert-butoxy group, and even more preferably a methoxy group or ethoxy group. Preferably, the halogen atom is a fluorine atom. Examples of alkyl halides are groups in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. The cyclic aliphatic hydrocarbon group may also have some of the carbon atoms constituting its ring structure substituted with substituents containing heteroatoms. Substituents containing the heteroatom include -O-, -C(=O)-O-, -S-, and -S(=O). ２ -, -S (=O) ２ -O- is preferred.

[0136] ...Aromatic hydrocarbon group The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. Specific examples of aromatic hydrocarbon groups include: a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) in which one hydrogen atom is replaced by an alkylene group (e.g., a group obtained by removing one more hydrogen atom from the aryl group in an arylalkyl group such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0137] The aromatic hydrocarbon group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, and hydroxyl groups. The alkyl group substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Examples of the alkoxy group, halogen atom, and alkyl halide substituent are those exemplified as substituents that substitute for hydrogen atoms in the cyclic aliphatic hydrocarbon group.

[0138] • Divalent linking groups containing heteroatoms: Examples of divalent linking groups containing heteroatoms include -O-, -C(=O)-O-, -O-C(=O)-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with substituents such as alkyl groups or acyl groups), -S-, -S(=O) ２ -, -S (=O) ２ -O-, general 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 -OC(=O)-Y ２２ - or - Y ２１ -S (=O) ２ -O-Y ２２ - is represented by the base [wherein Y ２１ and Y ２２Each of these is a divalent hydrocarbon group which may independently have substituents, O is an oxygen atom, and m'' is an integer from 1 to 3. For example, when the divalent linking group containing the heteroatom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)-, the H may be substituted with substituents such as alkyl groups or acyl groups. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5. General formula -Y ２１ -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 -OC(=O)-Y ２２ - or - Y ２１ -S (=O) ２ -O-Y ２２ - Middle, Y ２１ and Y ２２ Each of these is independently a divalent hydrocarbon group which may have substituents. Examples of such divalent hydrocarbon groups are those described above. ２１ Preferably, a linear aliphatic hydrocarbon group is preferred, a linear alkylene group is more preferred, a linear alkylene group having 1 to 5 carbon atoms is even more preferred, and a methylene group or ethylene group is particularly preferred. ２２ Preferably, the group is a linear or branched aliphatic hydrocarbon group, 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. Formula - [Y ２１ -C (=O) -O] ｍ” -Y ２２ In the base represented by -, m'' is an integer from 1 to 3, preferably 1 or 2, and more preferably 1. That is, formula -[Y ２１ -C (=O) -O] ｍ”-Y ２２ As a base represented by -, see formula -Y ２１ -C(=O)-O-Y ２２ Groups represented by - are particularly preferred. Among them, the group represented by formula -(CH ２ ) ａ’ -C(=O)-O-(CH ２ ) ｂ’ A base represented by - is preferred. In the formula, a' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, even more preferably 1 or 2, and most preferably 1. b' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, even more preferably 1 or 2, and most preferably 1.

[0139] Z ０２ and Z ０３ When these bonds combine to form a single bond or a divalent linking group, they are called single bonds, ester bonds [-C(=O)-O-, -O-C(=O)-], ether bonds (-O-), -C(=O)-, and -S(=O). ２ - Linear or branched alkylene groups, or combinations thereof, are preferred, and single bonds are more preferred.

[0140] Z ０２ and Z ０３ From the viewpoint of further reducing roughness, it is preferable that each of these substituents be a substituent other than a cyano group or a hydrogen atom, with hydrogen atoms being more preferable.

[0141] The cation portion of the constituent unit (a0) is preferably a cation represented by the following general formula (a0-ca-1).

[0142] [In the formula, m011 represents an integer from 0 to 5, as far as the valence allows, and m012 and m013 each independently represent an integer from 0 to 4, as far as the valence allows, and m011 + m012 + m013 ≥ 1. Rc ０１１ , Rc ０１２ , and Rc ０１３These are, independently, electron-withdrawing groups other than cyano groups, alkyl groups, amino groups, and groups represented by the general formulas (ca-r-1) to (ca-r-8), respectively. k011 represents an integer from 0 to 5, as long as the valency allows. If k011 is an integer of 2 or more, then Rc is 2 or more. ０１１ k012 and k013 may be the same or different. k012 and k013 each independently represent integers from 0 to 4, as far as the valence allows. If k012 is an integer of 2 or more, then Rc must be 2 or more. ０１２ They may be the same or different from each other. If k013 is an integer of 2 or more, then Rc must be 2 or more. ０１３ They may be the same or different. (RPGD) ０１１ , Rpgd ０１２ and Rpgd ０１３ Each of these is an acid-degradable group. j011 represents an integer from 0 to 5, as far as the valency allows. j012 and j013 each independently represent an integer from 0 to 4, as far as the valency allows. If j011 is an integer of 2 or more, then Rpgd is 2 or more. ０１１ They may be the same or different from each other. If j012 is an integer of 2 or more, then Rpgd must be 2 or more. ０１２ They may be the same or different from each other. If j013 is an integer of 2 or more, then Rpgd must be 2 or more. ０１３ They may be the same or different from each other. Z ０１２ and Z ０１３ Each of these independently represents a substituent other than a cyano group, a cyano group, or a hydrogen atom, or Z ０１２ and Z ０１３ These groups bond to each other, forming single or divalent linking groups. m011 + k011 + j011 ≤ 5, m012 + k012 + j012 ≤ 4, and m013 + k013 + j013 ≤ 4.

[0143] In the above formula (a0 - ca - 1), m011, m012, and m013 are preferably integers from 0 to 3, more preferably integers from 0 to 2, and even more preferably 0 or 1. m011 + m012 + m013 is preferably 1 or 2, and more preferably 2.

[0144] In the above formula (a0 - ca - 1), Rc ０１１ , Rc０１２ , and Rc ０１３ In the above formula (a0-m), electron-withdrawing groups other than cyano groups, alkyl groups, amino groups, and groups represented by the general formulas (ca-r-1) to (ca-r-8) are Rc ０１ , Rc ０２ , and Rc ０３ Examples similar to those described above can be given. Preferred examples are also similar. Rc ０１１ , Rc ０１２ , and Rc ０１３ In this context, alkyl groups having 1 to 3 carbon atoms are preferred, and methyl groups are more preferred. ０１１ , Rc ０１２ , and Rc ０１３ In this compound, electron-withdrawing groups other than cyano groups are preferably halogen atoms or alkyl halides, with iodine atoms preferred from the viewpoint of improving sensitivity and fluorine atoms preferred from the viewpoint of maintaining LWR. Trifluoromethyl groups are preferred as alkyl halides. ０１１ , Rc ０１２ , and Rc ０１３ In the above general formulas (ca-r-1) to (ca-r-8), the group represented by formula (ca-r-1) or (ca-r-8) is preferred, a hydroxyl group, a methyl group, or a methoxy group is more preferred, and a methyl group or a methoxy group is even more preferred.

[0145] Rc ０１１ , Rc ０１２ , and Rc ０１３ Preferably, the group is an alkyl group, a group represented by the general formula (ca-r-1) or (ca-r-8), or an electron-withdrawing group other than a cyano group. ０１１ , Rc ０１２ , and Rc ０１３ At least one of these is preferably an electron-withdrawing group other than a cyano group. ０１１ , Rc ０１２ , and Rc ０１３ Preferably, at least one of these atoms is a fluorine atom or an iodine atom.

[0146] In the above formula (a0 - ca - 1), k011, k012, and k013 are each independently preferably integers from 0 to 3, more preferably 1 or 2. k011 + k012 + k013 are preferably integers from 0 to 9, more preferably integers from 1 to 6, and even more preferably integers from 2 to 4.

[0147] In the above formula (a0 - ca - 1), Rpgd ０１１ , Rpgd ０１２ , and Rpgd ０１３ Rc in the above formula (a0-m) ０１ , Rc ０２ , and Rc ０３ Examples include those similar to the acid-degradable groups in [the relevant context]. In particular, Rpgd ０１１ , Rpgd ０１２ , and Rpgd ０１３ As such, an acid-degradable group represented by the formula (Rm-04) is preferred. In particular, an acid-degradable group containing an acid-dissociable group represented by the formula (Rm-04a) or (Rm-04b) is preferred.

[0148] In the above formula (a0 - ca - 1), j011, j012, and j013 are preferably integers from 0 to 3, more preferably integers from 0 to 2, and even more preferably 0 or 1. j011 + j012 + j013 are preferably integers of 1 or more, and from the viewpoint of improving sensitivity, LWR, and etching resistance, integers of 2 or more are preferred, and even more preferably 2.

[0149] In the above formula (a0 - ca - 1), Z ０１２ and Z ０１３ The substituents other than the cyano group in formula (a0-m) are Rc ０１ , Rc ０２ , and Rc ０３ Examples of substituents other than the cyano group in Z include those similar to those in Z. ０１２ and Z ０１３ The divalent linking group formed by the mutual bonding of these elements is Z in formula (a0-m). ０２ and Z ０３ Examples of divalent linking groups formed by the mutual bonding of these elements are similar to those listed above. ０１２ and Z ０１３ It is preferable that these are hydrogen atoms or are bonded to each other to form a single bond.

[0150] The cation portion of the constituent unit (a0) is preferably a cation represented by the following general formula (a0-ca-1a) or (a0-ca-1b).

[0151] [In the formula, m011 represents an integer from 0 to 5, as far as the valence allows, and m012 and m013 each independently represent an integer from 0 to 4, as far as the valence allows, and m011 + m012 + m013 ≥ 1. Rc ０１１ , Rc ０１２ , and Rc ０１３ These are, independently, electron-withdrawing groups other than cyano groups, alkyl groups, amino groups, and groups represented by the general formulas (ca-r-1) to (ca-r-8), respectively. k011 represents an integer from 0 to 5, as long as the valency allows. If k011 is an integer of 2 or more, then Rc is 2 or more. ０１１ k012 and k013 may be the same or different. k012 and k013 each independently represent integers from 0 to 4, as far as the valence allows. If k012 is an integer of 2 or more, then Rc must be 2 or more. ０１２ They may be the same or different from each other. If k013 is an integer of 2 or more, then Rc must be 2 or more. ０１３ They may be the same or different. (RPGD) ０１１ , Rpgd ０１２ and Rpgd ０１３ Each of these is an acid-degradable group. j011 represents an integer from 0 to 5, as far as the valency allows. j012 and j013 each independently represent an integer from 0 to 4, as far as the valency allows. If j011 is an integer of 2 or more, then Rpgd is 2 or more. ０１１ They may be the same or different from each other. If j012 is an integer of 2 or more, then Rpgd must be 2 or more. ０１２ They may be the same or different from each other. If j013 is an integer of 2 or more, then Rpgd must be 2 or more. ０１３ They may be the same or different. ０１１These form single or divalent linking groups. m011 + k011 + j011 ≤ 5, m012 + k012 + j012 ≤ 4, and m013 + k013 + j013 ≤ 4. m021, m022, and m023 each independently represent integers from 0 to 5, as far as their valence allows, and m021 + m022 + m023 ≥ 1. k021, k022, and k023 each independently represent integers from 0 to 5, as far as their valence allows. j021, j022, and j023 each independently represent integers from 0 to 5, as far as their valence allows. m021 + k021 + j021 ≤ 5, m022 + k022 + j022 ≤ 5, and m023 + k023 + j023 ≤ 5.

[0152] Rc in the above formula (a0-ca-1a) or (a0-ca-1b) ０１１ , Rc ０１２ , Rc ０１３ , Rpgd ０１１ , Rpgd ０１２ and Rpgd ０１３ Rc in the above formula (a0 - ca - 1) ０１１ , Rc ０１２ , Rc ０１３ , Rpgd ０１１ , Rpgd ０１２ and Rpgd ０１３ These are the same as the above. The m011, m012, m013, k011, k012, k013, j011, j012, and j013 in the above formula (a0-ca-1a) are the same as the m011, m012, m013, k011, k012, k013, j011, j012, and j013 in the above formula (a0-ca-1).

[0153] In the above formula (a0 - ca - 1b), m021, m022, and m023 are preferably integers from 0 to 3, more preferably integers from 0 to 2, and even more preferably 0 or 1. m021 + m022 + m023 is preferably 1 or 2, and more preferably 2.

[0154] In the above formula (a0 - ca - 1b), k021, k022, and k023 are each independently preferably integers from 0 to 3, more preferably 1 or 2. k021 + k022 + k023 are preferably integers from 0 to 9, more preferably integers from 1 to 6, and even more preferably integers from 2 to 4.

[0155] In the above formula (a0 - ca - 1b), j021, j022, and j023 are preferably integers from 0 to 3, more preferably integers from 0 to 2, and even more preferably 0 or 1. j021 + j022 + j023 are preferably integers of 1 or more, and from the viewpoint of improving sensitivity, LWR, and etching resistance, integers of 2 or more are preferred, and even more preferably 2.

[0156] In the above formula (a0 - ca - 1b), Y ０１１ The divalent linking group in the above formula (a0-ca) is Z ０２ and Z ０３ Examples of divalent linking groups formed by the mutual bonding of these elements are similar to those listed above. ０１１ The divalent linking groups in are preferably alkylene groups having 1 to 3 carbon atoms, carbonyl groups, oxygen atoms, -C(=O)-O-, and -O-C(=O)-. The alkylene group having 1 to 3 carbon atoms is preferably a methylene group or an ethylene group, with the methylene group being more preferred.

[0157] The following are specific examples of the cation moiety of compounds represented by the general formula (a0-m), but are not limited to these.

[0158]

[0159]

[0160] {Anion part} In the above general formula (a0-m), W ０In the context of polymerizable group-containing groups, "polymerizable group" refers to a group that enables a polymerizable compound to be polymerized by radical polymerization or the like, and includes, for example, a group containing multiple bonds between carbon atoms, such as an ethylenic double bond. Examples of polymerizable groups include vinyl group, allyl group, acryloyl group, methacryloyl group, fluorovinyl group, difluorovinyl group, trifluorovinyl group, difluorotrifluoromethylvinyl group, trifluoroallyl group, perfluoroallyl group, trifluoromethylacryloyl group, nonylfluorobutylacryloyl group, vinyl ether group, fluorine-containing vinyl ether group, allyl ether group, fluorine-containing allyl ether group, styryl group, vinylnaphthyl group, fluorine-containing styryl group, fluorine-containing vinylnaphthyl group, norbornyl group, fluorine-containing norbornyl group, and silyl group. Among these, vinyl group is preferred as the polymerizable group.

[0161] A polymerizable group-containing group may be a group composed solely of a polymerizable group, or a group composed of a polymerizable group and other groups other than the polymerizable group. Examples of other groups other than the polymerizable group include divalent hydrocarbon groups which may have substituents, and divalent linking groups containing heteroatoms. An example of a polymerizable group-containing group is a group of formula: C(R Ｘ１１ ) (Caution Ｘ１２ ) = C(R Ｘ１３ )-Ya ｘ０ A group represented by - is preferably mentioned. In the above formula, R Ｘ１１ , R Ｘ１２ and R Ｘ１３ Each of these independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogenated group having 1 to 5 carbon atoms, and Ya ｘ０ This represents a single bond or a divalent linking group. ｘ０ The divalent linking group in is not particularly limited, but in the general formula (a0-m), Z ０２ and Z ０３ Examples include the same divalent linking groups as in [the given example].

[0162] In the above general formula (a0-m), Ya ｘ０Preferred members include single bonds, ester bonds [-C(=O)-O-, -O-C(=O)-], ether bonds (-O-), linear or branched alkylene groups, or combinations thereof, with single bonds and ester bonds [-C(=O)-O-, -O-C(=O)-] being more preferred.

[0163] W in the above formula (a0-m) ０ It is preferable that the polymerizable group-containing group is represented by the following general formula (a0-w).

[0164] [In the formula, R ０ This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, or a hydrogen atom. -L １０ -* represents -C(=O)-O-*, -C(=O)-NH-*, or -*(L １０ (This is the case when it is a single bond). * is R in the general formula (a0-m) above. Ａｒ１ This indicates a bonding operation.

