Inhibitor composition, inhibitor pattern formation method, compound and acid generating agent

Abstract

This invention relates to a resist composition comprising a substrate component (A) and a compound (B0) represented by a general formula (b0). Wherein, Ar 0 is an exynyl or hetero-exynyl, R m1 and R m2 is a substituent other than the iodine atom. L 01 represents a divalent linker or a single bond, L 02 is a divalent linked base, Vb 0 represents a single bond, etc. R 0 represents hydrogen atoms, etc. nb1 is an integer from 2 to 4, nb2 is an integer from 1 to 3, nb3 is an integer from 0 to 2, nb4 is an integer greater than 0, nb5 is an integer greater than 1, M m+ represents an m-valent organic cation, where m is an integer greater than or equal to 1.

Description

Technical Field

[0001] The present invention relates to a resist composition, a resist pattern forming method, a compound and an acid generator. This case claims priority of Special Application No. 2022-027098 filed in Japan on February 24, 2022, and adopts its content. Prior Art

[0002] In recent years, advancements in lithography have led to a rapid evolution in the miniaturization of patterns in the manufacture of semiconductor devices and liquid crystal displays. A common approach to miniaturization is to use shorter wavelengths (higher energy) of the exposure light source.

[0003] Resist materials are required to have lithographic properties such as sensitivity to such exposure light sources and resolution capable of reproducing fine-sized patterns. As a resist material that meets such requirements, a chemically amplified resist composition containing a base component whose solubility in a developer changes due to the action of an acid and an acid generator component that generates an acid due to exposure has been used in the past.

[0004] For example, Patent Document 1 discloses a resist composition containing a resin component having specific three structural units and a known onium salt acid generator. This resist composition inhibits acid diffusion, enhances affinity for developer, and improves sensitivity, roughness reduction, and resolution. [Prior Art Literature] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2020-085916 Summary of the Invention

[0006] [Problems to be Solved by the Present Invention]

[0007] With the advancement of lithography technology and the expansion of its application areas, the miniaturization of patterns has rapidly evolved. Furthermore, in the manufacture of semiconductor devices, there is a growing demand for technologies that can form fine patterns with good shapes. However, in the conventional resist composition described in Patent Document 1, the compatibility between sensitivity and roughness reduction during resist pattern formation is insufficient, and a higher level of compatibility is required. Furthermore, from the perspective of further improving sensitivity and reducing roughness, there is still room for research on the acid generator component.

[0008] In view of the above facts, the present invention aims to provide a resist composition that pursues high sensitivity and can form a resist pattern with good roughness reduction, a resist pattern forming method using the resist composition, a novel compound that is useful as an acid generator for the resist composition, and an acid generator using the compound. [Methods for solving the problem]

[0009] In order to solve the above-mentioned problems, the present invention adopts the following structure. That is, the first aspect of the present invention is a resist composition that generates acid upon exposure and changes its solubility in a developer due to the action of the acid, and comprises: The base material component (A) whose solubility in the developer changes due to the action of acid, Acid generator component (B) that generates acid due to exposure, The acid generator component (B) comprises a compound (B0) represented by the following general formula (b0):

[0010] [wherein, Ar0 is an arylene group or a heteroarylene group, Rm1 and Rm2 are each independently a substituent other than an iodine atom, L01 is a divalent linking group or a single bond, L02 is a divalent linking group, Vb0 is a single bond, an alkylene group or a fluorinated alkylene group, R0 is a hydrogen atom, a fluorinated alkylene group having 1 to 5 carbon atoms, or a fluorine atom, nb1 is an integer of 2 to 4, nb2 is an integer of 1 to 3, nb3 is an integer of 0 to 2, nb4 is an integer of 0 or greater, nb5 is an integer of 1 or greater, Mm+ represents an m-valent organic cation, and m is an integer of 1 or greater].

[0011] The second aspect of the present invention is a resist pattern forming method comprising: The step of forming a resist film on a support using the resist composition related to the first type mentioned above, The step of exposing the resist film, and The step of developing the above-mentioned exposed resist film to form a resist pattern.

[0012] The third embodiment of the present invention is a compound represented by the above general formula (b0).

[0013] The fourth aspect of the present invention is an acid generator comprising the compound related to the third aspect of the present invention. [Effects of the Invention]

[0014] The present invention provides a resist composition that pursues high sensitivity and can form a resist pattern with good roughness reduction, a resist pattern forming method using the resist composition, a novel compound that is useful as an acid generator for the resist composition, and an acid generator using the compound. Implementation Method

[0015] In this specification and the scope of this patent application, "aliphatic" is defined as a concept relative to aromatic and refers to groups, compounds, etc. that do not have aromatic properties. Unless otherwise specified, "alkyl" includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group. Unless otherwise specified, "alkylene" includes linear, branched, and cyclic divalent saturated hydrocarbon groups. Examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. The term "constituent unit" refers to a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer). When it is stated that "may have a substituent", this includes both the case where a hydrogen atom (-H) is replaced by a monovalent group and the case where a methylene group (-CH2-) is replaced by a divalent group. The concept of "exposure" includes all exposure to radiation.

[0016] The "acid-decomposable group" is an acid-decomposable group in which at least a portion of the bonds in the structure of the acid-decomposable group can be cleaved by the action of an acid. Examples of acid-decomposable groups whose polarity increases due to the action of an acid include groups that decompose due to the action of an acid to generate a polar group. Examples of the polar group include a carboxyl group, a hydroxyl group, an amino group, and a sulfonic acid group (—SO 3H). More specifically, examples of the acid-decomposable group include groups in which the aforementioned polar groups are protected by an acid-decomposable group (for example, groups in which the hydrogen atoms of polar groups containing OH are protected by an acid-decomposable group).

[0017] "Acid-dissociable group" means (i) a group capable of cleaving the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by the action of an acid, or (ii) a group capable of cleaving the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by producing a decarbonation reaction after a portion of the bond is cleaved by the action of an acid. The acid-dissociable group that constitutes the acid-decomposable group must be a group with a lower polarity than the polar group generated by the dissociation of the acid-dissociable group. Therefore, when the acid-dissociable group dissociates due to the action of the acid, a polar group with a higher polarity than the acid-dissociable group is generated, increasing the polarity. As a result, the polarity of the entire component (A1) increases. This increase in polarity also causes a corresponding change in solubility in the developer: alkaline developers increase solubility, while organic developers decrease solubility.

[0018] "Base component" refers to an organic compound with film-forming properties. Organic compounds used as base components are broadly categorized into non-polymers and polymers. Non-polymers generally have a molecular weight of 500 to 4000. "Low molecular weight compounds" are non-polymers with a molecular weight of 500 to 4000. Polymers generally have a molecular weight of 1000 or greater. "Resins," "high molecular weight compounds," or "polymers" are polymers with a molecular weight of 1000 or greater. The molecular weight of polymers is the weight average molecular weight calculated as polystyrene by GPC (gel permeation chromatography).

[0019] "Derived structural units" refer to structural units formed by cleavage of multiple bonds between carbon atoms, such as ethylene double bonds. In "acrylates," the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent. The substituent (R αx) replacing the hydrogen atom bonded to the α-carbon atom is an atom or group other than a hydrogen atom. This also includes itaconate diesters in which the substituent (R αx) is substituted with a substituent containing an ester bond, or α-hydroxyacrylates in which the substituent (R αx) is substituted with a hydroxyalkyl group or a group modifying the hydroxyl group. Furthermore, the α-carbon atom of an acrylate, unless otherwise specified, refers to the carbon atom to which the carbonyl group of the acrylic acid is bonded. Hereinafter, an acrylate in which the hydrogen atom bonded to the α-carbon atom is substituted with a substituent may be referred to as an α-substituted acrylate.

[0020] The term "derivative" encompasses compounds in which the α-position hydrogen atom of the target compound is replaced with an alkyl group, alkyl halide, or other substituent, as well as derivatives thereof. Examples of such derivatives include compounds in which the α-position hydrogen atom of a hydroxyl group of the target compound (where the α-position hydrogen atom may be substituted with a substituent) is replaced with an organic group, and compounds in which a substituent other than a hydroxyl group is bonded to the target compound (where the α-position hydrogen atom may be substituted with a substituent). Unless otherwise specified, the α-position refers to the first carbon atom adjacent to the functional group. As the substituent for the α-hydrogen atom of the hydroxystyrene, there can be mentioned the same substituents as for R αx.

[0021] In this specification and the scope of the patent application, depending on the structure represented by the chemical formula, there may be asymmetric carbons, and enantiomers or diastereomers may exist. In this case, these isomers are represented by a single chemical formula. These isomers may be used alone or as a mixture.

[0022] (Resistant composition) The resist composition of this embodiment generates acid upon exposure, and the solubility in the developer changes due to the action of the acid. The resist composition includes a base component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer changes due to the action of an acid, and an acid generator component (B) that generates acid upon exposure.

[0023] When a resist film is formed using the resist composition of this embodiment and selectively exposed, acid is generated from component (B) in the exposed portions of the resist film. This acidic action changes the solubility of component (A) in the developer. On the other hand, the solubility of component (A) in the developer remains unchanged in the unexposed portions of the resist film, resulting in a difference in solubility in the developer between the exposed and unexposed portions. Consequently, when the resist film is developed, if the resist composition is positive-working, the exposed portions of the resist film are dissolved and removed, forming a positive-working resist pattern. If the resist composition is negative-working, the unexposed portions of the resist film are dissolved and removed, forming a negative-working resist pattern.

[0024] The resist composition of this embodiment can be either a positive-tone resist composition or a negative-tone resist composition. Furthermore, the resist composition of this embodiment can be used in an alkali development process using an alkali developer during the development process for resist pattern formation, or in a solvent development process using a developer containing an organic solvent (organic developer).

[0025] <(A)Component> In the resist composition of this embodiment, component (A) preferably includes a resin component (A1) (hereinafter also referred to as "component (A1)") whose solubility in the developer changes due to the action of an acid. By using component (A1), since the polarity of the substrate components changes before and after exposure, good development contrast can be obtained not only in an alkali development process but also in a solvent development process. As the component (A), other high molecular weight compounds and / or low molecular weight compounds may be used in combination with the component (A1). Component (A) may also be a "base component that generates an acid upon exposure and changes its solubility in the developer due to the action of the acid." When component (A) is a base component that generates an acid upon exposure and changes its solubility in the developer due to the action of the acid, component (A1) is preferably a resin that generates an acid upon exposure and changes its solubility in the developer due to the action of the acid. Such a resin can be a polymer compound having a structural unit that generates an acid upon exposure. Known structural units that generate an acid upon exposure can be used.

[0026] In the resist composition of this embodiment, the component (A) may be used alone or in combination of two or more.

[0027] ･About (A1) ingredients The component (A1) is a resin component whose solubility in the developer changes due to the action of an acid. The component (A1) is preferably one having a structural unit (a1) containing an acid-decomposable group whose polarity increases due to the action of an acid. The component (A1) may have other structural units in addition to the structural unit (a1) as needed.

[0028] Constituent unit (a1) The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity increases due to the action of an acid.

[0029] As the acid-dissociable group, there is proposed an acid-dissociable group as a base resin for a chemically amplified resist composition. Specifically, the acid-dissociable groups proposed as base resins for chemically amplified resist compositions include the "acetal-type acid-dissociable group," the "tertiary alkyl ester-type acid-dissociable group," the "tertiary alkyloxycarbonyl acid-dissociable group," and the "secondary alkyloxycarbonyl acid-dissociable group" described below.

[0030] Acetal type acid dissociative group: Among the aforementioned polar groups, examples of acid-dissociable groups that serve as carboxyl groups or protected hydroxyl groups include acid-dissociable groups represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as "acetal-type acid-dissociable groups").

[0031] [In the formula, Ra'1 and Ra'2 are hydrogen atoms or alkyl groups. Ra'3 is a hydrocarbon group, and Ra'3 may also be bonded to either Ra'1 or Ra'2 to form a ring.]

[0032] In formula (a1-r-1), it is preferred that at least one of Ra'1 and Ra'2 is a hydrogen atom, and it is even more preferred that both are hydrogen atoms. When Ra'1 or Ra'2 is an alkyl group, the alkyl group may be the same as the alkyl group exemplified as the substituent that may be bonded to the α-position carbon atom in the description of the α-substituted acrylate. Alkyl groups having 1 to 5 carbon atoms are preferred. Specifically, linear or branched alkyl groups are preferred. More specifically, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups are preferred. Methyl or ethyl groups are more preferred, and methyl groups are particularly preferred.

[0033] In formula (a1-r-1), the hydrocarbon group of Ra' 3 includes a linear or branched alkyl group, or a cyclic hydrocarbon group. The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl, ethyl, n-propyl, n-butyl, and n-pentyl groups. Among these, methyl, ethyl, or n-butyl groups are preferred, and methyl or ethyl groups are even more preferred.

[0034] The branched chain alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples include isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl, 1,1-diethylpropyl, and 2,2-dimethylbutyl, with isopropyl being preferred.

[0035] When Ra'3 is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. The aliphatic hydrocarbon group as the monocyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group as the polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane. The polycycloalkane is preferably one having 7 to 12 carbon atoms. Specifically, adamantane, Alkane, Iso Alkane, tricyclodecane, tetracyclododecane, etc.

[0036] When the cyclic hydrocarbon group of Ra' 3 is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system with 4n+2 π electrons and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aforementioned aromatic hydrocarbon rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocyclic rings include oxygen, sulfur, and nitrogen atoms. Specific examples of aromatic heterocyclic rings include pyridine and thiophene rings. Specific examples of the aromatic hydrocarbon group in Ra'3 include groups obtained by removing one hydrogen atom from the aforementioned aromatic hydrocarbon ring or aromatic heterocycle (aryl or heteroaryl groups); groups obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene); and groups obtained by replacing one hydrogen atom of the aforementioned aromatic hydrocarbon ring or aromatic heterocycle with an alkylene group (e.g., arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, and 2-naphthylethyl). The alkylene group bonded to the aforementioned aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0037] The cyclic hydrocarbon group in Ra'3 may also have a substituent. Examples of such substituents include the above-mentioned Rax5.

[0038] When Ra'3 is bonded to either Ra'1 or Ra'2 to form a ring, the cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include tetrahydropyranyl and tetrahydrofuranyl.

[0039] Tertiary alkyl ester type acid dissociative group: Among the above polar groups, examples of acid-dissociable groups for protecting carboxyl groups include acid-dissociable groups represented by the following general formula (a1-r-2). Furthermore, among the acid-dissociable groups represented by the following formula (a1-r-2), those composed of an alkyl group are sometimes referred to as "tertiary alkyl ester type acid-dissociable groups" for convenience.

[0040] [In the formula, Ra'4 to Ra'6 are each a hydrocarbon group, and Ra'5 and Ra'6 may be bonded to each other to form a ring.]

[0041] Examples of the hydrocarbon group of Ra'4 include a linear or branched alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group. Examples of the linear or branched alkyl group and cyclic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group, aromatic hydrocarbon group) in Ra'4 include the same ones as those in Ra'3 above. The chain or cyclic alkenyl group in Ra' 4 is preferably an alkenyl group having 2 to 10 carbon atoms. Examples of the hydrocarbon groups of Ra'5 and Ra'6 include the same ones as those mentioned above for Ra'3.

[0042] When Ra'5 and Ra'6 are bonded to each other to form a ring, suitable examples include a group represented by the following general formula (a1-r2-1), a group represented by the following general formula (a1-r2-2), and a group represented by the following general formula (a1-r2-3). On the other hand, when Ra'4 to Ra'6 are not bonded to each other and are independent hydrocarbon groups, groups represented by the following general formula (a1-r2-4) are suitable examples.

[0043] [In formula (a1-r2-1), Ra'10 represents a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with a halogen atom or a heteroatom-containing group. Ra'11 is a group that forms an aliphatic cyclic group together with the carbon atom to which Ra'10 is bonded. In formula (a1-r2-2), Ya is a carbon atom, and 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. Ra101 to Ra103 are each independently a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms in these chain saturated hydrocarbon groups and aliphatic cyclic saturated hydrocarbon groups may be substituted. Two or more of Ra101 to Ra103 may be bonded 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 that may have a substituent. In formula (a1-r2-4), Ra' 12 and Ra' 13 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain saturated hydrocarbon group may be substituted. Ra' 14 is a hydrocarbon group that may have a substituent. * indicates a bonding site (the same applies hereinafter).

