Actinic ray-sensitive or radiation-sensitive resin composition, resist film, pattern formation method, and electronic device manufacturing method

Abstract

Provided are: an actinic ray-sensitive or radiation-sensitive resin composition containing solvent and a resin (X) having a repeating unit (u1), wherein the repeating unit (u1) includes a cation having a specific structure and an anion bonded to the molecular chain of the resin (X), and the content of the repeating unit (u1) is 40 mass% or more relative to the total amount of resin contained in the actinic ray-sensitive or radiation-sensitive resin composition; a resist film using the actinic ray-sensitive or radiation-sensitive resin composition; a pattern formation method; and an electronic device manufacturing method.

Description

Actinic ray- or radiation-sensitive resin composition, resist film, pattern forming method, and method for manufacturing electronic device

[0001] The present invention relates to an actinic ray- or radiation-sensitive resin composition, a resist film, a pattern forming method, and a method for manufacturing an electronic device. More specifically, the present invention relates to an actinic ray- or radiation-sensitive resin composition that can be suitably used in ultra-microlithography processes applicable to processes for manufacturing VLSI (Large Scale Integration) and high-capacity microchips, processes for creating molds for nanoimprinting, and processes for manufacturing high-density information recording media, as well as other photofabrication processes, and to a resist film, a pattern forming method, and a method for manufacturing an electronic device using the actinic ray- or radiation-sensitive resin composition.

[0002] Conventionally, in the manufacturing process of semiconductor devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration), microfabrication is performed by lithography using resist compositions. In recent years, with the increasing integration density of integrated circuits, there has been a demand for ultrafine pattern formation in the submicron or quarter-micron range. Accordingly, there has been a trend toward shorter exposure wavelengths, from g-line to i-line and then to KrF excimer laser light, and currently, exposure machines using ArF excimer lasers with a wavelength of 193 nm as a light source have been developed. Furthermore, as a technique for further improving resolution, the so-called immersion method, in which a high refractive index liquid (hereinafter also referred to as "immersion liquid") is filled between the projection lens and the sample, has been developed.

[0003] Currently, in addition to excimer laser light, lithography using electron beams (EB), X-rays, extreme ultraviolet rays (EUV), etc. is also being developed. Accordingly, resist compositions that are effectively sensitive to various types of actinic rays or radiation have been developed.

[0004] Patent Document 1 describes a composition containing an onium salt having a specific structure. Patent Document 2 describes a photoresist composition containing a first polymer having a specific structure containing 50 to 100 mol % of a photoacid-generating repeating unit based on 100 mol % of all repeating units, and a second polymer that exhibits a change in solubility in an alkaline developer under the action of an acid.

[0005] International Publication No. 2018 / 074382 Japanese Patent Application Laid-Open No. 2016-81053

[0006] Recently, the performance required of resist compositions has become increasingly higher. In particular, further improvements are required in sensitivity, local dimensional uniformity (LCDU), and resolution when forming fine patterns (e.g., contact hole patterns with diameters of 20 nm or less, and 1:1 line-and-space patterns with line widths of 20 nm or less).

[0007] An object of the present invention is to provide an actinic ray-sensitive or radiation-sensitive resin composition that is excellent in sensitivity, LCDU, and resolution. Another object of the present invention is to provide a resist film, a pattern formation method, and a method for manufacturing an electronic device that use the actinic ray-sensitive or radiation-sensitive resin composition.

[0008] The present inventors have found that the above problems can be solved by the following configuration.

[0009] [1] An actinic ray-sensitive or radiation-sensitive resin composition comprising a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) comprises at least one cation selected from the group consisting of cations represented by the following formula (CT-1) and cations represented by the following formula (CT-2), and an anion bonded to a molecular chain of the resin (X), and the content of the repeating unit (u1) is 40 mass% or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

[0010]

[0011] In formula (CT-1) and formula (CT-2), R ３and R ４ R each independently represents an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom. ３ If there are multiple R ３ R may be bonded to each other directly via a single bond or via a linking group to form a ring. ４ If there are multiple R ４ R may be bonded to each other directly via a single bond or via a linking group to form a ring. ５ and R ６ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ５ and R ６ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. ５ and R ６ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. ７ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ８ and R ９ each independently represents a hydrogen atom, an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom, or R ８ and R ９ are bonded to each other to form a single bond or a divalent linking group. １０ and R １１ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １０ and R １１ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １０ and R １１ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring.１ , Y ２ , Y ３ and Y ４ Each independently represents an oxygen atom or a sulfur atom. １ represents an alkylene group, a cycloalkylene group, an alkenylene group, a cycloalkenylene group, an arylene group, a heteroarylene group, or a linking group formed by bonding at least two groups selected from the group consisting of alkylene groups, cycloalkylene groups, alkenylene groups, cycloalkenylene groups, arylene groups, and heteroarylene groups via at least one group selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group, or a single bond. ２ and L ３ each independently represents a single bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, a carbonyl group, a sulfinyl group, or a sulfonyl group. a and b each independently represent an integer of 1 to 3. When a represents 1, c represents an integer of 0 to 3. When a represents 2, c represents an integer of 0 to 5. When a represents 3, c represents an integer of 0 to 7. When b represents 1, d represents an integer of 0 to 4. However, d + f is an integer of 0 to 4. When b represents 2, d represents an integer of 0 to 6. However, d + f is an integer of 0 to 6. When b represents 3, d represents an integer of 0 to 8. However, d + f is an integer of 0 to 8. e represents 0 or 1. f represents an integer of 0 to 4. However, e + f is an integer of 1 to 4. In formula (CT-1), R １ and R ２ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １ and R ２ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １ , R ２ and L １ At least two of the aromatic rings to which R are bonded may be bonded directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. １２represents an aryl group or a heteroaryl group. １２ and L １may be bonded to the aromatic ring directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. [2] An actinic ray-sensitive or radiation-sensitive resin composition containing a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change under the action of an acid, and the structure after the structural change has a larger peak area in an absorption spectrum for light with a wavelength of 300 nm to 450 nm than the peak area in an absorption spectrum for light with a wavelength of 300 nm to 450 nm of the structure before the structural change, and the content of the repeating unit (u1) is 40 mass% or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition. [3] An actinic ray-sensitive or radiation-sensitive resin composition containing a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change under the action of an acid to generate a ketone group, and the content of the repeating unit (u1) is 40 mass% or more relative to the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition. [4] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [3], wherein the repeating unit (u1) is a repeating unit that generates an acid upon irradiation with actinic rays or radiation. [5] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [4], which satisfies at least one of the following conditions (i) and (ii): Condition (i): The actinic ray-sensitive or radiation-sensitive resin composition contains an acid diffusion controller that is a compound different from the resin (X). Condition (ii): The resin (X) has a repeating unit that has acid diffusion control ability.[6] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [5], wherein the content of the repeating unit (u1) is 60% by mass or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition. [7] The actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [6], wherein the content of the repeating unit (u1) is 80% by mass or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition. [8] A resist film formed using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [7]. [9] A pattern formation method comprising the steps of: forming a resist film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of [1] to [7]; irradiating the resist film with a first actinic ray or radiation; irradiating the resist film after the irradiation with the first actinic ray or radiation with a second actinic ray or radiation; and developing the resist film after the irradiation with the second actinic ray or radiation using a developer.

[10] The pattern formation method according to [9], wherein the wavelength of the first actinic ray or radiation is shorter than the wavelength of the second actinic ray or radiation.

[11] The pattern formation method according to [9] or

[10] , wherein the first actinic ray or radiation is an electron beam or extreme ultraviolet light.

[12] The pattern formation method according to any one of [9] to

[11] , wherein a first active species is generated in the resist film by irradiation with the first actinic ray or radiation, the structure of the cation is changed by the first active species, and a second active species is generated from the cation whose structure has been changed by irradiation with the second actinic ray or radiation.

[13] The pattern formation method according to any one of [9] to

[12] , wherein the developer is an alkaline aqueous solution.

[14] The pattern formation method according to any one of [9] to

[12] , wherein the developer is an organic solvent.

[15] A method for manufacturing an electronic device, comprising the pattern formation method according to any one of [9] to

[14] .

[0012] The present invention provides an actinic ray-sensitive or radiation-sensitive resin composition having excellent sensitivity, LCDU, and resolution. The present invention also provides a resist film, a pattern forming method, and a method for manufacturing an electronic device, which use the actinic ray-sensitive or radiation-sensitive resin composition.

[0013] The present invention will be described in detail below. The following description of the components will be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0014] In this specification, "actinic rays" or "radiation" refers to, for example, the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet rays (EUV), X-rays, soft X-rays, and electron beams (EB). In this specification, "light" refers to actinic rays or radiation. Unless otherwise specified, in this specification, "exposure" includes not only exposure using the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet rays, X-rays, and EUV, but also drawing using particle beams such as electron beams and ion beams. In this specification, the word "to" is used to mean that the numerical values ​​before and after it are included as the lower and upper limits.

[0015] In this specification, (meth)acrylate refers to at least one of acrylate and methacrylate, and (meth)acrylic acid refers to at least one of acrylic acid and methacrylic acid.

[0016] In this specification, the weight average molecular weight (Mw), number average molecular weight (Mn), and dispersity (also referred to as molecular weight distribution) (also referred to as "Mw / Mn" or "PDI") of a resin are defined as polystyrene-equivalent values ​​measured by GPC (Gel Permeation Chromatography) using a GPC apparatus (HLC-8120GPC manufactured by Tosoh Corporation) (solvent: tetrahydrofuran, flow rate (sample injection amount): 10 μL, column: TSK gel Multipore HXL-M manufactured by Tosoh Corporation, column temperature: 40° C., flow rate: 1.0 mL / min, detector: differential refractive index detector).

[0017] In the description of groups (atomic groups) in this specification, unless contrary to the spirit of the present invention, notations that do not specify whether they are substituted or unsubstituted include groups that contain a substituent as well as groups that do not have a substituent. For example, the term "alkyl group" includes not only alkyl groups that do not have a substituent (unsubstituted alkyl groups) but also alkyl groups that have a substituent (substituted alkyl groups). Furthermore, the term "organic group" in this specification refers to a group containing at least one carbon atom. Unless otherwise specified, a monovalent substituent is preferred as the substituent. Examples of the substituent include monovalent non-metallic atomic groups excluding hydrogen atoms, which can be selected, for example, from the following substituents T:

[0018] (Substituent T) Examples of the substituent T include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom; alkoxy groups such as a methoxy group, an ethoxy group, and a tert-butoxy group; a cycloalkyloxy group; an aryloxy group such as a phenoxy group and a p-tolyloxy group; an alkoxycarbonyl group such as a methoxycarbonyl group and a butoxycarbonyl group; a cycloalkyloxycarbonyl group; an aryloxycarbonyl group such as a phenoxycarbonyl group; an acyloxy group such as an acetoxy group, a propionyloxy group, and a benzoyloxy group; an acetyl group, a benzoyl group, an isobutyryl group, Examples of the substituent T include acyl groups such as acryloyl, methacryloyl, and methoxalyl; sulfanyl groups; alkylsulfanyl groups such as methylsulfanyl and tert-butylsulfanyl; arylsulfanyl groups such as phenylsulfanyl and p-tolylsulfanyl; alkyl groups; alkenyl groups; cycloalkyl groups; aryl groups; aromatic heterocyclic groups; hydroxy groups; carboxyl groups; formyl groups; sulfo groups; cyano groups; alkylaminocarbonyl groups; arylaminocarbonyl groups; sulfonamide groups; silyl groups; amino groups; carbamoyl groups; and the like. In addition, when these substituents can further have one or more substituents, examples of the substituent T also include groups having one or more substituents selected from the above-mentioned substituents as the further substituents (e.g., monoalkylamino groups, dialkylamino groups, arylamino groups, trifluoromethyl groups, etc.). However, when R in formula (N1) １ｂ and R ２ｂ In the case where it is described as not having a fluorine atom, such as "a substituent not having a fluorine atom," the above substituent T does not include a fluorine atom.

[0019] In this specification, the bonding direction of a divalent group is not limited unless otherwise specified. For example, when Y is -COO- in a compound represented by the formula "X-Y-Z", Y may be -CO-O- or -O-CO-. The compound may be either "X-CO-O-Z" or "X-O-CO-Z".

[0020] In this specification, the acid dissociation constant (pKa) refers to the pKa in an aqueous solution, and specifically, is a value determined by calculation using the following software package 1 based on a database of Hammett's substituent constants and known literature values. All pKa values ​​described in this specification are values ​​determined by calculation using this software package. Software package 1: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994-2007 ACD / Labs).

[0021] The pKa can also be calculated by molecular orbital calculation. A specific method for this is to calculate the pKa of H in an aqueous solution based on the thermodynamic cycle. ＋ One method is to calculate the dissociation free energy. ＋ The dissociation free energy can be calculated by, for example, DFT (density functional theory), but various other methods have been reported in the literature, and the method is not limited to these. There are several software programs that can perform DFT, and Gaussian 16 is an example.

[0022] In this specification, pKa refers to a value calculated based on a database of Hammett's substituent constants and publicly known literature values ​​using software package 1, as described above, but if pKa cannot be calculated by this method, a value obtained by Gaussian 16 based on DFT (density functional theory) will be adopted. In this specification, pKa refers to "pKa in aqueous solution" as described above, but if pKa in aqueous solution cannot be calculated, "pKa in dimethyl sulfoxide (DMSO) solution" will be adopted.

[0023] In this specification, "solid content" refers to components that form an actinic ray-sensitive or radiation-sensitive film (or a resist film when the actinic ray-sensitive or radiation-sensitive film is a resist composition), and does not include solvents. Furthermore, any component that forms an actinic ray-sensitive or radiation-sensitive film is considered to be a solid content even if it is in a liquid state.

[0024] In this specification, the peak area of ​​the absorption spectrum for light with a wavelength of 300 nm to 450 nm refers to a value obtained by integrating the peaks in the wavelength range of 300 nm to 450 nm in the ultraviolet-visible absorption spectrum. All peak areas of the absorption spectrum for light with a wavelength of 300 nm to 450 nm described in this specification are values ​​obtained by calculation using the following method. The peak areas were obtained using Gaussian 16 as the electronic state calculation software provided by Gaussian, and by TD-DFT calculations using B3LYP / 6-31+G(d) and the IEFPCM method with acetonitrile solvent conditions, and by UV-Vis spectrum calculations using the calculation software GaussView under conditions of a half-width of 0.2 eV and an output wavelength interval of 1 nm.

[0025] <Actinic ray-sensitive or radiation-sensitive resin composition> The actinic ray-sensitive or radiation-sensitive resin composition of the present invention (also referred to as "the composition of the present invention") is an actinic ray-sensitive or radiation-sensitive resin composition comprising a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) comprises at least one cation selected from the group consisting of cations represented by the following formula (CT-1) and cations represented by the following formula (CT-2), and an anion bonded to a molecular chain of the resin (X), and the content of the repeating unit (u1) is 40 mass% or more relative to the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

[0026]

[0027] In formula (CT-1) and formula (CT-2), R ３ and R ４ R each independently represents an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom. ３ If there are multiple R ３ R may be bonded to each other directly via a single bond or via a linking group to form a ring. ４ If there are multiple R ４R may be bonded to each other directly via a single bond or via a linking group to form a ring. ５ and R ６ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ５ and R ６ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. ５ and R ６ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. ７ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ８ and R ９ each independently represents a hydrogen atom, an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom, or R ８ and R ９ are bonded to each other to form a single bond or a divalent linking group. １０ and R １１ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １０ and R １１ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １０ and R １１ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. １ , Y ２ , Y ３ and Y ４ Each independently represents an oxygen atom or a sulfur atom. １represents an alkylene group, a cycloalkylene group, an alkenylene group, a cycloalkenylene group, an arylene group, a heteroarylene group, or a linking group formed by bonding at least two groups selected from the group consisting of alkylene groups, cycloalkylene groups, alkenylene groups, cycloalkenylene groups, arylene groups, and heteroarylene groups via at least one group selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group, or a single bond. ２ and L ３ each independently represents a single bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, a carbonyl group, a sulfinyl group, or a sulfonyl group. a and b each independently represent an integer of 1 to 3. When a represents 1, c represents an integer of 0 to 3. When a represents 2, c represents an integer of 0 to 5. When a represents 3, c represents an integer of 0 to 7. When b represents 1, d represents an integer of 0 to 4. However, d + f is an integer of 0 to 4. When b represents 2, d represents an integer of 0 to 6. However, d + f is an integer of 0 to 6. When b represents 3, d represents an integer of 0 to 8. However, d + f is an integer of 0 to 8. e represents 0 or 1. f represents an integer of 0 to 4. However, e + f is an integer of 1 to 4. In formula (CT-1), R １ and R ２ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １ and R ２ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １ , R ２ and L １ At least two of the aromatic rings to which R are bonded may be bonded directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. １２ represents an aryl group or a heteroaryl group. １２ and L １may be bonded to the aromatic ring directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring.

[0028] The composition of the present invention is typically a resist composition, and may be either a positive resist composition or a negative resist composition. The composition of the present invention may be a resist composition for alkali development or a resist composition for organic solvent development. The composition of the present invention is preferably a chemically amplified resist composition. An actinic ray-sensitive or radiation-sensitive film can be formed using the composition of the present invention. The actinic ray-sensitive or radiation-sensitive film formed using the composition of the present invention is typically a resist film. First, the various components of the composition of the present invention will be described in detail below.

[0029] [Resin (X)] Resin (X) has a repeating unit (u1) containing at least one cation selected from the group consisting of cations represented by the above formula (CT-1) and cations represented by the above formula (CT-2), and an anion bonded to the molecular chain of resin (X). Resin (X) may be a linear polymer or a non-linear polymer (for example, a polymer having a branched, graft, comb, star, cyclic, or network structure), or a mixture of a linear polymer and a non-linear polymer.

[0030] The resin (X) may have a repeating unit other than the repeating unit (u1) in addition to the repeating unit (u1), or may have only the repeating unit (u1) (it may be a resin consisting only of the repeating unit (u1)).

[0031] (Repeating Unit (u1)) The repeating unit (u1) contains at least one cation selected from the group consisting of cations represented by the above formula (CT-1) and cations represented by the above formula (CT-2), and an anion bonded to the molecular chain of the resin (X). The molecular chain of the resin (X) is a group formed by covalently bonding multiple atoms, and when the resin (X) is a linear polymer, examples of the molecular chain include the main chain and side chain. Furthermore, when the resin (X) is a non-linear polymer (for example, a polymer having a branched, graft, comb, star, cyclic, or network structure), examples of the molecular chain include a molecular chain that forms at least a part of the structure of the non-linear polymer. The anion contained in the repeating unit (u1) is preferably covalently bonded to the molecular chain of the resin (X). The repeating unit (u1) may have only one anion bonded to the molecular chain of the resin (X), or may have two or more anions bonded to the molecular chain of the resin (X). When two or more anions are present, the anions may be the same or different.

[0032] The repeating unit (u1) contains at least one cation (also referred to as "cation (CT)") selected from the group consisting of cations represented by the above formula (CT-1) and cations represented by the above formula (CT-2). It is preferable that the cation (CT) is not covalently bonded to the molecular chain of the resin (X).

[0033] R in formula (CT-1) and formula (CT-2) ３ and R ４ R each independently represents an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom. ３ and R ４The organic group represented by is not particularly limited, but is preferably an organic group having 1 to 20 carbon atoms, and more preferably an organic group having 1 to 12 carbon atoms. Examples of the organic group include an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkoxy group, a cycloalkyloxy group, an alkylcarbonyl group, a cycloalkylcarbonyl group, an arylcarbonyl group, a heteroarylcarbonyl group, an alkoxycarbonyl group, a cycloalkyloxycarbonyl group, an aryloxycarbonyl group, a heteroaryloxycarbonyl group, an arylsulfanylcarbonyl group, a heteroarylsulfanylcarbonyl group, an arylsulfanyl group, a heteroarylsulfanyl group, an alkylsulfanyl group, an aryl group, a heteroaryl group, an aryloxy group, Examples of such groups include heteroaryloxy groups, alkylsulfinyl groups, arylsulfinyl groups, heteroarylsulfinyl groups, alkylsulfonyl groups, arylsulfonyl groups, arylsulfonyl groups, heteroarylsulfonyl groups, (meth)acryloyloxy groups, hydroxy(poly)alkyleneoxy groups, alkylamino groups, dialkylamino groups, arylamino groups, diarylamino groups, N-alkyl-N-arylamino groups, cyano groups, alkylthio groups, cycloalkylthio groups, arylthio groups, dialkylphosphino groups, diarylphosphino groups, trialkylsilyl groups, and triarylsilyl groups.