[0165] R in the above formula (a0 - w) ０ The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. ０ The C1-C5 alkyl halide in this expression is a group in which some or all of the hydrogen atoms of the C1-C5 alkyl group are substituted with halogen atoms. Fluorine atoms are particularly preferred as the halogen atoms. ０ Examples include hydrogen atoms, alkyl groups having 1 to 5 carbon atoms, or fluorinated alkyl groups having 1 to 5 carbon atoms. Due to their industrial availability, hydrogen atoms, methyl groups, or trifluoromethyl groups are preferred, hydrogen atoms or methyl groups are more preferred, and hydrogen atoms are even more preferred.

[0166] In the above general formula (a0-m), Y ０ The divalent linking group in is not particularly limited, but in the general formula (a0-m), Z ０２ and Z ０３Examples include the same divalent linking groups as in [the given example].

[0167] A good example of the anionic moiety of compound (a0-m) is the anionic moiety represented by the following general formula (a0-an1).

[0168] [In the formula, R １０ａ This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La １０ａ This is a divalent linking group or a single bond. Ra １０ａ n is a divalent hydrocarbon group which may have substituents. １０ａ It is an integer between 0 and 2. １１ａ It is a divalent linking group. １０ａ Rf is a divalent linking group or a single bond. １０ａ It is a divalent linking group containing a fluorine atom.

[0169] In the above general formula (a0-an1), R １０ａ The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. １０ａ In this context, a halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. １０ａ Examples of halogen atoms in this compound include fluorine, chlorine, bromine, and iodine atoms. In alkyl halides, fluorine is particularly preferred as the halogen atom. １０ａ Preferably, the group is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms; more preferably, a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms; and even more preferably, a hydrogen atom or a methyl group due to their industrial availability.

[0170] In the above general formula (a0-an1), La １０ａIn the above general formula (a0-m), the divalent linking group is Z ０２ and Z ０３ Examples include the same divalent linking groups as in the above. １０ａ Preferably, the bonds are ester bonds [-C(=O)-O-, -O-C(=O)-], ether bonds (-O-), linear or branched alkylene groups, aromatic hydrocarbon groups or combinations thereof, or single bonds. Among these, La １０ａ More preferably, the components are ester bonds [-C(=O)-O-, -O-C(=O)-], aromatic hydrocarbon groups, or combinations thereof.

[0171] In the above general formula (a0-an1), Ra １０ａ A divalent hydrocarbon group which may have substituents in the above general formula (a0-m) is Z ０２ and Z ０３ Examples include divalent hydrocarbon groups that may have substituents, such as Ra. １０ａ Preferably, the group is an aliphatic hydrocarbon group containing a ring in its structure; more preferably, a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure; even more preferably, a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents; particularly preferably, a group obtained by removing two hydrogen atoms from a polycycloalkane; and most preferably, a group obtained by removing two hydrogen atoms from adamantane. Alternatively, Ra １０ａ Preferably, the substituent is an aromatic hydrocarbon group which may have substituents; preferably, an aromatic hydrocarbon ring which may have substituents or an aromatic heterocycle from which two hydrogen atoms have been removed (arylene group or heteroarylene group); more preferably, an arylene group which may have substituents; and even more preferably, a phenylene group which may have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, etc., with halogen atoms being preferred and iodine atoms being more preferred.

[0172] n １０ａ If it is 2, then two Ra １０ａThese may all be alicyclic hydrocarbon groups which may have substituents, or they may all be aromatic hydrocarbon groups which may have substituents, or they may be a combination of alicyclic hydrocarbon groups which may have substituents and aromatic hydrocarbon groups which may have substituents. １０ａ If it is 2, then two Ra １０ａ They may be the same or they may be different.

[0173] In the above general formula (a0-an1), La １１ａ In the above (a0-m), Z is a divalent linking group. ０２ and Z ０３ Examples include divalent linking groups similar to those in [the relevant context].

[0174] La １１ａ Preferably, the aliphatic hydrocarbon group is an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents. Alternatively, La １１ａ Preferably, the substituent is an aromatic hydrocarbon group which may have substituents, more preferably an aromatic hydrocarbon ring which may have substituents or an aromatic heterocycle from which two hydrogen atoms have been removed (arylene group or heteroarylene group), even more preferably an arylene group which may have substituents, and particularly preferably an phenylene group which may have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, etc., with halogen atoms being preferred and iodine atoms being more preferred. Alternatively, La １１ａ It is preferable that it contains an ester bond or an ether bond, and more preferably an ester bond. １１ａ n １０ａ When is 0, it is preferable to include an arylene group which may have substituents and an ester bond or an ether bond, more preferably an phenylene group which may have substituents and an ester bond, even more preferably a phenylene group and an ester bond, and particularly preferably a phenylene group and an ester bond. １１ａ n １０ａWhen the value is 1 or 2, it is preferably an ester bond.

[0175] In the above general formula (a0-an1), Ya １０ａ In the above general formula (a0-m), the divalent linking group is Z ０２ and Z ０３ This is similar to the divalent linking group in the above. １０ａ In this, the divalent linking group is preferably an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents. Alternatively, Ya １０ａ The divalent linking group in is preferably an aromatic hydrocarbon group which may have substituents, more preferably an aromatic hydrocarbon ring which may have substituents or an aromatic heterocycle from which two hydrogen atoms have been removed (arylene group or heteroarylene group), even more preferably an arylene group which may have substituents, and particularly preferably an phenylene group which may have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, etc., with halogen atoms being preferred and iodine atoms being more preferred. Alternatively, Ya １０ａ The divalent linking group in this compound preferably includes an ester bond or an ether bond, with an ester bond being more preferred. １０ａ n １０ａ When is 0, it is preferable to include an arylene group which may have substituents and an ester bond or an ether bond, more preferably an phenylene group which may have substituents and an ester bond, even more preferably a phenylene group which may have a halogen atom and an ester bond, and particularly preferably a phenylene group which may have an iodine atom and an ester bond. １０ａ n １０ａ When the number is 1 or 2, a single bond is preferred.

[0176] In the above general formula (a0-an1), Rf １０ａThe divalent linking group in is not particularly limited except that it has a fluorine atom, but in the general formula (a0-m), Z ０２ and Z ０３ This is similar to the divalent linking group in Rf. １０ａ It may have a fluorinated phenylene group or a fluorinated alkylene group. Among the above, Rf １０ａ From the perspective of acid strength, SO ３－ It is preferable that at least one fluorine atom or a fluorinated alkyl group having at least one fluorine atom is bonded to the carbon atom adjacent to the carbon atom, and it is more preferable that two fluorine atoms are bonded to the carbon atom.

[0177] Alternatively, a good example of the anionic moiety of compound (a0-m) is the anionic moiety represented by the following general formula (a0-an2).

[0178] [In the formula, R ２０ａ and R ２１ａ Each of these is independently an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La ２０ａ This is a divalent linking group or a single bond. ２０ａ Rf is a divalent linking group. ２０ａ It is a divalent linking group containing a fluorine atom.

[0179] In the above general formula (a0-an2), R ２０ａ and R ２１ａ In the above general formula (a0-an1), R is an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms. １０ａ Examples include alkyl groups having 1 to 5 carbon atoms and halogenated alkyl groups having 1 to 5 carbon atoms. In the general formula (a0-an2), R ２０ａ and R ２１ａ Due to their industrial availability, methyl groups or hydrogen atoms are more preferred, and hydrogen atoms are even more preferred.

[0180] In the above general formula (a0-an2), La ２０ａIn the above formula (a0-an1), the divalent linking group is La １１ａ Examples include divalent linking groups similar to those in the above. ２０ａ In this, the divalent linking group is preferably an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents. Alternatively, La ２０ａ The divalent linking group in is preferably an optionally substituted aromatic hydrocarbon group, more preferably an optionally substituted aromatic hydrocarbon ring or aromatic heterocycle from which two hydrogen atoms have been removed (arylene group or heteroarylene group), even more preferably an optionally substituted arylene group, and particularly preferably an optionally substituted phenylene group. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, etc., with halogen atoms being preferred and iodine atoms being more preferred. Alternatively, La ２０ａ The divalent linking group in this is preferably an ester bond or an ether bond, with an ester bond being more preferable. ２０ａ The components preferably include an arylene group which may have a substituent and an ester bond or an ether bond, or a single bond; more preferably include an phenylene group which may have a substituent and an ester bond, an ester bond or a single bond; even more preferably include a phenylene group and an ester bond, an ester bond or a single bond; and particularly preferably a single bond.

[0181] In the above general formula (a0-an2), Ya ２０ａ In the above general formula (a0-m), the divalent linking group is Z ０２ and Z ０３ This is similar to the divalent linking group in the above. ２０ａIn this, the divalent linking group is preferably an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents. Alternatively, Ya ２０ａ Preferably, the substituent is an aromatic hydrocarbon group which may have substituents, more preferably an aromatic hydrocarbon ring which may have substituents or an aromatic heterocycle from which two hydrogen atoms have been removed (arylene group or heteroarylene group), even more preferably an arylene group which may have substituents, and particularly preferably an phenylene group which may have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, etc., with halogen atoms being preferred and iodine atoms being more preferred. Alternatively, Ya ２０ａ It is preferable that it contains an ester bond or an ether bond, and more preferably an ester bond. ２０ａ Preferably, the material comprises an arylene group which may have a substituent and an ester bond or an ether bond; more preferably, a phenylene group which may have a substituent and an ester bond; even more preferably, a phenylene group which may have a halogen atom and an ester bond; and particularly preferably, a phenylene group which may have an iodine atom and an ester bond.

[0182] In the above general formula (a0-an2), Rf ２０ａ In the above formula (a0-an1), the divalent linking group having a fluorine atom is Rf １０ａ Examples include divalent linking groups having a fluorine atom, such as Rf. ２０ａ It may have a fluorinated phenylene group or a fluorinated alkylene group. Among the above, Rf ２０ａ From the perspective of acid strength, SO ３－ It is preferable that at least one fluorine atom or a fluorinated alkyl group having at least one fluorine atom is bonded to the carbon atom adjacent to the carbon atom, and it is more preferable that two fluorine atoms are bonded to the carbon atom.

[0183] The following are specific examples of the anionic moieties of compounds represented by the general formula (a0-m), but are not limited to these. In the following formulas, R 10α , R ２0α , R ２１α This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom.

[0184]

[0185] Good examples of compounds represented by the general formula (a0-m) include the compound represented by the following general formula (a0-m1) or the compound represented by the following general formula (a0-m2). [In the formula, Ar ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ k01, k02, and k03 are, respectively, Ar in the general formula (a0-m). ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ , is identical to k01, k02, and k03. R １０ａ La １０ａ Ra １０ａ , n １０ａ La １１ａ Ya １０ａ , Rf １０ａ These are R in the general formula (a0-an1), respectively. １０ａ La １０ａ Ra １０ａ , n １０ａ La １１ａ Ya １０ａ , Rf １０ａ It is identical to [this].

[0186] [In the formula, Ar ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３k01, k02, and k03 are, respectively, Ar in the general formula (a0-m). ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ , is identical to k01, k02, and k03. R ２０ａ , R ２１ａ La ２０ａ Ya ２０ａ , Rf ２０ａ These are R in the general formula (a0-an1), respectively. ２０ａ , R ２１ａ La ２０ａ Ya ２０ａ , Rf ２０ａ It is identical to [this].

[0187] The following are specific examples of compounds represented by the general formula (a0-m), but are not limited to these.

[0188]

[0189]

[0190]

[0191]

[0192] The compound represented by the general formula (a0-m) is preferably selected from the group consisting of compounds represented by the formulas (a0-m-1) to (a0-m-36).

[0193] Alternatively, since sensitivity is more easily improved, it is preferably selected from the group consisting of compounds represented by the formulas (a0-m-3), (a0-m-8), (a0-m-12), (a0-m-14), (a0-m-18), (a0-m-19), (a0-m-21), (a0-m-22), (a0-m-24), (a0-m-26), and (a0-m-30) to (a0-m-36). More preferably, it is selected from the group consisting of compounds represented by the formulas (a0-m-8), (a0-m-12), (a0-m-18), (a0-m-19), (a0-m-21), (a0-m-22), and (a0-m-30) to (a0-m-36).

[0194] Alternatively, since roughness is more easily reduced, it is preferably selected from the group consisting of compounds represented by formulas (a0-m-1), (a0-m-2), (a0-m-4), (a0-m-5), (a0-m-7), (a0-m-9) to (a0-m-11), (a0-m-13), and (a0-m-15) to (a0-m-36). More preferably, it is selected from the group consisting of compounds represented by formulas (a0-m-15) to (a0-m-34). Even more preferably, it is selected from the group consisting of compounds represented by formulas (a0-m-15) to (a0-m-23), (a0-m-25), and (a0-m-27) to (a0-m-36).

[0195] Alternatively, because etching resistance is more easily improved, the compounds are preferably selected from the group consisting of compounds represented by formulas (a0-m-3), (a0-m-9), (a0-m-13), (a0-m-15) to (a0-m-31), (a0-m-34), and (a0-m-36). More preferably, the compounds are selected from the group consisting of compounds represented by formulas (a0-m-18) to (a0-m-30), (a0-m-34), and (a0-m-36).

[0196] Alternatively, from the viewpoint of achieving both high sensitivity, reduced roughness, and improved etching resistance, it is preferably selected from the group consisting of compounds represented by formulas (a0-m-3), (a0-m-8), (a0-m-9), (a0-m-12) to (a0-m-36). More preferably, it is selected from the group consisting of compounds represented by formulas (a0-m-15) to (a0-m-36). Even more preferably, it is selected from the group consisting of compounds represented by formulas (a0-m-18), (a0-m-19), (a0-m-21), (a0-m-22), (a0-m-24), (a0-m-26), (a0-m-30), (a0-m-31), (a0-m-34), and (a0-m-36).

[0197] (A1) The constituent units (a0) in the component may be one type or two or more types.

[0198] The proportion of constituent units (a0) in component (A1) is preferably 0.5 to 60 mol%, more preferably 1 to 40 mol%, even more preferably 5 to 30 mol%, and particularly preferably 10 to 20 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). By setting the proportion of constituent units (a0) to be above the lower limit of the above preferred range, sensitivity, roughness, and etching resistance are all good. On the other hand, if it is below the upper limit of the above preferred range, a balance with other constituent units can be achieved, and various lithography characteristics are good.

[0199] <<Other Constituent Units>> Component (A1) may have other constituent units as needed, in addition to the constituent unit (a0) described above. Examples of other constituent units include the constituent unit (a1) described below; the constituent unit (a10) represented by the general formula (a10-1) described below; the constituent unit (a2) containing a lactone-containing cyclic group; the constituent unit (a5) that generates acid upon exposure; the constituent unit (a6) that has acid diffusion controllability; and the constituent unit (a8) derived from the compound represented by the general formula (a8-1) described below.

[0200] Constituent unit (a1): Constituent unit (a1) is a constituent unit that contains an acid-degradable group whose polarity increases upon the action of an acid. As the acid-degradable group, in the general formula (a0-m) above, Rc ０１ , Rc ０２ , and Rc ０３ Examples include those similar to the acid-degradable groups in [the relevant context].

[0201] Examples of the constituent unit (a1) include a constituent unit derived from an acrylic acid ester in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent, a constituent unit derived from acrylamide, a constituent unit derived from hydroxystyrene or a hydroxystyrene derivative in which at least a portion of the hydrogen atoms in the hydroxyl group of the constituent unit is protected by a substituent containing the acid-degradable group, and a constituent unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative in which at least a portion of the hydrogen atoms in the -C(=O)-OH group is protected by a substituent containing the acid-degradable group.

[0202] As for the constituent unit (a1), among the above, a constituent unit derived from an acrylic acid ester in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent is preferred. Preferred specific examples of such constituent unit (a1) include the constituent units represented by the following general formulas (a1-1), (a1-2), or (a1-3).