[0044] In the above formula (a1-r2-1), Ra' 10 is a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with a halogen atom or a heteroatom-containing group.

[0045] The linear alkyl group in Ra'10 has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. Examples of the branched chain alkyl group in Ra'10 include the same ones as those in Ra'3 described above.

[0046] The alkyl group in Ra' 10 may be partially substituted with a halogen atom or a heteroatom-containing group. For example, a portion of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. Furthermore, a portion of the carbon atoms (such as a methylene group) constituting the alkyl group may be substituted with a heteroatom-containing group. Examples of heteroatoms include oxygen, sulfur, and nitrogen atoms. Examples of heteroatom-containing groups include (-O-), -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -S-, -S(=O) 2-, and -S(=O) 2-O-.

[0047] In formula (a1-r2-1), Ra'11 (the aliphatic cyclic group formed simultaneously with the carbon atom to which Ra'10 is bonded) is preferably any of the groups listed as the monocyclic or polycyclic aliphatic hydrocarbon groups (alicyclic hydrocarbon groups) of Ra'3 in formula (a1-r-1). Among them, monocyclic alicyclic hydrocarbon groups are preferred, and more specifically, cyclopentyl and cyclohexyl groups are more preferred.

[0048] In formula (a1-r2-2), examples of the cyclic hydrocarbon group formed together with Xa and Ya include groups obtained by removing one or more hydrogen atoms from a cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) in Ra'3 in the aforementioned formula (a1-r-1). The cyclic hydrocarbon group formed by Xa and Ya together may also have a substituent. Examples of such substituents include the same substituents as those that may be possessed by the cyclic hydrocarbon group in Ra' 3 described above. In formula (a1-r2-2), examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra 101 to Ra 103 include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl. In Ra 101 to Ra 103, examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl; and polycyclic aliphatic saturated hydrocarbon groups such as bicyclo[2.2.2]octyl, tricyclo[5.2.1.02,6]decyl, tricyclo[3.3.1.13,7]decyl, tetracyclo[6.2.1.13,6.02,7]dodecyl, and adamantyl. Among Ra 101 to Ra 103, from the viewpoint of ease of synthesis, a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms is preferred, among which a hydrogen atom, a methyl group, and an ethyl group are more preferred, and a hydrogen atom is particularly preferred.

[0049] Examples of the substituents possessed by the chain saturated hydrocarbon group or aliphatic cyclic saturated hydrocarbon group represented by Ra 101 to Ra 103 include the same substituents as those for Ra x5 above.

[0050] Examples of groups containing a carbon-carbon double bond formed by two or more of Ra 101 to Ra 103 bonding to form a cyclic structure include cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, cyclopentylidenevinyl, and cyclohexylidenevinyl. Among these, cyclopentenyl, cyclohexenyl, and cyclopentylidenevinyl are preferred from the perspective of ease of synthesis.

[0051] In formula (a1-r2-3), the aliphatic cyclic group formed together with Xaa and Yaa is preferably the aliphatic hydrocarbon group listed as the monocyclic group or polycyclic group of Ra'3 in formula (a1-r-1). In formula (a1-r2-3), the aromatic hydrocarbon group in Ra 104 includes groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among these, Ra 104 is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or phenanthrene, even more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, or anthracene, particularly preferably a group obtained by removing one or more hydrogen atoms from benzene or naphthalene, and most preferably a group obtained by removing one or more hydrogen atoms from benzene.

[0052] Examples of substituents that Ra 104 in formula (a1-r2-3) may have include a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom, an alkoxy group (methoxy, ethoxy, propoxy, butoxy, etc.), and an alkyloxycarbonyl group.

[0053] In formula (a1-r2-4), Ra'12 and Ra'13 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms. Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra'12 and Ra'13 include the same monovalent chain saturated hydrocarbon groups having 1 to 10 carbon atoms as those described above for Ra'101 to Ra'103. Some or all of the hydrogen atoms in these chain saturated hydrocarbon groups may be substituted. Among Ra' 12 and Ra' 13, an alkyl group having 1 to 5 carbon atoms is preferred, an alkyl group having 1 to 5 carbon atoms is even more preferred, a methyl group or an ethyl group is even more preferred, and a methyl group is particularly preferred. When the chain saturated hydrocarbon group represented by Ra' 12 and Ra' 13 is substituted, examples of the substituent include the same groups as those for Ra x5 above.

[0054] In formula (a1-r2-4), Ra' 14 is a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group in Ra' 14 include a linear or branched alkyl group, or a cyclic hydrocarbon group.

[0055] The linear alkyl group in Ra'14 preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include methyl, ethyl, n-propyl, n-butyl, and n-pentyl. Among these, methyl, ethyl, or n-butyl is preferred, and methyl or ethyl is even more preferred.

[0056] The branched alkyl group in Ra'14 preferably has 3 to 10 carbon atoms, more preferably 3 to 5. Specifically, examples include isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl, 1,1-diethylpropyl, and 2,2-dimethylbutyl. Isopropyl is preferred.

[0057] When Ra' 14 is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. The aliphatic hydrocarbon group as the monocyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The aliphatic hydrocarbon group as the polycyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane. The polycycloalkane is preferably one having 7 to 12 carbon atoms. Specifically, adamantane, Alkane, Iso Alkane, tricyclodecane, tetracyclododecane, etc.

[0058] Examples of the aromatic hydrocarbon group in Ra'14 include the same as those in Ra'104. Among them, Ra'14 is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or phenanthrene, even more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, or anthracene, particularly preferably a group obtained by removing one or more hydrogen atoms from naphthalene or anthracene, and most preferably a group obtained by removing one or more hydrogen atoms from naphthalene. As the substituent that Ra' 14 may have, there are exemplified the same substituents as those that Ra 104 may have.

[0059] When Ra' 14 in formula (a1-r2-4) is a naphthyl group, the position at which it is bonded to the tertiary carbon atom in the aforementioned formula (a1-r2-4) may be either the 1-position or the 2-position of the naphthyl group. When Ra'14 in formula (a1-r2-4) is an anthracene group, the position at which it is bonded to the tertiary carbon atom in formula (a1-r2-4) may be any of the 1-position, 2-position, or 9-position of the anthracene group.

[0060] Specific examples of the group represented by the aforementioned formula (a1-r2-1) are given below.

[0061]

[0062]

[0063]

[0064] Specific examples of the group represented by the aforementioned formula (a1-r2-2) are given below.

[0065]

[0066]

[0067]

[0068] Specific examples of the group represented by the aforementioned formula (a1-r2-3) are given below.

[0069]

[0070] Specific examples of the group represented by the aforementioned formula (a1-r2-4) are given below.

[0071]

[0072] Tertiary alkyloxycarbonyl acid dissociative group: Among the aforementioned polar groups, examples of acid-dissociable groups for protecting hydroxyl groups include acid-dissociable groups represented by the following general formula (a1-r-3) (hereinafter sometimes referred to as "tertiary alkyloxycarbonyl acid-dissociable groups" for convenience).

[0073] [In the formula, Ra'7 to Ra'9 are each an alkyl group.]

[0074] In formula (a1-r-3), each of Ra'7 to Ra'9 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Furthermore, the total number of carbon atoms of the alkyl groups is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0075] Secondary alkyl ester type acid dissociative group: Among the above polar groups, examples of acid-dissociable groups for protecting carboxyl groups include acid-dissociable groups represented by the following general formula (a1-r-4).

[0076] [In the formula, Ra'10 is a hydrocarbon group, Ra'11a and Ra'11b are each 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 may be bonded to each other to form a ring, and Ra'11a or Ra'11b and Ra'12 may be bonded to each other to form a ring].

[0077] In the formula, the hydrocarbon groups in Ra'10 and Ra'12 include the same ones as those mentioned above for Ra'3. In the formula, examples of the alkyl group in Ra' 11a and Ra' 11b include the same ones as the alkyl group in Ra' 1 described above. In the formula, the hydrocarbon groups in Ra'10 and Ra'12 and the alkyl groups in Ra'11a and Ra'11b may also have substituents. Examples of such substituents include the aforementioned Ra x5.

[0078] Ra'10 and Ra'11a or Ra'11b may also be bonded to each other to form a ring, which may be a polycyclic ring, a monocyclic ring, an alicyclic ring, or an aromatic ring. The alicyclic and aromatic rings may also contain heteroatoms.

[0079] As Ra'10 and Ra'11a or Ra'11b bonded to each other to form a ring, among the above, preferably a monocyclic olefin, a ring in which a portion of the carbon atoms of a monocyclic olefin is substituted with a heteroatom (oxygen atom, sulfur atom, etc.), or a monocyclic diene, preferably a cycloolefin having 3 to 6 carbon atoms, preferably cyclopentene or cyclohexene.

[0080] Ra'10 and Ra'11a or Ra'11b may be bonded to form a condensed ring. Specific examples of such condensed rings include indane and the like.

[0081] The ring formed by the mutual bonding of Ra'10 and Ra'11a or Ra'11b may also have a substituent. Examples of such substituents include the aforementioned Ra x5.

[0082] Ra'11a or Ra'11b and Ra'12 may also be bonded to each other to form a ring, and examples of such a ring include the same ring as the ring formed by bonding Ra'10 and Ra'11a or Ra'11b to each other.

[0083] Specific examples of the group represented by the above formula (a1-r-4) are given below.

[0084]

[0085] Examples of the structural unit (a1) include a structural unit derived from an acrylic ester in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent, a structural unit derived from an acrylamide, a structural unit derived from hydroxystyrene or a hydroxystyrene derivative in which at least some of the hydrogen atoms in the hydroxyl group are protected by a substituent containing the aforementioned acid-decomposable group, and a structural unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative in which at least some of the hydrogen atoms in the -C(=O)-OH group are protected by a substituent containing the aforementioned acid-decomposable group.

[0086] Specific examples of the structural unit (a1) are shown below. In the following formulae, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096] The constituent unit (a1) of the component (A1) may be one type or two or more types. As the constituent unit (a1), in order to more easily improve the characteristics (sensitivity, shape, etc.) in electron beam or EUV lithography, the constituent unit represented by the aforementioned formula (a1-1) is more preferred. Among them, as the structural unit (a1), a structural unit represented by the following general formula (a1-1-1) or a structural unit represented by the following general formula (a1-1-2) is particularly preferred.

[0097] [In the formula, Ra 1″ is an acid-dissociable group represented by the general formula (a1-r2-1), (a1-r2-3), or (a1-r2-4). * indicates the bonding site.]

[0098] [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 001 is a single bond or a divalent linking group. Ya 01 is a single bond or a divalent linking group. Rax 01 is an acid-dissociable group represented by the general formula (a1-r2-1), (a1-r2-3), or (a1-r2-4). q is an integer from 0 to 3. n is an integer greater than 1. However, n ≤ q × 2 + 4.]

[0099] In the aforementioned formula (a1-1-1), R, Va1 and n a1 are the same as R, Va1 and n a1 in the aforementioned formula (a1-1).

[0100] In the aforementioned formula (a1-1-2), Ya 001 and Ya 01 are preferably single bonds.

[0101] The acid-dissociable groups represented by the general formula (a1-r2-1), (a1-r2-3), or (a1-r2-4) are described above. Of these, acid-dissociable groups represented by the general formula (a1-r2-1) or (a1-r2-4) are particularly suitable for enhancing reactivity in EB or EUV applications. The acid-dissociable group in the aforementioned formula (a1-1-1) is preferably an acid-dissociable group represented by the general formula (a1-r2-1).

[0102] The ratio of the structural units (a1) in the component (A1) relative to the total of all the structural units of the component (A1) (100 mol%) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, even more preferably 30 to 70 mol%, and particularly preferably 40 to 60 mol%. By setting the ratio of the constituent unit (a1) above the lower limit of the preferred range, lithographic characteristics such as sensitivity, CDU, resolution, and roughness improvement are improved. On the other hand, if the ratio is below the upper limit of the preferred range, a balance with other constituent units is achieved, and various lithographic characteristics are improved.

[0103] Other components The component (A1) may have other structural units in addition to the structural unit (a1) as needed. Examples of other structural units include a structural unit (a10) represented by the general formula (a10-1) described below; a structural unit (a2) comprising a lactone-containing cyclic group; and a structural unit (a8) derived from a compound represented by the general formula (a8-1) described below.

[0104] Regarding the constituent unit (a10): The structural unit (a10) is a structural unit represented by the following general formula (a10-1) (excluding those corresponding to the structural unit (a1)).

[0105] [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. Yax1 is a single bond or a divalent linking group. Wax1 is an aromatic hydrocarbon group which may have a substituent. Nax1 is an integer greater than or equal to 1.]

[0106] In the aforementioned formula (a10-1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms. In view of industrial availability, a hydrogen atom, a methyl group, or a trifluoromethyl group is more preferred. A hydrogen atom or a methyl group is even more preferred, and a hydrogen atom is particularly preferred.

[0107] In the aforementioned formula (a10-1), Yax1 is a single bond or a divalent linking group. In the above chemical formula, the divalent linking group in Yax1 is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent and a divalent linking group containing a heteroatom.

[0108] As Yax1, a single bond, an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof is preferred, and a single bond or an ester bond [-C(=O)-O-, -OC(=O)-] is even more preferred.

[0109] In the aforementioned formula (a10-1), Wa x1 is an aromatic hydrocarbon group which may have a substituent. Examples of the aromatic hydrocarbon group in Wax1 include groups formed by removing (n ax1 + 1) hydrogen atoms from an aromatic ring that may have substituents. The aromatic ring 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, even more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which a portion of the carbon atoms constituting the aromatic hydrocarbon rings are substituted with heteroatoms. Examples of heteroatoms in the aromatic heterocyclic ring include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of the aromatic heterocyclic ring include pyridine rings and thiophene rings. Furthermore, as the aromatic hydrocarbon group in Wa x1, there is also mentioned a group obtained by removing (nax1+1) hydrogen atoms from an aromatic compound containing an aromatic ring which may also have two or more substituents (for example, biphenyl, fluorene, etc.). Among the above, Wax1 is preferably a group obtained by removing (nax1+1) hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, more preferably a group obtained by removing (nax1+1) hydrogen atoms from benzene or naphthalene, and even more preferably a group obtained by removing (nax1+1) hydrogen atoms from benzene.

[0110] The aromatic hydrocarbon group in Wax1 may or may not have a substituent. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, and alkyl halides. Examples of such substituents include the same alkyl groups, alkoxy groups, halogen atoms, and alkyl halides as those listed for the cyclic aliphatic hydrocarbon group in Yax1. The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, even more preferably an ethyl group or a methyl group, and particularly preferably a methyl group. The aromatic hydrocarbon group in Wax1 is preferably unsubstituted.

[0111] In the aforementioned formula (a10-1), n ​​ax1 is an integer greater than or equal to 1, preferably an integer from 1 to 10, more preferably an integer from 1 to 5, further preferably 1, 2 or 3, and particularly preferably 1 or 2.

[0112] Specific examples of the structural unit (a10) represented by the above formula (a10-1) are shown below. In the following formulae, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0113]

[0114]

[0115]

[0116] The constituent unit (a10) contained in the component (A1) may be one type or two or more types. When the component (A1) has the structural unit (a10), the ratio of the structural unit (a10) in the component (A1) relative to the total of all the structural units constituting the component (A1) (100 mol%) is preferably 20 to 80 mol%, more preferably 30 to 70 mol%, and even more preferably 30 to 60 mol%. By setting the ratio of the component unit (a10) to be above the lower limit, it is easy to further improve the sensitivity. On the other hand, by setting it below the upper limit, it is easy to achieve a balance with other components.

[0117] Regarding constituent unit (a2): The component (A1) further has a structural unit (a2) containing a lactone-containing cyclic group (excluding those corresponding to the structural unit (a1)). The lactone-containing cyclic group in the structural unit (a2) is effective in improving the adhesion of the resist film to the substrate when the component (A1) is used in the formation of a resist film. Furthermore, the presence of the structural unit (a2) improves lithographic properties by, for example, appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development.

[0118] A "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -OC(=O)- in its ring backbone. A group containing only the lactone ring is counted as the first ring. A group containing only the lactone ring is called a monocyclic group. A group containing other ring structures, regardless of their structure, is called a polycyclic group. A lactone-containing cyclic group may be either a monocyclic group or a polycyclic group. The lactone-containing cyclic group in the structural unit (a2) is not particularly limited, and any group can be used. Specifically, groups represented by the following general formulas (a2-r-1) to (a2-r-7) are exemplified.