[0034] R ３ and R ４ The alkyl group represented by may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 6. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a t-butyl group, an n-pentyl group, and an n-hexyl group.

[0035] R ３ and R ４ Among the groups described above as the organic group represented by R, the explanation, specific examples and preferred ranges of the alkyl group in the group containing an alkyl group (for example, an alkoxy group, an alkylcarbonyl group, etc.) are as described above for R ３ and R４ The same applies to the alkyl group represented by

[0036] R ３ and R ４ The cycloalkyl group represented by may be either monocyclic or polycyclic. The number of carbon atoms in the cycloalkyl group is not particularly limited, but is preferably 4 to 20, and more preferably 5 to 15. Examples of the cycloalkyl group include a cyclopentyl group, a cyclohexyl group, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. One of the methylene groups constituting the cycloalkane ring of the cycloalkyl group may be replaced with a heteroatom such as an oxygen atom or a sulfur atom, a group having a heteroatom such as a carbonyl group, a sulfonyl group, or an ester bond, or a vinylidene group.

[0037] R ３ and R ４ Among the groups described above as the organic group represented by R, the explanation, specific examples and preferred ranges of the cycloalkyl group in the group containing a cycloalkyl group (for example, a cycloalkyloxy group, a cycloalkylcarbonyl group, etc.) are as described above for R ３ and R ４ The same applies to the cycloalkyl group represented by the formula (I).

[0038] R ３ and R ４ The aryl group represented by may be either monocyclic or polycyclic. The number of carbon atoms in the aryl group is not particularly limited, but is preferably 6 to 20, and more preferably 6 to 14. The aryl group is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

[0039] R ３ and R ４ Among the groups described above as the organic group represented by R, the explanation, specific examples and preferred ranges of the aryl group in the group containing an aryl group (for example, an aryloxy group, an arylcarbonyl group, etc.) are as described above in R ３ and R ４ The same applies to the aryl group represented by the formula (I).

[0040] R ３ and R４ The heteroaryl group represented by may be either monocyclic or polycyclic. The heteroaryl group preferably contains at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom as a ring member. The number of carbon atoms in the heteroaryl group is not particularly limited, but is preferably 2 to 18, more preferably 3 to 12, and even more preferably 4 to 12. The number of ring atoms in the heteroaryl group is not particularly limited, but is preferably 5 to 20, and more preferably 6 to 15. Examples of the heteroaryl group include groups obtained by removing one hydrogen atom from a five-membered aromatic heterocyclic compound such as pyrrole, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, triazole, thiophene, or furan, or a six-membered aromatic heterocyclic compound such as pyridine, pyrazine, pyrimidine, pyridazine, triazine, thiazine, or oxazine. Furthermore, the heteroaryl group may be a group obtained by removing one hydrogen atom from a compound (e.g., indole, quinoline, isoquinoline, etc.) in which the five-membered aromatic heterocyclic compound or the six-membered aromatic heterocyclic compound is fused with at least one selected from the group consisting of the five-membered aromatic heterocyclic compound, the six-membered aromatic heterocyclic compound, aromatic hydrocarbons (e.g., benzene, naphthalene, etc.), cycloalkanes (e.g., cyclopentane, cyclohexane, etc.), and non-aromatic heterocyclic compounds (e.g., five-membered non-aromatic heterocyclic compounds such as pyrrolidine, pyrroline, 2-oxazolidone, tetrahydrofuran, pyrrolidine, tetrahydrothiophene, etc., and six-membered non-aromatic heterocyclic compounds such as morpholine, piperidine, piperazine, tetrahydropyran, pyrrolidine, etc.).

[0041] R ３ and R ４ Among the groups described above as the organic group represented by R, the explanation, specific examples and preferred ranges of the heteroaryl group in the group containing a heteroaryl group (for example, a heteroaryloxy group, a heteroarylcarbonyl group, etc.) are as described above for R ３ and R ４ The same applies to the heteroaryl group represented by the formula (I).

[0042] R３ and R ４ The alkenyl group represented by may be either linear or branched. The number of carbon atoms in the alkenyl group is not particularly limited, but is preferably 2 to 20, more preferably 2 to 10, and even more preferably 2 to 6. Examples of the alkenyl group include the above-mentioned R ３ and R ４ and groups in which one or more ethylene groups constituting the alkyl group represented by the formula (I) are replaced with vinylene groups.

[0043] R ３ and R ４ The cycloalkenyl group represented by may be either monocyclic or polycyclic. The number of carbon atoms in the cycloalkenyl group is not particularly limited, but is preferably 4 to 20, and more preferably 5 to 15. Examples of the cycloalkenyl group include the above-mentioned R ３ and R ４ and groups in which one or more ethylene groups constituting the cycloalkyl group represented by the formula (I) are replaced with vinylene groups.

[0044] The organic group may further have one or more substituents. The substituents are not particularly limited. Examples of the substituents include the organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an acid-decomposable group, and a substituent formed by combining two or more of these (wherein one or more hydrogen atoms contained in the organic group, a hydroxy group, a mercapto group, an amino group, a phosphino group, a silyl group, or an acid-decomposable group are substituted with the organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, a halogen atom, or an acid-decomposable group). The term "acid-decomposable group" is the same as that described in the description of "repeating unit having an acid-decomposable group" as an example of the repeating unit (u2) described below. R ３ and R ４ The organic group represented by R preferably has an acid-decomposable group. ３ and R ４ is also preferably an acid group. ３ and R ４It is also preferable that the organic group represented by has an acid group. The acid group is preferably an acid group having a pKa of 2 or more and 16 or less, more preferably an acid group having a pKa of 4 or more and 14 or less, and even more preferably an acid group having a pKa of 6 or more and 12 or less. The pKa is the pKa of the cation (CT) determined by the method described above.

[0045] R ３ and R ４ The halogen atom represented by is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

[0046] R ３ If there are multiple R ３ R may be bonded to each other directly via a single bond or via a linking group to form a ring. ４ If there are multiple R ４ They may be bonded to each other directly via a single bond or via a linking group to form a ring. The linking group is not particularly limited. Examples of the linking group include a divalent organic group, an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a sulfinyl group (—SO—), a sulfonyl group (—SO ２ -), and linking groups formed by combining two or more of these. The divalent organic group is not particularly limited, but is preferably a divalent organic group having 1 to 20 carbon atoms, and more preferably a divalent organic group having 1 to 12 carbon atoms. Examples of the divalent organic group include a carbonyl group (-CO-), an ester group (-COO-), an alkylene group, a cycloalkylene group, an arylene group, a heteroarylene group, an alkenylene group, and groups formed by combining two or more of these. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group is preferably an alkyl group or an aryl group.

[0047] R in formula (CT-1) and formula (CT-2) ５ and R ６R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ５ and R ６ The explanation, specific examples and preferred ranges of the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group and heteroaryl group represented by R ３ and R ４ The above definitions are the same as those for the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group, and heteroaryl group represented by the formula (I).

[0048] R ５ and R ６ When contains a methylene group, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a sulfinyl group, a sulfonyl group, a carbonyl group, an ester group, and groups formed by combining two or more of these. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group is preferably an alkyl group or an aryl group.

[0049] R ５ and R ６ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. The alkylene group may be either linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 6. Examples of the alkylene group include a methylene group and an ethylene group.

[0050] R ５ and R ６ preferably represents an alkyl group.

[0051] R in formula (CT-1) and formula (CT-2) ７represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ７ The explanation, specific examples and preferred ranges of the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group and heteroaryl group represented by R ３ and R ４ The above definitions are the same as those for the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group, and heteroaryl group represented by the formula (I).

[0052] R in formula (CT-1) and formula (CT-2) ８ and R ９ each independently represents a hydrogen atom, an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom, or R ８ and R ９ are bonded to each other to form a single bond or a divalent linking group. ８ and R ９ The description, specific examples and preferred ranges of the organic group represented by R ３ and R ４ The same applies to the organic group represented by R ８ and R ９ The halogen atom represented by R is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. ８ and R ９ may be bonded to represent a single bond or a divalent linking group (R ８ and R ９ may be bonded to form a single bond or a divalent linking group). The divalent linking group is not particularly limited. Examples of the divalent linking group include at least one group selected from the group consisting of a sulfinyl group, a sulfonyl group, a carbonyl group, a methylene group, a sulfur atom, a nitrogen atom-containing group, and an oxygen atom. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group represented by R is preferably an alkyl group or an aryl group. ８ and R ９represents a hydrogen atom, or R ８ and R ９ are preferably linked to form a sulfonyl group.

[0053] R in formula (CT-1) and formula (CT-2) １０ and R １１ The description, specific examples and preferred ranges of ５ and R ６ is the same as for

[0054] Y in formula (CT-1) and formula (CT-2) １ , Y ２ , Y ３ and Y ４ each independently represents an oxygen atom or a sulfur atom, and preferably represents an oxygen atom.

[0055] L in formula (CT-1) and formula (CT-2) １ represents an alkylene group, a cycloalkylene group, an alkenylene group, a cycloalkenylene group, an arylene group, a heteroarylene group, or a linking group formed by bonding at least two groups selected from the group consisting of alkylene groups, cycloalkylene groups, alkenylene groups, cycloalkenylene groups, arylene groups, and heteroarylene groups via at least one group selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group, or represents a single bond.

[0056] L １ The alkylene group represented by may be either linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 6. Examples of the alkylene group include a methylene group and an ethylene group.

[0057] L １The cycloalkylene group represented by may be either monocyclic or polycyclic. The number of carbon atoms in the cycloalkylene group is not particularly limited, but is preferably 4 to 20, and more preferably 5 to 15. Examples of the cycloalkylene group include a cyclopentylene group and a cyclohexylene group. One of the methylene groups constituting the cycloalkane ring of the cycloalkylene group may be replaced with a heteroatom such as an oxygen atom or a sulfur atom, a group having a heteroatom such as a carbonyl group, a sulfonyl group, or an ester bond, or a vinylidene group.

[0058] L １ The arylene group represented by may be either monocyclic or polycyclic. The number of carbon atoms in the arylene group is not particularly limited, but is preferably 6 to 20, and more preferably 6 to 14. The arylene group is preferably a phenylene group or a naphthylene group, and more preferably a phenylene group.

[0059] L １The heteroarylene group represented by may be either monocyclic or polycyclic. The heteroarylene group preferably contains at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom as a ring member. The number of carbon atoms in the heteroarylene group is not particularly limited, but is preferably, for example, 2 to 18, more preferably 3 to 12, and even more preferably 4 to 12. The number of ring atoms in the heteroarylene group is not particularly limited, but is preferably, for example, 5 to 20, and more preferably 6 to 15. Examples of the heteroarylene group include groups obtained by removing two hydrogen atoms from five-membered aromatic heterocyclic compounds such as pyrrole, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, triazole, thiophene, and furan, or six-membered aromatic heterocyclic compounds such as pyridine, pyrazine, pyrimidine, pyridazine, triazine, thiazine, and oxazine. Furthermore, the heteroarylene group may be a group obtained by removing two hydrogen atoms from a compound (e.g., indole, quinoline, isoquinoline, etc.) fused with at least one selected from the group consisting of the five-membered aromatic heterocyclic compound or the six-membered aromatic heterocyclic compound, the five-membered aromatic heterocyclic compound, the six-membered aromatic heterocyclic compound, aromatic hydrocarbons (e.g., benzene, naphthalene, etc.), cycloalkanes (e.g., cyclopentane, cyclohexane, etc.), and non-aromatic heterocyclic compounds (e.g., five-membered non-aromatic heterocyclic compounds such as pyrrolidine, pyrroline, 2-oxazolidone, tetrahydrofuran, pyrrolidine, tetrahydrothiophene, and six-membered non-aromatic heterocyclic compounds such as morpholine, piperidine, piperazine, tetrahydropyran, pyrrolidine, etc.).

[0060] L １ The alkenylene group represented by may be either linear or branched. The number of carbon atoms in the alkenylene group is not particularly limited, but is preferably 2 to 20, more preferably 2 to 10, and even more preferably 2 to 6. Examples of the alkenylene group include the above-mentioned L １ and groups in which one or more ethylene groups constituting the alkylene group represented by the formula (I) are replaced with vinylene groups.

[0061] L１ The cycloalkenylene group represented by may be either a monocyclic or polycyclic ring. The number of carbon atoms in the cycloalkenylene group is not particularly limited, but is preferably 4 to 20, and more preferably 5 to 15. Examples of the cycloalkenylene group include the above-mentioned L １ and groups in which one or more ethylene groups constituting the cycloalkylene group represented by the formula (I) are replaced with vinylene groups.

[0062] L １ may represent a linking group in which at least two groups selected from the group consisting of alkylene groups, cycloalkylene groups, alkenylene groups, cycloalkenylene groups, arylene groups, and heteroarylene groups are bonded via at least one selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group. The explanations, specific examples, and preferred ranges of the alkylene group, cycloalkylene group, alkenylene group, cycloalkenylene group, arylene group, and heteroarylene group in "at least two groups selected from the group consisting of alkylene groups, cycloalkylene groups, alkenylene groups, cycloalkenylene groups, arylene groups, and heteroarylene groups" are the same as those in the above-mentioned L, １ The above nitrogen atom-containing group is the same as the alkylene group, cycloalkylene group, alkenylene group, cycloalkenylene group, arylene group, and heteroarylene group represented by the above. An example of the nitrogen atom-containing group is -NR-, where R represents a hydrogen atom or an organic group. The organic group represented by R is the same as the above-mentioned R ３ and R ４ The linking group may be a linking group formed by bonding at least two groups of the same type via at least one selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group.

[0063] L in formula (CT-1) and formula (CT-2) ２ and L ３ each independently represents a single bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, a carbonyl group, a sulfinyl group, or a sulfonyl group.

[0064] In formula (CT-1) and formula (CT-2), a represents an integer of 1 to 3. When a represents 1, L １ is bonded to a benzene ring, and c represents an integer of 0 to 3. When a represents 2, L １ is bonded to a naphthalene ring, and c represents an integer of 0 to 5. When a represents 3, L １ The aromatic ring to which is bonded is an anthracene ring, and c represents an integer of 0 to 7.

[0065] In formula (CT-1) and formula (CT-2), b represents an integer of 1 to 3. When b represents 1, R ９ is bonded to a benzene ring, and d represents an integer of 0 to 4. However, d+f is an integer of 0 to 4. When b represents 2, R ９ is bonded to a naphthalene ring, and d represents an integer of 0 to 6. However, d+f is an integer of 0 to 6. When b represents 3, R ９ is bonded to an anthracene ring, and d represents an integer of 0 to 8, provided that d+f is an integer of 0 to 8.

[0066] In formula (CT-1) and formula (CT-2), e represents 0 or 1. When e represents 0, L ２ and L ３ are bonded by a single bond. In formula (CT-1) and formula (CT-2), f represents an integer of 0 to 4, and may represent an integer of 0 to 2, or may represent 0 or 1. However, e+f is an integer of 1 to 4, and e+f may also be 1 or 2.

[0067] R in formula (CT-1) １ and R ２ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １ and R ２ The explanation, specific examples and preferred ranges of the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group and heteroaryl group represented by R ３ and R ４The above definitions are the same as those for the alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group, and heteroaryl group represented by the formula (I).

[0068] R １ and R ２ When contains a methylene group, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. Examples of the divalent heteroatom-containing group include an oxygen atom, a sulfur atom, a sulfinyl group, a sulfonyl group, a carbonyl group, an ester group, a nitrogen atom-containing group, and groups formed by combining two or more of these. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group is preferably an alkyl group or an aryl group.

[0069] R １ , R ２ and L １ At least two of the aromatic rings to which R is bonded may be bonded directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group is preferably an alkyl group or an aryl group.

[0070] R １ and R ２ preferably represents an aryl group. １ and R ２ represents an aryl group, and R １ and R ２ Either one of the following is L １ It is also preferred that the aromatic ring is directly bonded to the aromatic ring to which the aromatic ring is bonded via a single bond to form a ring.

[0071] R in formula (CT-2) １２ represents an aryl group or a heteroaryl group. １２The explanation, specific examples and preferred ranges of the aryl group and heteroaryl group represented by R ３ and R ４ The same applies to the aryl and heteroaryl groups represented by R １２ and L １ may be bonded to the aromatic ring directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. Examples of the nitrogen atom-containing group include -NR-, where R represents a hydrogen atom or an organic group. Examples of the organic group represented by R include the above-mentioned R ３ and R ４ The organic group is preferably an alkyl group or an aryl group.

[0072] The cation (CT) is preferably a cation represented by formula (CT-1), more preferably a cation represented by the following formula (CT-1-1) or formula (CT-1-2), and even more preferably a cation represented by formula (CT-1-2).

[0073]

[0074] In formula (CT-1-1) and formula (CT-1-2), R ４ represents an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom. ４ If there are multiple R ４ R may be bonded to each other directly via a single bond or via a linking group to form a ring. ５ and R ６ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ５ and R ６ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. ５ and R ６ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring.８ and R ９ each independently represents a hydrogen atom, an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom, or R ８ and R ９ are bonded to each other to represent a single bond or a divalent linking group. ２ and L ３ each independently represents a single bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, a carbonyl group, a sulfinyl group, or a sulfonyl group. d represents an integer of 0 to 4. ｍ１ , R ｍ２ , R ｍ３ and R ｍ４ each independently represents a substituent. t1 and t2 each independently represents an integer of 0 to 5. t3 represents an integer of 0 to 4. t4 represents an integer of 0 to 5.

[0075] R in formula (CT-1-1) and formula (CT-1-2) ４ , R ５ , R ６ , R ８ , R ９ , L ２ The explanation, specific examples and preferred ranges of L and d are respectively given in the above formula (CT-1) R ４ , R ５ , R ６ , R ８ , R ９ , L ２ , L and d.

[0076] R ｍ１ , R ｍ２ , R ｍ３ and R ｍ４ Each independently represents a substituent. The substituent is not particularly limited. Examples of the substituent include R ３ and R ４Examples of the substituent include an organic group represented by the formula (I), a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an acid-decomposable group, and a substituent formed by combining two or more of these (wherein one or more hydrogen atoms contained in the organic group, hydroxy group, mercapto group, amino group, phosphino group, silyl group, or acid-decomposable group are substituted with the organic group, hydroxy group, mercapto group, amino group, nitro group, phosphino group, silyl group, halogen atom, or acid-decomposable group). The term "acid-decomposable group" is the same as that described in the description of "repeating unit having an acid-decomposable group" as an example of the repeating unit (u2) described below.

[0077] t1 and t2 each independently represent an integer of 0 to 5, and may be an integer of 0 to 4, or may be an integer of 0 to 3. t3 represents an integer of 0 to 4, and may be an integer of 0 to 3, or may be an integer of 0 to 2. t4 represents an integer of 0 to 5, and may be an integer of 0 to 4, or may be an integer of 0 to 3.

[0078] Specific examples of the cation (CT) are shown below, but the present invention is not limited to these.

[0079]

[0080]

[0081] The cation (CT) preferably undergoes a structural change under the action of an acid, and preferably generates a ketone group as a result of the structural change. The ketone compound having the generated ketone group preferably has a peak area in its absorption spectrum for light with a wavelength of 300 nm to 450 nm that is larger than the peak area of ​​the absorption spectrum of the cation (CT) for light with a wavelength of 300 nm to 450 nm. The ketone compound preferably generates an acid upon irradiation with ultraviolet light. Cation-1 to Cation-12 each undergo a structural change under the action of an acid to generate a ketone compound. The ketone compounds obtained by structural change from Cation-1 to Cation-12 each have a peak area in their absorption spectrum for light with a wavelength of 300 nm to 450 nm that is larger than the peak area of ​​the absorption spectrum for light with a wavelength of 300 nm to 450 nm of Cation-1 to Cation-12, respectively, that are the structures before the change. The ketone compound generates an acid upon irradiation with ultraviolet light. For example, as shown below, Cation-1 undergoes a structural change under the action of an acid to generate a ketone group and give the ketone compound Ketone-1. Ketone-1 has a larger peak area in its absorption spectrum for light with wavelengths of 300 nm to 450 nm than Cation-1, the structure before the change, for light with wavelengths of 300 nm to 450 nm. Furthermore, Ketone-1 generates acid when irradiated with ultraviolet light.