[0203] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogenated group having 1 to 5 carbon atoms. Va １ n is a divalent hydrocarbon group which may have an ether bond. ａ１ is an integer between 0 and 2. １ This is an acid-dissociable group represented by the general formula (a1-r-1), (a1-r-2), or (a1-r-4) above. Wa １ han ａ２ It is a +1 valent hydrocarbon group. ａ２ Ra is an integer between 1 and 3. ２ This is an acid-dissociable group represented by the general formula (a1-r-1) or (a1-r-3) above. ００１ It is a single bond or a divalent linking group.０１ It is a single bond or a divalent linking group. Rax ０１ Rz is an acid-dissociable group represented by the general formula (a1-r-1), (a1-r-2), or (a1-r-4) above. ０１ [where n is an alkyl group, halogen atom, alkyl halide, hydroxyl group, or alkoxy group; q is an integer between 0 and 3; n is a non-negative integer, where n ≤ q × 2 + 4]

[0204] In formulas (a1-1) to (a1-3), the C1-C5 alkyl group of R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically including methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups. The C1-C5 halogenated alkyl group is a group in which some or all of the hydrogen atoms of the C1-C5 alkyl group are substituted with halogen atoms. Fluorine atoms are particularly preferred as the halogen atoms. R is preferably a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 fluorinated alkyl group, with hydrogen atoms or methyl groups being the most preferred due to their industrial availability.

[0205] In the above formula (a1-1), Va １ The divalent hydrocarbon group in this expression may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0206] Va １ The aliphatic hydrocarbon group as the divalent hydrocarbon group in this product may be saturated or unsaturated, but is usually preferred to be saturated. More specifically, examples of such aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups containing a ring in their structure.

[0207] The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. A linear alkylene group is preferred as the linear aliphatic hydrocarbon group, specifically a methylene group [-CH]２ -], ethylene group [- (CH ２ ) ２ -], trimethylene group [-(CH ２ ) ３ -], tetramethylene group [-(CH ２ ) ４ -], pentamethylene group [-(CH ２ ) ５ Examples include -]. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. A branched alkylene group is preferred as the branched aliphatic hydrocarbon group, specifically -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkyl methylene groups such as -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ -, -C(CH ２ CH ３ ) ２ -CH ２ - Alkyl ethylene groups such as -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as -CH(CH ３ )CH ２CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２ Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0208] Examples of aliphatic hydrocarbon groups containing a ring in the structure include alicyclic hydrocarbon groups (groups obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups 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 or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically examples include cyclopentane and cyclohexane. As for the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include decane and tetracyclododecane.

[0209] Va １In this context, the aromatic hydrocarbon group as a divalent hydrocarbon group is a hydrocarbon group having an aromatic ring. Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings in an aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in an aromatic heterocycle include oxygen atoms, sulfur atoms, and nitrogen atoms. Specifically, examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); and a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group) in which one hydrogen atom is replaced by an alkylene group (for example, a group obtained by removing one more hydrogen atom from the aryl group in an arylalkyl group such as a benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group (alkyl chain in an arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0210] In the above formula (a1-1), Ra １ The acid-dissociable group is preferably represented by the general formula (a1-r-2) or (a1-r-4) described above, and among these, the group represented by the general formula (a1-r2-1) or the acid-dissociable group represented by the general formula (a1-r-4) is more preferred.

[0211] In the above formula (a1-2), Wa １ n in ａ２The +1 valent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity, and may be saturated or unsaturated, but is usually preferred to be saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, or a group that is a combination of a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in its structure. ａ２ The +1 valency is preferably 2 to 4 valencies, and more preferably 2 or 3 valencies. In the above formula (a1-2), Ra ２ The acid-dissociable group represented by the general formula (a1-r-1) above is preferred.

[0212] In the above formula (a1-3), Ya ００１ The divalent linking group in this is not particularly limited, but suitable examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. ００１ Preferably, the alkylene group is an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, an aromatic hydrocarbon group or a combination thereof, or a single bond. The number of carbon atoms in the alkylene group is preferably 1 to 10, more preferably 1 to 6, even more preferably 1 to 4, and particularly preferably 1 to 3. Among these, Ya ００１ The combination of an ester bond [-C(=O)-O-, -O-C(=O)-] and a linear alkylene group is more preferable, and a single bond is even more preferable.

[0213] In the above formula (a1-3), Ya ０１ The divalent linking group in this is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have substituents, a divalent linking group which contains a heteroatom, and so on. ０１Among the above, it is preferable that the ester bond [-C(=O)-O-, -O-C(=O)-], ether bond (-O-), linear or branched alkylene group, aromatic hydrocarbon group or a combination thereof, or single bond. Among these, Ya ０１ The combination of an ester bond [-C(=O)-O-, -O-C(=O)-] and a linear alkylene group is more preferable, and a single bond is even more preferable.

[0214] In the above formula (a1-3), Rax ０１ The acid-dissociable group is preferably represented by the general formula (a1-r-2) or (a1-r-4) described above, and among these, the acid-dissociable group represented by the general formula (a1-r-2) is more preferred, and the group represented by the general formula (a1-r2-1) is even more preferred.

[0215] In the above formula (a1-3), Rz ０１ The alkyl group, alkyl halide, and alkoxy group in the above is preferably having 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, even more preferably 1 to 3 carbon atoms, and particularly preferably 1 or 2 carbon atoms. The alkyl group, alkyl halide, and alkoxy group may be linear or branched. Rz ０１ In this case, iodine is preferred as the halogen atom. ０１ In the alkyl halide, the halogen atom is preferably a fluorine atom, an iodine atom, or a bromine atom, with a fluorine atom being more preferred. Rz ０１ The group is preferably an alkoxy group or a hydroxyl group, with a hydroxyl group being more preferred.

[0216] In formula (a1-3), q is an integer from 0 to 3. When q is 0, it is a benzene structure; when q is 1, it is a naphthalene structure; when q is 2, it is an anthracene structure; and when q is 3, it is a tetracene structure. In formula (a1-3), n is an integer of 0 or more, preferably an integer from 0 to 5, more preferably an integer from 0 to 3, and even more preferably 1 or 2. When n is an integer of 2 or more, Rz is 2 or more. ０１These can be the same or different. In the above formula (a1-3), n ≤ q × 2 + 4. For example, if q is 1 and the structure is naphthalene, then all six hydrogen atoms of the naphthalene are Rz ０１ It may be substituted with Ya ００１ , -Ya ０１ -C(=O)-O-Rax ０１ Base, and Rz ０１ The substitution position is not particularly limited.

[0217] The following are specific examples of constituent units (a1). In each of the following formulas, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0218]

[0219]

[0220]

[0221]

[0222]

[0223]

[0224]

[0225]

[0226]

[0227] In the following equations, R α Rz represents a hydrogen atom, a methyl group, or a trifluoromethyl group. Rz represents a hydrogen atom, an alkyl group, a halogen atom, an alkyl halide, a hydroxyl group, or an alkoxy group.

[0228]

[0229]

[0230]

[0231]

[0232]

[0233] The constituent unit (a1) of component (A1) may be one type or two or more types. As for the constituent unit (a1), the constituent unit represented by formula (a1-1) or the constituent unit represented by formula (a1-3) is more preferable because it is easier to improve the characteristics (sensitivity, shape, etc.) in electron beam or EUV lithography. Among these, the acid-dissociable group (Ra) is preferred because it can be made more reactive for EB or EUV applications. １ Rax ０１ Preferably, each of these groups is an acid-dissociable group represented by the above general formula (a1-r2-1), (a1-r2-3), (a1-r2-4), or (a1-r-4), and among these, it is particularly preferable to select a cyclic group.

[0234] Alternatively, the constituent unit (a1) may include a constituent unit represented by the following general formula (a1-1-1).

[0235] [In the formula, Ra １ " is an acid-dissociable group represented by the general formula (a1-r2-1), (a1-r2-3), (a1-r2-4), or (a1-r-4). * indicates a bond.

[0236] In the above formula (a1-1-1), R, Va １ and n ａ１ R, Va in the above formula (a1-1) １ and n ａ１ It is similar to that.

[0237] The acid-dissociable groups represented by the general formulas (a1-r2-1), (a1-r2-3), (a1-r2-4), or (a1-r-4) are described above. In particular, it is preferable to select those in which the acid-dissociable group is a cyclic group, as this enhances reactivity for use in EB or EUV applications.

[0238] The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol%, more preferably 10 to 75 mol%, still more preferably 30 to 70 mol%, and particularly preferably 40 to 70 mol%, based on the total (100 mol%) of all structural units constituting the component (A1). By setting the proportion of the structural unit (a1) to be equal to or higher than the lower limit of the above preferred range, lithography properties such as sensitivity, resolution, LWR, and CDU improvement are enhanced. On the other hand, when the proportion is equal to or lower than the upper limit of the above preferred range, the balance with other structural units can be achieved, and various lithography properties become favorable.

[0239] Structural Unit (a10): The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

[0240] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya ｘ１ is a single bond or a divalent linking group. Wa ｘ１ is an aromatic hydrocarbon group which may have a substituent. n ａｘ１ is an integer of 1 or more.]

[0241] In the aforementioned formula (a10-1), R is the same as R in the aforementioned general formula (a1-1). 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 preferred, and a hydrogen atom or a methyl group is particularly preferred from the viewpoint of ease of industrial availability.

[0242] In the aforementioned formula (a10-1), Ya ｘ１ is a single bond or a divalent linking group. In the aforementioned chemical formula, Ya ｘ１ The divalent linking group in is not particularly limited, and preferred examples thereof include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like.

[0243] Ya ｘ１ is preferably a single bond, an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof, and more preferably a single bond or an ester bond [-C(=O)-O-, -O-C(=O)-].

[0244] In the aforementioned formula (a10-1), Wa ｘ１ is an aromatic hydrocarbon group which may have a substituent. Wa ｘ１ Examples of the aromatic hydrocarbon group in the above include groups obtained by removing (n ａｘ１ +1) hydrogen atoms from an aromatic ring which may have a substituent. The aromatic ring herein is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons. 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 some of the carbon atoms constituting the aforementioned aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom, and the like. Specific examples of the aromatic heterocycle include a pyridine ring, a thiophene ring, and the like. Further, Wa ｘ１ Examples of the aromatic hydrocarbon group in the above also include groups obtained by removing (n ａｘ１ +1) hydrogen atoms from an aromatic compound containing an aromatic ring which may have 2 or more substituents (for example, biphenyl, fluorene, etc.). Among the above, Wa ｘ１ is preferably a group obtained by removing (n ａｘ１ +1) hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, more preferably a group obtained by removing (n ａｘ１ +1) hydrogen atoms from benzene or naphthalene, and still more preferably a group obtained by removing (n ａｘ１ +1) hydrogen atoms from benzene.

[0245] Wa ｘ１ The aromatic hydrocarbon group in the above may or may not have a substituent. Examples of the aforementioned substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and the like. As the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the aforementioned substituent, Ya ｘ１Examples of substituents for cyclic aliphatic hydrocarbon groups in the above are similar to those listed above. The substituents are preferably linear or branched alkyl groups having 1 to 5 carbon atoms, more preferably linear or branched alkyl groups having 1 to 3 carbon atoms, even more preferably ethyl or methyl groups, and particularly preferably methyl groups. Wa ｘ１ In this context, it is preferable that the aromatic hydrocarbon group does not have substituents.

[0246] In the above formula (a10-1), n ａｘ１ is an integer of 1 or more, preferably an integer from 1 to 10, more preferably an integer from 1 to 5, even more preferably 1, 2, or 3, and particularly preferably 1 or 2.

[0247] The following are specific examples of the constituent unit (a10) represented by the above formula (a10-1). In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0248]

[0249]

[0250]

[0251] The constituent unit (a10) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent unit (a10), but it is preferable that it has constituent unit (a10). When component (A1) has constituent unit (a10), the proportion of constituent unit (a10) in component (A1) is preferably 20 to 80 mol%, more preferably 25 to 70 mol%, even more preferably 30 to 60 mol%, and particularly preferably 30 to 50 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). Setting the proportion of constituent unit (a10) above the lower limit makes it easier to increase sensitivity. On the other hand, setting it below the upper limit makes it easier to balance with other constituent units.

[0252] Constituent unit (a2): Component (A1) may or may not have constituent unit (a2) containing a lactone-containing cyclic group (excluding those corresponding to constituent unit (a1)). The lactone-containing cyclic group of constituent unit (a2) is effective in improving the adhesion of the resist film to the substrate when component (A1) is used to form a resist film. Furthermore, having constituent unit (a2) improves lithography characteristics, etc., by having effects such as appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development.

[0253] A "lactone-containing cyclic group" refers to a cyclic group that contains a ring (lactone ring) containing -O-C(=O)- within its cyclic skeleton. The lactone ring is counted as the first ring. If it consists only of a lactone ring, it is called a monocyclic group; if it also has other ring structures, it is called a polycyclic group regardless of those structures. A lactone-containing cyclic group may be a monocyclic group or a polycyclic group. Any lactone-containing cyclic group can be used in the constituent unit (a2) without any particular limitations. Specifically, examples include the groups represented by the following general formulas (a2-r-1) to (a2-r-7).

[0254] [In the formula, Ra' ２１ Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, or a lactone-containing cyclic group; A'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom (-O-) or a sulfur atom (-S-), an oxygen atom, or a sulfur atom, where n' is an integer from 0 to 2, and m' is 0 or 1. * indicates a bond (the same applies below).

[0255] In the general formulas (a2-r-1) to (a2-r-7), Ra' ２１The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, etc. Among these, the methyl group or ethyl group is preferred, and the methyl group is particularly preferred. Ra' ２１ The alkoxy group in is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the Ra' ２１ Examples of alkyl groups in this context include groups formed by linking an alkyl group with an oxygen atom (-O-). ２１ In this, a fluorine atom is preferred as the halogen atom. Ra' ２１ The halogenated alkyl group in is the Ra' ２１ Examples include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. Fluorinated alkyl groups are preferred as the halogenated alkyl group, and perfluoroalkyl groups are particularly preferred.

[0256] Ra' ２１In -COOR'' and -OC(=O)R'', R'' is a hydrogen atom, an alkyl group, or a lactone-containing cyclic group. The alkyl group in R'' may be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms. If R'' is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and is particularly preferably a methyl group or an ethyl group. If 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, examples include a group obtained by removing one or more hydrogen atoms from a monocycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; and a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as bicycloalkanes, tricycloalkanes, or tetracycloalkanes. More specifically, groups obtained by removing one or more hydrogen atoms from monocycloalkanes such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as decane and tetracyclododecane. Examples of lactone-containing cyclic groups in R'' include those similar to the groups represented by the general formulas (a²-r-1) to (a²-r-7) above. Ra' ２１ The hydroxyalkyl group in is preferably one having 1 to 6 carbon atoms, specifically the Ra' ２１ Examples include groups in which at least one hydrogen atom of the alkyl group is substituted with a hydroxyl group.

[0257] Ra' ２１ Among the above, it is preferable that each is independently a hydrogen atom or a cyano group.

[0258] 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 preferably a linear or branched alkylene group, such as a methylene group, ethylene group, n-propylene group, isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, a specific example is a group in which -O- or -S- is interposed at the end or between carbon atoms of the alkylene group, for example, -O-CH ２ -ien-CH ２ -O-CH ２ -, -S-CH ２ -ien-CH ２ -S-CH ２ Examples include the following. A'' is preferably an alkylene group or -O- having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0259] The following are specific examples of the groups represented by the general formulas (a²-r-1) to (a²-r-7).

[0260]

[0261]

[0262] Among the constituent units (a2), those derived from acrylic acid esters in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent are preferred. Such constituent units (a2) are preferably those represented by the following general formula (a2-1).

[0263] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogen having 1 to 5 carbon atoms. Ya ２１ It is a single bond or a divalent linking group. La ２１ The elements are -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, where R' represents a hydrogen atom or a methyl group. However, La ２１ If -O-, Ya ２１ It does not become -CO-. Ra ２１ This is a lactone-containing cyclic group.

[0264] In formula (a2-1) above, R is the same as above. 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 a hydrogen atom or a methyl group is particularly preferred due to their industrial availability.

[0265] In the above formula (a2-1), Ya ２１ The divalent linking group in this is not particularly limited, but suitable examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. ２１ The divalent linking group in the above general formula (a10-1) is Ya ｘ１ Examples include divalent linking groups similar to those in [the relevant context].

[0266] Ya ２１ Preferably, the group is a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0267] In the above formula (a2-1), Ya ２１ It is a single bond, La ２１ It is preferable that it be -COO- or -OCO-.

[0268] In the formula (a2-1), Ra ２１ Ra is a lactone-containing cyclic group. ２１ Suitable lactone-containing cyclic groups in this compound include the groups represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above.