[0119] [In the formula, Ra' and Ra' are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, or a lactone-containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms, an oxygen atom, or a sulfur atom, which may also contain an oxygen atom (-O-) or a sulfur atom (-S-); n' is an integer from 0 to 2; and m' is 0 or 1. * indicates a bonding site (hereinafter, the same).]

[0120] In the aforementioned general formulas (a2-r-1) to (a2-r-7), the alkyl group represented by R' is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, and hexyl. Among these, methyl or ethyl are preferred, with methyl being particularly preferred. The alkoxy group in Ra'21 is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the alkyl group listed above as the alkyl group in Ra'21 is linked to an oxygen atom (-O-). The halogen atom in Ra' 21 is preferably a fluorine atom. Examples of the halogenated alkyl group in Ra'21 include groups in which some or all of the hydrogen atoms of the alkyl group in Ra'21 are substituted with the aforementioned halogen atoms. The halogenated alkyl group is preferably a fluorinated alkyl group, particularly a perfluoroalkyl group.

[0121] In -COOR" and -OC(=O)R" in Ra' 21, 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. When R" is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and is particularly preferably a methyl group or an ethyl group. When R" is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, there can be exemplified groups 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; groups obtained by removing one or more hydrogen atoms from a polycycloalkane such as a bicycloalkane, a tricycloalkane, or a tetracycloalkane. More specifically, there can be exemplified groups obtained by removing one or more hydrogen atoms from a monocycloalkane such as cyclopentane or cyclohexane; groups obtained by removing one or more hydrogen atoms from adamantane, orthocyclopent ... Alkane, Iso Polycycloalkanes such as cycloalkane, tricyclodecane, tetracyclododecane, etc., from which one or more hydrogen atoms are removed. Examples of the lactone-containing cyclic group in R" include the same groups as those represented by the aforementioned general formulas (a2-r-1) to (a2-r-7). The hydroxyalkyl group in Ra' 21 preferably has 1 to 6 carbon atoms. Specifically, there are groups in which at least one hydrogen atom of the alkyl group in Ra' 21 is substituted with a hydroxyl group.

[0122] As Ra' 21, among the above, each independently represents preferably a hydrogen atom or a cyano group.

[0123] In the aforementioned 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, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group having -O- or -S- at the terminal or between carbon atoms of the alkylene group, such as -O-CH2-, -CH2-O-CH2-, -S-CH2-, and -CH2-S-CH2-. A" is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0124] Specific examples of the groups represented by general formulae (a2-r-1) to (a2-r-7) are given below.

[0125]

[0126]

[0127] Among them, the structural unit (a2) is preferably a structural unit derived from an acrylic acid ester in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent. The relevant structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

[0128] [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 21 is a single bond or a divalent linking group. La 21 is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, with R' representing a hydrogen atom or a methyl group. However, when La 21 is -O-, Ya 21 will not become -CO-. Ra 21 is a cyclic group containing a lactone.]

[0129] In the aforementioned formula (a2-1), R is the same as described 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. In view of industrial availability, a hydrogen atom or a methyl group is particularly preferred.

[0130] In the aforementioned formula (a2-1), the divalent linking group in Ya21 is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent and a divalent linking group containing a heteroatom.

[0131] Ya21 is preferably a single bond, an ester bond [—C(═O)—O—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof.

[0132] In the aforementioned formula (a2-1), Ya 21 is a single bond, and La 21 is preferably -COO- or -OCO-.

[0133] In the aforementioned formula (a2-1), Ra 21 is a lactone-containing cyclic group. As the lactone-containing cyclic group in Ra 21, there are suitably exemplified groups represented by the aforementioned general formulae (a2-r-1) to (a2-r-7).

[0134] The constituent unit (a2) contained in the component (A1) may be one type or two or more types. When the component (A1) has the structural unit (a2), the ratio of the structural unit (a2) relative to the total of all the structural units of the component (A1) (100 mol%) is preferably 1 to 20 mol%, more preferably 1 to 15 mol%, and even more preferably 1 to 10 mol%. By setting the ratio of the constituent unit (a2) to above the preferred lower limit, the effect brought about by the inclusion of the constituent unit (a2) can be fully obtained according to the aforementioned effect. If it is below the upper limit, a balance with other constituent units can be achieved, and various micro-photographic characteristics are better.

[0135] Regarding the constituent unit (a8): The structural unit (a8) is a structural unit derived from a compound represented by the following general formula (a8-1). However, those corresponding to the constituent unit (a0) are excluded.

[0136] [In the formula, W2 is a group containing a polymerizable group. Yax2 is a single bond or a linking group with a valence of (nax2+1). Yax2 and W2 may also form a condensed ring. R1 is a fluorinated alkyl group having 1 to 12 carbon atoms. R2 is an organic group having 1 to 12 carbon atoms which may also have a fluorine atom, or a hydrogen atom. R2 and Yax2 may also be bonded to each other to form a ring structure. nax2 is an integer from 1 to 3].

[0137] The "polymerizable group" in the polymerizable group-containing group of W2 means a group in which a compound having a polymerizable group can be polymerized by free radical polymerization, for example, a group containing multiple bonds between carbon atoms such as ethylenic double bonds.

[0138] The group containing a polymerizable group may be a group consisting solely of a polymerizable group or a group consisting of a polymerizable group and a group other than the polymerizable group. Examples of the group other than the polymerizable group include a divalent hydrocarbon group that may have a substituent and a divalent linking group containing a heteroatom. As the group containing a polymerizable group, a group represented by the chemical formula: C(R X11)(R X12)=C(R X13)-Ya x0- is suitably exemplified. In this chemical formula, R X11, R X12, and R X13 are each 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 is a single bond or a divalent linking group.

[0139] Examples of the condensed ring formed by Yax2 and W2 include a condensed ring formed by a polymerizable group at W2 and Yax2, and a condensed ring formed by a group other than a polymerizable group at W2 and Yax2. The condensed ring formed by Yax2 and W2 may also have a substituent.

[0140] Specific examples of the constituent unit (a8) are shown below. In the following formula, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0141]

[0142] In the above examples, it is preferred that the constituent unit (a8) is at least one selected from the group consisting of constituent units represented by chemical formulas (a8-1-01) to (a8-1-04), (a8-1-06), (a8-1-08), (a8-1-09) and (a8-1-10), and it is even more preferred that the constituent unit (a8) is at least one selected from the group consisting of constituent units represented by chemical formulas (a8-1-01) to (a8-1-04) and (a8-1-09).

[0143] The constituent unit (a8) contained in the component (A1) may be one type or two or more types. The ratio of the structural unit (a8) in the component (A1) is preferably 50 mol% or less, and more preferably 0 to 30 mol% relative to the total of all the structural units constituting the component (A1) (100 mol%).

[0144] The component (A1) contained in the resist composition may be used alone or in combination of two or more. In the resist composition of this embodiment, the component (A1) includes a polymer compound having a repeating structure of the structural unit (a1). As the component (A1), among those mentioned above, a polymer compound having a repeating structure of the structural unit (a1) and the structural unit (a10) can be suitably mentioned.

[0145] In the polymer compound having a repeating structure of the constituent units (a1) and the constituent units (a10), the ratio of the constituent units (a1) relative to the total of all the constituent units constituting the polymer compound (100 mol %) is preferably 10 to 90 mol %, more preferably 20 to 80 mol %, even more preferably 30 to 70 mol %, and particularly preferably 40 to 60 mol %. Furthermore, the ratio of the constituent units (a10) in the polymer compound is preferably 10 to 90 mol %, more preferably 20 to 80 mol %, even more preferably 30 to 70 mol %, and particularly preferably 40 to 60 mol %, relative to the total of all constituent units constituting the polymer compound (100 mol %).

[0146] The relevant (A1) component can be produced by dissolving the monomers from which the constituent units are derived in a polymerization solvent, adding a free radical polymerization initiator such as azobisisobutyronitrile (AIBN) or azobisisobutyric acid dimethyl (such as V-601), and polymerizing. Alternatively, the relevant component (A1) is produced by dissolving a monomer derived from the structural unit (a1) and a monomer derived from a structural unit other than the necessary structural unit (a1) (e.g., the derived structural unit (a10)) in a polymerization solvent, adding the above-mentioned free radical polymerization initiator to carry out polymerization, and then performing a deprotection reaction. Furthermore, during polymerization, for example, by using HS-CH2-CH2-CH2-C(CF3)2-OH can be used as a chain transfer agent, and a -C(CF3)2-OH group can also be introduced at the terminal. In this way, copolymers containing hydroxyalkyl groups in which some of the hydrogen atoms of the introduced alkyl group are replaced with fluorine atoms are more effective in reducing image defects and LER (line edge roughness: uneven surface roughness of line sidewalls).

[0147] The weight average molecular weight (Mw) of the component (A1) (based on polystyrene conversion as determined by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and even more preferably 3,000 to 20,000. If the Mw of component (A1) is below the preferred upper limit of this range, it has sufficient solubility in the resist solvent when used as a resist. If it is above the preferred lower limit of this range, the dry etching resistance or the cross-sectional shape of the resist pattern is better. 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.

[0148] ･About ingredient (A2) In the resist composition of this embodiment, as component (A), a base material component (hereinafter referred to as "component (A2)") which is not equivalent to the aforementioned component (A1) and whose solubility in the developer changes due to the action of acid may be used in combination. The component (A2) is not particularly limited, and any component may be selected from a plurality of components conventionally known as base materials for chemically amplified resist compositions. As the component (A2), a high molecular compound or a low molecular compound may be used alone or in combination of two or more.

[0149] The proportion of component (A1) in component (A) relative to the total mass of component (A) is preferably 25% by mass or greater, more preferably 50% by mass or greater, even more preferably 75% by mass or greater, and may be 100% by mass. When this proportion is 25% by mass or greater, it is easy to form a resist pattern having various excellent lithographic properties, such as high sensitivity, resolution, and improved roughness.

[0150] In the resist composition of this embodiment, the content of component (A) is adjusted according to the thickness of the resist film to be formed.

[0151] <Acid Generator Component (B)> The component (B) in the resist composition of this embodiment includes a compound (B0) represented by the following general formula (b0) (hereinafter also referred to as "component (B0)").

[0152] Compound (B0) The component (B0) is a compound represented by the following general formula (b0).

[0153] [wherein, Ar is an arylene group or a heteroarylene group, R and R are each independently a substituent other than an iodine atom, L is a divalent linking group or a single bond, L is a divalent linking group, V is a single bond, an alkylene group, or a fluorinated alkylene group, R is a hydrogen atom, a fluorinated alkylene group having 1 to 5 carbon atoms, or a fluorine atom, n is an integer from 2 to 4, n is an integer from 1 to 3, n is an integer from 0 to 2, n is an integer of 0 or greater, n is an integer of 1 or greater, M represents an m-valent organic cation, and m is an integer of 1 or greater]

[0154] {Anion portion of component (B0)} In the above general formula (b0), Ar0 is an arylene group or a heteroarylene group. Examples of the aryl group in Ar0 include groups obtained by removing two hydrogen atoms from an aromatic ring. Examples of the aromatic ring include benzene, naphthalene, anthracene, and phenanthrene. Specifically, the aryl group in Ar0 is preferably a phenylene group.

[0155] Examples of the heteroaryl group in Ar0 include groups obtained by removing two hydrogen atoms from an aromatic heterocycle. Examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

[0156] In the above general formula (b0), Ar 0 is preferably an arylene group, and more preferably a phenylene group.

[0157] In the general formula (b0), Rm1 and Rm2 are each independently a substituent other than an iodine atom, and examples of such a substituent include a hydroxyl group, an alkyl group, a fluorinated alkyl group, a fluorine atom, and a chlorine atom. The alkyl group in the alkyl group and the fluorinated alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group or an ethyl group.

[0158] In the above general formula (b0), R m1 and R m2 are each independently an alkyl group, a fluorinated alkyl group, or preferably a fluorine atom.

[0159] In the above general formula (b0), L 01 is a divalent linking group or a single bond, and L 02 is a divalent linking group. As the divalent linking group in L 01 and L 02, a divalent linking group containing an oxygen atom is preferably mentioned. When L01 and L02 are divalent linking groups containing oxygen atoms, L01 and L02 may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms. Examples of divalent linking groups containing oxygen atoms include non-hydrocarbon oxygen-containing linking groups such as oxygen atoms (ether bonds: -O-), ester bonds (-C(=O)-O-), oxycarbonyl groups (-OC(=O)-), amide bonds (-C(=O)-NH-), carbonyl groups (-C(=O)-), and carbonate bonds (-OC(=O)-O-); and combinations of these non-hydrocarbon oxygen-containing linking groups with alkylene groups. These combinations may also be further linked to sulfonyl groups (-SO2-).

[0160] More specifically, the divalent linking group in L01 and L02 includes -O-, -CO-, -OCO-, -COO-, -SO2-, -N(Ra)-C(=O)-, -N(Ra)-, -C(Ra)(Ra)-N(Ra)-, -C(Ra)(N(Ra)(Ra))-, or -C(=O)-N(Ra)-. Each Ra is independently a hydrogen atom or an alkyl group.

[0161] In the general formula (b0), L 01 is preferably a divalent linking group, more preferably a divalent linking group containing an oxygen atom, further preferably -OCO-, -COO- or -C(=O)-N(Ra)-, and particularly preferably -OCO- or -COO-.

[0162] In the general formula (b0), L 02 is preferably a divalent linking group, more preferably a divalent linking group containing an oxygen atom, more preferably -OCO-, -COO- or -C(=O)-N(Ra)-, and particularly preferably -OCO-, -COO- or -C(=O)-NH-.

[0163] In the above general formula (b0), Vb0 is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and the fluorinated alkylene group in Vb0 preferably each have 1 to 4 carbon atoms, more preferably 1 to 3 carbon atoms. Examples of the fluorinated alkylene group in Vb0 include groups in which some or all of the hydrogen atoms of the alkylene group are substituted with fluorine atoms.

[0164] In the general formula (b0), Vb0 is preferably an alkylene group or a fluorinated alkylene group, more preferably an alkylene group having 1 to 4 carbon atoms or a fluorinated alkylene group having 1 to 4 carbon atoms, more preferably a methylene group, -CH(CF3)-, -CH2CH2CF2-, or -CH2CH2CHF-, and particularly preferably -CH(CF3)-, -CH2CH2CF2-, or -CH2CH2CHF-.

[0165] In the above general formula (b0), R 0 is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom. R0 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, more preferably a fluorine atom.

[0166] In the above general formula (b0), nb1 and nb5 represent the number of iodine atoms (I). nb1 is an integer between 2 and 4. nb5 is an integer greater than 1, preferably an integer between 2 and 5. The total number of nb1 and nb5 is preferably an integer from 4 to 9, more preferably 5 or 6, and even more preferably 5.

[0167] In the above general formula (b0), nb2 is an integer of 1 to 3, preferably 1 or 2. In the above general formula (b0), when nb2 is 2 or 3, the multiple numbers of nb4, nb5, Ar0 and L02 may be the same or different.

[0168] In the above general formula (b0), nb3 is an integer from 0 to 2, preferably 0 or 1, and more preferably 0. In the above general formula (b0), when nb3 is 2, the plurality of R m2 may be the same or different.

[0169] In the above general formula (b0), nb4 is an integer greater than 0, preferably 0 or 1, and more preferably 0. In the above general formula (b0), when nb4 is 2 or greater, the plurality of R m1 may be the same or different.

[0170] Preferred specific examples of the anion portion of the component (B0) are shown below.

[0171]

[0172]

[0173]

[0174]

[0175]

[0176]

[0177]

[0178]

[0179]

[0180] As the anion portion of the component (B0), among the above, an anion represented by any one of the chemical formulas (b0-an-001), (b0-an-009), (b0-an-010), (b0-an-011), (b0-an-013), (b0-an-015), (b0-an-020), (b0-an-023), (b0-an-025) to (b0-an-027), (b0-an-030) to (b0-an-032), (b0-an-045), (b0-an-094) to (b0-an-097) is preferred. Anions represented by any one of the chemical formulas (b0-an-011), (b0-an-023), (b0-an-030), (b0-an-095) to (b0-an-097) are more preferred, and anions represented by any one of the chemical formulas (b0-an-011), (b0-an-023), (b0-an-030), (b0-an-095) to (b0-an-097) are even more preferred.