[0082]

[0083] The repeating unit (u1) contains an anion bonded to the molecular chain of the resin (X). The anion is not particularly limited, but preferred examples include anions represented by any of the following formulae (an1) to (an8), with the anion represented by the following formula (an1) being particularly preferred.

[0084]

[0085] In formulas (an1) to (an8), * represents the bonding position with the molecular chain of resin (X). Ａ Each of the two R in formula (an3) independently represents an organic group. Ａmay be the same or different.

[0086] R Ａ The organic group represented by is not particularly limited, but examples thereof include organic groups having 1 to 20 carbon atoms, and organic groups having 1 to 10 carbon atoms are preferred. The organic group may contain a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Preferred examples of the organic group include a cyano group, an alkyl group, a cycloalkyl group, and an aryl group. The organic group may have a substituent, and examples of the substituent include, but are not particularly limited to, a halogen atom, a hydroxy group, and a fluorine atom is preferred.

[0087] The anion represented by any one of formulas (an1) to (an8) may be bonded to an aliphatic group or an aromatic group contained in the molecular chain of resin (X). When the anion represented by any one of formulas (an1) to (an8) is bonded to an aliphatic group contained in the molecular chain of resin (X), the aliphatic group may have a substituent and preferably has a fluorine atom. When the anion represented by formulas (an1) to (an8) is bonded to an aromatic group contained in the molecular chain of resin (X), the aromatic group may have a substituent and preferably has a fluorine atom.

[0088] The repeating unit (u1) is preferably represented by the following formula (UA1).

[0089]

[0090] In formula (UA1), R ａ１ , R ａ２ and R ａ３ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. ａ１ represents a single bond or a divalent linking group. １ － represents an anion. ＋ represents a cation (CT).

[0091] R in formula (UA1) ａ１ , R ａ２ and R ａ３R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. ａ１ , R ａ２ and R ａ３ The alkyl group in R may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 5, and particularly preferably 1 to 3. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group. ａ１ , R ａ２ and R ａ３ The number of carbon atoms in the cycloalkyl group is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. ａ１ , R ａ２ and R ａ３ The cycloalkyl group in R may be a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. ａ１ , R ａ２ and R ａ３ Examples of the halogen atom in R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom or an iodine atom is preferred. ａ１ , R ａ２ and R ａ３ The alkyl group contained in the alkoxycarbonyl group may be either linear or branched. The number of carbon atoms in the alkyl group contained in the alkoxycarbonyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 5, and particularly preferably 1 to 3.

[0092] L in formula (UA1) ａ１ represents a single bond or a divalent linking group. ａ１ The divalent linking group represented by is —CO—, —O—, —S—, —SO—, —SO ２ -, -NR Ｂ -, an aliphatic group, an aromatic group, and a linking group in which a plurality of these groups are linked together. Ｂrepresents a hydrogen atom or an organic group. The aliphatic group is preferably an aliphatic group having 1 to 20 carbon atoms, such as an alkylene group, a cycloalkylene group, or an alkenylene group. The alkylene group may be linear or branched. The alkylene group preferably has 1 to 20 carbon atoms, more preferably 1 to 10, and even more preferably 1 to 5. The cycloalkylene group has no particular limitation on the number of carbon atoms, but preferably has 3 to 20, and more preferably has 5 to 15. The cycloalkylene group may be a monocyclic cycloalkylene group or a polycyclic cycloalkylene group. The alkenylene group may be linear or branched. The alkenylene group preferably has 2 to 20 carbon atoms, more preferably 2 to 10, and even more preferably 2 to 5. The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group. Examples of the aromatic hydrocarbon group include arylene groups having 6 to 18 carbon atoms, such as a phenylene group, a tolylene group, a naphthylene group, and an anthracenylene group. Phenylene or naphthylene is particularly preferred, and phenylene is most preferred. Examples of the aromatic heterocyclic group include groups containing heterocycles such as a thiophene ring, a furan ring, a pyrrole ring, a benzothiophene ring, a benzofuran ring, a benzopyrrole ring, a triazine ring, an imidazole ring, a benzimidazole ring, a triazole ring, a thiadiazole ring, and a thiazole ring. The aliphatic group and the aromatic group may have a substituent. The substituent is not particularly limited, but examples include an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a halogen atom, and a hydroxy group, with a fluorine atom being preferred.

[0093] L ａ１ Preferably, the group contains an arylene group, more preferably an arylene group having a fluorine atom.

[0094] R Ｂ The organic group represented by is not particularly limited, and examples thereof include organic groups having 1 to 20 carbon atoms. The organic group may contain a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Preferred examples of the organic group include a cyano group, an alkyl group, a cycloalkyl group, and an aryl group.

[0095] E in formula (UA1) １－ represents an anion. １ － As the anion, for example, an anion represented by any one of the above formulas (an1) to (an7) is preferred, and the anion represented by the above formula (an1) is particularly preferred.

[0096] M in formula (UA1) ＋ represents a cation (CT). The explanation, specific examples, and preferred range of the cation (CT) are the same as those described above.

[0097] The repeating unit (u1) is preferably represented by the following formula (UA2).

[0098]

[0099] In formula (UA2), R ａ１ , R ａ２ and R ａ３ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. ａ２ represents a single bond or a divalent linking group. １ represents an aromatic group. ａ４ represents a substituent other than a fluorine atom. k1 represents an integer of 1 or more. k2 represents an integer of 0 or more. E １ － represents an anion. ＋ represents a cation (CT).

[0100] R in formula (UA2) ａ１ , R ａ２ , R ａ３ , E １ － and M ＋ The explanation, specific examples and preferred ranges of R in the above formula (UA1) are as follows: ａ１ , R ａ２ , R ａ３ , E １ － and M ＋ is the same as

[0101] L in formula (UA2) ａ２ represents a single bond or a divalent linking group. ａ２ The divalent linking group represented by is —CO—, —O—, —S—, —SO—, —SO２ -, an aliphatic group, an aromatic group, and a linking group in which a plurality of these groups are linked together. ａ２ The divalent linking group represented by is —COO—, —O—, —SO ３ -, an aliphatic group, an aromatic group, or a linking group in which a plurality of these groups are linked is preferred.

[0102] L ａ２ The explanation, specific examples and preferred ranges of the aliphatic group and aromatic group represented by are respectively described in the above formula (UA1) L ａ１ The explanations, specific examples and preferred ranges of the aliphatic group and aromatic group represented by are the same as those of the aliphatic group and aromatic group represented by the formula (I).

[0103] Ar in formula (UA2) １ represents an aromatic group. １ The aromatic group represented by may be an aromatic hydrocarbon group or an aromatic heterocyclic group. Examples of the aromatic hydrocarbon group include arylene groups having 6 to 18 carbon atoms, such as a phenylene group, a tolylene group, a naphthylene group, and an anthracenylene group. A phenylene group or a naphthylene group is particularly preferred, and a phenylene group is most preferred. Examples of the aromatic heterocyclic group include groups containing a heterocycle, such as a thiophene ring, a furan ring, a pyrrole ring, a benzothiophene ring, a benzofuran ring, a benzopyrrole ring, a triazine ring, an imidazole ring, a benzimidazole ring, a triazole ring, a thiadiazole ring, and a thiazole ring.

[0104] R in formula (UA2) ａ４ represents a substituent other than a fluorine atom. ａ４ The substituent represented by is not particularly limited as long as it is not a fluorine atom, and examples thereof include an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, and a hydroxy group.

[0105] In formula (UA2), k1 represents an integer of 1 or more. １ represents the number of fluorine atoms substituted on the aromatic group represented by Ar. １ It depends on the type of aromatic group represented by Ar. １ When represents a phenylene group, k1 preferably represents an integer of 1 to 4.

[0106] In formula (UA2), k2 represents an integer of 0 or more. １ represents the number of substituents other than fluorine atoms that can be substituted on the aromatic group represented by Ar １ It depends on the type of aromatic group represented by Ar. １ When represents a phenylene group, k2 preferably represents an integer of 0 to 3.

[0107] The repeating unit (u1) is preferably represented by the following formula (UA3).

[0108]

[0109] In formula (UA3), R ａ１ , R ａ２ and R ａ３ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. ａ２ represents a single bond or a divalent linking group. ＋ represents a cation (CT).

[0110] R in formula (UA2) ａ１ , R ａ２ , R ａ３ , L ａ２ and M ＋ The explanation, specific examples and preferred ranges of R in the above formula (UA2) are as follows: ａ１ , R ａ２ , R ａ３ , L ａ２ and M ＋ is the same as

[0111] The repeating unit (u1) is preferably a repeating unit that generates an acid upon irradiation with actinic rays or radiation (also referred to as a "photoacid-generating repeating unit"). The acid generated from the repeating unit (u1) is preferably a sulfonic acid.

[0112] The pKa of the acid generated from the repeating unit (u1) is preferably 2.0 or less, more preferably 1.0 or less, and even more preferably 0.0 or less. The pKa of the acid generated from the repeating unit (u1) may be -20.0 or more. The pKa of the acid generated from the repeating unit (u1) is determined by the above-mentioned method for the corresponding monomer. For example, when the repeating unit (u1) is X-1u shown below (M ＋ represents a cation (CT), and the acid generated from the repeating unit (u1) is the following X-1a. The pKa of the following X-1m, which is a monomer corresponding to the following X-1a, is determined by the above-mentioned method, and this value is used as the pKa of the acid generated from the following X-1u.

[0113]

[0114] The content of the photoacid-generating repeating unit relative to the total amount of resin contained in the composition of the present invention is preferably 0.300 mmol / g or more and 2.000 mmol / g or less, more preferably 0.500 mmol / g or more and 2.000 mmol / g or less, and even more preferably 0.700 mmol / g or more and 2.000 mmol / g or less.

[0115] The content of the repeating unit (u1) is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, particularly preferably 80% by mass or more, and most preferably 100% by mass, based on the total amount of repeating units in the resin (X). The content of the repeating unit (u1) is 40% by mass or more, preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, and particularly preferably 100% by mass, based on the total amount of resins contained in the composition of the present invention. The content of the repeating unit (u1) is 100% by mass or less, based on the total amount of resins contained in the composition of the present invention. The repeating unit (u1) contained in the resin (X) may be of one type, or may be of two or more types. When the repeating unit (u1) contained in the resin (X) is of two or more types, the total content thereof is preferably within the above-mentioned preferred content range. The total amount of resins contained in the composition of the present invention means the sum of the masses of all resins contained in the composition of the present invention. The term "resin" refers to a compound having a weight-average molecular weight of 3000 or more. The term "resin" includes not only resin (X) but also resins other than resin (X) (having a weight-average molecular weight of 3000 or more), such as resin (A), hydrophobic resins, and surfactants, which will be described later.

[0116] Specific examples of monomers corresponding to the structure other than the cation (CT) of the repeating unit (u1) are shown below, but the present invention is not limited to these.

[0117]

[0118]

[0119] The reason why the composition of the present invention has excellent sensitivity, LCDU, and resolution is unclear, but the inventors have hypothesized the following mechanism. However, the present invention is not limited in any way by the hypothesized mechanism. Resins having a photoacid-generating repeating unit generate acid with low diffusion, and are therefore expected to have excellent resolution for fine patterns. However, because acid diffusion is extremely suppressed, sufficient amplification cannot be achieved, and sensitivity is likely to be reduced. Furthermore, in resist compositions using conventional low-molecular-weight photoacid generators, increasing the amount of photoacid generator reduces acid generation fluctuations and improves roughness performance, but adding too much photoacid generator is thought to instead cause excessive acid diffusion and deteriorate resolution. The inventors have found that sensitivity, LCDU, and resolution are improved by adjusting the amount of repeating unit (u1) containing an anion and a cation (CT) bonded to the molecular chain of the resin to 40% by mass or more of the total amount of resin contained in the composition of the present invention. The composition of the present invention contains repeating units corresponding to a photoacid generator in an amount of 40% by mass or more relative to the total amount of resin. However, since the anions are bonded to the molecular chain of the resin, excessive acid diffusion is not caused, and sufficient amplification is obtained, which is thought to be why the composition exhibits such a remarkable effect.

[0120] (Other Repeating Units) The resin (X) may have another repeating unit in addition to the repeating unit (u1). The other repeating unit is also referred to as "repeating unit (u2)." The repeating unit (u2) is a repeating unit different from the repeating unit (u1). The content of the repeating unit (u2) may be 0% by mass or more and 60% by mass or less, based on all repeating units in the resin (X). When the resin (X) has the repeating unit (u2), the content of the repeating unit (u2) may be 1% by mass or more, 5% by mass or more, or 10% by mass or more, based on all repeating units in the resin (X). Furthermore, the content of the repeating unit (u2) may be 50% by mass or less, 40% by mass or less, or 30% by mass or less, based on all repeating units in the resin (X). The resin (X) may have only one type of repeating unit (u2), or two or more types of repeating units (u2). When the resin (X) has two or more types of repeating units (u2), the total content thereof preferably falls within the above-mentioned preferred content range.

[0121] ((Repeating unit having an acid-decomposable group)) The repeating unit (u2) may be a repeating unit having an acid-decomposable group. The repeating unit having an acid-decomposable group may be a repeating unit having an acid-decomposable group containing an unsaturated bond. The acid-decomposable group refers to a group that decomposes under the action of an acid to generate a polar group. The acid-decomposable group preferably has a structure in which the polar group is protected with a group that leaves under the action of an acid (leaving group). The polar group is preferably an alkali-soluble group, such as a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group, a sulfonic acid group, a phosphate group, a sulfonamide group, a sulfonylimide group, a (alkylsulfonyl) (alkylcarbonyl) methylene group, a (alkylsulfonyl) (alkylcarbonyl) imide group, a bis(alkylcarbonyl) methylene group, a bis(alkylcarbonyl) imide group, a bis(alkylsulfonyl) methylene group, a bis(alkylsulfonyl) imide group, a tris(alkylcarbonyl) methylene group, and an acidic group such as a tris(alkylsulfonyl) methylene group, and an alcoholic hydroxyl group. Among these, the polar group is preferably a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), or a sulfonic acid group.

[0122] Examples of the group that is eliminated by the action of an acid include groups represented by formulae (Y1) to (Y4). Formula (Y1): —C(Rx １ ) (Rx ２ ) (Rx ３ ) Formula (Y2): -C(=O)OC(Rx １ ) (Rx ２ ) (Rx ３ ) Formula (Y3): -C(R ３６ ) (R ３７ ) (OR ３８ ) Formula (Y4): -C(Rn)(H)(Ar)

[0123] In formula (Y1) and formula (Y2), Rx １ ~Rx ３ Rx each independently represents an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), or an aryl group (monocyclic or polycyclic).１ ~Rx ３ When all of Rx are alkyl groups (linear or branched), １ ~Rx ３ At least two of Rx are preferably methyl groups. １ ~Rx ３ each independently preferably represents a linear or branched alkyl group, and Rx １ ~Rx ３ More preferably, Rx each independently represents a linear alkyl group. １ ~Rx ３ may be bonded to form a monocyclic or polycyclic ring. １ ~Rx ３ The alkyl group of Rx is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group. １ ~Rx ３ The cycloalkyl group may be a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １ ~Rx ３ The aryl group in Rx is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group. １ ~Rx ３ The alkenyl group of Rx is preferably a vinyl group. １ ~Rx ３ The ring formed by combining the two is preferably a cycloalkyl group. １ ~Rx ３ The cycloalkyl group formed by bonding the two is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group, and more preferably a monocyclic cycloalkyl group having 5 to 6 carbon atoms. １ ~Rx ３In the cycloalkyl group formed by bonding these two, one of the methylene groups constituting the ring may be replaced with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. In these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced with a vinylene group. The group represented by formula (Y1) or formula (Y2) can be, for example, Rx １ is a methyl group or an ethyl group, and Rx ２ and Rx ３ and Rx are preferably bonded to form the above-mentioned cycloalkyl group. When the composition of the present invention is, for example, a resist composition for EUV exposure, １ ~Rx ３ an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, and Rx １ ~Rx ３ The ring formed by bonding these two groups preferably further has a fluorine atom or an iodine atom as a substituent.

[0124] In formula (Y3), R ３６ ~R ３８ R each independently represents a hydrogen atom or a monovalent organic group. ３７ and R ３８ may be bonded to each other to form a ring. Examples of the monovalent organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group. ３６ is also preferably a hydrogen atom. The alkyl group, cycloalkyl group, aryl group, and aralkyl group may contain a heteroatom such as an oxygen atom and / or a group containing a heteroatom such as a carbonyl group. For example, in the alkyl group, cycloalkyl group, aryl group, and aralkyl group, one or more methylene groups may be replaced with a heteroatom such as an oxygen atom and / or a group containing a heteroatom such as a carbonyl group. R ３８ may bond with another substituent on the main chain of the repeating unit to form a ring. ３８The group formed by bonding together R and another substituent on the main chain of the repeating unit is preferably an alkylene group such as a methylene group. ３６ ~R ３８ and a monovalent organic group represented by R ３７ and R ３８ It is also preferable that the ring formed by bonding these groups together further has a fluorine atom or an iodine atom as a substituent.

[0125] Formula (Y3) is preferably a group represented by the following formula (Y3-1).

[0126]

[0127] Here, L １ and L ２ Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group combining these (for example, a group combining an alkyl group and an aryl group). M represents a single bond or a divalent linking group. Q represents an alkyl group that may contain a heteroatom, a cycloalkyl group that may contain a heteroatom, an aryl group that may contain a heteroatom, an amino group, an ammonium group, a mercapto group, a cyano group, an aldehyde group, or a group combining these (for example, a group combining an alkyl group and a cycloalkyl group). In the alkyl group and the cycloalkyl group, for example, one of the methylene groups may be replaced with a heteroatom such as an oxygen atom, or a group containing a heteroatom such as a carbonyl group. In addition, L １ and L ２ It is preferred that one of Q, M, and L is a hydrogen atom, and the other is an alkyl group, a cycloalkyl group, an aryl group, or a group in which an alkylene group and an aryl group are combined. １ At least two of the groups may be bonded to form a ring (preferably a 5- or 6-membered ring). ２is preferably a secondary or tertiary alkyl group, and more preferably a tertiary alkyl group. Examples of secondary alkyl groups include an isopropyl group, a cyclohexyl group, and a norbornyl group, and examples of tertiary alkyl groups include a tert-butyl group and an adamantane group. In these embodiments, the Tg (glass transition temperature) and activation energy are increased, thereby ensuring film strength and suppressing fogging.

[0128] When the composition of the present invention is, for example, a resist composition for EUV exposure, L １ and L ２ It is also preferable that the alkyl group, cycloalkyl group, aryl group, and combinations thereof represented by the formula (I) further have a fluorine atom or an iodine atom as a substituent. The alkyl group, cycloalkyl group, aryl group, and aralkyl group preferably contain a heteroatom such as an oxygen atom in addition to the fluorine atom and iodine atom. Specifically, in the alkyl group, cycloalkyl group, aryl group, and aralkyl group, for example, one of the methylene groups may be replaced with a heteroatom such as an oxygen atom, or a group containing a heteroatom such as a carbonyl group. When the composition of the present invention is, for example, a resist composition for EUV exposure, in the alkyl group which may contain a heteroatom, cycloalkyl group which may contain a heteroatom, aryl group which may contain a heteroatom, amino group, ammonium group, mercapto group, cyano group, aldehyde group, and combinations thereof represented by Q, the heteroatom is preferably selected from the group consisting of a fluorine atom, an iodine atom, and an oxygen atom.

[0129] In formula (Y4), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group, or an aryl group. Rn and Ar may be bonded to each other to form a non-aromatic ring. Ar is preferably an aryl group. When the composition of the present invention is, for example, a resist composition for EUV exposure, it is also preferable that the aromatic ring group represented by Ar and the alkyl group, cycloalkyl group, and aryl group represented by Rn have a fluorine atom or an iodine atom as a substituent.

[0130] In terms of excellent acid decomposition properties of the repeating unit, when a non-aromatic ring is directly bonded to the polar group (or a residue thereof) in the leaving group protecting the polar group, it is also preferable that the ring atom in the non-aromatic ring adjacent to the ring atom directly bonded to the polar group (or a residue thereof) does not have a halogen atom such as a fluorine atom as a substituent.

[0131] The group that is eliminated by the action of an acid may also be a 2-cyclopentenyl group having a substituent (such as an alkyl group), such as a 3-methyl-2-cyclopentenyl group, or a cyclohexyl group having a substituent (such as an alkyl group), such as a 1,1,4,4-tetramethylcyclohexyl group.

[0132] The repeating unit having an acid-decomposable group is also preferably a repeating unit represented by formula (A).