[0269] The constituent unit (a2) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent unit (a2). If component (A1) has constituent unit (a2), the proportion of constituent unit (a2) is preferably 1 to 20 mol%, more preferably 1 to 15 mol%, and even more preferably 1 to 10 mol%, relative to the total (100 mol%) of all constituent units that make up component (A1). If the proportion of constituent unit (a2) is above the preferred lower limit, the effects of including constituent unit (a2) are sufficiently obtained due to the effects described above, and if it is below the upper limit, a balance with other constituent units can be maintained, resulting in good lithography characteristics in various fields.

[0270] Constituent unit (a5): Component (A1) may or may not have a constituent unit (a5) that generates acid upon exposure. Known constituent units (a5) can be used. Having a constituent unit (a5) makes it easier for the acid generated upon exposure to be uniformly distributed within the resist film. Examples of constituent units (a5) include a constituent unit containing the structure described in component (B) below. For example, an example of a constituent unit (a5) is a constituent unit containing a structure represented by any of the general formulas (b-1) to (b-3) below. For example, a constituent unit represented by the following general formula (a5-1) is preferred as a constituent unit (a5).

[0271] [In the formula, R ｍ This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La ５０ This is a divalent linking group or a single bond. Ra ５０ n is a divalent hydrocarbon group which may have substituents. ａ５ It is an integer between 0 and 2. ５１ It is a divalent linking group. ５ This is a divalent linking group or a single bond. Ra ５１ and Ra ５２ Each of these is independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group. n5 is an integer from 1 to 4. m is an integer of 1 or more, and M' ｍ＋This is an onium cation with a valence of m.

[0272] {Anion part} In the above formula (a5-1), R ｍ R is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. ｍ The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically including methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. Fluorine is particularly preferred as the halogen atom in the halogenated alkyl group. ｍ Preferably, the group consists of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, with the hydrogen atom or methyl group being the most preferred due to their industrial availability.

[0273] In the formula (a5-1), La ５０ This is a divalent linking group or a single bond. La ５０ The divalent linking group in is not particularly limited, but preferred examples include a divalent hydrocarbon group which may have substituents, and a divalent linking group which contains a heteroatom, respectively. ｘ１ The divalent linking groups in the above are similar to the divalent hydrocarbon groups that may have substituents and divalent linking groups containing heteroatoms, as exemplified. ５０ Preferably, the bonds are ester bonds [-C(=O)-O-, -O-C(=O)-], ether bonds (-O-), linear or branched alkylene groups, aromatic hydrocarbon groups or combinations thereof, or single bonds. Among these, La ５As, an ester bond [-C(=O)-O-, -O-C(=O)-] or a single bond is more preferred, and an ester bond [-C(=O)-O-, -O-C(=O)-] is still more preferred.

[0274] In the above formula (a5-1), Ra ５０ is a divalent hydrocarbon group which may have a substituent. The Ra ５０ divalent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0275] ·· Ra ５０ aliphatic hydrocarbon group The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and usually is preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, and the like.

[0276] ··· Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferred, and specific examples thereof include a methylene group [-CH ２ -], an ethylene group [-(CH ２ ) ２ -], a trimethylene group [-(CH ２ ) ３ -], a tetramethylene group [-(CH ２ ) ４ -], a pentamethylene group [-(CH ２ ) ５ -], and the like. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specific examples thereof include -CH(CH ３ )-, -CH(CH ２ CH ３ )-, -C(CH３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkyl methylene groups such as -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ -, -C(CH ２ CH ３ ) ２ -CH ２ - Alkyl ethylene groups such as -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２ Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0277] The linear or branched aliphatic hydrocarbon group described above may or may not have substituents. Examples of substituents include fluorine atoms, fluorinated alkyl groups having 1 to 5 carbon atoms substituted with fluorine atoms, and carbonyl groups.

[0278] ...Aliphatic hydrocarbon groups containing a ring in their structure Examples of aliphatic hydrocarbon groups containing a ring in their structure include cyclic aliphatic hydrocarbon groups (groups with two hydrogen atoms removed from an aliphatic hydrocarbon ring) which may contain substituents containing heteroatoms in their ring structure, groups in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group are the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms have been removed from a monocycloalkane is preferred. As a monocycloalkane, those having 3 to 6 carbon atoms are preferred, and specifically examples include cyclopentane and cyclohexane. As for the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferred, and as the polycycloalkane, those having 7 to 12 carbon atoms are preferred, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include decane and tetracyclododecane.

[0279] The cyclic aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and carbonyl groups. Preferably, the alkyl group has 1 to 5 carbon atoms, and most preferably it is a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Preferably, the alkoxy group has 1 to 5 carbon atoms, and more preferably it is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, or tert-butoxy group, with methoxy and ethoxy groups being the most preferred. Examples of halogen atoms as substituents include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being preferred. Examples of alkyl halides as substituents include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. The cyclic aliphatic hydrocarbon group may have some of the carbon atoms constituting its ring structure substituted with substituents containing heteroatoms. Substituents containing the heteroatom include -O-, -C(=O)-O-, -S-, and -S(=O). ２ -, -S (=O) ２ -O- is preferred.

[0280] ...Ra ５０The aromatic hydrocarbon group in this context is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. Specific examples of aromatic hydrocarbon groups include: a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) in which one hydrogen atom is replaced by an alkylene group (e.g., a group obtained by removing one more hydrogen atom from the aryl group in an arylalkyl group such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0281] The aromatic hydrocarbon group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, and hydroxyl groups. The alkyl group substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Examples of alkoxy groups, halogen atoms, and alkyl halides as substituents include those exemplified as substituents that substitute for hydrogen atoms in the cyclic aliphatic hydrocarbon group.

[0282] In the above formula (a5-1), n ａ５ is an integer between 0 and 2. Among the above, Ra ５０ Preferably, the aliphatic hydrocarbon group is an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably a polycyclic or monocyclic alicyclic hydrocarbon group which may have substituents. Alternatively, among the above, Ra ５０ Aromatic hydrocarbon groups are preferred.

[0283] n ａ５ If it is 2, then two Ra ５０ These may all be alicyclic hydrocarbon groups which may have substituents, or they may all be aromatic hydrocarbon groups which may have substituents, or they may be a combination of alicyclic hydrocarbon groups which may have substituents and aromatic hydrocarbon groups which may have substituents.

[0284] In the formula (a5-1), La ５１ It is a divalent linking group. La ５１Examples of divalent linking groups in this context include non-hydrocarbon oxygen atom-containing linking groups such as oxygen atoms (ether bond: -O-), ester bonds (-C(=O)-O-), oxycarbonyl groups (-O-C(=O)-), amide bonds (-C(=O)-NH-), carbonyl groups (-C(=O)-), and carbonate bonds (-O-C(=O)-O-); and combinations of these non-hydrocarbon oxygen atom-containing linking groups with alkylene groups. In addition to these combinations, sulfonyl groups (-SO) may be added. ２ -) may be linked. Examples of such divalent linking groups include the linking groups represented by the following general formulas (L-al-1) to (L-al-8). Note that in the following general formulas (L-al-1) to (L-al-8), Ra in the above formula (a5-1) ５０ The combination with this is V' in the following general formulas (L-al-1) to (L-al-8). １０１ That is the case.

[0285] [In the formula, V' １０１ V' is a single bond or an alkylene group having 1 to 5 carbon atoms. １０２ [This refers to a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]

[0286] V' １０２ The divalent saturated hydrocarbon group in is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0287] V' １０１ and V' １０２ The alkylene group in V' may be a linear alkylene group or a branched alkylene group, but a linear alkylene group is preferred. １０１ and V' １０２ Specifically, the alkylene group in this case is the methylene group [-CH ２ -come; -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkylmethylene groups such as; ethylene groups [-CH ２ CH ２ -come; -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ - Alkylethylene groups such as; trimethylene group (n-propylene group) [-CH ２ CH ２ CH ２ -come; -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as; tetramethylene groups [-CH ２ CH ２ CH ２ CH ２ -come; -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２ - Alkyltetramethylene groups such as; pentamethylene groups [-CH ２ CH ２ CH ２ CH ２ CH ２ -] are some examples. Also, V' １０１ or V' １０２Some of the methylene groups in the alkylene group may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a divalent group obtained by removing one more hydrogen atom from a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group), and more preferably a cyclohexylene group, a 1,5-adamantilene group, or a 2,6-adamantilene group.

[0288] La ５１ Preferably, the linking group is a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, more preferably the linking groups represented by formulas (L-al-1) to (L-al-5) and (L-al-8), respectively, and even more preferably the linking group represented by formula (L-al-3) or (L-al-8).

[0289] In the above formula (a5-1), Ya ５ This is a divalent linking group or a single bond. ５ The divalent linking group in this is not particularly limited, but suitable examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. ５ In the above, the divalent hydrocarbon group which may have substituents, and the divalent linking group which contains a heteroatom, are as follows: ｘ１ This is similar to the divalent linking groups exemplified in the above, such as divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Among the above, Ya ５ Preferably, the alkylene group is linear or branched, or a single bond is preferred, with a single bond being more preferred.

[0290] In the formula (a5-1), Ra ５１ and Ra ５２ Each of these is independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group. Ra ５１ and Ra ５２ The fluorinated alkyl group in is preferably a linear or branched fluorinated alkyl group having 1 to 5 carbon atoms, and more preferably a trifluoromethyl group. In formula (a5-1), SO ３ － Ra bonded to the adjacent carbon atom ５１and Ra ５２ From the viewpoint of acid strength, it is preferable that at least one of them is a fluorine atom.

[0291] In the above formula (a5-1), n5 is an integer from 1 to 4, and is preferably 1, 2, or 3.

[0292] {Cation part} In the above formula (a5-1), M' ｍ＋ This represents an m-valent onium cation. Among these, M' ｍ＋ The sulfonium cation and iodonium cation are preferred. m is an integer of 1 or more.

[0293] Preferred cation portion ((M' ｍ＋ ) １／ｍ Examples of these include organic cations represented by the following general formulas (ca-1) to (ca-3).

[0294] [In the formula, R ２０１ ~R ２０７ Each of these independently represents an optionally substituted aryl group, an optionally substituted alkyl group, or an optionally substituted alkenyl group. ２０１ ~R ２０３ , R ２０６ ~R ２０７ These atoms may bond to each other to form a ring with the sulfur atom in the formula. ２０８ ~R ２０９ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ２１０ This may be an aryl group having a substituent, an alkyl group having a substituent, an alkenyl group having a substituent, or an -SO group having a substituent. ２ - Contains a cyclic group. L ２０１ This represents -C(=O)- or -C(=O)-O-.

[0295] In the above general formulas (ca-1) to (ca-3), R ２０１ ~R ２０７ Examples of aryl groups in this compound include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. ２０１ ~R ２０７The alkyl group in is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. ２０１ ~R ２０７ The alkenyl group in is preferably one with 2 to 10 carbon atoms. ２０１ ~R ２０７ , and R ２１０ Examples of substituents that may be present include alkyl groups, halogen atoms, alkyl halides, carbonyl groups, cyano groups, amino groups, aryl groups, and the groups represented by the general formulas (ca-r-1) to (ca-r-8) described above.

[0296] In the above general formulas (ca-1) to (ca-3), R ２０１ ~R ２０３ , R ２０６ ~R ２０７ When these atoms bond to each other and form a ring with the sulfur atom in the formula, they can be heteroatoms such as sulfur, oxygen, and nitrogen atoms, or carbonyl groups, -SO-, -SO ２ -, -SO ３ -, -COO-, -CONH- or -N(R Ｎ )-(the R Ｎ is an alkyl group having 1 to 5 carbon atoms. It may also be bonded via a functional group such as . The formed ring is preferably a 3 to 10-membered ring, and particularly preferably a 5 to 7-membered ring, including the sulfur atom in its ring skeleton. Specific examples of the formed ring include, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthlene ring, a phenoxatiyne ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring, and the like.

[0297] R ２０８ ~R ２０９ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. If an alkyl group is present, it may bond to each other to form a ring.

[0298] R ２１０This may be an aryl group having a substituent, an alkyl group having a substituent, an alkenyl group having a substituent, or an -SO group having a substituent. ２ - Contains a cyclic group. R ２１０ Examples of aryl groups in this compound include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. ２１０ The alkyl group in is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. ２１０ The alkenyl group in is preferably one with 2 to 10 carbon atoms. ２１０ In, -SO ２ - Any cyclic group can be used without any particular limitations. Specifically, the groups represented by the following general formulas (b5-r-1) to (b5-r-4) can be used, such as "-SO ２ A polycyclic group containing a polycyclic group is preferred, and a group represented by the general formula (b5-r-1) is more preferred.

[0299] [In the formula, Rb' ５１ Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, or -SO ２ - It is a cyclic group containing; B'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n' is an integer from 0 to 2. * indicates a bond.

[0300] In the general formulas (b5-r-1) to (b5-r-2) above, B'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom. B'' is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and even more preferably a methylene group.

[0301] In the above general formulas (b5-r-1) to (b5-r-4), Rb' ５１Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group, and among these, each is preferably independently a hydrogen atom or a cyano group.

[0302] Specific examples of the groups represented by the general formulas (b5-r-1) to (b5-r-4) are given below. In the formulas, "Ac" indicates an acetyl group.

[0303]

[0304]

[0305]

[0306] Specific examples of suitable cations represented by the above formula (ca-1) include the cations represented by the following chemical formulas.

[0307]

[0308]

[0309] [In the formula, g1, g2, and g3 represent the number of repetitions, where g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 1 to 20.]

[0310]

[0311]

[0312] [In the formula, R” ２０１ The substituent is a hydrogen atom or a substituent, and examples of such substituents include alkyl groups, halogen atoms, alkyl halides, cyano groups, amino groups, aryl groups, and groups represented by the general formulas (ca-r-1) to (ca-r-8), respectively.

[0313]

[0314] Specific examples of suitable cations represented by the formula (ca-2) include diphenyliodonium cation and bis(4-tert-butylphenyl)iodonium cation.

[0315] Specific examples of suitable cations represented by the above formula (ca-3) include the cations represented by the following formulas (ca-3-1) to (ca-3-6).

[0316]

[0317] The cation portion in the above formula (a5-1) ((M' ｍ＋ ) １／ｍ As the cation, a sulfonium cation is preferred, the cations represented by formulas (ca-1) to (ca-3) are more preferred, the cation represented by formula (ca-1) is even more preferred, and the cations represented by formulas (ca-1-1) to (ca-1-84) are particularly preferred. Particularly from the viewpoint of increasing sensitivity, as the preferred cation represented by formula (ca-1), it is preferable that it has electron-withdrawing groups such as a fluorine atom, a fluorinated alkyl group, or a sulfonyl group as a substituent. For example, a cation selected from the group consisting of the above chemical formulas (ca-1-44) and (ca-1-71) to (ca-1-84) is particularly preferred.

[0318] The following are preferred examples of the constituent unit (a5). In the following formula, R α m and M' represent a hydrogen atom, a methyl group, or a trifluoromethyl group. ｍ＋ These are m and M' in the above general formula (a5-1). ｍ＋ It is similar to that.

[0319]

[0320]

[0321]

[0322] The constituent unit (a5) of component (A1) may be one type or two or more types. When component (A1) has constituent unit (a5), the proportion of constituent unit (a5) in component (A1) is preferably 5 to 25 mol%, more preferably 10 to 20 mol%, and even more preferably 15 to 20 mol%, relative to the total (100 mol%) of all constituent units that make up component (A1). If the proportion of constituent unit (a5) is above the lower limit of the above preferred range, it becomes easier to achieve further increases in sensitivity and improvements in resolution. On the other hand, if it is below the upper limit of the above preferred range, it becomes easier to balance with other constituent units.

[0323] Constituent unit (a6): Constituent unit (a6) is a constituent unit that has acid diffusion control properties. Component (A1) may or may not contain constituent unit (a6). Constituent unit (a6) can be one of known types. Examples of constituent unit (a6) include constituent units containing the structures described in components (D1) and (D2) below. For example, a constituent unit containing a structure represented by any of the general formulas (d1-1) to (d1-3) below can be used.