[0181] {Cation portion of component (B0)} In the above general formula (b0), M m+ represents an m-valent organic cation, preferably a tertium cation or an iodonium cation. m is an integer greater than or equal to 1.

[0182] Preferred examples of the cationic moiety ((M m+) 1 / m) include organic cations represented by the following general formulas (ca-1) to (ca-3).

[0183] [In the formula, R 201 to R 207 each independently represents an aryl group, an alkyl group, or an alkenyl group which may be substituted. R 201 to R 203 and R 206 to R 207 may be bonded to each other and together with the sulfur atom in the formula to form a ring. R 208 to R 209 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R 210 represents an aryl group which may be substituted, an alkyl group which may be substituted, an alkenyl group which may be substituted, or a cyclic group containing -SO 2- which may be substituted. L 201 represents -C(=O)- or -C(=O)-O-.]

[0184] In the above general formulas (ca-1) to (ca-3), the aryl group in R 201 to R 207 includes unsubstituted aryl groups having 6 to 20 carbon atoms, preferably phenyl or naphthyl. The alkyl group in R 201 to R 207 is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. The alkenyl group in R 201 to R 207 preferably has 2 to 10 carbon atoms. Examples of substituents that may be possessed by R 201 to R 207 and R 210 include alkyl groups, halogen atoms, halogenated alkyl groups, carbonyl groups, cyano groups, amino groups, aryl groups, and groups represented by the following general formulas (ca-r-1) to (ca-r-7).

[0185] [In the formula, R'201 is independently a hydrogen atom, a cyclic group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent.]

[0186] The cyclic group which may have a substituent: 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 refers to a hydrocarbon group that is not aromatic. Furthermore, an aliphatic hydrocarbon group may be saturated or unsaturated, but saturated is generally preferred.

[0187] The aromatic hydrocarbon group in R'201 is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, even more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. However, this number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring contained in the aromatic hydrocarbon group in R'201 include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which a portion of the carbon atoms constituting the aromatic rings are substituted with heteroatoms. Examples of heteroatoms in the aromatic heterocycle include oxygen, sulfur, and nitrogen atoms. Specific examples of the aromatic hydrocarbon group in R'201 include groups in which one hydrogen atom is removed from the aforementioned aromatic ring (aryl groups: for example, phenyl and naphthyl), and groups in which one hydrogen atom of the aforementioned aromatic ring is substituted with an alkylene group (for example, arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, and 2-naphthylethyl). The aforementioned alkylene group (the alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0188] Examples of the cyclic aliphatic hydrocarbon group in R'201 include aliphatic hydrocarbon groups containing a ring in their structure. Examples of the aliphatic hydrocarbon group containing a ring in this 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 straight-chain or branched aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is inserted in the middle of a straight-chain or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms. The aforementioned alicyclic hydrocarbon group may also be a polycyclic group or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocyclic alkane is preferred. As the monocyclic alkane, a group having 3 to 6 carbon atoms is preferred, specifically, cyclopentane, cyclohexane, etc. As a polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane is preferably a group having 7 to 30 carbon atoms. Among them, as the polycycloalkane, adamantane, Alkane, Iso More preferred are polycycloalkanes having a cross-linked ring system such as tricyclodecane, tetracyclododecane, and the like; and polycycloalkanes having a condensed ring system such as a cyclic group having a steroid skeleton.

[0189] Among them, the cyclic aliphatic hydrocarbon group in R'201 is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane, and more preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and is preferably an adamantyl group, a cyclopent ... The group is particularly preferred, and the most preferred is adamantyl group.

[0190] The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred, and specific examples include methylene [-CH2-], ethylene [-(CH2)2-], trimethylene [-(CH2)3-], tetramethylene [-(CH2)4-], and pentamethylene [-(CH2)5-]. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specific examples include -CH(CH 3)-, -CH(CH 2CH 3)-, -C(CH 3) 2-, -C(CH 3)(CH 2CH 3)-, -C(CH 3)(CH 2CH 2CH 3)-, -C(CH 2CH 3) 2- and the like alkylene groups; -CH(CH 3)CH 2-, -CH(CH 3)CH 2-, -C ... -CH(CH 3)CH(CH 3)-, -C(CH 3) 2CH 2-, -CH(CH 2CH 3)CH 2-, -C(CH 2CH 3) 2-CH 2- and other alkyl ethylidene groups; -CH(CH 3)CH 2CH 2-, -CH 2CH(CH 3)CH 2- and other alkyl trimethyl groups; Alkyl groups such as -CH(CH 3)CH 2CH 2CH 2-, -CH 2CH(CH 3)CH 2CH 2-, and alkyl tetramethylene groups are also included. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0191] Furthermore, the cyclic hydrocarbon group in R'201 may also contain heteroatoms such as heterocycles. Specifically, examples include lactone-containing cyclic groups represented by the aforementioned general formulas (a2-r-1) to (a2-r-7), -SO2--containing cyclic groups represented by the aforementioned general formulas (b5-r-1) to (b5-r-4), and heterocyclic groups represented by other aforementioned chemical formulas (r-hr-1) to (r-hr-16).

[0192] Examples of the substituent in the cyclic group of R'201 include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and is most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, or tert-butoxy, and most preferably methoxy or ethoxy. The halogen atom as a substituent is preferably a fluorine atom. The halogenated alkyl group as a substituent is an alkyl group having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., in which some or all of the hydrogen atoms are substituted by the aforementioned halogen atoms. The carbonyl group as a substituent is a group that replaces the methylene group (-CH2-) constituting the cyclic hydrocarbon group.

[0193] A chain alkyl group which may also have a substituent: The chain alkyl group represented by R'201 may be either linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched chain alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl.

[0194] A chain alkenyl group which may also have a substituent: The chain alkenyl group represented by R'201 may be either 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 ethenyl, propenyl (allyl), and butenyl. Examples of branched alkenyl groups include 1-methylvinyl, 2-methylvinyl, 1-methylpropenyl, and 2-methylpropenyl. As the chain alkenyl group, among the above, a straight-chain alkenyl group is preferred, a vinyl group and a propenyl group are more preferred, and a vinyl group is particularly preferred.

[0195] Examples of substituents in the chain alkyl or alkenyl group of R'201 include alkoxy groups, halogen atoms, halogenated alkyl groups, hydroxyl groups, carbonyl groups, nitro groups, amino groups, and the cyclic groups mentioned above for R'201.

[0196] In addition to the above, examples of the cyclic group which may have a substituent, the chain alkyl group which may have a substituent, or the chain alkenyl group which may have a substituent include the same acid-dissociable groups as those represented by the above formula (a1-r-2).

[0197] Among them, R'201 is preferably a cyclic group that may be substituted, and more preferably a cyclic hydrocarbon group that may be substituted. More specifically, it is preferably a group obtained by removing one or more hydrogen atoms from a phenyl group, a naphthyl group, or a polycycloalkane group; a lactone-containing cyclic group represented by the aforementioned general formulas (a2-r-1) to (a2-r-7); or a -SO2- containing cyclic group represented by the aforementioned general formulas (b5-r-1) to (b5-r-4).

[0198] In the general formulas (ca-1) to (ca-3), when R 201 to R 203 and R 206 to R 207 are bonded to each other and to form a ring with the sulfur atom in the formula, they may be bonded via a heteroatom such as a sulfur atom, an oxygen atom, a nitrogen atom, or a functional group such as a carbonyl group, -SO-, -SO 2-, -SO 3-, -COO-, -CONH-, or -N(RN)- (where RN is an alkyl group having 1 to 5 carbon atoms). The ring formed is preferably a 3- to 10-membered ring, and particularly preferably a 5- to 7-membered ring, containing the sulfur atom in the formula. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenothioxane ring, a tetrahydrothiophenone ring, and a tetrahydrothiopyran ring.

[0199] R 208 to R 209 each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. When they are alkyl groups, they may be bonded to each other to form a ring.

[0200] R 210 represents an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a cyclic group containing -SO 2 - which may have a substituent. Examples of the aryl group in R 210 include unsubstituted aryl groups having 6 to 20 carbon atoms, preferably phenyl or naphthyl. The alkyl group in R 210 is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. The alkenyl group in R 210 preferably has 2 to 10 carbon atoms. The cyclic group containing -SO 2- which may have a substituent in R 210 is preferably a "polycyclic group containing -SO 2-", and more preferably a group represented by the above general formula (b5-r-1).

[0201] Specifically, suitable cations represented by the aforementioned formula (ca-1) include cations represented by the following chemical formulas (ca-1-1) to (ca-1-70).

[0202] []

[0203] []

[0204] [In the formula, g1, g2, and g3 represent the number of repetitions, g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20.]

[0205]

[0206]

[0207] [][In the formula, R"201 is a hydrogen atom or a substituent. The substituent is the same as those exemplified as the substituents that R201 to R207 and R210 to R212 may have.]

[0208] Specific examples of suitable cations represented by the above formula (ca-2) include diphenyliodonium cations and bis(4-tert-butylphenyl)iodonium cations.

[0209] Specifically, suitable cations represented by the aforementioned formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

[0210]

[0211] Preferred specific examples of the component (B0) are shown below.

[0212]

[0213]

[0214]

[0215] Among the above, the component (B0) is preferably a compound represented by any one of the chemical formulas (B0-02) to (B0-22), more preferably a compound represented by any one of the chemical formulas (B0-04), (B0-05), (B0-08), (B0-09), (B0-14), (B0-15), (B0-17) to (B0-22), and even more preferably a compound represented by any one of the chemical formulas (B0-04), (B0-08), (B0-14), (B0-17) to (B0-22).

[0216] In the resist composition of this embodiment, the component (B0) may be used alone or in combination of two or more.

[0217] In the resist composition of this embodiment, the component (B0) may be used alone or in combination of two or more. In the resist composition of this embodiment, the content of component (B0) is preferably 15 to 50 parts by mass, more preferably 20 to 50 parts by mass, and even more preferably 20 to 45 parts by mass, relative to 100 parts by mass of component (A). If the content of component (B0) is above the lower limit of the preferred range, lithographic properties such as sensitivity and line width roughness (LWR) reduction during resist pattern formation are further improved. On the other hand, if the content is below the upper limit of the preferred range, a uniform solution is easily obtained when the components of the resist composition are dissolved in an organic solvent, and the storage stability of the resist composition is further improved.

[0218] In the resist composition of this embodiment, the ratio of the component (B0) in the entire component (B) is, for example, 50% by mass or more, preferably 70% by mass or more, more preferably 95% by mass or more, and may also be 100% by mass.

[0219] The (B) component in the resist composition of this embodiment may also contain an acid generator component (B1) (hereinafter also referred to as "(B1) component") other than the above-mentioned (B0) component.

[0220] (B1) Ingredients Component (B1) includes onium salt acid generators such as iodonium salts or coronium salts; oxime sulfonate acid generators; diazomethane acid generators such as dialkyl or diaryl sulfonyldiazomethanes and poly(bissulfonyl)diazomethanes; nitrobenzyl sulfonate acid generators, iminosulfonate acid generators, and disulfonate acid generators.

[0221] Examples of onium salt acid generators include compounds represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), compounds represented by the following general formula (b-2) (hereinafter also referred to as "component (b-2)"), and compounds represented by the following general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0222] Examples of onium salt acid generators include compounds represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), compounds represented by the following general formula (b-2) (hereinafter also referred to as "component (b-2)"), and compounds represented by the following general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0223] [In the formula, R 101 and R 104 to R 108 are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. R 104 and R 105 may be bonded to each other to form a ring structure. R 102 is a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. Y 101 is a divalent linking group containing an oxygen atom or a single bond. V 101 to V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group. L 101 to L 102 are each independently a single bond or an oxygen atom. L 103 to L 105 are each independently a single bond, -CO-, or -SO 2-. m is an integer greater than 1, and M'm+ is an m-valent onium salt cation.]

[0224] {Anion Section} ･Anions in (b-1) component In formula (b-1), R 101 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

[0225] The cyclic group which may have a substituent: 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 refers to a hydrocarbon group that is not aromatic. Furthermore, an aliphatic hydrocarbon group may be saturated or unsaturated, but saturated is generally preferred.

[0226] The aromatic hydrocarbon group in R 101 is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, 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 the substituent. Specific examples of the aromatic ring contained in the aromatic hydrocarbon group in R 101 include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which a portion of the carbon atoms constituting the aromatic rings are substituted with heteroatoms. Examples of heteroatoms in the aromatic heterocycle include oxygen, sulfur, and nitrogen atoms. Specific examples of the aromatic hydrocarbon group in R 101 include groups in which one hydrogen atom is removed from the aforementioned aromatic ring (aryl groups: for example, phenyl and naphthyl), and groups in which one hydrogen atom of the aforementioned aromatic ring is substituted with an alkylene group (for example, arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, and 2-naphthylethyl). The number of carbon atoms in the aforementioned alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0227] Examples of the cyclic aliphatic hydrocarbon group in R 101 include aliphatic hydrocarbon groups containing a ring in their structure. Examples of the aliphatic hydrocarbon group containing a ring in this 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 straight-chain or branched aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is inserted in the middle of a straight-chain or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms. The aforementioned alicyclic hydrocarbon group may also be a polycyclic group or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocyclic alkane is preferred. As the monocyclic alkane, a group having 3 to 6 carbon atoms is preferred, specifically, cyclopentane, cyclohexane, etc. As a polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane is preferably a group having 7 to 30 carbon atoms. Among them, as the polycycloalkane, adamantane, Alkane, Iso More preferred are polycycloalkanes having a cross-linked ring system such as tricyclodecane, tetracyclododecane, and the like; and polycycloalkanes having a condensed ring system such as a cyclic group having a steroid skeleton.

[0228] Among them, the cyclic aliphatic hydrocarbon group in R101 is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane, and more preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and is preferably an adamantyl group, a cyclopent ... The group is more preferred, and the most preferred is adamantyl group.

[0229] 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 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, and specific examples thereof include methylene [-CH2-], ethylene [-(CH2)2-], trimethylene [-(CH2)3-], tetramethylene [-(CH2)4-], and pentamethylene [-(CH2)5-]. The branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group, and specifically, there are alkylene groups such as -CH(CH 3)-, -CH(CH 2CH 3)-, -C(CH 3) 2-, -C(CH 3)(CH 2CH 3)-, -C(CH 3)(CH 2CH 2CH 3)-, and -C(CH 2CH 3) 2-; -CH(CH 3)CH 2-, ... -CH(CH 3)CH(CH 3)-, -C(CH 3) 2CH 2-, -CH(CH 2CH 3)CH 2-, -C(CH 2CH 3) 2-CH 2- and other alkyl ethylidene groups; -CH(CH 3)CH 2CH 2-, Alkyl trimethyl groups such as -CH2CH(CH3)CH2-; alkyl tetramethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2CH2-; and alkyl alkylene groups. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0230] Furthermore, the cyclic hydrocarbon group in R 101 may also contain heteroatoms, such as heterocycles. Specifically, examples include lactone-containing cyclic groups represented by the aforementioned general formulas (a2-r-1) to (a2-r-7), -SO 2--containing cyclic groups represented by the following general formulas (b5-r-1) to (b5-r-4), and heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16). In the formulas, * indicates the bonding site of Y 101 in formula (b-1).

[0231] [In the formula, Rb' and Rb' are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, or a -SO2- containing cyclic group; B" is an alkylene group having 1 to 5 carbon atoms, an oxygen atom, or a sulfur atom, which may also contain an oxygen atom or a sulfur atom; and n' is an integer from 0 to 2. * indicates a bonding site.]

[0232] In the aforementioned general formulas (b5-r-1) to (b5-r-2), B" may also contain an alkylene group having 1 to 5 carbon atoms, 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.

[0233] In the aforementioned general formulas (b5-r-1) to (b5-r-4), Rb' and Rb' are each independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group. Among the above, preferably, each independently a hydrogen atom or a cyano group is selected.

[0234] Specific examples of the groups represented by the general formulas (b5-r-1) to (b5-r-4) are given below: "Ac" in the formula represents an acetyl group.

[0235]

[0236]

[0237]

[0238]

[0239] Examples of the substituent in the cyclic group of R 101 include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and is most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, or tert-butoxy, and most preferably methoxy or ethoxy. Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred. The halogenated alkyl group as a substituent is an alkyl group having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., in which some or all of the hydrogen atoms are substituted by the aforementioned halogen atoms. The carbonyl group as a substituent is a group that replaces the methylene group (-CH2-) constituting the cyclic hydrocarbon group.