[0133]

[0134] L １ represents a divalent linking group which may have a fluorine atom or an iodine atom, R １ represents a hydrogen atom, a fluorine atom, an iodine atom, an alkyl group which may have a fluorine atom or an iodine atom, or an aryl group which may have a fluorine atom or an iodine atom; R ２ represents a leaving group which is eliminated by the action of an acid and may have a fluorine atom or an iodine atom. １ , R １ , and R ２ At least one of L has a fluorine atom or an iodine atom. １ Examples of the divalent linking group which may have a fluorine atom or an iodine atom and is represented by the formula: ２ -, hydrocarbon groups which may have a fluorine atom or an iodine atom (for example, alkylene groups, cycloalkylene groups, alkenylene groups, arylene groups, etc.), and linking groups in which a plurality of these groups are linked together. １As the alkylene group, -CO-, an arylene group, or -arylene group-alkylene group having a fluorine atom or an iodine atom- is preferred, and -CO- or -arylene group-alkylene group having a fluorine atom or an iodine atom- is more preferred. As the arylene group, a phenylene group is preferred. The alkylene group may be linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 3. The total number of fluorine atoms and iodine atoms contained in the alkylene group having a fluorine atom or an iodine atom is not particularly limited, but is preferably 2 or more, more preferably 2 to 10, and even more preferably 3 to 6.

[0135] R １ The alkyl group represented by R may be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 3. １ The total number of fluorine atoms and iodine atoms contained in the alkyl group having a fluorine atom or an iodine atom, represented by the formula (I), is not particularly limited, but is preferably 1 or more, more preferably 1 to 5, and even more preferably 1 to 3. １ The alkyl group represented by the formula (I) may contain a heteroatom other than a halogen atom, such as an oxygen atom.

[0136] R ２ Examples of the leaving group represented by the formulae (Y1) to (Y4) above and which may have a fluorine atom or an iodine atom include leaving groups represented by the formulae (Y1) to (Y4) above and which have a fluorine atom or an iodine atom.

[0137] The repeating unit having an acid-decomposable group is also preferably a repeating unit represented by formula (AI).

[0138]

[0139] In formula (AI), Xa １ represents a hydrogen atom or an alkyl group which may have a substituent. T represents a single bond or a divalent linking group. Rx １ ~Rx ３each independently represents an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), or an aryl group (monocyclic or polycyclic). １ ~Rx ３ When all of Rx are alkyl groups (linear or branched), １ ~Rx ３ Preferably, at least two of Rx are methyl groups. １ ~Rx ３ may be bonded to form a monocyclic or polycyclic ring (such as a monocyclic or polycyclic cycloalkyl group).

[0140] Xa １ Examples of the alkyl group represented by the formula (I) which may have a substituent include a methyl group or a —CH ２ -R １１ Examples of the group include a group represented by the following formula: １１ represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. １１ Examples of the monovalent organic group represented by the formula (I) include an alkyl group having 5 or less carbon atoms which may be substituted with a halogen atom, an acyl group having 5 or less carbon atoms which may be substituted with a halogen atom, and an alkoxy group having 5 or less carbon atoms which may be substituted with a halogen atom, and an alkyl group having 3 or less carbon atoms is preferred, and a methyl group is more preferred. １ is preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0141] Examples of the divalent linking group for T include an alkylene group, an aromatic ring group, a -COO-Rt- group, and a -O-Rt- group. In the formula, Rt represents an alkylene group or a cycloalkylene group. T is preferably a single bond or a -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkylene group having 1 to 5 carbon atoms, and is preferably a -CH ２ - group, -(CH ２ ) ２ - group or -(CH ２ ) ３ The - group is more preferred.

[0142] Rx １ ~Rx ３The alkyl group of Rx is preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group. １ ~Rx ３ The cycloalkyl group of Rx is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １ ~Rx ３ The aryl group in Rx is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group. １ ~Rx ３ The alkenyl group of Rx is preferably a vinyl group. １ ~Rx ３ As the cycloalkyl group formed by combining the above two, a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group is preferred. Polycyclic cycloalkyl groups such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are also preferred. Among these, a monocyclic cycloalkyl group having 5 to 6 carbon atoms is preferred. Rx １ ~Rx ３ The cycloalkyl group formed by bonding these two may have, for example, one of the methylene groups constituting the ring replaced with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene group. Furthermore, in these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced with a vinylene group. The repeating unit represented by formula (AI) can be, for example, Rx １ is a methyl group or an ethyl group, and Rx ２ and Rx ３ and are preferably bonded to form the above-mentioned cycloalkyl group.

[0143] When each of the above groups has a substituent, examples of the substituent include an alkyl group (having 1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (having 1 to 4 carbon atoms), a carboxyl group, and an alkoxycarbonyl group (having 2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0144] The repeating unit represented by formula (AI) may be an acid-decomposable (meth)acrylic acid tertiary alkyl ester repeating unit (Xa １ represents a hydrogen atom or a methyl group, and T represents a single bond).

[0145] The resin (X) may have a repeating unit having an acid-decomposable group containing an unsaturated bond as a repeating unit having an acid-decomposable group. The repeating unit having an acid-decomposable group containing an unsaturated bond is preferably a repeating unit represented by formula (B):

[0146]

[0147] In formula (B), Xb represents a hydrogen atom, a halogen atom, or an alkyl group which may have a substituent. L represents a single bond or a divalent linking group which may have a substituent. Ry １ ~Ry ３ each independently represents a linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl group, an alkenyl group, an alkynyl group, or a monocyclic or polycyclic aryl group, provided that Ry １ ~Ry ３ At least one of R represents an alkenyl group, an alkynyl group, a monocyclic or polycyclic cycloalkenyl group, or a monocyclic or polycyclic aryl group. １ ~Ry ３ may be bonded to form a monocyclic or polycyclic ring (such as a monocyclic or polycyclic cycloalkyl group or cycloalkenyl group).

[0148] The alkyl group represented by Xb, which may have a substituent, is, for example, a methyl group or —CH ２ -R １１ Examples of the group include a group represented by the following formula: １１represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group, and examples thereof include an alkyl group having 5 or less carbon atoms which may be substituted with a halogen atom, an acyl group having 5 or less carbon atoms which may be substituted with a halogen atom, and an alkoxy group having 5 or less carbon atoms which may be substituted with a halogen atom, preferably an alkyl group having 3 or less carbon atoms, and more preferably a methyl group. Xb is preferably a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0149] Examples of the divalent linking group for L include a -Rt- group, a -CO- group, a -COO-Rt- group, a -COO-Rt-CO- group, a -Rt-CO- group, and a -O-Rt- group. In the formula, Rt represents an alkylene group, a cycloalkylene group, or an aromatic ring group, and an aromatic ring group is preferable. L is preferably a -Rt- group, a -CO- group, a -COO-Rt-CO- group, or a -Rt-CO- group. Rt may have a substituent such as a halogen atom, a hydroxyl group, or an alkoxy group.

[0150] Ry １ ~Ry ３ The alkyl group of Ry is preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group. １ ~Ry ３ The cycloalkyl group of Ry is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １ ~Ry ３ The aryl group in Ry is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group. １ ~Ry ３ The alkenyl group in Ry is preferably a vinyl group. １ ~Ry ３ The alkynyl group in Ry is preferably an ethynyl group. １ ~Ry ３The cycloalkenyl group of Ry is preferably a monocyclic cycloalkyl group having a structure containing a double bond in a part thereof, such as a cyclopentyl group or a cyclohexyl group. １ ~Ry ３ The cycloalkyl group formed by combining the above two groups is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. Among these, a monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferred. １ ~Ry ３ The cycloalkyl group or cycloalkenyl group formed by bonding two of the above is, for example, a group in which one of the methylene groups constituting the ring is substituted with a heteroatom such as an oxygen atom, a carbonyl group, or —SO ２ - group and -SO ３ The repeating unit represented by formula (B) may be substituted with a group containing a hetero atom such as a - group, a vinylidene group, or a combination thereof. In addition, in these cycloalkyl groups or cycloalkenyl groups, one or more ethylene groups constituting the cycloalkane ring or cycloalkene ring may be substituted with a vinylene group. １ is a methyl group, an ethyl group, a vinyl group, an allyl group, or an aryl group, and Ry ２ and Ry ３ and are bonded to form the above-mentioned cycloalkyl group or cycloalkenyl group.

[0151] When each of the above groups has a substituent, examples of the substituent include an alkyl group (having 1 to 4 carbon atoms), a halogen atom, a hydroxyl group, an alkoxy group (having 1 to 4 carbon atoms), a carboxyl group, and an alkoxycarbonyl group (having 2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0152] The repeating unit represented by formula (B) is preferably an acid-decomposable (meth)acrylic acid tertiary ester repeating unit (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a -CO- group), an acid-decomposable hydroxystyrene tertiary alkyl ether repeating unit (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a phenyl group), or an acid-decomposable styrene carboxylic acid tertiary ester repeating unit (a repeating unit in which Xb represents a hydrogen atom or a methyl group and L represents a -Rt-CO- group (Rt is an aromatic group)). Specific examples of repeating units having an acid-decomposable group containing an unsaturated bond include the repeating units described in paragraphs

[0067] to

[0071] of WO 2022 / 024928. The above descriptions are incorporated herein by reference.

[0153] For repeating units having an acid-decomposable group, the description in paragraphs

[0029] to

[0075] of WO 2022 / 024928 can be used. The above description is incorporated herein by reference.

[0154] Specific examples of repeating units having an acid-decomposable group are shown below, but are not limited to these.

[0155]

[0156] It is preferred that any of the resins contained in the composition of the present invention have a repeating unit having an acid-decomposable group. The content of the repeating unit having an acid-decomposable group relative to the total amount of the resins contained in the composition of the present invention is preferably 0.500 mmol / g or more and 6.000 mmol / g or less, more preferably 1.000 mmol / g or more and 6.000 mmol / g or less, and even more preferably 1.500 mmol / g or more and 6.000 mmol / g or less.

[0157] ((Repeating unit having an acid group)) The repeating unit (u2) may be a repeating unit having an acid group. Examples of the acid group include a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), a sulfonic acid group, a sulfonamide group, and an isopropanol group. In the hexafluoroisopropanol group, one or more fluorine atoms (preferably one to two) may be substituted with a group other than a fluorine atom (such as an alkoxycarbonyl group). Examples of the acid group include the -C(CF ３ )(OH)—CF ２ In addition, one or more fluorine atoms are substituted with a group other than a fluorine atom to form -C(CF ３ )(OH)—CF ２ - may form a ring containing the repeating unit. The repeating unit having an acid group is preferably a repeating unit different from the repeating unit having a structure in which a polar group is protected by a group that is cleaved by the action of an acid described above, and the repeating unit having a lactone group, a sultone group, or a carbonate group described below. The repeating unit having an acid group may have a fluorine atom or an iodine atom. Specific examples of the repeating unit having an acid group include the repeating units described in paragraphs

[0088] to

[0089] and

[0103] to

[0110] of WO 2022 / 024928. The above descriptions are incorporated herein by reference.

[0158] The repeating unit having an acid group is preferably a repeating unit having a phenolic hydroxyl group. The repeating unit having a phenolic hydroxyl group is preferably a repeating unit different from the repeating unit having an acid-decomposable group described above. The repeating unit having a phenolic hydroxyl group is preferably a repeating unit represented by the following formula (Pa2):

[0159]

[0160] In formula (Pa2), R １０１ , R １０２ and R １０３ R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group.１０２ is Ar Ａ may be bonded to form a ring, in which case R １０２ represents a single bond or an alkylene group. Ａ represents a single bond or a divalent linking group. Ａ represents an aromatic ring group, and k represents an integer of 1 to 5.

[0161] R in formula (Pa2) １０１ , R １０２ and R １０３ R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. １０１ , R １０２ and R １０３ The alkyl group in R may be either linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 5, and particularly preferably 1 to 3. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group. １０１ , R １０２ and R １０３ The number of carbon atoms in the cycloalkyl group is not particularly limited, but is preferably 3 to 20, and more preferably 5 to 15. １０１ , R １０２ and R １０３ The cycloalkyl group of R is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. １０１ , R １０２ and R １０３ Examples of the halogen atom in R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom or an iodine atom is preferred. １０１ , R １０２ and R １０３ The alkyl group contained in the alkoxycarbonyl group may be either linear or branched. The number of carbon atoms in the alkyl group contained in the alkoxycarbonyl group is not particularly limited, but is preferably 1 to 5, and more preferably 1 to 3.

[0162] Ar in formula (Pa2) Ａ represents an aromatic ring group, more specifically, a (k+1)-valent aromatic ring group. When k is 1, the divalent aromatic ring group is preferably an arylene group having 6 to 18 carbon atoms, such as a phenylene group, a tolylene group, a naphthylene group, or an anthracenylene group, or a divalent aromatic ring group containing a heterocycle, such as a thiophene ring, a furan ring, a pyrrole ring, a benzothiophene ring, a benzofuran ring, a benzopyrrole ring, a triazine ring, an imidazole ring, a benzimidazole ring, a triazole ring, a thiadiazole ring, or a thiazole ring. The aromatic ring group may have a substituent. When k is an integer of 2 or more, specific examples of the (k+1)-valent aromatic ring group include groups obtained by removing any (k-1) hydrogen atoms from the above-mentioned specific examples of the divalent aromatic ring group. The (k+1)-valent aromatic ring group may further have a substituent. The substituent that the (k+1)-valent aromatic ring group may have is not particularly limited, and examples thereof include alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, hexyl, 2-ethylhexyl, octyl, and dodecyl; alkoxy groups such as methoxy, ethoxy, hydroxyethoxy, propoxy, hydroxypropoxy, and butoxy; and aryl groups such as phenyl. Ａ preferably represents an aromatic ring group having 6 to 18 carbon atoms, and more preferably represents a benzene ring group, a naphthalene ring group or a biphenylene ring group.

[0163] L in formula (Pa2) Ａ represents a single bond or a divalent linking group. Ａ The divalent linking group represented by is not particularly limited, but examples thereof include —COO—, —CONR １０４ -, an alkylene group, or a group formed by combining two or more of these groups. １０４ represents a hydrogen atom or an alkyl group. The alkylene group is not particularly limited, but is preferably an alkylene group having 1 to 8 carbon atoms, such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, or an octylene group. R １０４When represents an alkyl group, examples of the alkyl group include alkyl groups having 20 or less carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a hexyl group, a 2-ethylhexyl group, an octyl group, and a dodecyl group, and alkyl groups having 8 or less carbon atoms are preferred.

[0164] The repeating unit represented by formula (Pa2) preferably has a hydroxystyrene structure. Ａ represents a benzene ring group. k preferably represents an integer of 1 to 3, and more preferably 1 or 2.

[0165] Specific examples of repeating units having an acid group are shown below, but are not limited to these. １ and G ２ each independently represents a hydrogen atom, a methyl group, a fluorine atom, a chlorine atom, a trifluoromethyl group, a cyano group, a hydroxy group, or a hydroxymethyl group. f1 represents an integer of 1 to 3.

[0166]

[0167] It is preferred that any of the resins contained in the composition of the present invention has a repeating unit having an acid group. The acid group is preferably an acid group having a pKa of 2 or more and 16 or less, more preferably an acid group having a pKa of 4 or more and 14 or less, and even more preferably an acid group having a pKa of 6 or more and 12 or less. The pKa is the pKa determined by the above-mentioned method for the monomer corresponding to the repeating unit having an acid group. The content of the repeating unit having an acid group relative to the total amount of resins contained in the composition of the present invention is preferably 0.500 mmol / g or more and 6.000 mmol / g or less, more preferably 1.000 mmol / g or more and 6.000 mmol / g or less, and even more preferably 1.500 mmol / g or more and 6.000 mmol / g or less.

[0168] ((Repeating unit having neither an acid-decomposable group nor an acid group, and having a fluorine atom, a bromine atom, or an iodine atom)) The repeating unit (u2) may be a repeating unit having neither an acid-decomposable group nor an acid group, and having a fluorine atom, a bromine atom, or an iodine atom (hereinafter also referred to as "unit X").

[0169] The unit X is preferably a repeating unit represented by formula (C).

[0170]

[0171] L ５ represents a single bond or an ester group. ９ represents a hydrogen atom or an alkyl group which may have a fluorine atom or an iodine atom. １０ represents a hydrogen atom, an alkyl group which may have a fluorine atom or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, an aryl group which may have a fluorine atom or an iodine atom, or a group combining these. Specific examples of repeating units having a fluorine atom or an iodine atom include the repeating units described in paragraphs

[0116] to

[0117] of WO 2022 / 024928. The above descriptions are incorporated herein by reference.

[0172] ((Repeating unit having a lactone group, a sultone group, or a carbonate group)) The repeating unit (u2) may be a repeating unit having a lactone group, a sultone group, or a carbonate group (hereinafter also referred to as "unit Y"). It is also preferable that unit Y does not have a hydroxy group or an acid group such as a hexafluoropropanol group.

[0173] The lactone group or sultone group may have a lactone structure or a sultone structure. The lactone structure or sultone structure is preferably a 5- to 7-membered lactone structure or a 5- to 7-membered sultone structure. Of these, a 5- to 7-membered lactone structure to which another ring structure is fused, forming a bicyclo or spiro structure, or a 5- to 7-membered sultone structure to which another ring structure is fused, forming a bicyclo or spiro structure, is more preferred. The carbonate group is preferably a cyclic carbonate ester group. For repeating units having a cyclic carbonate ester group, see, for example, paragraphs

[0127] to

[0133] of WO 2022 / 024928. The above descriptions are incorporated herein by reference.

[0174] The repeating unit (u2) may be a repeating unit having a lactone group, a sultone group, or a carbonate group obtained by removing one or more hydrogen atoms from a ring member atom of a lactone structure represented by any of the following formulas (LC1-1) to (LC1-22), a sultone structure represented by any of the following formulas (SL1-1) to (SL1-3), or a cyclic carbonate ester structure represented by any of the following formulas (CC1-1) to (CC1-2). Furthermore, the lactone group, sultone group, or carbonate group of the repeating unit (u2) may be directly bonded to the main chain. For example, the ring member atom of the lactone group, sultone group, or carbonate group may constitute the main chain of the resin (X). The lactone group, sultone group, and carbonate group may have a substituent.

[0175] R in the following structural formula Ｌ represents a substituent. Ｌ If there are multiple R Ｌ may be the same or different. Ｌ Examples of R include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a carboxyl group, a halogen atom, a cyano group, and an acid-decomposable group. e1 represents an integer of 0 to 4. When multiple e1s are present, the multiple e1s may be the same or different. When e1 is 2 or more, the multiple R Ｌmay be the same or different, and multiple R Ｌ They may be bonded to each other to form a ring.

[0176]

[0177] Examples of repeating units having a lactone group, a sultone group, or a carbonate group include repeating units represented by the following formula (AI-2).

[0178]

[0179] In formula (AI-2), Rb ０ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. ０ The alkyl group of Rb may have a substituent. ０ Examples of the substituent that the alkyl group of Rb may have include a hydroxyl group and a halogen atom. ０ Examples of the halogen atom in Rb include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. ０ is preferably a hydrogen atom or a methyl group. Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent linking group formed by combining these. Among these, Ab is preferably a single bond or -Ab １ -CO ２ A linking group represented by - is preferred. １ is a linear or branched alkylene group, or a monocyclic or polycyclic cycloalkylene group, and is preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group, or a norbornylene group. V is a group obtained by removing one hydrogen atom from a ring member atom of a lactone structure represented by any of formulas (LC1-1) to (LC1-22), a group obtained by removing one hydrogen atom from a ring member atom of a sultone structure represented by any of formulas (SL1-1) to (SL1-3), or a group obtained by removing one hydrogen atom from a ring member atom of a cyclic carbonate ester structure represented by any of formulas (CC1-1) to (CC1-2).

[0180] ((Repeating unit represented by formula (V-1) or formula (V-2)) The repeating unit (u2) may be a repeating unit represented by the following formula (V-1) or formula (V-2). It is preferable that the repeating unit represented by the following formula (V-1) and the repeating unit represented by the following formula (V-2) are different from the above-mentioned respective repeating units.