[0324] The constituent unit (a6) of component (A1) may be one type or two or more types. When component (A1) has constituent unit (a6), the proportion of constituent unit (a6) in component (A1) is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and even more preferably 3 to 10 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). If the proportion of constituent unit (a6) is above the lower limit of the above preferred range, it becomes easier to achieve even higher sensitivity. On the other hand, if it is below the upper limit of the above preferred range, it becomes easier to balance with other constituent units.

[0325] Constituent unit (a8): Constituent unit (a8) is a constituent unit derived from the compound represented by the following general formula (a8-1). Component (A1) may or may not have constituent unit (a8).

[0326] [In the formula, W ２ This is a polymerizable group-containing group. ｘ２ is a single bond or (nａｘ２ It is a linking group with a +1 valence. ｘ２ and W ２ It may form a fused ring. １ R is a fluorinated alkyl group having 1 to 12 carbon atoms. ２ R is an organic group having 1 to 12 carbon atoms, which may contain a fluorine atom, or a hydrogen atom. ２ and Ya ｘ２ These may be bonded to each other to form a ring structure. ａｘ２ [This is an integer between 1 and 3.]

[0327] W ２ In the context of polymerizable group-containing groups, "polymerizable group" refers to a group that enables a compound containing a polymerizable group to polymerize by radical polymerization or the like, and includes, for example, a group containing multiple bonds between carbon atoms, such as an ethylenic double bond.

[0328] The polymerizable group-containing group may be a group composed solely of a polymerizable group, or a group composed of a polymerizable group and other groups other than the polymerizable group. Examples of other groups other than the polymerizable group include divalent hydrocarbon groups which may have substituents, and divalent linking groups containing heteroatoms. An example of a polymerizable group-containing group is a group with the chemical formula: C(R Ｘ１１ ) (Caution Ｘ１２ ) = C(R Ｘ１３ )-Ya ｘ０ The group represented by - is preferably mentioned. In this chemical formula, R Ｘ１１ , R Ｘ１２ and R Ｘ１３ These are, respectively, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Ya ｘ０ It is a single bond or a divalent linking group.

[0329] Ya ｘ２ and W ２ The condensed ring formed by these is W ２ Polymerizable groups of the site and Ya ｘ２ The condensed ring formed by and W ２ Other groups besides the polymerizable group of the site and Ya ｘ２ A condensed ring formed by these is an example. ｘ２ and W ２ The fused ring formed by these two components may have substituents.

[0330] The following shows specific examples of constituent units (a8). In the following formula, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0331]

[0332] Among the above examples, the constituent unit (a8) is preferably at least one selected from the group consisting of constituent units represented by the chemical formulas (a8-1-01) to (a8-1-04), (a8-1-06), (a8-1-08), (a8-1-09), and (a8-1-10), and more preferably at least one selected from the group consisting of constituent units represented by the chemical formulas (a8-1-01) to (a8-1-04) and (a8-1-09).

[0333] The constituent units (a8) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent units (a8). The proportion of constituent units (a8) in component (A1) is preferably 0 to 50 mol%, and more preferably 0 to 30 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0334] The (A1) component contained in the resist composition may be used alone or in combination of two or more types.

[0335] Examples of component (A1) include polymer compounds having constituent units (a0) and (a1); polymer compounds having constituent units (a0) and (a10); and polymer compounds having constituent units (a0), (a1) and (a10). Component (A1) is preferably a polymer compound consisting of constituent units (a0), (a1) and (a10).

[0336] In a polymer compound consisting of constituent units (a0), (a1), and (a10), the proportion of constituent unit (a0) is preferably 0.5 to 60 mol%, more preferably 1 to 40 mol%, even more preferably 5 to 30 mol%, and particularly preferably 10 to 20 mol%, based on the total amount of all constituent units constituting the polymer compound (100 mol%). The proportion of constituent unit (a1) in the polymer compound is preferably 5 to 80 mol%, more preferably 10 to 75 mol%, even more preferably 30 to 70 mol%, and particularly preferably 40 to 70 mol%, based on the total amount of all constituent units constituting the polymer compound (100 mol%). The proportion of constituent unit (a10) in the polymer compound is preferably 10 to 80 mol%, more preferably 15 to 70 mol%, even more preferably 20 to 60 mol%, and particularly preferably 20 to 50 mol%, based on the total amount of all constituent units constituting the polymer compound (100 mol%).

[0337] Such component (A1) can be produced by dissolving monomers that induce each constituent unit in a polymerization solvent, and then adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate (e.g., V-601) and polymerizing the mixture. Alternatively, such component (A1) can be produced by dissolving a monomer that induces constituent unit (a0) and a monomer that induces any constituent unit (e.g., constituent unit (a10), constituent unit (a1), etc.) in a polymerization solvent, adding a radical polymerization initiator as described above and polymerizing the mixture, and then performing a deprotection reaction as appropriate. Note that during polymerization, for example, HS-CH ２ -CH ２ -CH ２ -C(CF ３ ) ２ By using a chain transfer agent such as -OH in combination, -C (CF) can be attached to the terminal. ３ ) ２ -OH groups may also be introduced. Copolymers into which hydroxyalkyl groups, in which some of the hydrogen atoms of the alkyl group are replaced with fluorine atoms, are introduced are effective in reducing development defects and LER (line edge roughness: uneven unevenness of the line sidewall).

[0338] The weight-average molecular weight (Mw) of component (A1) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and even more preferably 5,000 to 30,000. If the Mw of component (A1) is below the preferred upper limit of this range, it has sufficient solubility in resist solvents for use as a resist, and if it is above the preferred lower limit of this range, it has good dry etching resistance and a good cross-sectional shape of the resist pattern. The dispersion degree (Mw / Mn) of component (A1) is not particularly limited, but is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.0 to 2.0. Mn represents the number-average molecular weight.

[0339] Preferred (A1) components include, for example, the polymer compounds represented by the following formulas (A1-1) to (A1-36).

[0340]

[0341]

[0342]

[0343]

[0344]

[0345] Component (A1) is preferably selected from the group consisting of polymer compounds represented by the above formulas (A1-1) to (A1-36).

[0346] Alternatively, since sensitivity is more easily improved, it is preferably selected from the group consisting of polymer compounds represented by formulas (A1-3), (A1-8), (A1-12), (A1-14), (A1-18), (A1-19), (A1-21), (A1-22), (A1-24), (A1-26), and (A1-30) to (A1-36). More preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-8), (A1-12), (A1-18), (A1-19), (A1-21), (A1-22), and (A1-30) to (A1-36).

[0347] Alternatively, since roughness is more easily reduced, it is preferably selected from the group consisting of polymer compounds represented by formulas (A1-1), (A1-2), (A1-4), (A1-5), (A1-7), (A1-9) to (A1-11), (A1-13), and (A1-15) to (A1-34). More preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-15) to (A1-36). Even more preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-15) to (A1-23), (A1-25), and (A1-27) to (A1-36).

[0348] Alternatively, because etching resistance is more easily improved, it is preferably selected from the group consisting of polymer compounds represented by formulas (A1-3), (A1-9), (A1-13), (A1-15) to (A1-31), (A1-34), and (A1-36). More preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-18) to (A1-30), (A1-34), and (A1-36).

[0349] Alternatively, from the viewpoint of achieving both high sensitivity, reduced roughness, and improved etching resistance, it is preferably selected from the group consisting of polymer compounds represented by formulas (A1-3), (A1-8), (A1-9), (A1-12) to (A1-36). More preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-15) to (A1-36). Even more preferably, it is selected from the group consisting of polymer compounds represented by formulas (A1-18), (A1-19), (A1-21), (A1-22), (A1-24), (A1-26), (A1-30), (A1-31), (A1-34), and (A1-36).

[0350] Regarding component (A2), the resist composition of this embodiment may also include, as component (A), a base component that does not fall under component (A1) and whose solubility in the developer changes due to the action of an acid (hereinafter referred to as "component (A2)"). Component (A2) is not particularly limited and may be arbitrarily selected from a large number of base components conventionally known for chemically amplified resist compositions. Component (A2) may be a single polymer compound or a low molecular weight compound, or two or more may be used in combination.

[0351] The proportion of component (A1) in component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 75% by mass or more, and may also be 100% by mass, based on the total mass of component (A). When the proportion is 25% by mass or more, sensitivity tends to improve, and a resist pattern with excellent lithography characteristics such as resolution and roughness, as well as excellent etching resistance, is more easily formed.

[0352] In the resist composition of this embodiment, the content of component (A) may be adjusted according to the resist film thickness to be formed.

[0353] <Other Components> In addition to component (A) described above, the resist composition of this embodiment may further contain other components. Examples of other components include components (B), (D), (E), (F), and (S) shown below.

[0354] ≪Acid Generating Agent Component (B)≫ The resist composition of this embodiment may contain an acid generating agent component (B) that generates acid upon exposure. Component (B) is not particularly limited, and any acid generating agent previously proposed for chemically amplified resist compositions can be used. Examples of such acid generating agents include onium salt-based acid generating agents such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generating agents; diazomethane-based acid generating agents such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl) diazomethanes; nitrobenzyl sulfonate-based acid generating agents, iminosulfonate-based acid generating agents, disulfone-based acid generating agents, and many others. Component (B) may be in the form of a compound, incorporated into component (A1) as the above-mentioned constituent unit (a5), or in both forms.

[0355] Examples of onium salt-based acid generators include the compound represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), the compound represented by the general formula (b-2) (hereinafter also referred to as "component (b-2)"), or the compound represented by the general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0356] [In the formula, R １０１ and R １０４ ~R １０８ Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. １０４ and R １０５ These may be bonded to each other to form a ring structure. １０２ This is a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. １０１ This is a divalent linking group or single bond containing an oxygen atom. １０１ ~V １０３ Each of these is independently a single bond, an alkylene group, or a fluorinated alkylene group. However, Y １０１ and V １０１ They cannot be single bonds at the same time. １０１ ~L １０２Each of these is independently either a single bond or an oxygen atom. １０３ ~L １０５ These are, independently, single bonds, -CO-, or -SO-. ２ - is true. m is an integer greater than or equal to 1, and M' ｍ＋ This is an onium cation with a positive (m) charge.

[0357] {Anion part} • In the anion formula (b-1) of component (b-1), R １０１ This is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents.

[0358] A cyclic group which may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group is preferably saturated.

[0359] R １０１ The aromatic hydrocarbon group in is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in substituents. １０１ Specific examples of aromatic rings in aromatic hydrocarbon groups include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, nitrogen atoms, etc. １０１Specific examples of aromatic hydrocarbon groups in this context include groups obtained by removing one hydrogen atom from the aromatic ring (aryl groups: for example, phenyl groups, naphthyl groups, etc.), and groups in which one of the hydrogen atoms of the aromatic ring is substituted with an alkylene group (for example, benzyl groups, phenethyl groups, 1-naphthylmethyl groups, etc.). The number of carbon atoms in the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0360] R １０１ The cyclic aliphatic hydrocarbon group in this context refers to an aliphatic hydrocarbon group that contains a ring in its structure. Examples of aliphatic hydrocarbon groups containing a ring in their structure include alicyclic hydrocarbon groups (groups from which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups 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. A preferred monocyclic alicyclic hydrocarbon group is a group from which one or more hydrogen atoms have been removed from a monocycloalkane. The preferred monocycloalkane has 3 to 6 carbon atoms, and specifically includes cyclopentane and cyclohexane. A preferred polycyclic alicyclic hydrocarbon group is a group from which one or more hydrogen atoms have been removed from a polycycloalkane, and the preferred polycycloalkane has 7 to 30 carbon atoms. Among these, the polycycloalkanes include adamantane, norbornane, isobornane, and tricyclo[5.2.1.0 ２，６ Polycycloalkanes having a cross-linked ring system polycyclic skeleton, such as decane and tetracyclododecane; polycycloalkanes having a fused ring system polycyclic skeleton, such as a cyclic group having a steroid skeleton, are more preferred.

[0361] Among them, R １０１The cyclic aliphatic hydrocarbon group in is preferably a monocycloalkane or polycycloalkane from which one or more hydrogen atoms have been removed, more preferably a polycycloalkane from which one hydrogen atom has been removed, even more preferably an adamantyl group or a norbornyl group, and particularly preferably an adamantyl group.

[0362] The linear aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 1 to 10 carbon atoms, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. A linear alkylene group is preferred as the linear aliphatic hydrocarbon group, specifically a methylene group [-CH₂]. ２ -], ethylene group [- (CH ２ ) ２ -], trimethylene group [-(CH ２ ) ３ -], tetramethylene group [-(CH ２ ) ４ -], pentamethylene group [-(CH ２ ) ５ Examples include -]. The branched aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 2 to 10 carbon atoms, more preferably 3 to 6, even more preferably 3 or 4, and most preferably 3. A branched alkylene group is preferred as the branched aliphatic hydrocarbon group, specifically -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkyl methylene groups such as -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH２ -, -CH(CH ２ CH ３ )CH ２ -, -C(CH ２ CH ３ ) ２ -CH ２ - Alkyl ethylene groups such as -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２ Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0363] Also, R １０１ The cyclic hydrocarbon group in may contain heteroatoms, such as heterocycles. Specifically, lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), and -SO groups represented by the general formulas (b5-r-1) to (b5-r-4), respectively. ２ - Examples include cyclic groups and heterocyclic groups represented by the chemical formulas (r-hr-1) to (r-hr-16), respectively.

[0364] R １０１Examples of substituents on the cyclic group include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, and nitro groups. C1-C5 alkyl groups are preferred as substituents. C1-C5 alkoxy groups are preferred as substituents, with methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, and tert-butoxy groups being more preferred, and methoxy and ethoxy groups being most preferred. Fluorine, bromine, and iodine atoms are preferred as substituents. C1-C5 alkyl halides are examples of alkyl groups, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms are substituted with the halogen atoms. Carbonyl groups as substituents include methylene groups (-CH4) that constitute the cyclic hydrocarbon group. ２ It is a substituting group for -).

[0365] R １０１ The cyclic hydrocarbon group in may be a fused ring group containing a fused ring formed by the fusion of an aliphatic hydrocarbon ring and an aromatic ring. Examples of the fused ring include a polycycloalkane having a bridging ring system with one or more aromatic rings fused to it. Specific examples of the bridging ring system polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring group is preferably a group containing a fused ring formed by the fusion of two or three aromatic rings to a bicycloalkane, and more preferably a group containing a fused ring formed by the fusion of two or three aromatic rings to bicyclo[2.2.2]octane. １０１ Specific examples of fused ring groups in this context include the groups represented by the following formulas (r-br-1) to (r-br-2). In the formulas, * represents Y in formula (b-1). １０１ This represents a coupling that connects to something.

[0366]

[0367] R １０１Examples of substituents that the fused ring group in R may have include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, aromatic hydrocarbon groups, alicyclic hydrocarbon groups, etc. The alkyl groups, alkoxy groups, halogen atoms, and alkyl halides as substituents of the fused ring group are as described above. １０１ Examples of substituents for cyclic groups include those similar to those listed in the above. Aromatic hydrocarbon groups as substituents for the fused cyclic group include groups obtained by removing one hydrogen atom from an aromatic ring (aryl groups: e.g., phenyl group, naphthyl group, etc.), groups in which one hydrogen atom of the aromatic ring is replaced by an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.), and heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-16). Alicyclic hydrocarbon groups as substituents for the fused cyclic group include groups obtained by removing one hydrogen atom from monocycloalkanes such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ ] Groups obtained by removing one hydrogen atom from polycycloalkanes such as decane and tetracyclododecane; lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), respectively; -SO groups represented by the general formulas (b5-r-1) to (b5-r-4), respectively. ２ - Containing cyclic groups; examples include heterocyclic groups represented by formulas (r-hr-7) to (r-hr-16), respectively.

[0368] A chain-like alkyl group which may have substituents: R １０１The linear alkyl group may be linear or branched. Linear alkyl groups preferably have 1 to 20 carbon atoms, more preferably 1 to 15, and most preferably 1 to 10. Branched alkyl groups preferably have 3 to 20 carbon atoms, more preferably 3 to 15, and most preferably 3 to 10. Specifically, examples include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

[0369] A chain-like alkenyl group which may have substituents: R １０１ The linear alkenyl group may be linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Examples of branched alkenyl groups include 1-methylvinyl groups, 2-methylvinyl groups, 1-methylpropenyl groups, and 2-methylpropenyl groups. Among the linear alkenyl groups listed above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0370] R １０１ Examples of substituents in the chain-like alkyl or alkenyl group include alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, amino groups, and the above R １０１ Examples include cyclic groups in this context.