[0240] The cyclic hydrocarbon group in R101 may also be a condensed ring group comprising a condensed ring formed by condensing an aliphatic hydrocarbon ring and an aromatic ring. Examples of the condensed ring include polycycloalkanes having a cross-linked ring system and a polycyclic skeleton condensed with one or more aromatic rings. Specific examples of the cross-linked ring system polycycloalkanes include bicyclo[2.2.1]heptane (hexane) and bicyclo[2.2.1]heptane (hexane). alkane), bicyclo[2.2.2]octane, and other bicycloalkanes. The aforementioned condensed ring formula preferably comprises a condensed ring formed by condensing a bicycloalkane with two or three aromatic rings, and more preferably comprises a condensed ring formed by condensing bicyclo[2.2.2]octane with two or three aromatic rings. Specific examples of the condensed ring formula in R 101 include those represented by the following formulas (r-br-1) to (r-br-2). In the formulas, * indicates the bonding site of Y 101 in formula (b-1).

[0241]

[0242] Examples of the substituent that the condensed cyclic group in R 101 may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an aromatic hydrocarbon group, and an alicyclic hydrocarbon group. Examples of the alkyl group, alkoxy group, halogen atom, and alkyl halide substituent of the condensed cyclic group include the same substituents as those exemplified above for the cyclic group in R 101 . Examples of the aromatic hydrocarbon group as a substituent of the aforementioned condensed cyclic group include a group in which one hydrogen atom is removed from an aromatic ring (aryl group: for example, phenyl, naphthyl, etc.), a group in which one hydrogen atom of the aforementioned aromatic ring is substituted with an alkylene group (for example, arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.), and a heterocyclic group represented by the above formulae (R-HR-1) to (R-HR-6). Examples of the alicyclic hydrocarbon group as a substituent of the condensed cyclic group include a group obtained by removing one hydrogen atom from a monocyclic alkane such as cyclopentane or cyclohexane; a group obtained by removing one hydrogen atom from a monocyclic alkane such as adamantane or cyclohexane; Alkane, Iso a group obtained by removing one hydrogen atom from a polycycloalkane such as cycloalkane, tricyclodecane, or tetracyclododecane; a lactone-containing cyclic group represented by the aforementioned general formula (a2-r-1) to (a2-r-7); a -SO2- containing cyclic group represented by the aforementioned general formula (b5-r-1) to (b5-r-4); a heterocyclic group represented by the aforementioned formula (r-hr-7) to (r-hr-16); and the like.

[0243] A chain alkyl group which may also have a substituent: The chain alkyl group represented by R 101 may be linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched chain alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl.

[0244] A chain alkenyl group which may also have a substituent: The chain alkenyl group represented by R 101 may be either linear or branched, preferably having 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 ethenyl, propenyl (allyl), and butenyl. Examples of branched alkenyl groups include 1-methylethenyl, 2-methylethenyl, 1-methylpropenyl, and 2-methylpropenyl. As the chain alkenyl group, among the above, a straight-chain alkenyl group is preferred, a vinyl group and a propenyl group are more preferred, and a vinyl group is particularly preferred.

[0245] Examples of the substituent in the chain alkyl or alkenyl group of R 101 include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the cyclic groups mentioned above for R 101.

[0246] Among the above, R 101 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, the cyclic hydrocarbon group is a group obtained by removing one or more hydrogen atoms from a phenyl group, a naphthyl group, or a polycycloalkane; a lactone-containing cyclic group represented by the aforementioned general formula (a2-r-1) to (a2-r-7); preferably, a -SO2- containing cyclic group represented by the aforementioned general formula (b5-r-1) to (b5-r-4); more preferably, a group obtained by removing one or more hydrogen atoms from a polycycloalkane; and even more preferably, an adamantyl group.

[0247] In formula (b-1), Y 101 is a single bond or a divalent linking group containing an oxygen atom. When Y 101 is a divalent linking group containing an oxygen atom, Y 101 may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms. Examples of divalent oxygen-containing linking groups include non-hydrocarbon oxygen-containing linking groups such as oxygen (ether bond: -O-), ester bond (-C(=O)-O-), oxycarbonyl (-OC(=O)-), amide bond (-C(=O)-NH-), carbonyl (-C(=O)-), and carbonate bond (-OC(=O)-O-); and combinations of such non-hydrocarbon oxygen-containing linking groups with alkylene groups. These combinations may further include sulfonyl groups (-SO2-). Examples of relevant divalent oxygen-containing linking groups include those represented by the following general formulas (y-a1-1) to (y-a1-7). Furthermore, in the following general formulas (y-al-1) to (y-al-7), R 101 in the above formula (b-1) is bonded to V' 101 in the following general formulas (y-al-1) to (y-al-7).

[0248] [In the formula, V'101 is a single bond or an alkylene group having 1 to 5 carbon atoms, and V'102 is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]

[0249] The divalent saturated hydrocarbon group in V'102 is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0250] The alkylene group in V'101 and V'102 may be a linear alkylene group or a branched alkylene group, but a linear alkylene group is preferred. Specific examples of the alkylene groups in V'101 and V'102 include methylene [-CH2-]; alkylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; ethylene groups [-CH2CH2-]; alkylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, and -CH(CH2CH3)CH2-; trimethylene (n-propylene) groups [-CH2CH2CH2-]; -CH(CH3)CH2CH2-, -CH2CH(CH3)CH 2-, etc.; alkyl trimethyl group; tetramethyl group [-CH 2CH 2CH 2CH 2-]; alkyl tetramethyl group such as -CH(CH 3)CH 2CH 2CH 2-, -CH 2CH(CH 3)CH 2CH 2-; pentamethyl group [-CH 2CH 2CH 2CH 2CH 2-], etc. Furthermore, in V'101 or V'102, a portion of the methylene groups in the aforementioned 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 hydrogen atom from a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group or polycyclic aliphatic hydrocarbon group) of Ra'3 in the aforementioned formula (a1-r-1), and is more preferably a cyclohexylene group, a 1,5-adamantene group, or a 2,6-adamantene group.

[0251] Y 101 is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, and more preferably a linking group represented by the above formulas (y-a1-1) to (y-a1-5).

[0252] In formula (b-1), V101 is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group or fluorinated alkylene group in V101 preferably has 1 to 4 carbon atoms. Examples of the fluorinated alkylene group in V101 include groups in which some or all of the hydrogen atoms in the alkylene group are substituted with fluorine atoms. V101 is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms, and more preferably a single bond or a chain fluorinated alkylene group having 1 to 4 carbon atoms.

[0253] In formula (b-1), R 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R 102 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0254] Specific examples of the anion moiety represented by the aforementioned formula (b-1) include, for example, a fluorinated alkylsulfonate anion such as a trifluoromethanesulfonate anion or a perfluorobutanesulfonate anion when Y 101 is a single bond; and an anion represented by any one of the following formulas (an-1) to (an-3) when Y 101 is a divalent linking group containing an oxygen atom.

[0255] [In the formula, R"101 is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by the above chemical formulas (R-HR-1) to (R-HR-6), a condensed cyclic group represented by the above formula (R-Br-1) or (R-Br-2), a chain alkyl group which may have a substituent, or an aromatic cyclic group which may have a substituent. R"102 is an aliphatic cyclic group which may have a substituent, a condensed cyclic group represented by the above formula (R-Br-1) or (R-Br-2), a lactone-containing cyclic group represented by the above general formulas (A2-R-1), (A2-R-3) to (A2-R-7), or a -SO2- containing cyclic group represented by the above general formulas (B5-R-1) to (B5-R-4). R"103 is an aromatic cyclic group which may be substituted, an aliphatic cyclic group which may be substituted, or a chain alkenyl group which may be substituted. V"101 is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R102 is a fluorine atom or a fluorinated alkylene group having 1 to 5 carbon atoms. Each v" is independently an integer from 0 to 3, each q" is independently an integer from 0 to 20, and n" is 0 or 1.

[0256] The aliphatic cyclic group which may have a substituent for R'101, R'102, and R'103 is preferably the group exemplified as the cyclic aliphatic hydrocarbon group for R'101 in the aforementioned formula (b-1). Examples of the substituent include the same substituents as those which may be substituted for the cyclic aliphatic hydrocarbon group for R'101 in the aforementioned formula (b-1).

[0257] The aromatic cyclic group which may have a substituent in R'101 and R'103 is preferably the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in R'101 in the aforementioned formula (b-1). Examples of the substituent include the same substituents as those which may be substituted for the aromatic hydrocarbon group in R'101 in the aforementioned formula (b-1).

[0258] The chain alkyl group which may have a substituent in R"101 is preferably the group exemplified as the chain alkyl group in R101 in the aforementioned formula (b-1). The chain alkenyl group which may have a substituent in R"103 is preferably the group exemplified as the chain alkenyl group in R101 in the aforementioned formula (b-1).

[0259] ･Anions in component (b-2) In formula (b-2), R104 and R105 are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the examples for each are the same as for R101 in formula (b-1). However, R104 and R105 may be bonded to each other to form a ring. R 104 and R 105 are preferably chain alkyl groups which may have a substituent, and are more preferably linear or branched alkyl groups, or linear or branched fluorinated alkyl groups. The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. Within the aforementioned range, the chain alkyl group of R104 and R105 preferably has a smaller carbon number, for reasons such as improved solubility in resist solvents. Furthermore, the more hydrogen atoms in the chain alkyl group of R104 and R105 are substituted with fluorine atoms, the stronger the acid strength becomes and the higher the transparency to high-energy light or electron beams below 250 nm. The ratio of fluorine atoms in the chain alkyl group, i.e., the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%. A perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms is most preferred. In formula (b-2), V 102 and V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and are the same as those for V 101 in formula (b-1). In formula (b-2), L 101 and L 102 are each independently a single bond or an oxygen atom.

[0260] ･Anions in (b-3) component In formula (b-3), R 106 to R 108 are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and are the same as for R 101 in formula (b-1). In formula (b-3), L 103 to L 105 are each independently a single bond, -CO- or -SO 2-.

[0261] {Cation Department} In the aforementioned formulas (b-1), (b-2), and (b-3), M'm+ represents an m-valent onium cation, preferably a columbite cation or an iodonium cation. m is an integer greater than or equal to 1.

[0262] As preferred cationic moieties ((M'm+) 1 / m), there are organic cations represented by the above-mentioned general formulas (ca-1) to (ca-3).

[0263] In the resist composition of this embodiment, the component (B1) may be used alone or in combination of two or more. The content of the component (B1) is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, based on 100 parts by mass of the component (A). The resist composition of this embodiment preferably contains only the component (B0) which is an acid generator.

[0264] <Other ingredients> The resist composition of this embodiment may contain other components in addition to the above-mentioned components (A) and (B). Examples of such other components include the following components (D), (E), (F), and (S).

[0265] Base component (D) The resist composition of this embodiment may also preferably contain a base component (hereinafter also referred to as "component (D)") that inhibits acid generated by exposure (i.e., inhibits acid diffusion). Component (D) in the resist composition acts as a quencher (acid diffusion inhibitor) that inhibits acid generated by exposure. Examples of component (D) include a photodisintegrating base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its acid diffusion inhibitory properties, and a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not correspond to component (D1). Of these, the photodisintegrating base (component (D1)) is preferred because it easily improves roughness reduction properties. Furthermore, the inclusion of component (D1) facilitates improvements in either high sensitivity or the suppression of coating defects.

[0266] ･About the (D1) ingredient When a resist pattern is formed by using a resist composition containing component (D1), the contrast between the exposed portion and the unexposed portion of the resist film can be further enhanced. Component (D1) is not particularly limited as long as it loses its acid diffusion inhibitory property due to decomposition upon exposure. Preferably, it is one or more compounds selected from the group consisting of compounds represented by the following general formula (d1-1) (hereinafter referred to as "component (d1-1)"), compounds represented by the following general formula (d1-2) (hereinafter referred to as "component (d1-2)"), and compounds represented by the following general formula (d1-3) (hereinafter referred to as "component (d1-3)"). Since components (d1-1) to (d1-3) decompose in the exposed portion of the resist film and lose their acid diffusion inhibitory properties (basic properties), they do not act as a quencher and are used as a quencher in the unexposed portion of the resist film.

[0267] [In the formula, Rd1-Rd4 are cyclic groups that may be substituted, chain alkyl groups that may be substituted, or chain alkenyl groups that may be substituted. However, in Rd2 in formula (d1-2), the carbon atom adjacent to the sulfur atom is not bonded to a fluorine atom. Yd1 is a single bond or a divalent linking group. m is an integer greater than 1, and Mm+ are each independently an m-valent organic cation.]

[0268] {(d1-1)Component} ･･Anion part In formula (d1-1), Rd1 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each of them is the same as R'201 above. Among these, Rd1 is preferably an aromatic hydrocarbon group which may optionally have a substituent, an aliphatic cyclic group which may optionally have a substituent, or a chain alkyl group which may optionally have a substituent. Examples of substituents that these groups may have include hydroxyl groups, pendant oxygen 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) above, ether bonds, ester bonds, or combinations thereof. When an ether bond or ester bond is included as a substituent, an alkylene bond may be interposed therebetween. In this case, the substituent is preferably a linking group represented by the formulas (y-a1) to (y-a1-5) above. Furthermore, when the aromatic hydrocarbon group, aliphatic cyclic group, or chain alkyl group in Rd1 has as a substituent a linking group represented by each of the above-mentioned general formulas (y-al-1) to (y-al-7), the carbon atom that is bonded to the aromatic hydrocarbon group, aliphatic cyclic group, or chain alkyl group in Rd1 in formula (d3-1) in the above-mentioned general formulas (y-al-1) to (y-al-7) is V'101 in the above-mentioned general formulas (y-al-1) to (y-al-7). Preferred examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure including a bicyclooctane skeleton (a polycyclic structure composed of a bicyclooctane skeleton and a ring structure other than the bicyclooctane skeleton). As the aforementioned aliphatic cyclic group, a compound selected from adamantane, Alkane, Iso More preferably, polycycloalkanes such as cyclohexane, tricyclodecane, and tetracyclododecane are obtained by removing one or more hydrogen atoms. The aforementioned chain alkyl group preferably has 1 to 10 carbon atoms, and specifically includes linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; and branched chain alkyl groups such as 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl.

[0269] When the aforementioned chain alkyl group has a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms, and even more preferably 1 to 4 carbon atoms. The fluorinated alkyl group may also contain atoms other than fluorine atoms. Examples of atoms other than fluorine atoms include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0270] Preferred specific examples of the anion portion of the component (d1-1) are shown below.

[0271]

[0272] ･･Cationic Department In formula (d1-1), M m+ is an organic cation with a valence of m. As the organic cation of M m+, the same ones as those represented by the aforementioned general formulas (ca-1) to (ca-3) are appropriately cited, with those represented by the aforementioned general formula (ca-1) being more preferred, and those represented by the aforementioned formulas (ca-1-1) to (ca-1-113) being even more preferred. The component (d1-1) may be used alone or in combination of two or more.

[0273] {(d1-2)Component} ･･Anion part In formula (d1-2), Rd2 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and examples thereof include the same as those for R'201 described above. However, in Rd2, there is no fluorine atom bonded to the carbon atom adjacent to the S atom (no fluorination substitution). This makes the anion of the (d1-2) component a moderately weak acid anion, thereby increasing the quenching energy of the (D) component. Rd 2 is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent, and more preferably an aliphatic cyclic group which may have a substituent.

[0274] The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 3 to 10 carbon atoms. The aliphatic cyclic group is a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like (which may have a substituent); more preferably, a group obtained by removing one or more hydrogen atoms from camphor.

[0275] The hydrocarbon group of Rd2 may also have a substituent, and examples of the substituent include the same substituents as those possessed by the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in Rd1 in the aforementioned formula (d1-1).

[0276] Preferred specific examples of the anion portion of the component (d1-2) are shown below.

[0277]

[0278] ･･Cationic Department In formula (d1-2), M m+ is an m-valent organic cation, which is the same as M m+ in the aforementioned formula (d1-1). The component (d1-2) may be used alone or in combination of two or more.

[0279] {(d1-3)Component} ･･Anion part In formula (d1-3), Rd3 is a cyclic group which may be substituted, a chain alkyl group which may be substituted, or a chain alkenyl group which may be substituted. Examples of the same as those for R'201 described above include cyclic groups, chain alkyl groups, or chain alkenyl groups containing fluorine atoms. Among these, a fluorinated alkyl group is preferred, and the same fluorinated alkyl group as for Rd1 described above is even more preferred.