[0181]

[0182] In formulas (V-1) and (V-2), R ６ and R ７ each independently represents a hydrogen atom, a hydroxyl group, an alkyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR or -COOR: R is an alkyl group or a fluorinated alkyl group having 1 to 6 carbon atoms), or a carboxyl group. As the alkyl group, a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms is preferred. ３ represents an integer of 0 to 6. ４ represents an integer of 0 to 4. ４ represents a methylene group, an oxygen atom, or a sulfur atom. Examples of the repeating unit represented by formula (V-1) or formula (V-2) include the repeating units described in paragraph

[0100] of WO 2018 / 193954.

[0183] ((Repeating unit having acid diffusion control ability)) The repeating unit (u2) may be a repeating unit having acid diffusion control ability. Examples of the repeating unit having acid diffusion control ability include a repeating unit represented by the following formula (S1):

[0184]

[0185] In formula (S1), R ４１ represents a hydrogen atom or an alkyl group. ４１ represents a single bond or a divalent linking group. ４２ represents a divalent linking group. ４０represents a structural moiety that decomposes upon irradiation with actinic rays or radiation to generate an acid in a side chain, provided that the pKa of the acid is greater than the pKa of the conjugate acid of the anion bonded to the molecular chain of the resin (X) contained in the repeating unit (u1).

[0186] R in formula (S1) ４１ The alkyl group represented by may be either linear or branched, is preferably an alkyl group having 1 to 5 carbon atoms, and is more preferably a methyl group.

[0187] L ４１ represents a single bond or a divalent linking group, and preferably represents a single bond or an ester bond (—COO—).

[0188] L ４２ represents an alkylene group, a cycloalkylene group, an arylene group, —O—, —CO—, —S—, —SO—, —SO ２ Preferably, the linking group is at least one selected from the group consisting of - and -NR-. R represents a hydrogen atom or an organic group. The organic group represented by R is the same as that described above for R. ３ and R ４ Examples of the organic group include the same groups as those represented by the formula (I), and an alkyl group or an aryl group is preferred. The alkylene group may be either linear or branched. The number of carbon atoms in the alkylene group is not particularly limited, but 1 to 10 is preferred. The cycloalkylene group may be a monocyclic cycloalkylene group or a polycyclic cycloalkylene group. The number of carbon atoms in the cycloalkylene group is not particularly limited, but 3 to 20 is preferred, and 5 to 15 is more preferred. The number of carbon atoms in the arylene group is not particularly limited, but 6 to 20 is preferred, and 6 to 10 is more preferred. The alkylene group, cycloalkylene group, and arylene group may have a substituent, and examples of the substituent include the substituent T described above.

[0189] R ４０ is preferably a group represented by the following formula (S1-1).

[0190]

[0191] In formula (S1-1), Q － represents an acid residue, Z ＋represents a cation. * represents L ４１ The bond position of the acid residue is a group formed by dissociating a proton from an acid. － Yes, O － , carboxylate anion group (COO － ), sulfonate anion group (SO ３ － ), or a sulfonamide group (N － -SO ２ R Ｎ１ It is expressed as: R Ｎ１ represents an organic group, and examples thereof include organic groups having 1 to 10 carbon atoms, and an alkyl group, a fluoroalkyl group, or an aryl group is preferred. － or COO － is more preferable. － GA O － If L ４２ is preferably an arylene group, more preferably a phenylene group. ＋ is preferably a sulfonium cation or an iodonium cation. ＋ may be the same as the cation (CT) described above.

[0192] The pKa of the acid generated from the repeating unit represented by formula (S1) upon irradiation with actinic rays or radiation is preferably greater than 2.0, more preferably 2.5 or greater, and even more preferably 3.0 or greater. The pKa of the acid generated from the repeating unit represented by formula (S1) upon irradiation with actinic rays or radiation may be 13 or less. The pKa of the acid generated from the repeating unit represented by formula (S1) upon irradiation with actinic rays or radiation is determined by the above-mentioned method for the corresponding monomer.

[0193] The number of types of repeating units contained in the resin (X) is preferably from 1 to 4, more preferably from 1 to 3, and even more preferably from 1 to 2. The number of types of repeating units contained in all resins contained in the composition of the present invention is preferably from 1 to 4, more preferably from 1 to 3, and even more preferably from 1 to 2.

[0194] The resin (X) can be synthesized by a conventional method (for example, by radical polymerization).

[0195] The weight average molecular weight (Mw) of resin (X), as a polystyrene equivalent value measured by GPC, is preferably 30,000 or less, more preferably 1,000 to 30,000, even more preferably 3,000 to 30,000, and particularly preferably 5,000 to 15,000. The dispersity (molecular weight distribution, PDI, Mw / Mn) of resin (X) is preferably 1 to 5, more preferably 1 to 3, even more preferably 1 to 2.5, and particularly preferably 1 to 2.

[0196] The content of resin (X) in the composition of the present invention is not particularly limited, but is preferably 40 to 100 mass% relative to the total solid content in the composition of the present invention, more preferably 50 to 100 mass%, even more preferably 60 to 100 mass%, and particularly preferably 70 to 100 mass%. Resin (X) may be used alone or in combination with two or more types. When two or more types of resin (X) are used, it is preferable that the total content thereof is within the above-mentioned preferred content range.

[0197] The composition of the present invention may contain other components in addition to the resin (X).

[0198] [Resin (A) whose polarity increases under the action of acid] The composition of the present invention may contain a resin (also referred to as "resin (A)") whose polarity increases under the action of acid, which is different from resin (X). Resin (A) is a resin that does not have the repeating unit (u1) described above. Resin (A) contains a group that decomposes under the action of acid to increase polarity (acid-decomposable group), and preferably contains a repeating unit having an acid-decomposable group.

[0199] The "repeating unit having an acid-decomposable group" that the resin (A) may have is the same as the "repeating unit having an acid-decomposable group" exemplified above for the repeating unit (u2).

[0200] The content of the repeating units having an acid-decomposable group is preferably 15 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, based on the total repeating units in the resin (A), and the upper limit thereof is preferably 90 mol% or less, more preferably 80 mol% or less, even more preferably 70 mol% or less, and particularly preferably 60 mol% or less, based on the total repeating units in the resin (A).

[0201] Resin (A) may contain at least one repeating unit selected from the group consisting of Group A below, and / or at least one repeating unit selected from the group consisting of Group B below. Group A: A group consisting of the following repeating units (20) to (25). (20) A repeating unit having an acid group; (21) A repeating unit having neither an acid-decomposable group nor an acid group, and having a fluorine atom, a bromine atom, or an iodine atom; (22) A repeating unit having a lactone group, a sultone group, or a carbonate group; (23) A repeating unit represented by formula (V-1) or formula (V-2); (24) A repeating unit for reducing main chain mobility. The repeating units represented by formulas (A) to (E), which will be described later, correspond to (24) A repeating unit for reducing main chain mobility. Group B: A group consisting of the following repeating units (30) to (32). (30) A repeating unit having at least one group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, a cyano group, and an alkali-soluble group. (31) A repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposition. (32) A repeating unit represented by formula (III) having neither a hydroxyl group nor a cyano group.

[0202] The "repeating unit having an acid group," "repeating unit having neither an acid-decomposable group nor an acid group and having a fluorine atom, a bromine atom or an iodine atom," "repeating unit having a lactone group, a sultone group or a carbonate group," and "repeating unit represented by formula (V-1) or (V-2)" that the resin (A) may have are the same as the "repeating unit having an acid group," "repeating unit having neither an acid-decomposable group nor an acid group and having a fluorine atom, a bromine atom or an iodine atom," "repeating unit having a lactone group, a sultone group or a carbonate group," and "repeating unit represented by formula (V-1) or (V-2)" listed above for the repeating unit (u2), respectively.

[0203] When the resin (A) contains a repeating unit having an acid group, the content of the repeating unit having an acid group is preferably 10 mol% or more, more preferably 15 mol% or more, based on the total repeating units in the resin (A), and the upper limit thereof is preferably 70 mol% or less, more preferably 65 mol% or less, and even more preferably 60 mol% or less, based on the total repeating units in the resin (A).

[0204] The content of repeating units having neither an acid-decomposable group nor an acid group but having a fluorine atom, a bromine atom, or an iodine atom is preferably 0 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on all repeating units in the resin (A), and the upper limit thereof is preferably 50 mol% or less, more preferably 45 mol% or less, and even more preferably 40 mol% or less, based on all repeating units in the resin (A).

[0205] When the resin (A) contains a repeating unit having a lactone group, a sultone group, or a carbonate group, the content of the repeating unit having a lactone group, a sultone group, or a carbonate group is preferably 1 mol% or more, more preferably 10 mol% or more, based on all repeating units in the resin (A), and the upper limit thereof is preferably 85 mol% or less, more preferably 80 mol% or less, even more preferably 70 mol% or less, and particularly preferably 60 mol% or less, based on all repeating units in the resin (A).

[0206] (Repeating Unit for Reducing Mobility of Main Chain) Resin (A) preferably has a high glass transition temperature (Tg) in order to suppress excessive diffusion of generated acid or pattern collapse during development. Tg is preferably higher than 90°C, more preferably higher than 100°C, even more preferably higher than 110°C, and particularly preferably higher than 125°C. In order to achieve an excellent dissolution rate in a developer, Tg is preferably 400°C or lower, more preferably 350°C or lower. In this specification, the glass transition temperature (Tg) of a polymer such as resin (A) (hereinafter referred to as "Tg of repeating unit") is calculated by the following method. First, the Tg of a homopolymer consisting of only each repeating unit contained in the polymer is calculated using the Bicerano method. Next, the mass proportion (%) of each repeating unit relative to all repeating units in the polymer is calculated. Next, the Tg at each mass ratio is calculated using the Fox formula (described in Materials Letters 62 (2008) 3152, etc.), and the sum of these values ​​is used to determine the Tg (°C) of the polymer. The Bicerano method is described in "Prediction of Polymer Properties," Marcel Dekker Inc., New York (1993). Calculation of Tg by the Bicerano method can be performed using polymer property estimation software MDL Polymer (MDL Information Systems, Inc.).

[0207] In order to increase the Tg of resin (A) (preferably to make the Tg greater than 90°C), it is preferable to reduce the mobility of the main chain of resin (A). Methods for reducing the mobility of the main chain of resin (A) include the following methods (a) to (e): (a) Introduction of a bulky substituent into the main chain; (b) Introduction of multiple substituents into the main chain; (c) Introduction of a substituent that induces interactions between resins (A) near the main chain; (d) Formation of a main chain with a cyclic structure; (e) Linking of a cyclic structure to the main chain. It is preferable that resin (A) has a repeating unit that exhibits a homopolymer Tg of 130°C or higher. The type of repeating unit that exhibits a homopolymer Tg of 130°C or higher is not particularly limited, and it is sufficient that the repeating unit exhibits a homopolymer Tg of 130°C or higher as calculated by the Bicerano method. It is to be noted that depending on the type of functional group in the repeating units represented by formulas (A) to (E) described below, it may be considered a repeating unit that exhibits a homopolymer Tg of 130°C or higher.

[0208] One example of a specific means for achieving the above (a) is to introduce a repeating unit represented by formula (A) into resin (A).

[0209]

[0210] Formula (A), R Ａ represents a group containing a polycyclic structure. ｘ represents a hydrogen atom, a methyl group, or an ethyl group. A group containing a polycyclic structure is a group containing multiple ring structures, and the multiple ring structures may be condensed or not condensed. Specific examples of the repeating unit represented by formula (A) include those described in paragraphs

[0107] to

[0119] of WO 2018 / 193954.

[0211] One example of a specific means for achieving the above (b) is to introduce a repeating unit represented by formula (B) into resin (A).

[0212]

[0213] In formula (B), R ｂ１ ~R ｂ４ each independently represents a hydrogen atom or an organic group; R ｂ１ ~R ｂ４At least two of the above represent organic groups. When at least one of the organic groups is a group in which a ring structure is directly linked to the main chain in the repeating unit, the type of the other organic groups is not particularly limited. Furthermore, when none of the organic groups is a group in which a ring structure is directly linked to the main chain in the repeating unit, at least two of the organic groups are substituents having three or more constituent atoms excluding hydrogen atoms. Specific examples of the repeating unit represented by formula (B) include those described in paragraphs

[0113] to

[0115] of WO 2018 / 193954.

[0214] One example of a specific means for achieving the above (c) is to introduce a repeating unit represented by formula (C) into resin (A).

[0215]

[0216] In formula (C), R ｃ１ ~R ｃ４ each independently represents a hydrogen atom or an organic group; R ｃ１ ~R ｃ４ At least one of the repeating units represented by formula (C) is a group containing a hydrogen-bonding hydrogen atom within three atoms from the main chain carbon. In particular, in order to induce interactions between the main chains of resin (A), it is preferable to have a hydrogen-bonding hydrogen atom within two atoms (closer to the main chain). Specific examples of the repeating unit represented by formula (C) include those described in paragraphs

[0119] to

[0121] of WO 2018 / 193954.

[0217] One example of a specific means for achieving the above (d) is to introduce a repeating unit represented by formula (D) into resin (A).

[0218]

[0219] In formula (D), "Cyclic" represents a group that forms a main chain with a cyclic structure. The number of constituent atoms of the ring is not particularly limited. Specific examples of the repeating unit represented by formula (D) include those described in paragraphs

[0126] to

[0127] of WO 2018 / 193954.

[0220] One example of a specific means for achieving the above (e) is to introduce a repeating unit represented by formula (E) into resin (A).

[0221]

[0222] In formula (E), Re each independently represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group, each of which may have a substituent. "Cyclic" refers to a cyclic group containing carbon atoms in the main chain. The number of atoms contained in the cyclic group is not particularly limited. Specific examples of the repeating unit represented by formula (E) include those described in paragraphs

[0131] to

[0133] of WO 2018 / 193954.

[0223] (Repeating unit having at least one group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, a cyano group, and an alkali-soluble group) The resin (A) may have a repeating unit having at least one group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, a cyano group, and an alkali-soluble group. Examples of the repeating unit having a lactone group, a sultone group, or a carbonate group contained in the resin (A) include the repeating units described above in <Repeating unit having a lactone group, a sultone group, or a carbonate group>. The preferred content is also as described above in <Repeating unit having a lactone group, a sultone group, or a carbonate group>.

[0224] The resin (A) may have a repeating unit having a hydroxyl group or a cyano group. This improves substrate adhesion and developer affinity. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group. The repeating unit having a hydroxyl group or a cyano group preferably does not have an acid-decomposable group. Examples of repeating units having a hydroxyl group or a cyano group include those described in paragraphs

[0081] to

[0084] of JP 2014-098921 A.

[0225] The resin (A) may have a repeating unit having an alkali-soluble group. Examples of the alkali-soluble group include a carboxyl group, a sulfonamide group, a sulfonylimide group, a bissulfonylimide group, and an aliphatic alcohol group (e.g., a hexafluoroisopropanol group) substituted at the α-position with an electron-withdrawing group, with a carboxyl group being preferred. When the resin (A) contains a repeating unit having an alkali-soluble group, the resolution in contact hole applications is improved. Examples of repeating units having an alkali-soluble group include those described in paragraphs

[0085] and

[0086] of JP 2014-098921 A.

[0226] (Repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposability) Resin (A) may have a repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposability. This can reduce elution of low-molecular-weight components from the resist film into the immersion liquid during immersion exposure. Examples of repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposability include repeating units derived from 1-adamantyl(meth)acrylate, diamantyl(meth)acrylate, tricyclodecanyl(meth)acrylate, or cyclohexyl(meth)acrylate.

[0227] (Repeating Unit Represented by Formula (III) Having Neither a Hydroxyl Group nor a Cyano Group) The resin (A) may have a repeating unit represented by formula (III) having neither a hydroxyl group nor a cyano group.

[0228]

[0229] In formula (III), R ５ represents a hydrocarbon group having at least one cyclic structure and having neither a hydroxyl group nor a cyano group. Ra represents a hydrogen atom, an alkyl group, or a —CH ２ -O-Ra ２ represents a group. ２ represents a hydrogen atom, an alkyl group, or an acyl group. Examples of the repeating unit represented by formula (III) that does not have either a hydroxyl group or a cyano group include those described in paragraphs

[0087] to

[0094] of JP 2014-098921 A.

[0230] Resin (A) can be synthesized according to a conventional method (e.g., radical polymerization). The weight average molecular weight (Mw) of resin (A), as measured by GPC in terms of polystyrene, is preferably 30,000 or less, more preferably 1,000 to 30,000, even more preferably 3,000 to 30,000, and particularly preferably 5,000 to 15,000. The dispersity (molecular weight distribution, Mw / Mn) of resin (A) is preferably 1 to 5, more preferably 1 to 3, even more preferably 1.2 to 3.0, and particularly preferably 1.2 to 2.0. The smaller the dispersity, the better the resolution and resist shape, and furthermore, the smoother the sidewalls of the resist pattern and the better the roughness.

[0231] The content of resin (A) in the composition of the present invention is preferably 0 to 20 mass %, more preferably 0 to 10 mass %, and even more preferably 0 mass % relative to the total solid content of the composition of the present invention (it is even more preferable that the composition of the present invention does not contain resin (A)). Resin (A) may be used alone or in combination of two or more types. When two or more types are used, it is preferable that the total content thereof is within the above-mentioned preferred content range.

[0232] [Compound (B) that generates an acid upon irradiation with actinic rays or radiation] The composition of the present invention may contain a compound (B) that generates an acid upon irradiation with actinic rays or radiation and is different from the resin (X). The compound (B) is a compound that does not have the repeating unit (u1) described above. The compound (B) is preferably in the form of a low molecular weight compound. The molecular weight of the compound (B) is preferably 5,000 or less, more preferably 4,000 or less, and even more preferably 3,000 or less. There is no particular lower limit for the molecular weight of the compound (B), but it is preferably 100 or more.

[0233] Examples of the compound (B) include "M ＋ X －", and it is preferably a compound that generates an organic acid upon exposure. Examples of the organic acid include sulfonic acids (aliphatic sulfonic acids, aromatic sulfonic acids, camphorsulfonic acids, etc.), carboxylic acids (aliphatic carboxylic acids, aromatic carboxylic acids, aralkyl carboxylic acids, etc.), carbonylsulfonylimide acids, bis(alkylsulfonyl)imide acids, and tris(alkylsulfonyl)methide acids.

[0234] "M ＋ X － In the compound represented by the formula ", M ＋ represents a cation, and preferably represents an organic cation. ＋ Specific examples and preferred ranges of are the same as the specific examples and preferred ranges of the cation contained in the repeating unit (u1) described above.

[0235] "M ＋ X － In the compound represented by the formula "X － represents an anion, preferably an organic anion. The organic anion is not particularly limited, and examples thereof include monovalent or divalent or higher organic anions. The organic anion is preferably an anion having a significantly low ability to cause a nucleophilic reaction, and more preferably a non-nucleophilic anion.

[0236] Examples of non-nucleophilic anions include sulfonate anions (aliphatic sulfonate anions, aromatic sulfonate anions, camphorsulfonate anions, etc.), carboxylate anions (aliphatic carboxylate anions, aromatic carboxylate anions, aralkyl carboxylate anions, etc.), sulfonylimide anions, bis(alkylsulfonyl)imide anions, and tris(alkylsulfonyl)methide anions.

[0237] The aliphatic moiety in the aliphatic sulfonate anion and the aliphatic carboxylate anion may be a linear or branched alkyl group or a cycloalkyl group, and is preferably a linear or branched alkyl group having 1 to 30 carbon atoms or a cycloalkyl group having 3 to 30 carbon atoms. The alkyl group may be, for example, a fluoroalkyl group (which may have a substituent other than a fluorine atom, or may be a perfluoroalkyl group).

[0238] The aryl group in the aromatic sulfonate anion and aromatic carboxylate anion is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a tolyl group, and a naphthyl group.

[0239] The alkyl group, cycloalkyl group, and aryl group mentioned above may have a substituent. The substituent is not particularly limited, but examples thereof include a nitro group, a halogen atom such as a fluorine atom or a chlorine atom, a carboxyl group, a hydroxyl group, an amino group, a cyano group, an alkoxy group (preferably having 1 to 15 carbon atoms), an alkyl group (preferably having 1 to 10 carbon atoms), a cycloalkyl group (preferably having 3 to 15 carbon atoms), an aryl group (preferably having 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably having 2 to 7 carbon atoms), an acyl group (preferably having 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably having 2 to 7 carbon atoms), an alkylthio group (preferably having 1 to 15 carbon atoms), an alkylsulfonyl group (preferably having 1 to 15 carbon atoms), an alkyliminosulfonyl group (preferably having 1 to 15 carbon atoms), and an aryloxysulfonyl group (preferably having 6 to 20 carbon atoms).