[0371] In formula (b-1), Y １０１ Y is a single bond or a divalent linking group containing an oxygen atom. １０１ If Y is a divalent linking group containing an oxygen atom, １０１It may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms, etc. Examples of divalent linking groups containing oxygen atoms include the linking groups represented by the above general formulas (L-al-1) to (L-al-8). Note that in the following general formulas (L-al-1) to (L-al-8), R in formula (b-1) above １０１ The combination with this is V' in the following general formulas (L-al-1) to (L-al-8). １０１ That is the case.

[0372] In formula (b-1), V １０１ These are single bonds, alkylene groups, or fluorinated alkylene groups. Among them, V １０１ It is preferable that the fluorinated alkylene group is a single bond or a linear fluorinated alkylene group having 1 to 4 carbon atoms.

[0373] In formula (b-1), R １０２ R is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. １０２ It is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0374] A specific example of the anion part represented by formula (b-1) is, for example, Y １０１ When it is a single bond, examples include fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anions and perfluorobutanesulfonate anions; Y １０１ When is a divalent linking group containing an oxygen atom, anions represented by any of the following formulas (an-1) to (an-3) are included.

[0375] [In the formula, R” １０１ R” １０２This includes an aliphatic cyclic group which may have substituents, a fused cyclic group represented by formula (r-br-1) or formula (r-br-2), a lactone-containing cyclic group represented by the general formula (a2-r-1), formula (a2-r-3) to (a2-r-7), respectively, or -SO represented by the general formula (b5-r-1) to (b5-r-4), respectively. ２ - Contains a cyclic group. R'' １０３ This is an optionally substituted aromatic cyclic group, an optionally substituted aliphatic cyclic group, or an optionally substituted linear alkenyl group. １０１ This is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. １０２ [wherein 'v' is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms; where 'v' is an independent integer from 0 to 3, where 'q' is an independent integer from 0 to 20, and where 'n' is 0 or 1.]

[0376] R" １０１ , R” １０２ and R” １０３ The aliphatic cyclic group which may have substituents is R in formula (b-1) above. １０１ It is preferable that the substituent is the group exemplified as a cyclic aliphatic hydrocarbon group in formula (b-1). １０１ Examples include substituents similar to those that may be substituted for the cyclic aliphatic hydrocarbon group in the above.

[0377] R" １０１ and R” １０３ The aromatic cyclic group which may have substituents in formula (b-1) is R １０１ It is preferable that the substituent is the group exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group in formula (b-1). １０１ Examples include substituents similar to those that may be substituted for the aromatic hydrocarbon group in the above.

[0378] R" １０１ The chain-like alkyl group which may have substituents in formula (b-1) is R １０１ It is preferable that the group is one of the examples given as a chain-like alkyl group in R''. １０３The chain-like alkenyl group which may have substituents in formula (b-1) is R １０１ It is preferable that the group is one of the examples given as a chain-like alkenyl group in the formula.

[0379] • In the anionic formula (b-2) of component (b-2), R １０４ , R １０５ Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of them is R in formula (b-1). １０１ Similar examples can be given. However, R １０４ , R １０５ These may be bonded to each other to form a ring. １０４ , R １０５ The linear alkyl group is preferably a substituted linear alkyl group, more preferably a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. The number of carbon atoms in the linear alkyl group is preferably 1 to 10, more preferably 1 to 7, and even more preferably 1 to 3. １０４ , R １０５ The number of carbon atoms in the chain-like alkyl group is preferably small within the above range of carbon atoms, for reasons such as good solubility in the resist solvent. １０４ , R １０５ In the chain-like alkyl group, the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acidity and the better the transparency to high-energy light and electron beams below 250 nm, which is preferable. The proportion of fluorine atoms in the chain-like alkyl group, i.e., the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms. In formula (b-2), V １０２ , V １０３ These are, independently, a single bond, an alkylene group, or a fluorinated alkylene group, and each is V in formula (b-1). １０１ Similar examples include the following. In equation (b-2), L １０１ , L １０２Each of these is either a single bond or an oxygen atom, independently of the others.

[0380] • In the anionic formula (b-3) of component (b-3), R １０６ ~R １０８ Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of them is R in formula (b-1). １０１ Similar examples can be given. In equation (b-3), L １０３ ~L １０５ These are, independently, single bonds, -CO-, or -SO-. ２ - is the case.

[0381] Among the above, the anion portion of component (B) is preferably the anion in component (b-1), and more preferably the anion represented by formula (an-1).

[0382] {Cation part} In the above formulas (b-1), (b-2), and (b-3), M' ｍ＋ This represents an m-valent onium cation. Among these, sulfonium cations and iodonium cations are preferred. m is an integer of 1 or more.

[0383] As the cation portion of component (B), a sulfonium cation is preferred, the cations represented by formulas (ca-1) to (ca-3) are more preferred, the cation represented by formula (ca-1) is even more preferred, and the cations represented by formulas (ca-1-1) to (ca-1-84) are particularly preferred.

[0384] In the resist composition of this embodiment, component (B) may be used alone or in combination of two or more types. When the resist composition contains component (B), the content of component (B) in the resist composition is preferably less than 50 parts by mass, more preferably 5 to 45 parts by mass, and even more preferably 10 to 43 parts by mass, per 100 parts by mass of component (A). Setting the content of component (B) within the above preferred range makes it easier to obtain a uniform solution when each component of the resist composition is dissolved in an organic solvent, and thus improves the storage stability of the resist composition, which is preferable.

[0385] ≪Basic Component (D)≫ In addition to component (A), the resist composition of this embodiment may contain a basic component (component (D)) that traps the acid generated by exposure (i.e., controls the diffusion of the acid). Component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure in the resist composition. Examples of component (D) include a photo-decayable base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its acid diffusion control properties, and a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not fall under component (D1). Among these, a photo-decayable base (component (D1)) is preferred because it is easy to improve the characteristics of high sensitivity, roughness reduction, and suppression of the occurrence of coating defects. Component (D1) and component (D2) may be in the form of compounds, incorporated into component (A1) as the above-mentioned constituent unit (a6), or in both forms. The compounds exemplified as component (D1) described later may be used as the acid-generating component (component (B)) mentioned above, depending on the combination with other compounds.

[0386] Regarding component (D1): Component (D1) is not particularly limited as long as it decomposes upon exposure and loses its acid diffusion controllability. Preferably, it is one or more compounds selected from the group consisting of the compound represented by the following general formula (d1-1) (hereinafter referred to as "component (d1-1)"), the compound represented by the following general formula (d1-2) (hereinafter referred to as "component (d1-2)"), and the compound represented by the following general formula (d1-3) (hereinafter referred to as "component (d1-3)"). Components (d1-1) to (d1-3) do not act as quenchers in the exposed areas of the resist film because they decompose and lose their acid diffusion controllability (basicity), but they act as quenchers in the unexposed areas of the resist film.

[0387] [In the formula, Rd １ ~Rd ４ Rd in formula (d1-2) is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. ２In this example, assume that no fluorine atoms are bonded to carbon atoms adjacent to the sulfur atom. １ is a single bond or a divalent linking group. m is an integer of 1 or more, and M ｍ＋ These are each independently m-valent organic cations.

[0388] {(d1-1) component} ... in the anionic component of formula (d1-1), Rd １ R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of the above R' is... ２０１ Similar examples include Rd １ Preferred substituents are optionally substituted aromatic hydrocarbon groups, optionally substituted aliphatic cyclic groups, or optionally substituted linear alkyl groups. Examples of substituents these groups may have include hydroxyl groups, oxo groups, alkyl groups, aryl groups, fluorine atoms, fluorinated alkyl groups, lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), ether bonds, ester bonds, or combinations thereof. When ether bonds or ester bonds are included as substituents, they may be mediated via alkylene groups, and in this case, preferred substituents are the linking groups represented by the general formulas (L-al-1) to (L-al-5). Note that Rd １ If the aromatic hydrocarbon group, aliphatic cyclic group, or linear alkyl group in has a linking group represented by the general formulas (L-al-1) to (L-al-7) as a substituent, then in the general formulas (L-al-1) to (L-al-7), Rd in formula (d1-1) １ The carbon atom constituting the aromatic hydrocarbon group, aliphatic cyclic group, or chain-like alkyl group in the above general formula (L-al-1) to (L-al-7) is V'. １０１ The aromatic hydrocarbon group can be preferably a phenyl group, a naphthyl group, or a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and other ring structures). The aliphatic cyclic group can be adamantane, norbornane, isobornane, or tricyclo[5.2.1.0 ２，６It is more preferable that the group is obtained by removing one or more hydrogen atoms from a polycycloalkane such as decane or tetracyclododecane. The chain-like alkyl group is preferably one to ten carbon atoms in number, and specifically, examples include linear alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, and decyl group; and branched alkyl groups such as 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

[0389] When the chain-like alkyl group is a fluorinated alkyl group having a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and even more preferably 1 to 4. The fluorinated alkyl group may contain atoms other than fluorine. Examples of atoms other than fluorine include oxygen atoms, sulfur atoms, nitrogen atoms, and the like.

[0390] The following are preferred specific examples of the anion portion of component (d1-1).

[0391]

[0392] ...In the cation component (d1-1), M ｍ＋ M is an organic cation with an m-valence. ｍ＋ Suitable organic cations include those similar to those represented by the general formulas (ca-1) to (ca-3), with the cation represented by the general formula (ca-1) being more preferred, and the cations represented by the formulas (ca-1-1) to (ca-1-84) being even more preferred. The (d1-1) component may be used alone or in combination of two or more types.

[0393] {(d1-2) component} ... in the anionic component of formula (d1-2), Rd ２R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. ２０１ Similar examples include the following. However, Rd ２ In this case, the carbon atom adjacent to the S atom is assumed to be unbonded to a fluorine atom (not fluorine-substituted). This results in the anions of components (d1-2) becoming appropriately weak acid anions, improving the quenching ability of component (D). Rd ２ Preferably, the group is a chain-like alkyl group which may have substituents, or an aliphatic cyclic group which may have substituents, and more preferably an aliphatic cyclic group which may have substituents.

[0394] The linear alkyl group is preferably having 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. The aliphatic cyclic group is adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ A group obtained by removing one or more hydrogen atoms from decane, tetracyclododecane, etc. (which may have substituents); more preferably a group obtained by removing one or more hydrogen atoms from camphor.

[0395] Rd ２ The hydrocarbon group may have substituents, and such substituents may be Rd of formula (d1-1). １ Examples include substituents similar to those that may be present on hydrocarbon groups (aromatic hydrocarbon groups, aliphatic cyclic groups, and linear alkyl groups) in the above.

[0396] The following are preferred specific examples of the anion portion of component (d1-2).

[0397]

[0398] ...In the cation component formula (d1-2), M ｍ＋ is an m-valent organic cation, and M in formula (d1-1) above. ｍ＋ The same applies. (d1-2) Components may be used individually or in combination of two or more.

[0399] {(d1-3) component} ... in the anionic component of formula (d1-3), Rd３ R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and the R' ２０１ Similar groups are mentioned, and it is preferable that they are cyclic groups containing a fluorine atom, linear alkyl groups, or linear alkenyl groups. Among these, fluorinated alkyl groups are preferred, and the aforementioned Rd １ A fluorinated alkyl group similar to the one shown is more preferable.

[0400] In formula (d1-3), Rd ４ R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. ２０１ Similar examples include alkyl groups, alkoxy groups, alkenyl groups, and cyclic groups, which may have substituents. Rd ４ The alkyl group in is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. ４ Some of the hydrogen atoms in the alkyl group may be substituted with hydroxyl groups, cyano groups, etc. Rd ４ The alkoxy group in is preferably an alkoxy group having 1 to 5 carbon atoms. Specifically, examples of alkoxy groups having 1 to 5 carbon atoms include methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, and tert-butoxy groups. Among these, methoxy and ethoxy groups are preferred.

[0401] Rd ４ The alkenyl group in R' is ２０１ Examples of groups similar to the alkenyl group in the above include vinyl groups, propenyl groups (allyl groups), 1-methylpropenyl groups, and 2-methylpropenyl groups, which are preferred. These groups may further have substituents of an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

[0402] Rd ４ The cyclic group in is R'２０１ Examples of cyclic groups similar to those in [5.2.1.0] include cyclopentane, cyclohexane, adamantane, norbornane, isobornane, and tricyclo[5.2.1.0]. ２，６ A preferred alicyclic group is obtained by removing one or more hydrogen atoms from a cycloalkane such as decane or tetracyclododecane, or an aromatic group such as a phenyl group or naphthyl group. ４ When Rd is an alicyclic group, the resist composition dissolves well in organic solvents, resulting in good lithography properties. ４ When the resist group is an aromatic group, in lithography using EUV or the like as the exposure light source, the resist composition exhibits excellent light absorption efficiency, resulting in good sensitivity and lithographic characteristics.

[0403] In formula (d1-3), Yd １ Yd is a single bond or a divalent linking group. １ The divalent linking group in formula (a2-1) is not particularly limited, but may include divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) which may have substituents, and divalent linking groups containing heteroatoms. ２１ Examples of divalent linking groups include divalent hydrocarbon groups that may have substituents, and divalent linking groups containing heteroatoms, as mentioned in the explanation of divalent linking groups in Yd. １ The preferred members are carbonyl groups, ester bonds, amide bonds, alkylene groups, or combinations thereof. The alkylene group is more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.

[0404] The following are preferred specific examples of the anionic portions of components (d1-3).

[0405]

[0406]

[0407] ...In the cation component formula (d1-3), M ｍ＋ is an m-valent organic cation, and M in formula (d1-1) above. ｍ＋The same applies. (d1-3) Components may be used individually or in combination of two or more.

[0408] The component (D1) may be any one of the above components (d1-1) to (d1-3), or two or more may be used in combination. When the resist composition contains component (D1), the content of component (D1) in the resist composition is preferably 0.5 to 15 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 15 parts by mass, per 100 parts by mass of component (A).

[0409] Component (D1) preferably contains component (d1-1) as described above. The content of component (d1-1) in the total component (D1) is preferably 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass or more, and component (D1) may consist only of compound (d1-1).

[0410] Method for producing component (D1): The method for producing components (d1-1) and (d1-2) described above is not particularly limited and can be produced by known methods. The method for producing component (d1-3) is also not particularly limited and can be produced, for example, in the same manner as described in US2012-0149916. As an example of a basic component (component (D)) that traps the acid generated by exposure, the compound of component (D1) is shown, but the compound of component (D1) may also be used as component (B). For example, in the resist composition of this embodiment, the compound of component (D1) may be used as component (B), and the compound that generates an acid with lower acidity than the acid generated by the compound of component (D1) upon exposure may be used as component (D). Alternatively, in the resist composition of this embodiment, the compound of component (D1) may be used as component (B), and the component (D2), described later, may be used as component (D).

[0411] Regarding component (D2): Component (D) may contain nitrogen-containing organic compound components that do not fall under component (D1) above (hereinafter referred to as "component (D2)"). Component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not fall under component (D1), and any known component may be used. Among these, aliphatic amines are preferred, and among these, secondary aliphatic amines and tertiary aliphatic amines are more preferred. An aliphatic amine is an amine having one or more aliphatic groups, and it is preferable that the aliphatic group has 1 to 12 carbon atoms. Examples of aliphatic amines include ammonia (NH) ３ Examples include amines (alkylamines or alkyl alcoholamines) or cyclic amines in which at least one hydrogen atom is substituted with an alkyl group or hydroxyalkyl group having 12 or fewer carbon atoms. Specific examples of alkylamines and alkyl alcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkyl alcoholamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 6 to 30 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine are particularly preferred.

[0412] Examples of cyclic amines include heterocyclic compounds containing a nitrogen atom as a heteroatom. These heterocyclic compounds may be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines). Specific examples of aliphatic monocyclic amines include piperidine and piperazine. Aliphatic polycyclic amines with 6 to 10 carbon atoms are preferred, and specific examples include 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo[2.2.2]octane.