[0280] In formula (d1-3), Rd4 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the same ones as those for R'201 are given. Among them, an alkyl group, an alkoxy group, an alkenyl group, and a cyclic group which may have a substituent are preferred. The alkyl group in Rd4 is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specific examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. Some of the hydrogen atoms in the alkyl group in Rd4 may be substituted with hydroxyl groups, cyano groups, or the like. The alkoxy group in Rd4 is preferably an alkoxy group having 1 to 5 carbon atoms. Specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, and tert-butoxy. Among them, methoxy and ethoxy are preferred.

[0281] Examples of the alkenyl group in Rd4 include the same alkenyl groups as those in R'201, preferably vinyl, propenyl (allyl), 1-methylpropenyl, and 2-methylpropenyl. These groups may further have an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms as a substituent.

[0282] The cyclic group in Rd4 is the same as the cyclic group in R'201, and is selected from cyclopentane, cyclohexane, adamantane, nor Alkane, Iso Preferred are alicyclic groups obtained by removing one or more hydrogen atoms from cycloalkanes such as cycloalkanes such as d-1-oxane, tricyclodecane, and tetracyclododecane, or aromatic groups such as phenyl and naphthyl. When Rd4 is an alicyclic group, the resist composition dissolves well in organic solvents, resulting in improved lithographic properties. Furthermore, when Rd4 is an aromatic group, the resist composition exhibits superior light absorption efficiency in lithography using EUV or other light sources, resulting in improved sensitivity and lithographic properties.

[0283] In formula (d1-3), Yd1 is a single bond or a divalent linking group. The divalent linking group in Yd1 is not particularly limited, but includes a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, a divalent linking group containing a heteroatom, and the like. These are the same as the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a heteroatom exemplified in the description of the divalent linking group in Ya21 in the above formula (a2-1). Yd1 is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is preferably a linear or branched alkylene group, and is more preferably a methylene group or an ethylene group.

[0284] Preferred specific examples of the anion portion of the component (d1-3) are shown below.

[0285]

[0286]

[0287] ･･Cationic Department In formula (d1-3), M m+ is an m-valent organic cation, which is the same as M m+ in the aforementioned formula (d1-1). The component (d1-3) may be used alone or in combination of two or more.

[0288] As the component (D1), only one of the components (d1-1) to (d1-3) may be used, or two or more of them 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 10 parts by mass, and even more preferably 2 to 8 parts by mass, relative to 100 parts by mass of component (A). If the content of component (D1) is above the preferred lower limit, particularly good lithography characteristics and resist pattern shapes can be easily obtained. On the other hand, if it is below the upper limit, sensitivity can be well maintained and throughput is also excellent.

[0289] In the resist composition of this embodiment, the component (D1) preferably includes the above-mentioned component (d1-1). In the resist composition of this embodiment, the content of the component (d1-1) is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more of the entire component (D). The component (D) may also be composed solely of the compound (d1-1).

[0290] (D1) Method of manufacturing ingredients: The production method of the components (d1-1) and (d1-2) is not particularly limited, and they can be produced by known methods. The method for producing the component (d1-3) is not particularly limited and can be produced in the same manner as the method described in, for example, US 2012-0149916.

[0291] ･About the (D2) ingredient The component (D) may contain a nitrogen-containing organic compound component (hereinafter referred to as "component (D2)") which does not correspond to the component (D1) described above. Component (D2) is not particularly limited as long as it functions as an acid diffusion inhibitor and does not correspond to component (D1), and any known component may be used. Among them, aliphatic amines are preferred, and secondary or tertiary aliphatic amines are particularly preferred. Aliphatic amine refers to an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms. Examples of the aliphatic amine include amines in which at least one of the hydrogen atoms of ammonia NH 3 is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms (alkylamines or alkylolamines) or cyclic amines. Specific examples of alkylamines and alkylolamines 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 alkylolamines 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 is particularly preferred.

[0292] Examples of cyclic amines include heterocyclic compounds containing nitrogen as a heteroatom. These heterocyclic compounds may be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines). Specific examples of the aliphatic monocyclic amine include pyridine and piperazine. The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specific examples thereof 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.

[0293] Examples of 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, and triethanolamine triacetate. Triethanolamine triacetate is preferred.

[0294] Furthermore, as the component (D2), an aromatic amine can also be used. Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole, or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and 2,6-di-tert-butylpyridine.

[0295] Among the above, component (D2) is preferably an alkylamine, more preferably a trialkylamine having 6 to 30 carbon atoms.

[0296] The component (D2) may be used alone or in combination of two or more. When the resist composition contains component (D2), the content of component (D2) in the resist composition is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of component (A). If the content of component (D2) is above the preferred lower limit, particularly good lithography characteristics and resist pattern shapes can be easily obtained. On the other hand, if it is below the upper limit, sensitivity can be well maintained and throughput is also excellent.

[0297] At least one compound (E) selected from the group consisting of organic carboxylic acids, 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, phosphorus oxyacids, and their derivatives (hereinafter referred to as "component (E)") for the purpose of preventing sensitivity deterioration or improving resist pattern shape, extending temporal stability, etc. Specific examples of the organic carboxylic acid include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid, among which salicylic acid is preferred. Examples of the phosphorus oxyacid include phosphoric acid, phosphorous acid, and phosphonic acid. Among these, phosphorous acid is particularly preferred.

[0298] In the resist composition of this embodiment, the component (E) may be used alone or in combination of two or more. 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, relative to 100 parts by mass of component (A). By setting the content within this range, lithography properties can be further improved.

[0299] Fluorine additive ingredients (F) The resist composition of this embodiment may also contain a fluorine additive component (hereinafter referred to as "component (F)") serving as a hydrophobic resin. Component (F) is used to impart water repellency to the resist film. By using it as a resin distinct from component (A), it can enhance lithography properties. As the component (F), for example, fluorine-containing polymer compounds described in JP-A-2010-002870, JP-A-2010-032994, JP-A-2010-277043, JP-A-2011-13569, and JP-A-2011-128226 can be used. More specifically, component (F) includes a polymer having a structural unit (f1) represented by the following general formula (f1-1). This polymer includes a polymer (homopolymer) containing only the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) and the aforementioned structural unit (a1); preferably, a copolymer of the structural unit (f1) with a structural unit derived from acrylic acid or methacrylic acid and the aforementioned structural unit (a1); and more preferably, a copolymer of the structural unit (f1) with the aforementioned structural unit (a1). The structural unit (a1) copolymerized with the structural unit (f1) is preferably a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate, a structural unit derived from 1-methyl-1-adamantane (meth)acrylate, and more preferably, a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate.

[0300] [In the formula, R is the same as described above, Rf102 and Rf103 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf102 and Rf103 may be the same or different. nf1 is an integer from 0 to 5, and Rf101 is an organic group containing a fluorine atom.]

[0301] In formula (f1-1), R bonded to the α-carbon atom is the same as described above. R is preferably a hydrogen atom or a methyl group. In formula (f1-1), the halogen atom for Rf102 and Rf103 is preferably a fluorine atom. Examples of the alkyl group having 1 to 5 carbon atoms for Rf102 and Rf103 include the same as the alkyl group having 1 to 5 carbon atoms described above for R, and preferably a methyl group or an ethyl group. Specifically, examples of the halogenated alkyl group having 1 to 5 carbon atoms for Rf102 and Rf103 include groups in which some or all of the hydrogen atoms in the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. The halogen atom is preferably a fluorine atom. Among them, Rf102 and Rf103 are preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom. In formula (f1-1), nf1 is an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.

[0302] In formula (f1-1), Rf101 is an organic group containing a fluorine atom, 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 preferred that more than 25% of the hydrogen atoms in the hydrocarbon group containing fluorine atoms be fluorinated, more preferably more than 50% be fluorinated, and particularly preferably more than 60% be fluorinated in order to improve the hydrophobicity of the resist film during immersion exposure. Among them, Rf101 is preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, and is particularly preferably trifluoromethyl, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, or -CH2-CH2-CF2-CF2-CF2-CF3.

[0303] The weight-average molecular weight (Mw) of component (F) (based on polystyrene conversion as determined by gel permeation chromatography) is preferably 1,000-50,000, more preferably 5,000-40,000, and most preferably 10,000-30,000. If the Mw is below the upper limit of this range, the resist has sufficient solubility in the resist solvent when used as a resist. If the Mw is above the lower limit of this range, the water repellency of the resist film is improved. The dispersion degree (Mw / Mn) of the (F) component is preferably 1.0-5.0, more preferably 1.0-3.0, and most preferably 1.0-2.5.

[0304] In the resist composition of this embodiment, the component (F) may be used alone or in combination of two or more. When the resist composition contains component (F), the content of component (F) is preferably 0.5 to 10 parts by mass, more preferably 1 to 10 parts by mass, based on 100 parts by mass of component (A).

[0305] Organic solvent component (S) The resist composition of this embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as "(S) component"). The component (S) may be any solvent capable of dissolving the components to be used and forming a uniform solution, and any solvent conventionally known as a solvent for a chemically amplified resist composition may be appropriately selected and used. Component (S) includes, for example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-amyl ketone, methyl isoamyl ketone, and 2-heptanone; polyols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; derivatives of polyols such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, or monophenyl ether of the aforementioned polyols or compounds having an ester bond. [Preferably propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME); cyclic ethers such as dioxane, or esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenethyl ether, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, isopropyltoluene, and mesitylene; and dimethyl sulfoxide (DMSO). In the resist composition of this embodiment, component (S) may be used alone or as a mixture of two or more solvents. Among them, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0306] Component (S) is preferably a mixture of PGMEA and a polar solvent. The mixing ratio (mass ratio) can be appropriately determined by considering the compatibility of PGMEA and the polar solvent, and is preferably within the range of 1:9 to 9:1, and more preferably within the range of 2:8 to 8:2. More specifically, when blending EL or cyclohexanone as a polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9-9:1, more preferably 2:8-8:2. Furthermore, when blending PGME as a polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9-9:1, more preferably 2:8-8:2, and even more preferably 3:7-7:3. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is preferred. Furthermore, as component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferred. In this case, the mixing ratio of the former to the latter is preferably 70:30 to 95:5 by weight. The amount of component (S) used is not particularly limited and is appropriately set to a concentration that allows coating on a substrate, etc., and in accordance with the coating film thickness. Generally, component (S) is used to achieve a solids concentration in the resist composition within a range of 0.1-20% by mass, preferably 0.2-15% by mass.

[0307] The resist composition of this embodiment can also be prepared by dissolving the resist material in component (S) and then removing impurities using a porous polyimide membrane, a porous polyamideimide membrane, or the like. For example, the resist composition can be filtered using a filter comprising a porous polyimide membrane, a filter comprising a porous polyamideimide membrane, or a filter comprising a porous polyimide membrane and a porous polyamideimide membrane. Examples of the porous polyimide membrane and the porous polyamideimide membrane include those described in Japanese Patent Application Laid-Open No. 2016-155121.

[0308] The resist composition of the present embodiment described above contains a base component (A) and an acid generator component (B), and the acid generator component (B) includes a compound (B0) represented by the general formula (b0). Since compound (B0) has multiple iodine atoms, it has a higher absorption efficiency of EUV (extreme ultraviolet) and EB (electron beam). Furthermore, since compound (B0) has a phenylene group having two or more iodine atoms and an arylene group or heteroarylene group having one or more iodine atoms, the diffusion length of the acid can be appropriately suppressed. Furthermore, since compound (B0) has a phenylene group having two or more iodine atoms at a position relatively close to the sulfonic acid anion, the acidity of the acid generated from compound (B0) is increased. Due to this synergistic effect, compound (B0) can generate a larger amount of acid in the exposed portion of the resist film than conventional acid generators, and can also reduce the amount of acid that diffuses from the exposed portion of the resist film to the unexposed portion. Therefore, the resist composition of this embodiment containing compound (B0) is expected to achieve high sensitivity and form a resist pattern with good roughness reduction.

[0309] (Resist Pattern Formation Method) The resist pattern forming method related to the second type of the present invention comprises the steps of forming a resist film on a support using the resist composition related to the first type of the present invention, exposing the resist film, and developing the exposed resist film to form a resist pattern. As one embodiment of the related resist pattern forming method, there is a resist pattern forming method performed as follows.

[0310] First, the resist composition of the above embodiment is coated on a support using a spinner or the like, and a baking (post-application baking (PAB)) treatment is applied at a temperature of, for example, 80-150° C. for 40-120 seconds, preferably 60-90 seconds, to form a resist film. Next, the resist film is subjected to selective exposure such as exposure through a mask (mask pattern) having a specific pattern formed thereon, or direct electron beam irradiation without using a mask pattern, using an exposure device such as an electron beam drawing device or an ArF exposure device. The resist film is then baked (post-exposure bake (PEB)) at a temperature of, for example, 80 to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds. Next, the resist film is developed. When the development is an alkaline development process, an alkaline developer is used. When the development is a solvent development process, an organic solvent-containing developer (organic developer) is used.

[0311] After the development process, it is preferred to perform a cleaning process. When the cleaning process is an alkaline development process, it is preferred to use pure water for cleaning, and when the cleaning process is a solvent development process, it is preferred to use a cleaning solution containing an organic solvent. In the solvent development process, after the aforementioned development or cleaning process, a process of removing the developer or cleaning solution attached to the pattern by using a supercritical fluid may be performed. After developing or washing, drying is performed. Depending on the situation, baking (post-baking) may also be performed after the above-mentioned developing process. In this way, a resist pattern can be formed.

[0312] The support is not particularly limited, and conventionally known materials can be used. Examples include substrates for electronic components, or substrates on which a specific wiring pattern is formed. More specifically, examples include silicon wafers, substrates made of metals such as copper, chromium, iron, and aluminum, or glass substrates. Materials for the wiring pattern include copper, aluminum, nickel, and gold.

[0313] The wavelength used for exposure is not particularly limited; exposure can be performed using radiation such as ArF excimer lasers, KrF excimer lasers, F2 excimer lasers, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beams), X-rays, and soft X-rays. The resist composition is particularly useful for exposure to KrF excimer lasers, ArF excimer lasers, EB, or EUV, and even more so for ArF excimer lasers, EB, or EUV, with particularly high usefulness for EB or EUV. In other words, the resist patterning method of this embodiment is particularly useful when the step of exposing the resist film includes exposing the resist film to EUV (extreme ultraviolet) or EB (electron beams).

[0314] The exposure method of the resist film can be general exposure (dry exposure) performed in an inert gas such as air or nitrogen, or liquid immersion lithography. Immersion exposure is an exposure method in which the space between the resist film and the lowest lens of the exposure device is filled with a solvent (immersion solvent) having a refractive index greater than that of air, and exposure is performed in this state (immersion exposure). As the immersion solvent, a solvent having a refractive index greater than that of air and smaller than that of the exposed resist film is preferred, such as water, fluorine-based inert liquid, silicon-based solvent, hydrocarbon-based solvent, etc. As the immersion solvent, water is preferably used.

[0315] As an alkaline developer used in the developing treatment in the alkaline developing process, there is, for example, a 0.1-10 mass % tetramethylammonium hydroxide (TMAH) aqueous solution. The organic solvent contained in the organic developer used in the solvent development process can be any solvent capable of dissolving component (A) (component (A) before exposure) and can be appropriately selected from known organic solvents. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents, are exemplified.

[0316] Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl 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 butyrate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobyrate, and butyl propionate.

[0317] Examples of the nitrile solvent include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0318] Known additives may be added to the organic developer as needed. Examples of such additives include surfactants. The surfactant is not particularly limited, but examples thereof include ionic or nonionic fluorinated and / or silicone surfactants. Nonionic surfactants are preferred, with nonionic fluorinated or nonionic silicone surfactants being even more preferred. When a surfactant is added, its amount is generally 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass, relative to the total amount of the organic developer.

[0319] The developing process can be carried out by a known developing method, for example, a method of immersing the support in the developer for a certain period of time (immersion method), a method of raising the developer on the surface of the support for a certain period of time and allowing it to remain stationary by utilizing surface tension (stirring method), a method of spraying the developer onto the surface of the support (spraying method), a method of continuously applying the developer while scanning the developer coating nozzle at a certain speed on a support rotating at a certain speed (dynamic implementation method), etc.