[0240] The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 7 to 14 carbon atoms. Examples of the aralkyl group having 7 to 14 carbon atoms include a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylbutyl group.

[0241] An example of the sulfonylimide anion is a saccharin anion.

[0242] The alkyl group in the bis(alkylsulfonyl)imide anion and the tris(alkylsulfonyl)methide anion is preferably an alkyl group having 1 to 5 carbon atoms. Substituents for these alkyl groups include halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, and cycloalkylaryloxysulfonyl groups, with fluorine atoms or alkyl groups substituted with fluorine atoms being preferred. Furthermore, the alkyl groups in the bis(alkylsulfonyl)imide anion may be bonded to each other to form a ring structure, which increases the acid strength.

[0243] Other non-nucleophilic anions include, for example, phosphorus fluorides (e.g., PF ６ － ), boron fluorides (e.g., BF ４ － ), and antimony fluorides (e.g., SbF ６ － ) are listed.

[0244] The non-nucleophilic anion is also preferably an anion represented by the following formula (AN1).

[0245]

[0246] In formula (AN1), R １ and R ２ each independently represents a hydrogen atom or a substituent. The substituent is not particularly limited, but a group that is not an electron-withdrawing group is preferred. Examples of groups that are not electron-withdrawing groups include hydrocarbon groups, hydroxyl groups, oxyhydrocarbon groups, oxycarbonyl hydrocarbon groups, amino groups, hydrocarbon-substituted amino groups, and hydrocarbon-substituted amide groups. Examples of groups that are not electron-withdrawing groups include, each independently, -R', -OH, -OR', -OCOR', -NH ２ , -NR' ２ , —NHR′, or —NHCOR′ is preferred, where R′ is a monovalent hydrocarbon group.

[0247] Examples of the monovalent hydrocarbon group represented by R' include monovalent linear or branched hydrocarbon groups such as alkyl groups such as methyl, ethyl, propyl, and butyl; alkenyl groups such as ethenyl, propenyl, and butenyl; alkynyl groups such as ethynyl, propynyl, and butynyl; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, and adamantyl; monovalent alicyclic hydrocarbon groups such as cycloalkenyl groups such as cyclopropenyl, cyclobutenyl, cyclopentenyl, and norbornenyl; aryl groups such as phenyl, tolyl, xylyl, mesityl, naphthyl, methylnaphthyl, anthryl, and methylanthryl; and aralkyl groups such as benzyl, phenethyl, phenylpropyl, naphthylmethyl, and anthrylmethyl. Among these, R １ and R ２ are each independently preferably a hydrocarbon group (preferably a cycloalkyl group) or a hydrogen atom.

[0248] L represents a divalent linking group. When a plurality of L's are present, they may be the same or different. Examples of the divalent linking group include -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -S-, -SO-, and -SO ２ Examples of the divalent linking group include -, an alkylene group (preferably having 1 to 6 carbon atoms), a cycloalkylene group (preferably having 3 to 15 carbon atoms), an alkenylene group (preferably having 2 to 6 carbon atoms), and a divalent linking group formed by combining a plurality of these groups. Among these, examples of the divalent linking group include -O-CO-O-, -COO-, -CONH-, -CO-, -O-, and -SO ２ -, -O-CO-O-alkylene group-, -COO-alkylene group-, or -CONH-alkylene group- is preferred, and -O-CO-O-, -O-CO-O-alkylene group-, -COO-, -CONH-, or -SO ２ - or -COO-alkylene group- is more preferred.

[0249] As L, for example, a group represented by the following formula (AN1-1) is preferable: ａ - (CR２ａ ２ ) Ｘ -Q-(CR ２ｂ ２ ) Ｙ -* ｂ (AN1-1)

[0250] In formula (AN1-1), * ａ is R in formula (AN1). ３ Represents the bonding position with * ｂ represents -C(R １ ) (R ２ X and Y each independently represent an integer of 0 to 10, preferably an integer of 0 to 3. R ２ａ and R ２ｂ R each independently represents a hydrogen atom or a substituent. ２ａ and R ２ｂ When there are multiple R ２ａ and R ２ｂ may be the same or different, provided that when Y is 1 or more, -C(R １ ) (R ２ )- and CR directly bonded ２ｂ ２ R in ２ｂ is other than a fluorine atom. Q is * Ａ -O-CO-O-* Ｂ , * Ａ -CO-* Ｂ , * Ａ -CO-O-* Ｂ , * Ａ -O-CO-* Ｂ , * Ａ -O-* Ｂ , * Ａ -S-* Ｂ , or * Ａ -SO ２ -* Ｂ where X+Y in formula (AN1-1) is 1 or more, and R ２ａ and R ２ｂ are all hydrogen atoms, Q is * Ａ -O-CO-O-* Ｂ , * Ａ -CO-*Ｂ , * Ａ -O-CO-* Ｂ , * Ａ -O-* Ｂ , * Ａ -S-* Ｂ , or * Ａ -SO ２ -* Ｂ Represents. Ａ is R in formula (AN1). ３ represents the bonding position on the side, and * Ｂ represents -SO in formula (AN1). ３ － represents the bonding position on the side.

[0251] In formula (AN1), R ３ represents an organic group. The organic group is not particularly limited as long as it has one or more carbon atoms, and may be a linear group (for example, a linear alkyl group), a branched group (for example, a branched alkyl group such as a t-butyl group), or a cyclic group. The organic group may or may not have a substituent. The organic group may or may not have a heteroatom (such as an oxygen atom, a sulfur atom, and / or a nitrogen atom).

[0252] Among them, R ３is preferably an organic group having a cyclic structure. The cyclic structure may be monocyclic or polycyclic and may have a substituent. The ring in the organic group having a cyclic structure is preferably directly bonded to L in formula (AN1). The organic group having a cyclic structure may or may not have a heteroatom (oxygen atom, sulfur atom, and / or nitrogen atom, etc.). The heteroatom may be substituted for one or more of the carbon atoms forming the cyclic structure. The organic group having a cyclic structure is preferably, for example, a hydrocarbon group having a cyclic structure, a lactone ring group, or a sultone ring group. Among these, the organic group having a cyclic structure is preferably a hydrocarbon group having a cyclic structure. The hydrocarbon group having a cyclic structure is preferably a monocyclic or polycyclic cycloalkyl group. These groups may have a substituent. The cycloalkyl group may be monocyclic (e.g., a cyclohexyl group) or polycyclic (e.g., an adamantyl group), and preferably has 5 to 12 carbon atoms. As the lactone group and sultone group, for example, a group in which one hydrogen atom has been removed from a ring atom constituting the lactone structure or sultone structure in any of the structures represented by the above-mentioned formulae (LC1-1) to (LC1-21) and the structures represented by the above-mentioned formulae (SL1-1) to (SL1-3) is preferred.

[0253] The non-nucleophilic anion may be a benzenesulfonate anion, and is preferably a benzenesulfonate anion substituted with a branched alkyl group or a cycloalkyl group.

[0254] The non-nucleophilic anion is also preferably an anion represented by the following formula (AN2).

[0255]

[0256] In formula (AN2), o represents an integer of 1 to 3. p represents an integer of 0 to 10. q represents an integer of 0 to 10.

[0257] Xf represents a hydrogen atom, a fluorine atom, an alkyl group substituted with at least one fluorine atom, or an organic group having no fluorine atoms. The number of carbon atoms in this alkyl group is preferably 1 to 10, more preferably 1 to 4. The alkyl group substituted with at least one fluorine atom is preferably a perfluoroalkyl group. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, and is preferably a fluorine atom or CF ３ It is more preferable that both Xf's are fluorine atoms.

[0258] R ４ and R ５ R each independently represents a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. ４ and R ５ If there are multiple R ４ and R ５ may be the same or different. ４ and R ５ The alkyl group represented by the formula (I) preferably has 1 to 4 carbon atoms. The alkyl group may have a substituent. ４ and R ５ is preferably a hydrogen atom.

[0259] L represents a divalent linking group, and is defined the same as L in formula (AN1).

[0260] W represents an organic group containing a cyclic structure. Among these, a cyclic organic group is preferred. Examples of the cyclic organic group include an alicyclic group, an aryl group, and a heterocyclic group. The alicyclic group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic group include a monocyclic cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include a polycyclic cycloalkyl group such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. Among these, alicyclic groups having a bulky structure with 7 or more carbon atoms, such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group, are preferred.

[0261] The aryl group may be monocyclic or polycyclic. Examples of the aryl group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group. The heterocyclic group may be monocyclic or polycyclic. In particular, a polycyclic heterocyclic group can further suppress the diffusion of acid. The heterocyclic group may or may not have aromaticity. Examples of heterocyclic rings having aromaticity include a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Examples of heterocyclic rings having no aromaticity include a tetrahydropyran ring, a lactone ring, a sultone ring, and a decahydroisoquinoline ring. The heterocyclic ring in the heterocyclic group is preferably a furan ring, a thiophene ring, a pyridine ring, or a decahydroisoquinoline ring.

[0262] The cyclic organic group may have a substituent. Examples of the substituent include an alkyl group (which may be either linear or branched, and preferably has 1 to 12 carbon atoms), a cycloalkyl group (which may be either monocyclic, polycyclic, or spirocyclic, and preferably has 3 to 20 carbon atoms), an aryl group (which preferably has 6 to 14 carbon atoms), a hydroxyl group, an alkoxy group, an ester group, an amide group, a urethane group, a ureido group, a thioether group, a sulfonamide group, and a sulfonate ester group. The carbon constituting the cyclic organic group (the carbon that contributes to ring formation) may be a carbonyl carbon.

[0263] The anion represented by formula (AN2) is SO ３ － -CF ２ -CH ２ -OCO-(L) ｑ’ -W, SO ３ － -CF ２ -CHF-CH ２ -OCO-(L) ｑ’ -W, SO ３ － -CF ２ -COO-(L) ｑ’ -W, SO ３ － -CF ２ -CF ２ -CH ２ -CH ２ - (L) ｑ -W or SO ３ － -CF ２ -CH(CF ３ ) -OCO-(L) ｑ’ -W is preferred. Here, L, q and W are the same as those in formula (AN2). q' represents an integer of 0 to 10.

[0264] The non-nucleophilic anion is also preferably an aromatic sulfonate anion represented by the following formula (AN3).

[0265]

[0266] In formula (AN3), Ar represents an aryl group (such as a phenyl group) and may further have a substituent other than the sulfonate anion and the -(D-B) group. Examples of the substituent that may further be had include a fluorine atom and a hydroxyl group. n represents an integer of 0 or greater. n is preferably 1 to 4, more preferably 2 to 3, and even more preferably 3.

[0267] D represents a single bond or a divalent linking group. Examples of the divalent linking group include an ether group, a thioether group, a carbonyl group, a sulfoxide group, a sulfone group, a sulfonate ester group, an ester group, and a group formed by combining two or more of these groups.

[0268] B represents a hydrocarbon group. B is preferably an aliphatic hydrocarbon group, and more preferably an isopropyl group, a cyclohexyl group, or an aryl group which may further have a substituent (such as a tricyclohexylphenyl group).

[0269] As the non-nucleophilic anion, a disulfonamide anion is also preferred. The disulfonamide anion is, for example, N － (SO ２ -R ｑ ) ２ where R ｑ represents an alkyl group which may have a substituent, preferably a fluoroalkyl group, more preferably a perfluoroalkyl group. ｑ may be bonded to each other to form a ring. ｑ The group formed by bonding together is preferably an alkylene group which may have a substituent, more preferably a fluoroalkylene group, and even more preferably a perfluoroalkylene group. The alkylene group preferably has 2 to 4 carbon atoms.

[0270] It is also preferable that the compound (B) is at least one selected from the group consisting of the compounds (I) to (II).

[0271] (Compound (I)) Compound (I) is a compound having one or more structural moieties X and one or more structural moieties Y, which generates an acid containing the first acidic moiety derived from the structural moiety X and the second acidic moiety derived from the structural moiety Y when irradiated with actinic rays or radiation. Structural moiety X: Anionic moiety A １ － and the cationic moiety M １ ＋ and by irradiation with actinic rays or radiation, HA １ Structural moiety Y: anionic moiety A, which forms a first acidic moiety represented by the formula: ２ － and the cationic moiety M ２ ＋ and by irradiation with actinic rays or radiation, HA ２ The compound (I) satisfies the following condition I:

[0272] Condition I: In the compound (I), the cationic moiety M in the structural moiety X １ ＋ and the cationic moiety M in the structural moiety Y ２ ＋ H ＋ The compound PI in which the cation moiety M in the structural moiety X is replaced by １ ＋ H ＋ HA is replaced by １ and the cationic moiety M in the structural moiety Y. ２ ＋ H ＋ HA is replaced by ２ and an acid dissociation constant a2 derived from the acidic site represented by the formula (I), and the acid dissociation constant a2 is greater than the acid dissociation constant a1.

[0273] Condition I will be explained in more detail below. For example, when compound (I) is an acid-generating compound having one of the first acidic sites derived from the structural moiety X and one of the second acidic sites derived from the structural moiety Y, compound PI is "HA １ and H.A.２ The acid dissociation constant a1 and the acid dissociation constant a2 of the compound PI correspond to "a compound having the following structure." More specifically, when the acid dissociation constant of the compound PI is calculated, the acid dissociation constant a1 and the acid dissociation constant a2 of the compound PI correspond to "a compound having the following structure." １ － and H.A. ２ The pKa at which the compound becomes "a compound having the above formula (A)" is the acid dissociation constant a1, １ － and H.A. ２ "A compound having １ － and A ２ － The pKa at which the compound becomes "a compound having the above formula (I)" is the acid dissociation constant a2.

[0274] For example, when compound (I) is an acid-generating compound having two of the first acidic sites derived from the structural site X and one of the second acidic sites derived from the structural site Y, compound PI is a compound having two HAs. １ and one HA ２ When the acid dissociation constant of compound PI is calculated, compound PI corresponds to "a compound having one A １ － and one HA １ and one HA ２ and the acid dissociation constant when "a compound having one A １ － and one HA １ and one HA ２ "Compound having two A １ － and one HA ２ The acid dissociation constant when the compound is a compound having two A's corresponds to the acid dissociation constant a1 described above. １ － and one HA ２ "Compound having two A １ － and A ２ － In other words, in the case of compound PI, the acid dissociation constant when the compound becomes a compound having the cation moiety M in the structural moiety X corresponds to the acid dissociation constant a2. １ ＋ H ＋ HA is replaced by１ When the compound PI has a plurality of acid dissociation constants derived from the acidic moiety represented by the formula (I), the value of the acid dissociation constant a2 is larger than the largest value of the plurality of acid dissociation constants a1. １ － and one HA １ and one HA ２ The acid dissociation constant when the compound is aa is defined as "a compound having one A １ － and one HA １ and one HA ２ "Compound having two A １ － and one HA ２ When the acid dissociation constant when the compound becomes "a compound having the formula (I)" is ab, the relationship between aa and ab satisfies aa<ab.

[0275] The acid dissociation constants a1 and a2 are determined by the above-mentioned method for measuring an acid dissociation constant. The compound PI corresponds to an acid generated when compound (I) is irradiated with actinic rays or radiation. When compound (I) has two or more structural moieties X, the structural moieties X may be the same or different. In addition, when two or more of the above A １ － and two or more of the above M １ ＋ In compound (I), the above A １ － and the above A ２ － , and the above M １ ＋ and the above M ２ ＋ may be the same or different, but １ － and the above A ２ － are preferably different from each other.

[0276] In the compound PI, the difference (absolute value) between the acid dissociation constant a1 (the maximum value when there are multiple acid dissociation constants a1) and the acid dissociation constant a2 is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1.0 or more. The upper limit of the difference (absolute value) between the acid dissociation constant a1 (the maximum value when there are multiple acid dissociation constants a1) and the acid dissociation constant a2 is not particularly limited, but is, for example, 16 or less.

[0277] In the compound PI, the acid dissociation constant a2 is preferably not more than 20, more preferably not more than 15. The lower limit of the acid dissociation constant a2 is preferably not less than −4.0.

[0278] In the compound PI, the acid dissociation constant a1 is preferably 2.0 or less, and more preferably 0 or less. The lower limit of the acid dissociation constant a1 is preferably −20.0 or more.

[0279] Anion site A １ － and anionic moiety A ２ － is a structural moiety containing a negatively charged atom or atomic group, and examples thereof include structural moieties selected from the group consisting of formulae (AA-1) to (AA-3) and formulae (BB-1) to (BB-6) shown below. １ － As the anionic moiety A, those capable of forming an acidic moiety with a small acid dissociation constant are preferred, and among these, any of formulas (AA-1) to (AA-3) is more preferred, and any of formulas (AA-1) and (AA-3) is even more preferred. ２ － As the anion moiety A １ － Preferably, it is one that can form an acidic site with a larger acid dissociation constant than the above, more preferably any of formulas (BB-1) to (BB-6), and even more preferably any of formulas (BB-1) and (BB-4). In the following formulas (AA-1) to (AA-3) and formulas (BB-1) to (BB-6), * represents a bonding position. In formula (AA-2), R Ａ represents a monovalent organic group. ＡThe monovalent organic group represented by the formula (I) is not particularly limited, but examples thereof include a cyano group, a trifluoromethyl group, and a methanesulfonyl group.

[0280]

[0281]

[0282] Cationic moiety M １ ＋ and cationic moiety M ２ ＋ is a structural moiety containing a positively charged atom or atomic group, and examples thereof include monovalent organic cations. ＋ Examples of the organic cation include:

[0283] (Compound (II)) Compound (II) is a compound having two or more of the above structural moieties X and one or more of the following structural moieties Z, which generates an acid containing two or more of the first acidic moieties derived from the structural moiety X and the structural moiety Z upon irradiation with actinic rays or radiation. Structural moiety Z: a ​​nonionic moiety capable of neutralizing an acid

[0284] In compound (II), the definition of the structural moiety X and A １ － and M １ ＋ The definition of the structural moiety X in the compound (I) and the definition of A １ － and M １ ＋ The definition and preferred embodiments are also the same as those given above.

[0285] In the compound (II), the cationic moiety M in the structural moiety X １ ＋ H ＋ In the compound PII, the cationic moiety M in the structural moiety X is replaced by １ ＋ H ＋ HA is replaced by １The preferred range of the acid dissociation constant a1 derived from the acidic moiety represented by the formula (I) is the same as the acid dissociation constant a1 in the compound PI. In addition, when the compound (II) is, for example, a compound that generates an acid having two of the first acidic moieties derived from the structural moiety X and the structural moiety Z, the compound PII is a compound that generates an acid having two HAs. １ When the acid dissociation constant of this compound PII was calculated, it was found that the compound PII has "one A １ － and one HA １ and the acid dissociation constant when "a compound having one A １ － and one HA １ "Compound having two A １ － The acid dissociation constant when the compound becomes "a compound having the formula (I)" corresponds to the acid dissociation constant a1.

[0286] The acid dissociation constant a1 is determined by the above-mentioned method for measuring an acid dissociation constant. The compound PII corresponds to the acid generated when the compound (II) is irradiated with actinic rays or radiation. The two or more structural moieties X may be the same or different. １ － and two or more of the above M １ ＋ may be the same or different.

[0287] The nonionic moiety capable of neutralizing an acid in the structural moiety Z is not particularly limited, and is preferably, for example, a moiety containing a group capable of electrostatically interacting with a proton or a functional group having electrons. Examples of the group capable of electrostatically interacting with a proton or the functional group having electrons include functional groups having a macrocyclic structure such as cyclic polyethers, and functional groups having a nitrogen atom with an unshared electron pair that does not contribute to π-conjugation. The nitrogen atom with an unshared electron pair that does not contribute to π-conjugation is, for example, a nitrogen atom having a partial structure shown in the following formula:

[0288]

[0289] Examples of the partial structure of a functional group having a group or electron capable of electrostatically interacting with a proton include a crown ether structure, an azacrown ether structure, a primary amine structure, a secondary amine structure, a tertiary amine structure, a pyridine structure, an imidazole structure, and a pyrazine structure. Of these, a primary amine structure, a secondary amine structure, a tertiary amine structure, and a tertiary amine structure are preferred.

[0290] Examples of moieties other than cations that Compound (I) and Compound (II) may have are shown below.

[0291]

[0292]

[0293] Specific examples of compound (B) include the compounds described in paragraphs

[0320] to

[0321] of WO 2022 / 172715. The above descriptions are incorporated herein by reference.