[0413] 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, etc., with triethanolamine triacetate being preferred.

[0414] Furthermore, an aromatic amine may be used as component (D2). Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tripenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and 2,6-di-tert-butylpyridine.

[0415] The (D2) component may be used alone or in combination of two or more types. When the resist composition contains the (D2) component, the content of the (D2) component in the resist composition is usually in the range of 0.01 to 5 parts by mass per 100 parts by mass of the (A) component. By using the above range, the resist pattern shape, the stability over time, etc., are improved.

[0416] <<At least one compound (E) selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives>> The resist composition of this embodiment may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives (hereinafter referred to as "component (E)"). Specifically, examples of organic carboxylic acids include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, etc., with salicylic acid being preferred among them. Examples of phosphorus oxoacids include phosphoric acid, phosphonic acid, phosphinic acid, etc., with phosphonic acid being particularly preferred among these.

[0417] In the resist composition of this embodiment, component (E) may be used alone or in combination of two or more types. When the resist composition contains component (E), the content of component (E) is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass, per 100 parts by mass of component (A). By setting the content within the above range, the lithography characteristics are further improved.

[0418] ≪Fluorine Additive Component (F)≫ The resist composition of this embodiment may contain a fluorine additive component (hereinafter referred to as "component (F)") as a hydrophobic resin. Component (F) is used to impart water repellency to the resist film and, when used as a resin separate from component (A), can improve lithography properties. As component (F), for example, fluorine-containing polymer compounds described in Japanese Patent Publication No. 2010-002870, Japanese Patent Publication No. 2010-032994, Japanese Patent Publication No. 2010-277043, Japanese Patent Publication No. 2011-13569, and Japanese Patent Publication No. 2011-128226 can be used. More specifically as component (F), polymers having a constituent unit (f1) represented by the following general formula (f1-1) can be mentioned. The polymer is preferably a polymer (homopolymer) consisting only of a constituent unit (f1) represented by the following formula (f1-1); a copolymer of the constituent unit (f1) and the constituent unit (a1); and more preferably a copolymer of the constituent unit (f1) and a constituent unit derived from acrylic acid or methacrylic acid and the constituent unit (a1). Here, the constituent unit (a1) copolymerized with the constituent unit (f1) is preferably a constituent unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate, a constituent unit derived from 1-methyl-1-adamantyl (meth)acrylate, and more preferably a constituent unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate.

[0419] [In the formula, R is the same as above, Rf １０２ and Rf １０３ Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf １０２ and Rf １０３ They may be the same or different. １ Rf is an integer between 0 and 5. １０１ It is an organic group containing a fluorine atom.

[0420] In formula (f1-1), R bonded to the carbon atom at the α position is the same as described above. R is preferably a hydrogen atom or a methyl group. In formula (f1-1), Rf １０２ and Rf １０３ A fluorine atom is preferred as the halogen atom. Rf １０２ and Rf １０３ Examples of alkyl groups having 1 to 5 carbon atoms in R include those similar to the alkyl groups having 1 to 5 carbon atoms in R above, with methyl or ethyl groups being preferred. １０２ and Rf １０３ Specifically, examples of halogenated alkyl groups having 1 to 5 carbon atoms include groups in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Fluorine atoms are preferred as the halogen atoms, particularly Rf. １０２ and Rf １０３ Preferably, the atoms are hydrogen atoms, fluorine atoms, or alkyl groups having 1 to 5 carbon atoms; more preferably, hydrogen atoms, fluorine atoms, methyl groups, or ethyl groups; and even more preferably, hydrogen atoms. In formula (f1-1), nf １ x is an integer between 0 and 5, preferably between 0 and 3, and more preferably 1 or 2.

[0421] In formula (f1-1), Rf １０１ The fluorine atom is an organic group containing a fluorine atom, and 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, and particularly preferably 1 to 10 carbon atoms. Furthermore, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more, and particularly preferable that 60% or more are fluorinated, as this increases the hydrophobicity of the resist film during immersion exposure. Among these, Rf １０１ More preferably, it is a fluorinated hydrocarbon group having 1 to 6 carbon atoms, a trifluoromethyl group, or -CH ２ -CF ３ ien-CH ２ -CF２ -CF ３ , -CH(CF ３ ) ２ ien-CH ２ -CH ２ -CF ３ ien-CH ２ -CH ２ -CF ２ -CF ２ -CF ２ -CF ３ That is particularly preferable.

[0422] The weight-average molecular weight (Mw) of component (F) (based on polystyrene conversion by gel permeation chromatography) is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and most preferably 10,000 to 30,000. If it is below the upper limit of this range, it has sufficient solubility in the resist solvent for use as a resist, and if it is above the lower limit of this range, the water repellency of the resist film is good. The dispersion degree (Mw / Mn) of component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

[0423] In the resist composition of this embodiment, component (F) may be used alone or in combination of two or more types. When the resist composition contains component (F), the content of component (F) is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of component (A).

[0424] ≪Organic Solvent Component (S)≫ The resist composition of this embodiment can be manufactured by dissolving the resist material in an organic solvent component (hereinafter referred to as "component (S)"). In the resist composition of this embodiment, component (S) may be used alone or as a mixture of two or more solvents. Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), γ-butyrolactone, ethyl lactate (EL), and cyclohexanone are preferred.

[0425] Furthermore, a mixed solvent obtained by mixing PGMEA and a polar solvent is also preferred as component (S). The mixing ratio (mass ratio) can be appropriately determined considering the compatibility between PGMEA and the polar solvent. A mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferred as component (S). In this case, the mixing ratio is preferably 70:30 to 95:5 in mass ratio. The amount of component (S) used is not particularly limited and is appropriately set according to the coating thickness at a concentration that can be applied to a substrate, etc. Generally, 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.

[0426] The resist composition of this embodiment may be subjected to removal of impurities after dissolving the resist material in component (S), using a polyimide porous membrane, a polyamide-imide porous membrane, or the like. For example, the resist composition may be filtered using a filter made of a polyimide porous membrane, a filter made of a polyamide-imide porous membrane, or a filter made of a polyimide porous membrane and a polyamide-imide porous membrane. Examples of the polyimide porous membrane and the polyamide-imide porous membrane include those described in Japanese Patent Application Publication No. 2016-155121.

[0427] The resist composition of this embodiment described above contains a resin component having a constituent unit (a0) derived from a compound (a0-m) represented by the general formula (a0-m). The resist composition of this embodiment, by containing the constituent unit (a0), achieves high sensitivity, good lithography characteristics such as roughness, and excellent etching resistance. The reason for these effects is presumed to be as follows: In the constituent unit (a0), the introduction of a cyano group into the cation lowers the energy of the LUMO (Lowest Unoccupied Molecular Orbital) of the cation itself, making it easier to accept electrons. Therefore, in the resist composition of this embodiment, the decomposition of the cation is promoted during exposure, resulting in improved sensitivity equivalent to or better than cations having multiple electron-withdrawing groups, and improved roughness compared to cations having multiple electron-withdrawing groups due to increased affinity to the developer. In addition, the presence of a triple bond between carbon and nitrogen in the cyano group of the constituent unit (a0) improves the etching resistance of the resist composition of this embodiment. It is presumed that these effects work synergistically to improve sensitivity, roughness, and etching resistance in the resist composition of this embodiment.

[0428] (Method for forming a resist pattern) A method for forming a resist pattern according to a second aspect of the present invention is a method comprising the steps of forming a resist film on a support using the resist composition according to the first aspect of the present invention described above, exposing the resist film, and developing the exposed resist film to form a resist pattern. One embodiment of such a resist pattern forming method is, for example, a resist pattern forming method carried out as follows.

[0429] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and a bake (post-application bake (PAB)) treatment is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of, for example, 80 to 150°C, to form a resist film. Next, the resist film is subjected to selective exposure using an exposure apparatus such as an electron beam lithography apparatus or an ArF exposure apparatus, either through exposure via a mask (mask pattern) with a predetermined pattern formed on it or by direct irradiation with an electron beam without a mask pattern, and then a bake (post-exposure bake (PEB)) treatment is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of, for example, 80 to 150°C. Next, the resist film is subjected to a development treatment. In the case of an alkaline development process, an alkaline developer is used, and in the case of a solvent development process, a developer containing an organic solvent (organic developer) is used.

[0430] After development, rinsing is preferably performed. In the case of an alkaline development process, rinsing with pure water is preferred, and in the case of a solvent development process, rinsing with a rinsing solution containing an organic solvent is preferred. In the case of a solvent development process, after the development or rinsing process, the developer or rinsing solution adhering to the pattern may be removed using a supercritical fluid. After development or rinsing, drying is performed. In some cases, baking (post-baking) may be performed after the development process.

[0431] The support material is not particularly limited and can be any conventionally known material, such as a substrate for electronic components or a substrate on which a predetermined wiring pattern has been formed. More specifically, examples include silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, and glass substrates. As for the wiring pattern material, for example, copper, aluminum, nickel, and gold can be used.

[0432] The wavelength used for exposure is not particularly limited and can be an ArF excimer laser, KrF excimer laser, or F ２This can be carried out using radiation such as excimer lasers, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, and soft X-rays. The resist pattern formation method of this embodiment is particularly useful in the step of exposing the resist film to EUV (extreme ultraviolet) or EB (electron beam).

[0433] The method for exposing the resist film may be conventional exposure (dry exposure) performed in an inert gas such as air or nitrogen, or it may be liquid immersion lithography. Liquid immersion lithography is an exposure method in which the space between the resist film and the lens at the lowest position of the exposure apparatus is filled in advance with a solvent (liquid immersion medium) having a refractive index greater than that of air, and exposure (immersion exposure) is performed in that state. The liquid immersion medium is preferably a solvent having a refractive index greater than that of air and smaller than that of the resist film to be exposed, and examples include water, fluorine-based inert liquids, silicon-based solvents, hydrocarbon-based solvents, etc. Water is preferably used as the liquid immersion medium.

[0434] Examples of alkaline developers used in the alkaline development process include 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution. The organic solvent contained in the organic developer used in the solvent development process can be any solvent that can dissolve component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specifically, examples include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents.

[0435] Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butanoate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate.

[0436] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0437] Organic developers may contain known additives as needed. Examples of such additives include surfactants. While not particularly limited, surfactants such as ionic or nonionic fluorine-based and / or silicone-based surfactants can be used.

[0438] The development process can be carried out by known development methods, such as immersing the support in developer for a certain period of time (dip method), piling up developer on the surface of the support by surface tension and leaving it still for a certain period of time (paddle method), spraying developer onto the surface of the support (spray method), or continuously dispensing developer onto a support rotating at a constant speed while scanning the developer dispensing nozzle at a constant speed (dynamic dispensing method).

[0439] As the organic solvent contained in the rinsing solution used for rinsing after development in the solvent development process, for example, organic solvents that do not easily dissolve the resist pattern can be appropriately selected and used from among the organic solvents listed as organic solvents used in the organic developer solution. Typically, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents is used. These organic solvents may be used individually or in combination of two or more. They may also be used in mixture with other organic solvents or water.

[0440] Rinsing (cleaning) using a rinsing solution can be carried out by known rinsing methods. Examples of such rinsing methods include continuously applying the rinsing solution onto a support rotating at a constant speed (rotary coating method), immersing the support in the rinsing solution for a certain period of time (dip method), and spraying the rinsing solution onto the surface of the support (spray method).

[0441] According to the resist pattern formation method of this embodiment described above, since the above-mentioned resist composition is used, a resist pattern with good sensitivity, roughness, and etching resistance can be formed.

[0442] The resist compositions of the embodiments described above, and the various materials used in the pattern forming methods of the embodiments described above (for example, resist solvents, developers, rinse solutions, anti-reflective film forming compositions, topcoat forming compositions, etc.) are preferably free of impurities such as metals, metal salts containing halogens, acids, alkalis, sulfur atoms, or phosphorus atoms. Examples of metal atom-containing impurities include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The content of impurities in these materials is preferably 200 ppb or less, more preferably 1 ppb or less, even more preferably 100 ppt (parts per trillion) or less, particularly preferably 10 ppt or less, and most preferably substantially free (below the detection limit of the measuring device).

[0443] (Compound) The compound according to the third aspect of the present invention is a compound represented by the following general formula (a0-m) (hereinafter also referred to as "compound (a0-m)").

[0444] [In the formula, Ar ０１ Ar ０２ and Ar ０３ Each of these independently represents an aromatic ring. m01, m02, and m03 each independently represent an integer greater than or equal to 0, as far as the valence allows, and m01 + m02 + m03 ≥ 1. Rc ０１ , Rc ０２ , and Rc ０３ k01, k02, and k03 are each independent substituents other than cyano groups. k01, k02, and k03 each independently represent integers of 0 or greater, as long as the valency allows. If k01 is an integer of 2 or greater, then Rc is 2 or greater. ０１ They may be the same or different from each other. If k02 is an integer of 2 or more, then Rc must be 2 or more. ０２ They may be the same or different from each other. If k03 is an integer of 2 or more, then Rc must be 2 or more. ０３ They may be the same or different from each other. Z ０２ and Z ０３ Each of these independently represents a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ These bonds to each other, forming single bonds or divalent linking groups. ０ This represents a polymerizable group-containing group. ０ This represents a divalent linking group.

[0445] The compound of this embodiment is similar to the compound that derives the constituent unit (a0) of component (A1) of the resist composition according to the first embodiment.

[0446] <Method for Producing the Compound> Compound (a0-m) can be produced by appropriately combining known methods, as shown in the <Example of Compound Synthesis> in the [Examples] section below. For example, as shown in the (Example of Compound (a0-m-6)) below, compound (a0-m) can be produced by a salt exchange reaction between the chloride salt of the cation constituting the cation portion of compound (a0-m) and the ammonium salt of the anion constituting the anionic portion of compound (a0-m).

[0447] The temperature conditions for the salt exchange reaction are not particularly limited, but are, for example, around -10 to 120°C, preferably 0 to 100°C, and more preferably 10 to 70°C. The reaction time for the salt exchange reaction is not particularly limited, but is, for example, around 1 to 72 hours, and preferably 1 to 24 hours.

[0448] Examples of reaction solvents used in the aforementioned salt exchange reaction include dichloromethane, dichloroethane, chloroform, tetrahydrofuran, N,N-dimethylformamide, acetonitrile, propionitrile, N,N'-dimethylacetamide, and dimethyl sulfoxide.

[0449] The chloride salt of the cation constituting the cationic part of compound (a0-m), and the ammonium salt of the anion constituting the anionic part of compound (a0-m), can be produced by combining known methods, as shown in the <Examples of Compound Synthesis> section below. Sulfonium cations having a cyano group can be produced using aromatic ring compounds to which a cyano group has been introduced, as shown in the <Examples of Compound Synthesis> section.

[0450] In the method for producing compound (a0-m), after each reaction is completed, the compound in the reaction solution may be isolated and purified. Conventional known methods can be used for isolation and purification, and for example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography, etc., can be used in appropriate combinations. The structure of the compound obtained in the above manner is: １ H-nuclear magnetic resonance (NMR) spectroscopy, １３ It can be identified by common organic analysis methods such as C-NMR spectroscopy. The raw materials used in each step may be commercially available or synthesized.

[0451] The compounds of this embodiment described above can be used in the production of the resist composition according to the first embodiment. Furthermore, the compounds of this embodiment can be used in the production of the polymer compound according to the fourth embodiment, which will be described later.

[0452] (Polymer Compound) The polymer compound according to the fourth aspect of the present invention has a constituent unit (a0) represented by the general formula (a0-m). The constituent unit (a0) is the same as that described above. As a polymer compound according to the fourth aspect of the present invention, the polymer compounds represented by (A1-1) to (A1-36) above are good examples. The polymer compound of this embodiment can be used in the manufacture of the resist composition according to the first aspect described above. By including the polymer compound of this embodiment in the resist composition, sensitivity, roughness and etching resistance can be improved.

[0453] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0454] <Example of compound synthesis> (Example of compound (SO-7) synthesis) 64.9 g of 3-iodoanisole, 15.0 g of thionyl chloride, and 20.1 g of aluminum chloride were stirred in 519 g of dichloromethane under ice cooling for 2 hours. Then, the reaction mixture was added dropwise to cooled 2% hydrochloric acid and quenched, and the organic layer was washed four times with 300 g of water, and the solvent was removed from the organic layer by distillation. The obtained residue was recrystallized with acetonitrile to obtain 27.1 g of compound (SO-07).