[0320] The organic solvent contained in the cleaning solution used for the post-development cleaning process in the solvent development process can be appropriately selected from the organic solvents listed above for the organic developer, for example, one that is difficult to dissolve the resist pattern. Typically, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents is used. Among these solvents, at least one selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, and amide solvents is preferred, and at least one selected from alcohol solvents and ester solvents is even more preferred. Alcohol solvents are particularly preferred. The alcohol solvent used in the cleaning solution is preferably a monohydric alcohol having 6 to 8 carbon atoms. This monohydric alcohol may be linear, branched, or cyclic. Specifically, examples include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferred, with 1-hexanol and 2-hexanol being even more preferred. Any of these organic solvents may be used alone or in combination of two or more. Furthermore, organic solvents other than those listed above or water may be mixed. However, considering the development characteristics, the amount of water in the cleaning solution is preferably 30% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less, relative to the total amount of the cleaning solution. The cleaning solution may be mixed with known additives as needed. Examples of such additives include surfactants. Examples of surfactants include the same surfactants as those mentioned above, with nonionic surfactants being preferred, and nonionic fluorinated surfactants or nonionic silicone surfactants being even more preferred. When a surfactant is added, its amount is generally 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass relative to the total amount of the cleaning solution.

[0321] The cleaning process (cleaning process) using a cleaning liquid can be carried out using a known cleaning method. Examples of such cleaning methods include continuously coating the cleaning liquid onto a support rotating at a constant speed (spin coating method), immersing the support in the cleaning liquid for a predetermined period of time (immersion method), and spraying the cleaning liquid onto the support surface (spray method).

[0322] As described above, the resist pattern forming method of this embodiment uses the resist composition, so that a resist pattern with high sensitivity and good roughness reduction can be formed.

[0323] The resist composition of the above-described embodiment and the various materials used in the patterning method of the above-described embodiment (e.g., resist solvent, developer, cleaning solution, anti-reflective film-forming composition, topcoat layer-forming composition, etc.) preferably do not contain impurities such as metals, halogen-containing metal salts, acids, bases, or components containing sulfur or phosphorus atoms. Examples of impurities containing metal atoms include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The impurity content of these materials is preferably 200 ppb or less, more preferably 1 ppb or less, even more preferably 100 ppt (parts per trillion) or less, and particularly preferably 10 ppt or less. It is most preferable that the impurities are substantially absent (below the detection limit of the measuring device).

[0324] (Compound) The compound related to the third embodiment of the present invention is a compound represented by the following general formula (b0).

[0325] [wherein, Ar is an arylene group or a heteroarylene group, R and R are each independently a substituent other than an iodine atom, L is a divalent linking group or a single bond, L is a divalent linking group, V is a single bond, an alkylene group, or a fluorinated alkylene group, R is a hydrogen atom, a fluorinated alkylene group having 1 to 5 carbon atoms, or a fluorine atom, n is an integer from 2 to 4, n is an integer from 1 to 3, n is an integer from 0 to 2, n is an integer of 0 or greater, n is an integer of 1 or greater, M represents an m-valent organic cation, and m is an integer of 1 or greater]

[0326] The compound represented by the general formula (b0) is the same as the component (B0) in the resist composition related to the first embodiment of the present invention.

[0327] [Method for producing the compound represented by general formula (b0)] The component (B0) can be prepared using a known method. For example, component (B0) can be obtained by a salt exchange reaction between a precursor Bpre represented by the following general formula (Bpre) and a compound S0 represented by the following general formula (S-0).

[0328] [In the formula, Ar is an aryl group or heteroaryl group, R and R are hydroxyl, alkyl, fluorinated alkyl, fluorine, or chlorine. L is a divalent linking group or a single bond, L is a divalent linking group, V is a single bond, an alkyl group or a fluorinated alkyl group, R is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom, n is an integer from 2 to 4, n is an integer from 1 to 3, n is an integer from 0 to 2, n is an integer from 0 or greater, and n is an integer from 1 or greater. (M 1" m+) 1 / m represents an ammonium cation. Z is a non-nuclear ion. M represents an m-valent organic cation, and m is an integer from 1 or greater.]

[0329] More specifically, the salt exchange reaction is a step of reacting the precursor Bpre with the salt exchange compound S0 in a solvent such as water, dichloromethane, acetonitrile, or chloroform, and exchanging the cation of the precursor Bpre with the cation of the compound S0 to obtain the component (B0).

[0330] In the above formula, (M 1″ m+) 1 / m is an ammonium cation, and the ammonium cation may be an ammonium cation derived from an aliphatic amine or an ammonium cation derived from an aromatic amine.

[0331] In the above formula, Z- includes ions that can become an acid with lower acidity than the precursor Bpre, specifically, halogen ions such as bromide ion and chloride ion, BF4-, AsF6-, SbF6-, PF6-, ClO4-, etc.

[0332] The reaction temperature is, for example, 0 to 100° C., and the reaction time is, for example, 10 minutes to 24 hours.

[0333] After the salt exchange reaction is completed, the compound in the reaction solution can be isolated and purified. For isolation and purification, conventionally known methods can be used, such as concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography, etc., which can be appropriately combined. The structure of the compound obtained as described above can be identified by general organic analysis methods such as 1H-nuclear magnetic resonance (NMR) spectroscopy, 13C-NMR spectroscopy, 19F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass spectrometry (MS), elemental analysis, and X-ray crystallography.

[0334] The raw materials used in each step may be commercially available or synthesized. For example, as a method for producing the precursor Bpre, there are the following methods 1 for producing the precursor Bpre and 2 for producing the precursor Bpre.

[0335] [Method 1 for producing precursor Bpre] Method 1 for producing a precursor Bpre comprises: a step (step 1) of reacting a compound represented by the following general formula (CA-0) (hereinafter referred to as "compound (CA0)") with a compound represented by the following general formula (I-0) (hereinafter referred to as "compound (I0)") to obtain a compound represented by the following general formula (Y-0) (hereinafter referred to as "compound (Y0)"), and a step (step 2) of reacting the compound represented by the following general formula (Y-0) with a compound represented by the following general formula (X-0) (hereinafter referred to as "compound (X0)") to obtain a precursor Bpre represented by the following general formula (Bpre).

[0336] [In the formula, Ar is an arylene group or a heteroarylene group, R and R are a hydroxyl group, an alkyl group, a fluorinated alkyl group, a fluorine atom, or a chlorine atom. L is a divalent linking group or a single bond, L is a divalent linking group, V is a single bond, an alkyl group, or a fluorinated alkyl group, R is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom, n is an integer from 2 to 4, n is an integer from 1 to 3, n is an integer from 0 to 2, n is an integer of 0 or greater, and n is an integer of 1 or greater. (M 1″ m+) 1 / m is an ammonium cation. a and b are groups that react to form L. a and b are groups that react to form L.]

[0337] Step 1: The first step is a step of reacting compound (CA0) with compound (I0) in an organic solvent (such as acetonitrile) to obtain compound (Y0).

[0338] In the first step, a condensation agent, a basic catalyst, etc. may also be used. Specific examples of the condensing agent include N,N'-dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, and carbonyldiimidazole (CDI). Specific examples of the basic catalyst include tertiary amines such as trimethylamine, triethylamine, and tributylamine, aromatic amines such as pyridine, dimethylaminopyridine (DMAP), and pyrrolidinylpyridine, diazabicyclononene (DBN), and diazabicycloundecene (DBU).

[0339] The reaction temperature of the first step is, for example, 0-50° C., and the reaction time is, for example, 10 minutes to 24 hours.

[0340] a1 and b1 are groups that react to form L 01. When L01 is an ester bond, in the formula, one of a1 and b1 is a hydroxyl group, and the other is a carboxyl group.

[0341] a2 and b2 are groups that react to form L 02. When L02 is an ester bond, in the formula, one of a2 and b2 is a hydroxyl group and the other is a carboxyl group.

[0342] Step 2: The second step is a step of reacting compound (Y0) with compound (X0) in an organic solvent (such as acetonitrile) to obtain a precursor Bpre.

[0343] In the second step, similarly to the first step, a condensation agent, a basic catalyst, etc. may also be used. The reaction temperature of the second step is, for example, 0-50° C., and the reaction time is, for example, 10 minutes to 24 hours.

[0344] [Method 2 for producing precursor Bpre] The manufacturing method 1 of the precursor Bpre comprises: A step (step A) of reacting a compound represented by the following general formula (CA-00) (hereinafter referred to as "compound (CA00)") with a compound represented by the following general formula (X-00) (hereinafter referred to as "compound (X00)") to obtain a compound represented by the following general formula (Y-00) (hereinafter referred to as "compound (Y00)"), and A step of reacting a compound represented by the following general formula (Y-00) with a compound represented by the following general formula (Al-00) (hereinafter referred to as "compound (Al00)") to obtain a precursor Bpre' represented by the following general formula (Bpre') (step B). The precursor Bpre' is a compound used to obtain the compound (B0). In the general formula (b0), L01 and L02 are defined as ester bonds.

[0345] [In the formula, Ar is an aryl group or a heteroaryl group, R and R are a hydroxyl group, an alkyl group, a fluorinated alkyl group, a fluorine atom, or a chlorine atom. V is a single bond, an alkyl group, or a fluorinated alkyl group, R is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom, n is an integer from 2 to 4, n is an integer from 1 to 3, n is an integer from 0 to 2, n is an integer from 0 or greater, and n is an integer from 1 or greater. (M 1″ m+) 1 / m represents an ammonium cation.]

[0346] Step A: Step A is a step of, for example, dissolving compound (CA00) and compound (X00) in an organic solvent (THF, hexane, etc.) and reacting them in the presence of a base to obtain compound (Y00).

[0347] Specific examples of the base include sodium hydride, K 2 CO 3 , Cs 2 CO 3 , lithium diisopropylamide (LDA), triethylamine, and 4-dimethylaminopyridine. The reaction temperature is, for example, 0 to 50° C., and the reaction time is, for example, 10 minutes to 24 hours.

[0348] Step B: Step B is a step of reacting compound (Y00) with compound (A100) in an organic solvent (such as dichloromethane) to obtain a precursor Bpre'.

[0349] In step B, a condensation agent, a basic catalyst, etc. may also be used. Specific examples of the condensing agent include N,N'-dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, and carbonyldiimidazole (CDI). Specific examples of the basic catalyst include tertiary amines such as trimethylamine, triethylamine, and tributylamine, aromatic amines such as pyridine, dimethylaminopyridine (DMAP), and pyrrolidinylpyridine, diazabicyclononene (DBN), and diazabicycloundecene (DBU).

[0350] The reaction temperature of step B is, for example, 0-50° C., and the reaction time is, for example, 10 minutes or more and 24 hours or less.

[0351] The compound related to the third aspect of the present invention described above is a useful compound as an acid generator in the resist composition related to the first aspect of the present invention.

[0352] (Acid Generator) The acid generator related to the fourth embodiment of the present invention includes the compound related to the third embodiment. Such acid generators are useful as acid generator components for chemically amplified resist compositions. By using such acid generator components in chemically amplified resist compositions, high sensitivity can be achieved and roughness reduction can be enhanced during resist patterning. The use of such acid generator components, particularly in resist patterning using EB or EUV light sources, allows for high sensitivity and improved roughness reduction. [Example]

[0353] Hereinafter, the present invention will be described in further detail with reference to examples, but the present invention is not limited to these examples.

[0354] <Synthesis Example of Compound> [Synthesis Example of Intermediate Product] ･Synthesis of intermediate 1 In a 300 mL three-necked flask, 1,1'-carbonyldiimidazole (CDI) (4.60 g, 28.4 mmol) and acetonitrile (20 g) were placed. 3,5-Diiodosalicylic acid (CA1) (10.0 g, 25.5 mmol) dissolved in acetonitrile (20 g) was added dropwise over 30 minutes and allowed to react for 1 hour. Compound (I-1) (9.5 g, 30.6 mmol) was then added and allowed to react at 65°C for 3 hours. After cooling, ultrapure water (250 g) was added, and after stirring for 30 minutes, the precipitated solid was filtered. The filtrate was redissolved in methanol (100 g), MTBE (500 g) was added dropwise, and the precipitated solid was filtered. The filtrate was dried under reduced pressure to obtain Intermediate 1.

[0355]

[0356] ･Synthesis of intermediates 2~6 Intermediates 2 to 6 were synthesized in the same manner as in the synthesis of intermediate 1, except that 3,5-diiodosalicylic acid (CA1) (10.0 g, 25.5 mmol) was replaced with an equal molar amount of the carboxylic acid of any of the following CA2 to CA6.

[0357]

[0358]

[0359] ･Synthesis of Intermediate 7 A 1.06M solution of lithium diisopropylamide (LDA) in THF / hexane (87 ml, 92.3 mmol) was placed in a 500 mL three-necked flask. After cooling to 5°C, 4-iodinated phenol (10.1 g, 46.0 mmol) dissolved in THF (30 g) was added and the mixture was reacted at or below 5°C for 2 hours. Next, tetraiodinated phthalic anhydride (15.0 g, 23.0 mmol) dissolved in THF (150 g) was added and the mixture was reacted at or below 5°C for 2 hours. The reaction mixture was poured into ultrapure water (205 g) over 30 minutes, followed by the addition of heptane (205 g). After stirring for 30 minutes, the organic layer was removed. The aqueous layer was washed three times with heptane (100 g), followed by the addition of MTBE (150 g) and a 10% aqueous citric acid solution (86.5 g, 45.0 mmol). After stirring for 30 minutes, the aqueous layer was removed. The recovered organic layer was washed three times with ultrapure water (150 g), concentrated using a rotary evaporator, and recrystallized from ethyl acetate to obtain intermediate 7.

[0360]

[0361] ･Synthesis of Intermediate 8 Intermediate 8 was obtained in the same manner as in the synthesis of Intermediate 7, except that 4-iodinated phenol (10.1 g, 46.0 mmol) was replaced with 3,5-diiodinated phenol (15.9 g, 25.5 mmol).

[0362]

[0363] ･Synthesis of Intermediate 9 Intermediate product 9 was obtained in the same manner as in the synthesis example of intermediate product 7, except that 4-iodinated phenol (10.1 g, 46.0 mmol) was replaced with 2,4,6-triiodinated phenol (21.7 g, 25.5 mmol).

[0364]

[0365] ･Synthesis of Intermediate 10 Intermediate 10 was obtained in the same manner as in the synthesis example of intermediate 1, except that compound (I-1) (9.5 g, 30.6 mmol) was replaced with compound (I-2) (11.6 g, 30.6 mmol).

[0366]

[0367] ･Synthesis of intermediate 11 Intermediate 11 was obtained in the same manner as in the synthesis example of intermediate 1, except that 3,5-diiodosalicylic acid (10.0 g, 25.6 mmol) was changed to 2,5-diiodosalicylic acid (10.0 g, 25.5 mmol) and compound (I-1) (9.5 g, 30.6 mmol) was changed to compound (I-3) (11.5 g, 30.6 mmol).

[0368]

[0369] ･Synthesis of Intermediate 12 Intermediate 12 was obtained in the same manner as in the synthesis example of intermediate 1, except that 3,5-diiodosalicylic acid (10.0 g, 25.6 mmol) was changed to 2,5-diiodosalicylic acid (10.0 g, 25.5 mmol) and compound (I-1) (9.5 g, 30.6 mmol) was changed to compound (I-4) (11.0 g, 30.6 mmol).

[0370]

[0371] [Synthesis Example of Precursor] ･Synthesis of precursor (Bpre-01) In a 300 mL three-necked flask, 4-iodobenzoic acid (CA7) (4.0 g, 16.1 mmol), intermediate 1 (9.9 g, 14.5 mmol), and dichloromethane (180 g) were placed and stirred at room temperature to dissolve. Next, diisopropylcarbodiimide (DIC) (3.1 g, 24.2 mmol) and dimethylaminopyridine (0.2 g, 1.6 mmol) were added and reacted at room temperature for 5 hours. The reaction mixture was filtered, and the filtrate was concentrated using a rotary evaporator. The concentrate was dissolved in acetonitrile (30 g), and MTBE (180 g) was added dropwise. The precipitated solid was filtered. The filtrate was again dissolved in acetonitrile (60 g), added dropwise to MTBE (400 g), and the precipitated solid was filtered. This process was repeated twice, and the filtrate was dried under reduced pressure to obtain the precursor (Bpre-01).