[0294] The content of compound (B) in the composition of the present invention is preferably 0 to 20 mass %, more preferably 0 to 10 mass %, and even more preferably 0 mass % relative to the total solid content of the composition of the present invention (it is even more preferable that the composition of the present invention does not contain compound (B)). Compound (B) may be used alone, or two or more types may be used. When two or more types are used, it is preferable that the total content thereof is within the above-mentioned suitable content range.

[0295] [Acid Diffusion Controller] The composition of the present invention may contain an acid diffusion controller. The type of acid diffusion controller is not particularly limited, and examples thereof include a basic compound (DA), a low-molecular-weight compound (DB) having a nitrogen atom and a group that is cleaved by the action of an acid, and a compound (DC) whose acid diffusion control ability is reduced or eliminated by irradiation with actinic rays or radiation. Examples of the compound (DC) include an onium salt compound (DD) that is a weaker acid relative to the photoacid generator, and a basic compound (DE) whose basicity is reduced or eliminated by irradiation with actinic rays or radiation. Specific examples of the basic compound (DA) include those described in paragraphs

[0132] to

[0136] of WO 2020 / 066824, and specific examples of the basic compound (DE) whose basicity is reduced or eliminated by irradiation with actinic rays or radiation include those described in paragraphs

[0137] to

[0155] of WO 2020 / 066824, and those described in paragraph

[0164] of WO 2020 / 066824. Specific examples of low molecular weight compounds (DB) having a nitrogen atom and having a group that leaves under the action of an acid include those described in paragraphs

[0156] to

[0163] of WO 2020 / 066824. Specific examples of the onium salt compound (DD) that is a weaker acid than the photoacid generator include those described in paragraphs

[0305] to

[0314] of WO 2020 / 158337.

[0296] In addition to the above, for example, known compounds disclosed in paragraphs

[0627] to

[0664] of U.S. Patent Application Publication No. 2016 / 0070167A1, paragraphs

[0095] to

[0187] of U.S. Patent Application Publication No. 2015 / 0004544A1, paragraphs

[0403] to

[0423] of U.S. Patent Application Publication No. 2016 / 0237190A1, and paragraphs

[0259] to

[0328] of U.S. Patent Application Publication No. 2016 / 0274458A1 can be suitably used as the acid diffusion controller.

[0297] The composition of the present invention may or may not contain an acid diffusion controller. The content of the acid diffusion controller in the composition of the present invention is not particularly limited, and may be, for example, 0 to 50% by mass, 0 to 40% by mass, or 0 to 30% by mass, based on the total solid content of the composition of the present invention.

[0298] [Hydrophobic Resin] The composition of the present invention may contain a hydrophobic resin (also referred to as "hydrophobic resin (D)") different from resin (X) and resin (A). The hydrophobic resin (D) is preferably designed so as to be unevenly distributed on the surface of the resist film, but unlike surfactants, it does not necessarily have to have a hydrophilic group in its molecule, and it does not necessarily have to contribute to uniform mixing of polar and non-polar substances. Effects of adding hydrophobic resin (D) include control of the static and dynamic contact angles of water on the resist film surface and suppression of outgassing.

[0299] The hydrophobic resin (D) contains fluorine atoms, silicon atoms, and CH atoms contained in the side chain portion of the resin in order to be unevenly distributed on the surface layer of the film. ３ It is preferable to have one or more of the partial structures, and more preferably two or more. The hydrophobic resin preferably has a hydrocarbon group having 5 or more carbon atoms. These groups may be present in the main chain of the resin or may be substituted on a side chain. Examples of the hydrophobic resin (D) include the compounds described in paragraphs

[0275] to

[0279] of WO 2020 / 004306.

[0300] The content of the hydrophobic resin (D) in the composition of the present invention is preferably 0 to 20 mass %, more preferably 0 to 10 mass %, and even more preferably 0 mass % relative to the total solid content of the composition of the present invention (it is even more preferable that the composition of the present invention does not contain a hydrophobic resin (D)). The hydrophobic resin (D) may be used alone or in combination of two or more. When two or more types are used, it is preferable that the total content thereof is within the above-mentioned preferred content range.

[0301] [Surfactant] The composition of the present invention may contain a surfactant. When a surfactant is contained, a pattern with better adhesion and fewer development defects can be formed. The surfactant is a compound different from the resin (X). The surfactant is preferably a fluorine-based and / or silicon-based surfactant. Examples of the fluorine-based and / or silicon-based surfactant include the surfactants disclosed in paragraphs

[0218] and

[0219] of WO 2018 / 193954.

[0302] The content of the surfactant in the composition of the present invention is preferably 0 to 5 mass %, more preferably 0 to 1 mass %, and even more preferably 0 mass % relative to the total solid content of the composition of the present invention (it is even more preferable that the composition of the present invention does not contain a surfactant). One type of surfactant may be used alone, or two or more types may be used. When two or more types are used, it is preferable that the total content thereof is within the above-mentioned preferred content range.

[0303] [Solvent] The composition of the present invention preferably contains a solvent. The solvent preferably contains (M1) propylene glycol monoalkyl ether carboxylate and (M2) at least one selected from the group consisting of propylene glycol monoalkyl ether, lactate ester, acetate ester, alkoxypropionate ester, linear ketone, cyclic ketone, lactone, and alkylene carbonate. The solvent may further contain components other than components (M1) and (M2).

[0304] Combining the above-mentioned solvent with the above-mentioned resin is preferable in terms of improving the coatability of the composition of the present invention and reducing the number of development defects in the pattern. The above-mentioned solvent has a good balance of the solubility, boiling point, and viscosity of the above-mentioned resin, and therefore can suppress unevenness in the film thickness of the resist film and the occurrence of precipitates during spin coating. Details of component (M1) and component (M2) are described in paragraphs

[0218] to

[0226] of WO 2020 / 004306, the contents of which are incorporated herein by reference.

[0305] When the solvent further contains components other than the components (M1) and (M2), the content of the components other than the components (M1) and (M2) is preferably 5 to 30 mass % based on the total amount of the solvent.

[0306] The content of the solvent in the composition of the present invention is preferably determined so that the solids concentration is 0.5 to 30% by mass, more preferably 1 to 20% by mass, which further improves the coatability of the composition of the present invention.

[0307] [Other Additives] The composition of the present invention may further contain a dissolution inhibiting compound, a dye, a plasticizer, a photosensitizer, a light absorber, and / or a compound that promotes solubility in a developer (for example, a phenol compound having a molecular weight of 1,000 or less, or an alicyclic or aliphatic compound containing a carboxyl group).

[0308] The "dissolution inhibiting compound" is a compound having a molecular weight of 3,000 or less, which is decomposed by the action of an acid and has a reduced solubility in an organic developer.

[0309] The composition of the present invention preferably satisfies at least one of the following conditions (i) and (ii), and more preferably satisfies the following condition (ii): Condition (i): The composition of the present invention contains an acid diffusion controller that is a compound different from the resin (X); and Condition (ii): The resin (X) has a repeating unit that has acid diffusion control ability.

[0310] The composition of the present invention is also suitable as a photosensitive composition for EUV exposure.

[0311] The present invention also relates to an actinic ray-sensitive or radiation-sensitive resin composition containing a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one type of cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change under the action of an acid, and the structure after the structural change has a larger peak area in its absorption spectrum for light with a wavelength of 300 nm to 450 nm than the peak area in the absorption spectrum for light with a wavelength of 300 nm to 450 nm of the structure before the structural change, and the content of the repeating unit (u1) is 40 mass% or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

[0312] The present invention also relates to an actinic ray-sensitive or radiation-sensitive resin composition containing a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one type of cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change under the action of an acid to produce a ketone compound, and the content of the repeating unit (u1) is 40 mass% or more relative to the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

[0313] <Actinic ray- or radiation-sensitive film, pattern forming method> The present invention also relates to an actinic ray- or radiation-sensitive film formed from the composition of the present invention. The actinic ray- or radiation-sensitive film of the present invention is preferably a resist film. The procedure of the pattern forming method using the composition of the present invention is not particularly limited, but preferably includes the following steps: Step 1: forming a resist film on a substrate using the composition of the present invention; Step 2: irradiating the resist film with a first actinic ray or radiation; Step 3: irradiating the resist film after the irradiation with the first actinic ray or radiation with a second actinic ray or radiation; and Step 4: developing the resist film after the irradiation with the second actinic ray or radiation using a developer.

[0314] The procedures for each of the above steps will be described in detail below.

[0315] (Step 1: Resist Film Forming Step) Step 1 is a step of forming a resist film on a substrate using the composition of the present invention.

[0316] A method for forming a resist film on a substrate using the composition of the present invention includes, for example, applying the composition of the present invention to a substrate. It is preferable to filter the composition of the present invention before application, if necessary. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.03 μm or less. The filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon.

[0317] The composition of the present invention can be applied onto a substrate (e.g., silicon, silicon coated with silicon dioxide) such as those used in the manufacture of integrated circuit elements by an appropriate application method such as a spinner or coater. Spin application using a spinner is preferred. The rotation speed when spin application using a spinner is preferably 1,000 to 3,000 rpm (rotations per minute). After application of the composition of the present invention, the substrate may be dried to form a resist film. If necessary, various underlayer films (inorganic films, organic films, anti-reflective films, etc.) may be formed below the resist film.

[0318] An example of a drying method is a method of drying by heating. Heating can be performed by means provided in a normal exposure machine and / or developing machine, and may also be performed using a hot plate or the like. The heating temperature is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The heating time is preferably 30 to 1,000 seconds, more preferably 60 to 800 seconds, and even more preferably 60 to 600 seconds.

[0319] The thickness of the resist film is not particularly limited, but is preferably 10 to 120 nm from the viewpoint of forming a finer pattern with higher precision. In particular, when EUV exposure is used, the thickness of the resist film is more preferably 10 to 65 nm, and even more preferably 15 to 50 nm. When ArF immersion exposure is used, the thickness of the resist film is more preferably 10 to 120 nm, and even more preferably 15 to 90 nm.

[0320] A top coat may be formed on the resist film using a top coat composition. It is preferable that the top coat composition does not mix with the resist film and can be uniformly applied to the resist film. The top coat is not particularly limited, and a conventionally known top coat can be formed by a conventionally known method. For example, a top coat can be formed based on the description in paragraphs

[0072] to

[0082] of JP 2014-059543 A. For example, a top coat containing a basic compound such as that described in JP 2013-61648 A is preferably formed on the resist film. Specific examples of basic compounds that may be contained in the top coat include the basic compounds that may be contained in the composition of the present invention. It is also preferable that the top coat contain a compound containing at least one group or bond selected from the group consisting of an ether bond, a thioether bond, a hydroxyl group, a thiol group, a carbonyl bond, and an ester bond.

[0321] (Step 2: First Exposure Step) Step 2 is a step of irradiating the resist film with first actinic rays or radiation. Examples of exposure methods include irradiating the formed resist film with actinic rays or radiation through a predetermined mask. Examples of actinic rays or radiation (first actinic rays or radiation) used in Step 2 include infrared rays, visible rays, ultraviolet rays, far ultraviolet rays, extreme ultraviolet rays, X-rays, and electron beams. The wavelength of the first actinic rays or radiation is preferably shorter than the wavelength of the second actinic rays or radiation. The wavelength of the first actinic rays or radiation is preferably 250 nm or less, more preferably 220 nm or less, and even more preferably 1 to 200 nm. Specific examples of the first actinic rays or radiation include KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ２Excimer laser (157 nm), EUV (13.5 nm), X-rays or electron beams are preferred, and electron beams or extreme ultraviolet rays are more preferred.

[0322] After exposure, it is preferable to bake (heat) the film before developing. Baking promotes the reaction of the exposed areas, resulting in better sensitivity and pattern shape. The heating temperature is preferably 23 to 130°C, more preferably 23 to 110°C, and even more preferably 23 to 90°C. The heating time is preferably 10 to 1,000 seconds, more preferably 10 to 180 seconds, and even more preferably 30 to 120 seconds. Heating can be performed using means provided in a typical exposure machine and / or development machine, and may also be performed using a hot plate or the like. This process is also called post-exposure baking.

[0323] (Step 3: Second Exposure Step) Step 3 is a step of irradiating the resist film after irradiation with the first actinic ray or radiation with a second actinic ray or radiation. Examples of the exposure method include a method of irradiating the entire surface of the resist film after irradiation with the first actinic ray or radiation with actinic ray or radiation. Examples of the actinic ray or radiation (second actinic ray or radiation) used in Step 3 include infrared light, visible light, ultraviolet light, and far ultraviolet light, with ultraviolet light being preferred. The wavelength of the second actinic ray or radiation is preferably 350 nm to 450 nm.

[0324] After exposure, it is preferable to bake (heat) the film before developing. Baking promotes the reaction of the exposed areas, resulting in better sensitivity and pattern shape. The heating temperature is preferably 70 to 150°C, more preferably 70 to 140°C, and even more preferably 70 to 130°C. The heating time is preferably 10 to 1,000 seconds, more preferably 10 to 180 seconds, and even more preferably 30 to 120 seconds. Heating can be carried out using means provided in a normal exposure machine and / or development machine, and may also be carried out using a hot plate or the like. This process is also called post-exposure baking.

[0325] (Step 4: Development Step) Step 4 is a step of developing the resist film after irradiation with the second actinic ray or radiation using a developer. By performing Step 4, a pattern is formed. The developer may be an alkaline developer or a developer containing an organic solvent (hereinafter also referred to as an organic developer).

[0326] Examples of development methods include a method in which a substrate is immersed in a tank filled with a developer for a certain period of time (dip method), a method in which a developer is piled up on the surface of a substrate by surface tension and left to stand for a certain period of time for development (puddle method), a method in which a developer is sprayed onto the surface of the substrate (spray method), and a method in which a developer is continuously dispensed onto a substrate rotating at a constant speed while a developer dispense nozzle is scanned at a constant speed (dynamic dispense method). Furthermore, after the development step, a step of stopping development while replacing the solvent with another solvent may be carried out. The development time is not particularly limited as long as it is long enough to sufficiently dissolve the resin in the unexposed areas, and is preferably 10 to 300 seconds, more preferably 20 to 120 seconds. The temperature of the developer is preferably 0 to 50°C, more preferably 15 to 35°C.

[0327] The alkaline developer is preferably an aqueous alkaline solution containing an alkali. The type of alkaline aqueous solution is not particularly limited, but examples include aqueous alkaline solutions containing a quaternary ammonium salt, such as tetramethylammonium hydroxide, an inorganic alkali, a primary amine, a secondary amine, a tertiary amine, an alcohol amine, or a cyclic amine. Of these, the alkaline developer is preferably an aqueous solution of a quaternary ammonium salt, such as tetramethylammonium hydroxide (TMAH). Appropriate amounts of alcohols, surfactants, and the like may be added to the alkaline developer. The alkaline concentration of the alkaline developer is usually preferably 0.1 to 20% by mass. The pH of the alkaline developer is usually preferably 10.0 to 15.0.

[0328] The organic developer is preferably a developer containing at least one organic solvent selected from the group consisting of ketone-based solvents, ester-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents.

[0329] The above-mentioned solvents may be mixed in plural, or may be mixed with a solvent other than the above or water. The water content of the developer as a whole is preferably less than 50% by mass, more preferably less than 20% by mass, even more preferably less than 10% by mass, and particularly preferably substantially free of water. The content of the organic solvent in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and particularly preferably 95% by mass or more and 100% by mass or less, based on the total amount of the developer.

[0330] (Other Steps) The pattern formation method preferably includes, after step 3, a step of cleaning with a rinse liquid.

[0331] The rinse liquid used in the rinse step after the development step using an alkaline developer can be, for example, pure water. A suitable amount of surfactant may be added to the pure water. A suitable amount of surfactant may be added to the rinse liquid.

[0332] The rinse liquid used in the rinse step after the development step using an organic developer is not particularly limited as long as it does not dissolve the pattern, and a solution containing a general organic solvent can be used. The rinse liquid is preferably a rinse liquid containing at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents.

[0333] The method for the rinsing step is not particularly limited, and examples include a method in which a rinsing solution is continuously discharged onto a substrate rotating at a constant speed (spin coating method), a method in which a substrate is immersed in a tank filled with the rinsing solution for a certain period of time (dipping method), and a method in which the rinsing solution is sprayed onto the substrate surface (spray method). The pattern formation method may also include a heating step (post-bake) after the rinsing step. This step removes the developer and rinsing solution remaining between and within the pattern by baking. This step also has the effect of annealing the resist pattern and improving the surface roughness of the pattern. The heating step after the rinsing step is typically performed at 40 to 250°C (preferably 90 to 200°C) for typically 10 seconds to 3 minutes (preferably 30 to 120 seconds).

[0334] Alternatively, the substrate may be etched using the formed pattern as a mask. That is, the substrate (or the underlayer film and the substrate) may be processed using the pattern formed in step 3 as a mask to form a pattern on the substrate. The method for processing the substrate (or the underlayer film and the substrate) is not particularly limited, but a method of forming a pattern on the substrate by dry etching the substrate (or the underlayer film and the substrate) using the pattern formed in step 3 as a mask is preferred. The dry etching is preferably oxygen plasma etching.

[0335] The composition of the present invention and various materials used in the pattern formation method (e.g., solvents, developers, rinse solutions, anti-reflective coating compositions, top coat compositions, etc.) preferably do not contain impurities such as metals. The content of impurities contained in these materials is preferably 1 mass ppm (parts per million) or less, more preferably 10 mass ppb (parts per billion) or less, even more preferably 100 mass ppt or less, particularly preferably 10 mass ppt or less, and most preferably 1 mass ppt or less. There is no particular lower limit, and 0 mass ppt or more is preferred. Here, examples of metal impurities include Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn.

[0336] Examples of methods for removing impurities such as metals from various materials include filtration using a filter. Details of filtration using a filter are described in paragraph

[0321] of WO 2020 / 004306.

[0337] Methods for reducing impurities such as metals contained in various materials include, for example, selecting raw materials with a low metal content as raw materials for the various materials, filtering the raw materials for the various materials, and performing distillation under conditions that minimize contamination as much as possible, for example by lining the inside of the apparatus with Teflon (registered trademark).

[0338] In addition to filter filtration, impurities may be removed using an adsorbent, or a combination of filter filtration and an adsorbent may be used. Known adsorbents can be used as the adsorbent, including inorganic adsorbents such as silica gel and zeolite, and organic adsorbents such as activated carbon. In order to reduce impurities such as metals contained in the various materials, it is necessary to prevent the incorporation of metal impurities during the manufacturing process. Whether metal impurities have been sufficiently removed from the manufacturing equipment can be confirmed by measuring the content of metal components contained in the cleaning solution used to clean the manufacturing equipment. The content of metal components contained in the used cleaning solution is preferably 100 parts per trillion (ppt) by mass or less, more preferably 10 ppt by mass or less, and even more preferably 1 ppt by mass or less. There is no particular lower limit, and 0 ppt by mass or more is preferred.

[0339] A conductive compound may be added to an organic processing liquid such as a rinse solution to prevent breakdown of the chemical solution piping and various parts (filters, O-rings, tubes, etc.) due to static charging and subsequent electrostatic discharge. The conductive compound is not particularly limited, but examples include methanol. The amount added is not particularly limited, but in order to maintain favorable development or rinsing characteristics, it is preferably 10% by mass or less, more preferably 5% by mass or less. There is no particular lower limit, but 0.01% by mass or more is preferred. For the chemical solution piping, for example, stainless steel (SUS), or various piping coated with antistatically treated polyethylene, polypropylene, or fluororesin (such as polytetrafluoroethylene or perfluoroalkoxy resin), can be used. Similarly, for the filters and O-rings, antistatically treated polyethylene, polypropylene, or fluororesin (such as polytetrafluoroethylene or perfluoroalkoxy resin), can be used.

[0340] In the pattern formation method, it is preferable to generate a first active species in the resist film by irradiation with a first actinic ray or radiation, change the structure of a cation (CT) by the first active species, and generate a second active species from the structurally changed cation (also referred to as "cation (CTA)") by irradiation with a second actinic ray or radiation. The first active species is preferably an acid (the conjugate acid of the anion of the repeating unit (u1)), more preferably a sulfonic acid. The cation (CTA) obtained by changing the structure of the cation (CT) by the first active species (preferably an acid) is preferably a ketone compound. The cation (CTA) preferably has a peak area in its absorption spectrum for light with a wavelength of 300 nm to 450 nm that is larger than the peak area in the absorption spectrum of the cation (CT) for light with a wavelength of 300 nm to 450 nm. The second active species generated from the cation (CTA) by irradiation with a second actinic ray or radiation is preferably an acid.