[0455]

[0456] (Example of synthesis of compound (SO-8)) 20.0 g of compound (SO-07) was dissolved in 284 mL of anhydrous dichloromethane, and cooled to 0°C under a nitrogen atmosphere. 233 mL of boron tribromide dichloromethane solution (1 mol / L) was slowly added dropwise, and the mixture was stirred at 0°C for 2 hours. 900 mL of 30% aqueous ammonia was added to quench the mixture, and the organic layer was washed four times with 500 g of water. The solvent was then removed from the organic layer by distillation. The resulting residue was purified by silica gel column chromatography to obtain 16.5 g of compound (SO-8).

[0457]

[0458] (Example of synthesis of compound (SO-9)) 15.0 g of 3-methoxybenzenethiol, 11.4 g of 4-fluorobenzonitrile, and 14.2 g of potassium carbonate were stirred in 85 g of dimethylformamide (DMF) at room temperature for 5 hours. Then, 100 g of water and 100 g of TBME were added and stirred at room temperature, after which the organic layer was collected and the solvent was removed by distillation. 90 g of methanol was added to the obtained residue, and under ice cooling, 14.0 g of metachloroperbenzoic acid (mCPBA) was added and stirred at room temperature for 2 hours. 80 g of dichloromethane and 80 g of 5% sodium bicarbonate aqueous solution were added to the reaction mixture and stirred at room temperature, and the aqueous layer was removed. Then, the organic layer was washed twice with 80 g of 5% sodium thiosulfate aqueous solution and three times with 80 g of water, and the solvent was removed from the organic layer by distillation. The obtained residue was recrystallized with TBME to obtain 18.1 g of compound (SO-09).

[0459]

[0460] (Example of synthesis of compound (SO-10)) 15.0 g of compound (SO-09) was dissolved in 225 mL of acetic acid, and 19.4 g of iodine monochloride (ICl) was added dropwise. After heating to 80°C and stirring for 3 hours, the reaction mixture was added to water to precipitate a solid. The obtained solid was recrystallized with acetonitrile to obtain 20.8 g of compound (SO-10).

[0461]

[0462] (Example of synthesis of compound (C-6)) 15.0 g of compound (SO-1), 10.1 g of compound (d), and 21.3 g of trifluoromethanesulfonic acid anhydride were stirred in 150 g of dichloromethane at -20°C for 3 hours. 150 g of aqueous sodium bicarbonate solution was added and stirred at room temperature, after which the organic layer was recovered and the solvent was removed by distillation. The resulting residue was purified by silica gel column chromatography to obtain 23.8 g of compound (C-6).

[0463]

[0464] (Synthesis examples of compounds (C-1) to (C-3), (C-5), (C-7) to (C-13), (C-22) to (C-31), (C-33) to (C-35)) Compounds (C-1) to (C-3), (C-5), (C-7) to (C-13), (C-22) to (C-31), and (C-33) to (C-35) were synthesized in the same manner as described above (Synthesis example of compound (C-6)), except that one of compounds (SO-1) to (S-10) was used instead of compound (SO-01), and one of compounds (A) to (H) was used instead of compound (D).

[0465]

[0466]

[0467]

[0468]

[0469] (Synthesis examples of compounds (C-4), (C-36) to (C-39)) Compounds (C-4), (C-36) to (C-39) were synthesized in the same manner as the synthesis example of compound (SO-8), except that compounds (C-5) to (C-9) were used instead of compound (SO-7).

[0470]

[0471] (Example of synthesis of compound (C-15)) 13.0 g of compound (C-4), 7.1 g of compound (j), and 4.4 g of potassium carbonate were stirred in 55 g of DMF at 60°C for 4 hours. 100 g of water and 100 g of dichloromethane were added to the reaction mixture and stirred at room temperature, after which the aqueous layer was removed. The mixture was then washed three times with 100 g of water, and the solvent was removed from the organic layer by distillation. The resulting residue was purified by silica gel column chromatography to obtain 14.2 g of compound (C-15).

[0472]

[0473] (Synthesis examples of compounds (C-14), (C-16) to (C-21)) Compounds (C-14), (C-16) to (C-21) were synthesized in the same manner as described above (Synthesis example of compound (C-15)), except that one of compounds (C-34) to (C-39) was used instead of compound (C-4), and compound (j) or compound (k) was used instead of compound (j).

[0474]

[0475]

[0476] (Example of synthesis of compound (a0-m-6)) 15.0 g of compound (C-6) was mixed with 150 g of dichloromethane, 26.7 g of compound (I), and 100 g of water, and the mixture was stirred at room temperature. The organic layer was collected, washed repeatedly with water, the solvent was removed by distillation, and the mixture was dried to obtain 29.7 g of compound (a0-m-6).

[0477]

[0478] (Synthesis examples of compounds (a0-m-1) to (a0-m-5) and (a0-m-7) to (a0-m-36)) Compounds (a0-m-1) to (a0-m-5) and (a0-m-7) to (a0-m-36) were synthesized from compounds (C-1) to (C-3), (C-5), (C-7) to (C-31), (C-35), and (C-37) and compounds (I) to (VI), respectively, in the same manner as in the synthesis example of compound (a0-m-6).

[0479]

[0480]

[0481]

[0482]

[0483]

[0484] The structures of the obtained compounds (a0-m-1) to (a0-m-36) were confirmed by measuring the molecular ion peaks (m / z) using electrospray ionization (ESI) mass spectrometry (Waters ACQUITY UPLC H-Class / SQD system). The results are shown in Tables 1 and 2 below. The values ​​in Tables 1 and 2 represent the m / z values ​​of the cation portion and the anion portion of (a0-m-1) to (a0-m-36).

[0485]

[0486]

[0487] <Preparation of Polymer Compound> (Synthesis of Polymer Compound (A1-1)) A dropwise solution was prepared by dissolving 25.0 g of compound (a0-m-1), 8.4 g of compound (a10-m-pre1), 19.4 g of compound (a1-m-1), and 3.9 g of azobis(isobutyrate)dimethyl (V-601) as a polymerization initiator in 31.0 g of methyl ethyl ketone (MEK). 27.4 g of MEK was added to a three-necked flask connected to a thermometer, reflux condenser, and nitrogen inlet tube, and the mixture was heated to 85°C under a nitrogen atmosphere. The dropwise solution was then added dropwise over 4 hours. After the dropwise addition was complete, the reaction mixture was stirred at 85°C for 1 hour. The reaction mixture was then cooled to room temperature. After the reaction was complete, the resulting reaction mixture was precipitated with 100 g of heptane, and the precipitate was washed. The resulting white solid was filtered and dried under reduced pressure overnight to obtain polymer compound (A1-1).

[0488]

[0489] (Synthesis of polymer compounds (A1-2) to (A1-36)) Polymer compounds (A1-2) to (A1-36) were synthesized in the same manner as the synthesis of polymer compound (A1-1), except that the compound used in the polymerization reaction was changed.

[0490] Polymer compounds (A1-1) to (A1-36) are shown below. In the following formulas, l, m, and n represent the composition ratio (molar ratio) of each constituent unit.

[0491]

[0492]

[0493]

[0494]

[0495]

[0496] (Synthesis of polymer compounds (A2-1) to (A2-5)) Polymer compounds (A2-1) to (A2-5) were synthesized in the same manner as the synthesis of polymer compound (A1-1), except that the compound used in the polymerization reaction was changed.

[0497] Polymer compounds (A2-1) to (A2-5) are shown below. In the formulas below, l, m, and n represent the composition ratio (molar ratio) of each constituent unit.

[0498]

[0499] For the obtained polymer compounds (A1-1) to (A1-36) and (A2-1) to (A2-5), the weight-average molecular weight (Mw) and molecular weight dispersion (Mw / Mn) were determined by GPC measurement (standard polystyrene equivalent). Furthermore, for the polymer compounds (A1-1) to (A1-36) and (A2-1) to (A2-5), the copolymerization composition ratio (proportion of each constituent unit in the structural formula (molar ratio)) was determined by carbon-13 nuclear magnetic resonance spectroscopy (600 MHz, １３ The results were obtained by C-NMR. The results are shown in Tables 3 to 5 below.

[0500]

[0501]

[0502]

[0503]

[0504] <Preparation of Resist Compositions> (Examples 1-37, Comparative Examples 1-5) The resist compositions for each example were prepared by mixing and dissolving the components shown in Tables 6-8.

[0505]

[0506]

[0507]

[0508] In Tables 6 to 8, each abbreviation has the following meaning. The numbers in brackets [ ] represent the amount (parts by mass) of each compound. (A1-1) to (A1-36): The above polymer compounds (A1-1) to (A1-36) (A2-1) to (A2-5): The above polymer compounds (A2-1) to (A2-5)

[0509] (B1-1): An acid generator consisting of the following compound (B1-1).

[0510]

[0511] (D1-1) to (D1-2): Acid diffusion control agents consisting of compounds represented by the following chemical formulas (D1-1) to (D1-2).

[0512]

[0513] (S-1): A mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 / 40 (mass ratio).

[0514] <Formation of Resist Pattern> Steps for forming the resist film: Each resist composition was applied to an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS) using a spinner, and a pre-bake (PAB) treatment was performed on a hot plate at a temperature of 110°C for 60 seconds, followed by drying to form a resist film with a thickness of 50 nm.

[0515] Steps for exposing the resist film: Next, the resist film was exposed using an electron beam lithography system JEOL JBX-9300FS (manufactured by JEOL Ltd.) at an acceleration voltage of 100 kV, with a target size of a 1:1 line-and-space pattern (hereinafter referred to as "LS pattern") with a line width of 25 nm (pitch width of 50 nm). After that, a post-exposure heating (PEB) treatment was performed at 100°C for 60 seconds.

[0516] Steps for developing the resist film after exposure: Next, alkaline development was performed at 23°C for 60 seconds using a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.). After that, a water rinse was performed with pure water for 15 seconds. As a result, a 1:1 LS pattern with a line width of 25 nm was formed.

[0517] [Evaluation of Optimal Exposure Dose (Eop)] The optimal exposure dose Eop (μC / cm²) for forming a target-sized LS pattern through the above <Formation of Resist Pattern> process. ２ We calculated this as "Eop(μC / cm²)". ２ These are shown in Tables 9-11.

[0518] [Evaluation of LWR (Line-Wide Roughness)] For the LS pattern formed in the above <Formation of Resist Pattern>, 3σ, a measure of LWR, was determined. This is shown as "LWR (nm)" in Tables 9 to 11. "3σ" represents three times the standard deviation (σ) (unit: nm) obtained from the measurement results of 400 line positions measured in the longitudinal direction of the line using a scanning electron microscope (acceleration voltage 800V, product name: S-9380, manufactured by Hitachi High-Technologies Corporation). A smaller value of 3σ means that the roughness of the line sidewall is smaller and a more uniform width LS pattern was obtained.

[0519] [Evaluation of Etching Resistance] Each resist composition was applied to an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS) using a spinner. A pre-bake (PAB) treatment was performed on a hot plate at 110°C for 60 seconds, and then dried to form a resist film with a thickness of 50 nm. Next, each resist film was subjected to CF etching using a dry etching apparatus TCA-3822 (product name, manufactured by Tokyo Ohka Kogyo Co., Ltd.). ４ Dry etching was performed using gas for 60 seconds. The amount of residual film was determined from the thickness of the resist film before and after the dry etching. The amount of residual film formed using each example's resist composition was then calculated as a relative value, with the amount of residual film formed using Comparative Example 1's resist composition set to 1. The results are shown in Tables 9 to 11 as "etching resistance". A higher "etching resistance" value indicates higher etching resistance of the resist film.

[0520]

[0521]

[0522]

[0523] As shown in Tables 9 to 11, the resist compositions of Examples 1 to 37 were found to have better sensitivity, roughness, and etching resistance compared to the resist compositions of Comparative Examples 1 to 5.

[0524] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications to the configuration are possible without departing from the spirit of the present invention. The present invention is not limited by the foregoing description and is limited only by the appended claims.

Claims

1. A resist composition that generates an acid upon exposure, and whose solubility in a developer changes under the action of the acid, the resist composition comprising a resin component (A1) whose solubility in a developer changes under the action of the acid, wherein the resin component (A1) has a structural unit (a0) derived from a compound represented by general formula (a0-m) shown below. [In the formula, Ar ０１ , Ar ０２ and Ar ０３ each independently represent an aromatic ring. m01, m02 and m03 each independently represent an integer of 0 or more as long as the valency allows, and m01+m02+m03≧1. Rc ０１ , Rc ０２ , and Rc ０３ each independently represent a substituent other than a cyano group. k01, k02 and k03 each independently represent an integer of 0 or more as long as the valency allows. When k01 is an integer of 2 or more, 2 or more of Rc ０１ may be the same as or different from each other. When k02 is an integer of 2 or more, 2 or more of Rc ０２ may be the same as or different from each other. When k03 is an integer of 2 or more, 2 or more of Rc ０３ may be the same as or different from each other. Z ０２ and Z ０３ each independently represent a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ are bonded to each other to form a single bond or a divalent linking group. W ０ represents a polymerizable group-containing group. Y ０ represents a divalent linking group.] 2. The resist composition according to claim 1, wherein in the general formula (a0-m), m01 + m02 + m03 ≥ 2.

3. In the above general formula (a0-m), Rc ０１ , Rc ０２ , and Rc ０３ The resist composition according to claim 1, wherein at least one of the groups is an electron-withdrawing group other than a cyano group.

4. In the above general formula (a0-m), Rc ０１ , Rc ０２ , and Rc ０３ The resist composition according to claim 1, wherein at least one of the groups is an acid-degradable group.

5. The resist composition according to claim 1, wherein the constituent unit (a0) is a constituent unit derived from a compound represented by the following general formula (a0-m1), or a constituent unit derived from a compound represented by the following general formula (a0-m2). [In the formula, Ar ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ k01, k02, and k03 are, respectively, Ar in the general formula (a0-m). ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ , is identical to k01, k02, and k03. R １０ａ This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La １０ａ This is a divalent linking group or a single bond. Ra １０ａ n is a divalent hydrocarbon group which may have substituents. １０ａ It is an integer between 0 and 2. １１ａ It is a divalent linking group. １０ａ Rf is a divalent linking group or a single bond. １０ａ It is a divalent linking group containing a fluorine atom. [In the formula, Ar ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ k01, k02, and k03 are, respectively, Ar in the general formula (a0-m). ０１ Ar ０２ Ar ０３ , m01, m02, m03, Rc ０１ , Rc ０２ , Rc ０３ , is identical to k01, k02, and k03. R ２０ａ and R ２１ａ Each of these is independently an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La ２０ａ This is a divalent linking group or a single bond. ２０ａ Rf is a divalent linking group. ２０ａ It is a divalent linking group containing a fluorine atom.

6. A method for forming a resist pattern, comprising the steps of: forming a resist film on a support using the resist composition described in claim 1; exposing the resist film; and developing the exposed resist film to form a resist pattern.

7. A compound represented by the following general formula (a0-m). [In the formula, Ar ０１ Ar ０２ and Ar ０３ Each of these independently represents an aromatic ring. —m01, m02, and m03 each independently represent an integer greater than or equal to 0, as far as the valence allows, and m01 + m02 + m03 ≥ 1. Rc ０１ , Rc ０２ , and Rc ０３ k01, k02, and k03 are each independent substituents other than cyano groups. k01, k02, and k03 each independently represent integers of 0 or greater, as long as the valency allows. If k01 is an integer of 2 or greater, then Rc is 2 or greater. ０１ They may be the same or different from each other. If k02 is an integer greater than or equal to 2, then Rc must be greater than or equal to 2. ０２ They may be the same or different from each other. If k03 is an integer of 2 or more, then Rc must be 2 or more. ０３ They may be the same or different from each other. Z ０２ and Z ０３ Each of these independently represents a substituent other than a cyano group or a hydrogen atom, or Z ０２ and Z ０３ These bonds to each other, forming single bonds or divalent linking groups. ０ This represents a polymerizable group-containing group. ０ This represents a divalent linking group.

8. A polymer compound having a structural unit derived from the compound described in claim 7.

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