[0372]

[0373] Synthesis of precursors (Bpre-02)~(Bpre-13), (Bpre-17)~(Bpre-19) Except for changing the combination of carboxylic acid and intermediate product, the synthesis of precursors (Bpre-02) to (Bpre-13) and (Bpre-17) to (Bpre-19) was carried out in the same manner as the synthesis of precursor (Bpre-01). The combinations of carboxylic acids and intermediates used to obtain various precursors are shown in Table 1.

[0374]

[0375]

[0376]

[0377]

[0378] ･Synthesis of precursor (Bpre-14) In a 300 mL three-necked flask, intermediate product 7 (10.4 g, 12.1 mmol), compound (I-1) (3.4 g, 10.9 mmol), and dichloromethane (180 g) were placed and stirred at room temperature to dissolve. Next, diisopropylcarbodiimide (DIC) (2.3 g, 18.2 mmol) and dimethylaminopyridine (0.2 g, 1.6 mmol) were added and reacted at room temperature for 5 hours. The reaction mixture was filtered, and the filtrate was concentrated using a rotary evaporator. The concentrate was dissolved in acetonitrile (30 g), and MTBE (180 g) was added dropwise. The precipitated solid was filtered. The filtrate was again dissolved in acetonitrile (60 g), added dropwise to MTBE (400 g), and the precipitated solid was filtered. This process was repeated twice, and the filtrate was dried under reduced pressure to obtain the precursor (Bpre-14).

[0379]

[0380] Synthesis of precursor (Bpre-15) and precursor (Bpre-16) The precursor (Bpre-15) was obtained in the same manner as the synthesis example of the precursor (Bpre-14) except that the intermediate product 7 (10.4 g, 12.1 mmol) was replaced with an equal mol of the intermediate product 8. Furthermore, except that the intermediate product 7 (10.4 g, 12.1 mmol) was replaced with an equal mol of the intermediate product 9, the rest of the synthesis was similar to that of the precursor (Bpre-14) to obtain the precursors (Bpre-15) and (Bpre-16).

[0381]

[0382] [Synthesis Example of Compound (B0)] ･Synthesis of compound (B0-1) The precursor (Bpre-01) (10.0 g, 10.9 mmol) and salt-exchange compound A (3.93 g, 11.5 mmol) were dissolved in dichloromethane (120 g). Ultrapure water (120 g) was added and the mixture was reacted at room temperature for 30 minutes. After the reaction, the aqueous phase was removed, and the organic phase was washed four times with ultrapure water (120 g). The organic phase was concentrated to dryness using a rotary evaporator to obtain compound (B0-1).

[0383]

[0384] ･Synthesis of compounds (B0-2)~(B0-22) Compounds (B0-2) to (B0-22) were obtained in the same manner as in the "Synthesis Example of Compound (B0-1)" above, except that the above-mentioned precursors (Bpre-01) to (Bpre-19) were combined with the following salt exchange compounds A to D. Each of the obtained compounds was subjected to NMR measurement, and its structure was identified from the following analysis results.

[0385]

[0386]

[0387]

[0388]

[0389] Compound (B0-1): Combination of precursor (Bpre-01) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=7.99(d, I-ArH, 1H), 7.73-7.90(m, ArH, I-ArH, 20H), 4.81-4.88(m,CF 2CH 2,2H)

[0390] Compound (B0-2): Combination of precursor (Bpre-02) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 19H), 4.81-4.88(m, CF 2CH 2, 2H)

[0391] Compound (B0-3): Combination of precursor (Bpre-03) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 19H), 4.81-4.88(m, CF 2CH 2, 2H)

[0392] Compound (B0-4): Combination of precursor (Bpre-04) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH, 1H), 7.99(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 17H), 4.81-4.88(m, CF 2CH 2, 2H)

[0393] Compound (B0-5): Combination of precursor (Bpre-05) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 17H), 4.81-4.88(m, CF 2CH 2, 2H)

[0394] Compound (B0-6): Combination of precursor (Bpre-06) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=7.99(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH.16H), 4.81-4.88(m, CF 2CH 2, 2H)

[0395] Compound (B0-7): Combination of precursor (Bpre-07) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.12(d, I-ArH, 1H), 7.73-7.90(m, ArH, I-ArH, 19H), 4.81-4.88(m, CF 2CH 2, 2H)

[0396] Compound (B0-8): Combination of precursor (Bpre-08) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.12(d, I-ArH, 1H), 8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 17H), 4.81-4.88(m, CF 2CH 2, 2H)

[0397] Compound (B0-9): Combination of precursor (Bpre-09) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH, 1H), 8.12(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 16H), 4.81-4.88(m, CF 2CH 2, 2H)

[0398] Compound (B0-10): Combination of precursor (Bpre-10) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.12(d, I-ArH, 1H), 8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, 15H), 4.81-4.88(m, CF 2CH 2, 2H)

[0399] Compound (B0-11): Combination of precursor (Bpre-11) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.12(d, I-ArH, 1H), 7.74-7.90(m, ArH, 15H), 4.81-4.88(m, CF 2CH 2, 2H)

[0400] Compound (B0-12): Combination of precursor (Bpre-12) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=9.48(s, NH, 1H), 8.35(d, I-ArH, 1H), 7.74-7.90(m, ArH, 15H), 4.81-4.88(m, CF 2CH 2, 2H)

[0401] Compound (B0-13): Combination of precursor (Bpre-13) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=9.48(s, NH, 2H), 7.74-7.90(m, ArH, I-ArH19H), 4.81-4.88(m, CF 2CH 2, 2H)

[0402] Compound (B0-14): Combination of precursor (Bpre-14) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=7.74-7.90(m, ArH, 15H), 7.57(d, I-ArH, 2H), 6.73(d, I-ArH, 2H), 4.81-4.88(m, CF 2CH 2, 2H)

[0403] Compound (B0-15): Combination of precursor (Bpre-15) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.05(d, I-ArH, 1H), 7.74-7.90(m, ArH, 15H), 6.84(d, I-ArH, 2H), 4.81-4.88(m, CF 2CH 2, 2H)

[0404] Compound (B0-16): Combination of precursor (Bpre-16) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=7.99(d, I-ArH, 2H), 7.74-7.90(m, ArH, 15H), 4.81-4.88(m, CF 2CH 2, 2H)

[0405] Compound (B0-17): Combination of precursor (Bpre-17) and salt exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH, 1H), 7.99(d, I-ArH, 1H), 7.74-7.90(m, ArH, I-ArH, 17H), 5.93(m, CFCH, 1H)

[0406] Compound (B0-18): Combination of precursor (Bpre-18) and salt exchange compound A 1H-NMR (DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH1H), 7.74-7.90(m, ArH, I-ArH, 18H), 4.05-4.25(m, COO-“CH 2”CH 2-, 2H), 2.63-2.73(m, COOCH 2“CH 2”, 2H)

[0407] Compound (B0-19): Combination of prodrug (Bpre-19) and salt-exchange compound A 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH1H), 7.74-7.90(m, ArH, I-ArH, 18H), 4.91-5.20(m, CFCH, 1H), 3.95-4.20(m, COO-“CH 2”CH 2-, 2H), 2.30-2.45(m, COOCH 2"CH 2", 1H), 1.61-1.72(m, COOCH 2"CH 2", 1H)

[0408] Compound (B0-20): Combination of prodrug (Bpre-17) and salt-exchange compound B 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH, 1H), 7.70-8.22(m, ArH, I-ArH, 17H), 5.93(m, CFCH, 1H), 3.30-3.45(m, SO 2CH, 1H), 1.09-1.90(m, Cyclohexyl, 10H)

[0409] Compound (B0-21): Combination of procatalyst (Bpre-17) and salt-exchange compound C 1H-NMR(DMSO, 400MHz): δ(ppm)=8.34(d, I-ArH, 1H), 7.99(d, I-ArH, 1H), 7.77-7.98(m, ArH, I-ArH13H), 5.93(m, CFCH, 1H)

[0410] Compound (B0-22): Combination of procatalyst (Bpre-17) and salt-exchange compound D 1H-NMR(DMSO, 400MHz): δ(ppm)=8.50(d, ArH, 2H), 8.37(d, ArH, 2H), 8.34(d, I-ArH, 1H), 7.99(d, I-ArH, 1H), 7.93(t, ArH, 2H), 7.84(d, I-ArH, 1H), 7.76(d, I-ArH, 1H), 7.55-7.75(m, ArH, 7H), 5.93(m, CFCH, 1H)

[0411] <Preparation of Resist Composition> (Examples 1 to 27, Comparative Examples 1 to 5) The components shown in Tables 2 to 6 were mixed and dissolved to prepare the resist compositions of each example.

[0412]

[0413]

[0414]

[0415]

[0416]

[0417] In Tables 2 to 6, the abbreviations have the following meanings. The values ​​in parentheses are the blending amounts (parts by mass).

[0418] (A)-1: A polymer compound represented by the following chemical formula (A-1). The weight-average molecular weight (Mw) of this polymer compound (A-1) measured by GPC, as measured based on standard polyethylene, was 6100, and the molecular weight dispersion (Mw / Mn) was 1.65. The copolymer composition ratio (the ratio (molar ratio) of the constituent units in the structural formula) determined by 13C-NMR was l / m = 50 / 50.

[0419] (A)-2: A polymer compound represented by the following chemical formula (A-2). The weight-average molecular weight (Mw) of this polymer compound (A-2) measured by GPC, as converted to standard polyethylene, was 6300, and the molecular weight dispersion (Mw / Mn) was 1.67. The copolymer composition ratio (the ratio (molar ratio) of the constituent units in the structural formula) determined by 13C-NMR was l / m = 50 / 50.

[0420] (A)-3: A polymer compound represented by the following chemical formula (A-3). The weight-average molecular weight (Mw) of this polymer compound (A-3) measured by GPC, in terms of standard polyethylene, was 6100, and the molecular weight dispersion (Mw / Mn) was 1.69. The copolymer composition ratio (the ratio (molar ratio) of the constituent units in the structural formula) determined by 13C-NMR was l / m = 50 / 50.

[0421]

[0422] (B0)-1 to (B0)-22: Acid generators each comprising the above-mentioned compounds (B0-1) to (B0-22).

[0423] (B1)-1: An acid generator comprising the following compound (B-1). (B1)-2: An acid generator comprising the following compound (B-2). (B1)-3: An acid generator comprising the following compound (B-3). (D)-1: An acid diffusion inhibitor comprising the following compound (D-1). (S)-1: A mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 / 40 (mass ratio).

[0424]

[0425] <Formation of Resist Pattern> The resist compositions of each example were applied to an 8-inch silane substrate treated with hexamethyldisilazane (HMDS) using a spinner, and pre-baked (PAB) on a hot plate at 110°C for 60 seconds. The resulting film was then dried to form a 50 nm thick resist film. Next, the resist film was exposed using an electron beam lithography system (JEOL-JBX-9300FS, manufactured by JEOL Ltd.) at an accelerating voltage of 100 kV, with a 1:1 line-to-line pattern (hereinafter referred to as "LS pattern") having a target size of 35 nm. This was followed by a post-exposure bake (PEB) treatment at 110°C for 60 seconds. 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.). Afterwards, pure water was used for 15 seconds to rinse the surface, resulting in a 1:1 LS pattern with a line width of 35 nm and a pitch of 70 nm.

[0426] [Evaluation of Optimum Exposure (Eop)] The optimum exposure dose Eop (μC / cm 2 ) for forming an LS pattern of the target size was determined using the above-mentioned "Resist Pattern Formation". This is shown in Tables 7 to 10 as "Eop (μC / cm 2)".

[0427] [Evaluation of LWR (Line Width Roughness)] For the LS pattern formed in the "Resist Pattern Formation" section above, the 3σ value representing the LWR dimension was calculated. This value is referred to as "LWR (nm)" and is shown in Tables 7-10 of the lithography evaluation results. "3σ" refers to the value (unit: nm) triple the standard deviation (σ) obtained by measuring the line position 400 in the longitudinal direction of the line using a scanning electron microscope (accelerating voltage 800 V, trade name: S-9380, manufactured by Hitachi High Technologies Co., Ltd.). The smaller the 3σ value is, the smaller the roughness of the line sidewall is, and the more uniform the width of the LS pattern is.

[0428]

[0429]

[0430]

[0431]

[0432] As shown in Tables 7 to 10, it can be confirmed that the resist composition of the embodiment is more capable of achieving both sensitivity and LWR reduction during resist pattern formation than the resist composition of the comparative example.

[0433] ･Comparison between Example 1 and Comparative Examples 1 and 2 The resist composition of Example 1 containing compound (B0-1) was compared with the resist composition of Comparative Example 1 containing compound (B-1) having three iodine atoms but only one aromatic ring. The resist composition of Example 1 had a significantly lower LWR value and good roughness reduction properties. Furthermore, the resist composition of Example 1 containing compound (B0-1) was compared with the resist composition of Comparative Example 2 containing compound (B-2) having three iodine atoms and two aromatic rings, one of which has no iodine atoms. The resist composition of Example 1 had a significantly lower LWR value and better roughness reduction properties. This is presumably because compound (B0-1) has two aromatic rings containing iodine atoms, and therefore has good acid diffusion suppression and excellent roughness reduction properties.

[0434] ･Comparison between Example 17 and Comparative Example 3 The resist composition of Example 17 containing compound (B0-17) was compared with the resist composition of Comparative Example 3 containing compound (B-3) having two aromatic rings with iodine atoms but only one iodine atom on the aromatic ring closer to the sulfonic acid anion. The resist composition of Example 17 had significantly lower Eop and LWR values, high sensitivity, and good roughness reduction. This is presumably because compound (B0-17) has two iodine atoms on the aromatic ring closer to the sulfonic acid anion, so the acid strength generated by exposure is more moderate.

[0435] The above describes preferred embodiments of the present invention, but the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications are possible without departing from the spirit of the present invention. The present invention is not limited to the foregoing description, but only to the scope of the claims.

Claims

1. A resist composition that generates acid upon exposure and whose solubility in a developing solution changes due to the acid, comprising a substrate component (A) whose solubility in the developing solution changes due to the acid, and an acid-generating agent component (B) that generates the aforementioned acid upon exposure, wherein the acid-generating agent component (B) comprises a compound (BO) represented by the following general formula (b0). [In the formula, Ar0 is an aryl or heteroaryl group, Rm1 and Rm2 are each independently a substituent other than an iodine atom, L01 is a divalent linkage or a single bond, L02 is a divalent linkage, Vb0 is a single bond, an alkyl group or a fluorinated alkyl group, R0 is a hydrogen atom, a fluorinated alkyl group with 1 to 5 carbon atoms or a fluorine atom, nb1 is an integer of 2 to 4, nb2 is an integer of 1 to 3, nb3 is an integer of 0 to 2, nb4 is an integer greater than 0, nb5 is an integer greater than 1, Mm+ represents an m-valent organic cation, where m is an integer greater than 1].

2. The inhibitor composition as claimed in claim 1, wherein, The sum of the aforementioned nb1 and nb5 is an integer between 4 and 9.

3. The inhibitor composition as claimed in claim 1 or 2, wherein, The aforementioned Ar0 is an exenylphenyl group.

4. The inhibitor composition as claimed in claim 1 or 2, wherein, The content of the aforementioned acid generating agent component (B) is 15 to 50 parts by mass relative to 100 parts by mass of the aforementioned base material component (A).

5. A method for forming a resist pattern, comprising: a step of forming a resist film by using a resist composition as claimed in claim 1 or 2 on a support; a step of exposing the aforementioned resist film; and a step of developing the exposed resist film to form a resist pattern.

6. The method for forming the resist pattern as described in claim 5, wherein, In the step of exposing the aforementioned resist film, the resist film is exposed to EUV (extreme ultraviolet light) or EB (electron beam).

7. A compound represented by the following general formula (b0), [where Ar0 is an aryl or heteroaryl, Rm1 and Rm2 are each independently a substituent other than an iodine atom, L01 is a divalent linkage or a single bond, L02 is a divalent linkage, Vb0 is a single bond, an alkyl group or a fluorinated alkyl group, R0 is a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom, nb1 is an integer of 2 to 4, nb2 is an integer of 1 to 3, nb3 is an integer of 0 to 2, nb4 is an integer greater than 0, nb5 is an integer greater than 1, Mm+ represents an m-valent organic cation, where m is an integer greater than 1].

8. An acid generating agent comprising the compound as claimed in claim 7.