[0341] <Method for manufacturing an electronic device> The present invention also relates to a method for manufacturing an electronic device, including the above-mentioned pattern formation method, and an electronic device manufactured by this manufacturing method. A preferred embodiment of the electronic device of the present invention is one that is installed in electrical and electronic equipment (such as home appliances, office automation (OA), media-related equipment, optical equipment, and communication equipment).

[0342] The present invention will be described in more detail below with reference to the following examples. The materials, amounts used, ratios, treatment details, and treatment procedures shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

[0343] The various components used in the resist compositions of the examples and comparative examples are shown below.

[0344] <Resins> The resins (P-1 to P-79) shown in Tables 1 to 3 below were synthesized by known methods. Note that P-1 to P-46 and P-48 to P-78 correspond to resin (X), while P-47 and P-79 do not correspond to resin (X). Tables 1 to 3 show the type and content of repeating units contained in P-1 to P-79. The content of each repeating unit is the mass ratio (mass%) of each repeating unit to all repeating units. The type of each repeating unit is indicated by the type of monomer corresponding to each repeating unit. Tables 1 to 3 also show the weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity index (PDI) of each resin. Mw, Mn, and PDI were measured by GPC (carrier: tetrahydrofuran (THF)) (polystyrene equivalent amounts). The content of each repeating unit in the resin is １３ Measurement was performed by C-NMR (Nuclear Magnetic Resonance). ｕｎｉｔ " represents the number of types of repeating units in the resin. ＰＵ " represents the content (mass %) of the photoacid-generating repeating unit in the resin.

[0345]

[0346]

[0347]

[0348] The structural formulae of M-1 to M-3 and M-36 to M-38 are shown below.

[0349]

[0350] M-4 to M-35 and M-39 are monomers containing a "cation" of any of Cation-1 to Cation-12 described above as specific examples of cations (CT) or the following Cation-13 which is not a cation (CT), and a "structure other than a cation" of any of Anion-1 to Anion-10 described above as specific examples of structures other than cations of the repeating unit (u1) or the following Anion-11 which is not a structure other than a cation of the repeating unit (u1), in the combinations shown in Table 4 below.

[0351]

[0352]

[0353] <Acid Diffusion Controller> Q-1 to Q-13 were used as the acid diffusion controller. Q-1 to Q-13 are compounds containing a "cation" of any of Cation-1 to Cation-12 described above as specific examples of the cation (CT) in the resin (X) or Cation-13 above that is not a cation (CT), and a structure containing an anion represented by Anion-12 below, in the combinations shown in Table 5 below.

[0354]

[0355]

[0356] <Solvent> As the solvent, MSL-1 to MSL-6, which are mixtures of at least two selected from the following SL-1, SL-2, SL-4, SL-5, and SL-6 in the ratios shown in Table 6 below, or the following SL-3 were used. The values ​​in Table 6 below are the mass ratios (mass%) of SL-1, SL-2, SL-4, SL-5, and SL-6 contained in MSL-1 to MSL-6. SL-1: Propylene glycol monomethyl ether acetate (PGMEA) SL-2: Propylene glycol monomethyl ether (PGME) SL-3: Cyclohexanone SL-4: γ-butyrolactone SL-5: Ethyl lactate SL-6: Diacetone alcohol

[0357]

[0358] <Developer and Rinse> The developer and rinse used were D-1, D-2, D-3, or D-5 below, or MD-1 to MD-3, which were prepared by mixing two selected from D-3 to D-5 in the proportions shown in Table 7 below. The values ​​in Table 7 below are the mass ratios (mass %) of D-3 to D-5 contained in MD-1 to MD-3. D-1: 2.38 mass % aqueous tetramethylammonium hydroxide solution D-2: Pure water D-3: Butyl acetate D-4: n-undecane D-5: 2-heptanone

[0359]

[0360] Examples 1 to 49, Comparative Examples 1 to 3 Preparation of Resist Compositions The resins shown in Tables 8 and 9 below, and, unless otherwise specified, the acid diffusion controllers, were used in amounts shown in Tables 8 and 9, and mixed with the solvents shown in Tables 8 and 9 to achieve the solids concentrations shown in Tables 8 and 9. The resulting mixtures were then filtered, in this order, first through a polyethylene filter with a pore size of 50 nm, then a nylon filter with a pore size of 10 nm, and finally a polyethylene filter with a pore size of 5 nm, to prepare resist compositions R-1 to R-49. In this resist composition, the solids refer to all components other than the solvent. In Tables 8 and 9, the content (mass %) of each component other than the solvent indicates the content (mass %) of each component relative to the total solids in the resist composition. In addition, in Tables 8 and 9, the content (mass %) of the repeating unit (u1) relative to the total amount of resins contained in each resist composition is indicated as "C ｕ１ " in Tables 8 and 9. ｕ１ " indicates the content (mass %) of the repeating unit (u1) relative to the total amount of resin contained in each resist composition. Furthermore, Tables 8 and 9 also show the content (mass %) of the photoacid-generating repeating unit relative to the total amount of resin contained in each resist composition ("C ＰＡＧ " and the unit is "mmol / g"); the content of repeating units having an acid group relative to the total amount of resin contained in each resist composition (in the table, "C ＡＣ " and the unit is "mmol / g"), and the content of repeating units having an acid-decomposable group relative to the total amount of resin contained in each resist composition (in the table, "C ＤＣ " and the unit is "mmol / g").

[0361]

[0362]

[0363] <Pattern Formation by EUV Exposure> An underlayer film-forming composition AL412 (manufactured by Brewer Science) was applied to a silicon wafer with a diameter of 300 mm and baked at 205°C for 60 seconds to form an underlayer film with a thickness of 20 nm. The resist compositions shown in Tables 10 and 11 below were applied to the underlayer film, and a pre-exposure bake (Post Applied Bake; PAB) was performed at 120°C to form a resist film with a thickness of 70 nm. This resulted in a silicon wafer with a resist film. The silicon wafer with the resist film obtained by the above procedure was subjected to pattern irradiation while varying the exposure dose using an EUV scanner NXE3400 (NA 0.33) manufactured by ASML. A hexagonal array contact hole mask (dark field mask) with a pitch of 36 nm and an opening size of 20 nm was used as the reticle. Thereafter, a post-exposure bake (PEB) was performed under the conditions shown in Tables 10 and 11, unless otherwise specified (PEB before flood exposure is also referred to as "PEB1"). The wafer was then flood-exposed (full-surface exposure) using a UV exposure device (light with a wavelength of 355 nm to 410 nm) at the exposure dose shown in Tables 10 and 11, and, unless otherwise specified, PEB was performed under the conditions shown in Tables 10 and 11 (PEB after flood exposure is also referred to as "PEB2"). The wafer was then developed for 30 seconds using the developer shown in Tables 10 and 11, and, unless otherwise specified, rinsed by pouring the rinse solution shown in Tables 10 and 11 over the wafer while rotating it at 1000 rpm for 10 seconds. Then, the wafer was rotated at 4000 rpm for 30 seconds, thereby obtaining a positive-tone contact hole pattern with a pitch of 36 nm.

[0364] <Evaluation (Sensitivity, LCDU, and Resolution)> When the above mask was used, the exposure amount at which a hole CD (Critical Dimension) of 18 nm was resolved on average was defined as the sensitivity (unit: mJ / cm ２) The smaller the sensitivity value, the better the sensitivity. Using a length-measuring scanning electron microscope (SEM: Scanning Electron Microscope (CG6300, manufactured by Hitachi High-Technologies Corporation)), 2000 random holes at each exposure dose were observed, and the standard deviation (σ) of the hole CD was calculated. The variation in hole CD was evaluated using 3σ, and the value of 3σ was taken as LCDU (unit: nm). The smaller the LCDU value, the better the LCDU. Furthermore, using a length-measuring scanning electron microscope (CG6300, manufactured by Hitachi High-Technologies Corporation), 2000 random holes at each exposure dose were observed, and the average hole diameter and hole quality were evaluated. The minimum value of the average hole diameter (CD) at an exposure dose that satisfied the condition that no non-resolved holes occurred among the 2000 observed holes was calculated. ｍｉｎ ) and the maximum average hole diameter (CD) at an exposure dose that satisfies the condition that no non-resolved holes occur among the 2000 holes observed. ｍａｘ ) and CD ｍａｘ and CDs ｍｉｎ The difference between these values ​​was taken and defined as the Failure Free Latitude (FFL). The larger this value, the better the resolution and the better the performance (resolution), so this value was used as an index of resolution. The results are shown in Tables 10 and 11 below. The unit of "sensitivity" in Tables 10 and 11 is "mJ / cm ２ ", the unit of "LCDU" is "nm", and the unit of "resolution (FFL)" is "nm".

[0365]

[0366]

[0367] <Integrated absorbance values ​​before and after exposure and calculation method> For Cation-1 to Cation-12, the peak areas of the absorption spectra for light with wavelengths of 300 nm to 450 nm before and after the structure was changed by the action of acid were determined using Gaussian 16 as the electronic state calculation software provided by Gaussian, by TD-DFT calculation using B3LYP / 6-31+G(d) and acetonitrile solvent conditions using the IEFPCM method, and by UV-Vis spectrum calculation using the calculation software GaussView under conditions of a half-width of 0.2 eV and an output wavelength interval of 1 nm. The results are shown in Table 12 below.

[0368]

[0369] Examples 50 to 88, Comparative Examples 4 to 6 <Preparation of Resist Compositions> Resist compositions were prepared in the same manner as in Example 1, etc., except that the resins and acid diffusion controllers shown in Tables 13 and 14 below were mixed with the solvents shown in Tables 13 and 14 to achieve the solids concentrations shown in Tables 13 and 14.

[0370]

[0371]

[0372] <Pattern Formation by EUV Exposure> An underlayer film-forming composition AL412 (manufactured by Brewer Science) was applied to a silicon wafer with a diameter of 300 mm and baked at 205°C for 60 seconds to form an underlayer film with a thickness of 20 nm. The resist compositions shown in Tables 15 and 16 below were applied to the underlayer film, and a pre-exposure bake (Post Applied Bake; PAB) was performed at 120°C to form a resist film with a thickness of 35 nm. This resulted in a silicon wafer with a resist film. The silicon wafer with the resist film obtained by the above procedure was subjected to pattern irradiation while varying the exposure dose using an EUV scanner NXE3400 (NA 0.33) manufactured by ASML. A hexagonal array contact hole mask (dark field mask) with a pitch of 36 nm and an opening size of 20 nm was used as the reticle. The sensitivity was determined by the exposure dose such that the pillar CD (Critical Dimension) was resolved to an average of 18 nm when using the above mask. Then, post-exposure bake (PEB) was performed under the conditions shown in Tables 15 and 16, unless otherwise specified (PEB before flood exposure is also referred to as "PEB1"). The wafer was then flood-exposed (full surface exposed) using a UV exposure device (light with a wavelength of 355 nm to 410 nm) at the exposure dose shown in Tables 15 and 16, and PEB was performed under the conditions shown in Tables 15 and 16, unless otherwise specified (PEB after flood exposure is also referred to as "PEB2"). Next, the wafer was developed for 30 seconds using the developer shown in Tables 15 and 16, and, unless otherwise specified, the wafer was rinsed by pouring the rinse solution shown in Tables 15 and 16 over the wafer for 10 seconds while rotating the wafer at a rotation speed of 1000 rpm, and then the wafer was rotated at a rotation speed of 4000 rpm for 30 seconds to obtain a negative pillar pattern with a pitch of 36 nm.

[0373] <Evaluation (Sensitivity, LCDU, and Resolution)> Sensitivity, LCDU, and resolution were evaluated in the same manner as in Example 1. The results are shown in Tables 15 and 16 below. The unit of "Sensitivity" in Tables 15 and 16 is "mJ / cm ２ ", the unit of "LCDU" is "nm", and the unit of "resolution (FFL)" is "nm".

[0374]

[0375]

[0376] Examples 89 to 129, Comparative Examples 7 to 9 <Preparation of Resist Compositions> Resist compositions were prepared in the same manner as in Example 1, etc., except that the resins and acid diffusion controllers shown in Tables 17 and 18 below were mixed with the solvents shown in Tables 17 and 18 so as to achieve the solids concentrations shown in Tables 17 and 18.

[0377]

[0378]

[0379] <Pattern Formation by EUV Exposure> An underlayer film-forming composition AL412 (manufactured by Brewer Science) was applied to a silicon wafer with a diameter of 300 mm and baked at 205°C for 60 seconds to form an underlayer film with a thickness of 20 nm. The resist compositions shown in Tables 19 and 20 below were applied to the underlayer film, and a pre-exposure bake (Post Applied Bake; PAB) was performed at 120°C to form a resist film with a thickness of 70 nm. This resulted in a silicon wafer with a resist film. The silicon wafer with the resist film obtained by the above procedure was subjected to pattern irradiation while varying the exposure dose using an EUV scanner NXE3400 (NA 0.33) manufactured by ASML. A hexagonal array contact hole mask (bright field mask) with a pitch of 36 nm and an opening size of 20 nm was used as the reticle. The sensitivity was determined by the exposure dose that resolved an average hole CD (Critical Dimension) of 18 nm when using the above mask. Then, post-exposure bake (PEB) was performed under the conditions shown in Tables 19 and 20, unless otherwise specified (PEB before flood exposure is also referred to as "PEB1"). The wafer was then flood-exposed (full surface exposed) using a UV exposure device (light with a wavelength of 355 nm to 410 nm) at the exposure dose shown in Tables 19 and 20, and PEB was performed under the conditions shown in Tables 19 and 20, unless otherwise specified (PEB after flood exposure is also referred to as "PEB2"). Next, the wafer was developed for 30 seconds using the developer shown in Table 19 or Table 20, and, unless otherwise specified, rinsed by pouring the rinse solution shown in Table 19 or Table 20 over the wafer for 10 seconds while rotating the wafer at 1000 rpm, and then rotating the wafer at 4000 rpm for 30 seconds, thereby obtaining a negative contact hole pattern with a pitch of 36 nm.

[0380] <Evaluation (Sensitivity, LCDU, and Resolution)> Evaluation of LCDU and FFL was carried out in the same manner as in Example 1. The results are shown in Tables 19 and 20 below. The unit of "Sensitivity" in Tables 19 and 20 is "mJ / cm ２ ", the unit of "LCDU" is "nm", and the unit of "resolution (FFL)" is "nm".

[0381]

[0382]

[0383] From the above results, it was found that the resist compositions used in the examples were excellent in sensitivity, LCDU and resolution.

[0384] The present invention provides an actinic ray-sensitive or radiation-sensitive resin composition having excellent sensitivity, LCDU, and resolution. The present invention also provides a resist film, a pattern forming method, and a method for manufacturing an electronic device, which use the actinic ray-sensitive or radiation-sensitive resin composition.

[0385] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2023-170175) filed on September 29, 2023, the contents of which are incorporated herein by reference.

Claims

1. An actinic ray-sensitive or radiation-sensitive resin composition comprising a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) comprises at least one cation selected from the group consisting of cations represented by the following formula (CT-1) and cations represented by the following formula (CT-2), and an anion bonded to a molecular chain of the resin (X), and the content of the repeating unit (u1) is 40 mass% or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition. In formula (CT-1) and formula (CT-2), R ３ and R ４ R each independently represents an organic group, a hydroxy group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom. ３ When there are multiple R ３ R may be bonded directly to each other via a single bond or via a linking group to form a ring. ４ When there are multiple R ４ R may be bonded directly to each other via a single bond or via a linking group to form a ring. ５ and R ６ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ５ and R ６ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. ５ and R ６ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. ７ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. ８ and R ９ each independently represents a hydrogen atom, an organic group, a hydroxyl group, a mercapto group, an amino group, a nitro group, a phosphino group, a silyl group, or a halogen atom, or R ８ and R ９ R is bonded to represent a single bond or a divalent linking group. １０ and R １１ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １０ and R １１ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １０ and R １１ may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group to form a ring. １ , Y ２ , Y ３ and Y ４ Each independently represents an oxygen atom or a sulfur atom. １ represents an alkylene group, a cycloalkylene group, an alkenylene group, a cycloalkenylene group, an arylene group, a heteroarylene group, or a linking group formed by bonding at least two groups selected from the group consisting of an alkylene group, a cycloalkylene group, an alkenylene group, a cycloalkenylene group, an arylene group, and a heteroarylene group via at least one group selected from the group consisting of a single bond, an oxygen atom, a sulfur atom, and a nitrogen atom-containing group, or a single bond. ２ and L ３ each independently represents a single bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, a carbonyl group, a sulfinyl group, or a sulfonyl group. a and b each independently represent an integer of 1 to 3. When a represents 1, c represents an integer of 0 to 3. When a represents 2, c represents an integer of 0 to 5. When a represents 3, c represents an integer of 0 to 7. When b represents 1, d represents an integer of 0 to 4. However, d+f is an integer of 0 to 4. When b represents 2, d represents an integer of 0 to 6. However, d+f is an integer of 0 to 6. When b represents 3, d represents an integer of 0 to 8. However, d+f is an integer of 0 to 8. e represents 0 or 1. f represents an integer of 0 to 4. However, e+f is an integer of 1 to 4. In formula (CT-1), R １ and R ２ R each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, or a heteroaryl group. １ and R ２ When R contains methylene groups, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group. １ , R ２ and L １ At least two of the aromatic rings to which R is bonded may be bonded directly via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring. １２ represents an aryl group or a heteroaryl group. １２ and L １ may be bonded directly to the aromatic ring via a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, and a methylene group to form a ring.

2. An actinic ray-sensitive or radiation-sensitive resin composition containing a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one type of cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change due to the action of an acid, and the structure after the structural change has a larger peak area in an absorption spectrum for light having a wavelength of 300 nm to 450 nm than the peak area in an absorption spectrum for light having a wavelength of 300 nm to 450 nm for the structure before the structural change, and the content of the repeating unit (u1) is 40 mass% or more based on the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

3. An actinic ray-sensitive or radiation-sensitive resin composition comprising a resin (X) having a repeating unit (u1) and a solvent, wherein the repeating unit (u1) contains at least one type of cation and an anion bonded to a molecular chain of the resin (X), the cation undergoes a structural change under the action of an acid to produce a ketone group, and the content of the repeating unit (u1) is 40 mass% or more relative to the total amount of resins contained in the actinic ray-sensitive or radiation-sensitive resin composition.

4. The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, wherein the repeating unit (u1) is a repeating unit that generates an acid upon exposure to actinic rays or radiation.

5. The actinic ray-sensitive or radiation-sensitive resin composition according to claim 1, which satisfies at least one of the following conditions (i) and (ii): Condition (i): The actinic ray-sensitive or radiation-sensitive resin composition contains an acid diffusion controller which is a compound different from the resin (X); and Condition (ii): The resin (X) has a repeating unit having an acid diffusion control ability.

6. An actinic ray-sensitive or radiation-sensitive resin composition as described in claim 1, wherein the content of the repeating unit (u1) is 60 mass% or more based on the total amount of resin contained in the actinic ray-sensitive or radiation-sensitive resin composition.

7. An actinic ray-sensitive or radiation-sensitive resin composition as described in claim 1, wherein the content of the repeating unit (u1) is 80 mass% or more based on the total amount of resin contained in the actinic ray-sensitive or radiation-sensitive resin composition.

8. A resist film formed using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 7.

9. A pattern formation method comprising the steps of: forming a resist film on a substrate using the actinic ray-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 7; irradiating the resist film with a first actinic ray or radiation; irradiating the resist film after the irradiation with the first actinic ray or radiation with a second actinic ray or radiation; and developing the resist film after the irradiation with the second actinic ray or radiation using a developer.

10. The pattern formation method according to claim 9, wherein the wavelength of the first actinic ray or radiation is shorter than the wavelength of the second actinic ray or radiation.

11. The pattern forming method according to claim 10, wherein the first actinic ray or radiation is an electron beam or extreme ultraviolet ray.

12. The pattern formation method according to claim 9, wherein a first active species is generated in the resist film by irradiation with the first actinic ray or radiation, the structure of the cation is changed by the first active species, and a second active species is generated from the cation whose structure has been changed by irradiation with the second actinic ray or radiation.

13. The pattern forming method according to claim 9, wherein the developer is an alkaline aqueous solution.

14. The pattern forming method according to claim 9, wherein the developer is an organic solvent.

15. A method for manufacturing an electronic device, comprising the pattern formation method according to claim 9.

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