Resist composition and pattern forming method

Abstract

To provide novel resist compositions and pattern forming methods.SOLUTION: The present invention provides a resist composition containing (A) a resin component that shows solubility changes in the developer in response to acid action, and (B) a polyacid salt.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a resist composition and a pattern forming method. [Background technology]

[0002] A microfabrication technology called lithography is used to form the fine circuits of semiconductor elements. Lithography is a technology in which a circuit pattern drawn on an original mask is transferred to the resist on a substrate via an exposure device.

[0003] Resists used in the above-mentioned lithography are required to have properties such as good sensitivity to the exposure light source of the exposure device and good resolution for reproducing fine dimensional patterns. However, it has been pointed out that improving the sensitivity of a resist to an exposure light source results in a degradation of resolution, i.e., a trade-off between sensitivity and resolution, and it has been difficult to maintain a balance between the two in a resist. For this reason, research and development of new resist compositions suited to different types of exposure light sources is underway.

[0004] For example, Patent Document 1 discloses an invention relating to a radiation-sensitive composition having excellent sensitivity and resolution, the radiation-sensitive composition containing a polymetalloxane having a specific structural unit (germanium atom, tin atom, or lead atom), a radiation-sensitive acid generator, and a solvent. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Pat. No. 1,506,976 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a novel resist composition and a pattern forming method. [Means for solving the problem]

[0007] Means for Solving the Problems The present inventors conducted intensive research in order to solve the above-mentioned problems, and as a result, discovered that in a resist composition that contains (A) a resin component whose solubility in a developer changes under the action of acid, and (B) a polyacid salt, the strong acidity and solubility in a developer in the exposed area of ​​the resist composition can be adjusted by modifying the structure of the anion and / or cation moieties of component (B), and thus completed the present invention.

[0008] That is, the present invention relates to the following inventions. [1] A resist composition comprising: (A) a resin component whose solubility in a developer changes under the action of an acid; and (B) a polyacid salt. [2] The resist composition according to [1], wherein the anion moiety of the polyacid salt (B) is a polyoxomolybdate anion, a polyoxotungstate anion, a polyoxoniobate anion, or a polyoxotantalate anion. [3] The resist composition according to [1], wherein the cation moiety of the polyacid salt (B) is an organic sulfonium cation, an organic iodonium cation, or an organic quaternary ammonium cation. [4] The resist composition according to [1], wherein the (B) polyacid salt is a salt of a polyoxomolybdate anion, a polyoxotungstate anion, a polyoxoniobate anion, or a polyoxotantalate anion with an organic sulfonium cation, an organic iodonium cation, or an organic quaternary ammonium cation. [5] The resist composition according to [1], further comprising (C) an acid generator or an acid diffusion controller. [6] A step of applying the resist composition according to any one of [1] to [5] above onto a substrate to form a resist film; exposing the resist film to light; developing the exposed resist film with a developer; The pattern forming method comprises the steps of: Effect of the Invention

[0009] According to the present invention, it is possible to provide a novel resist composition and a method for forming a pattern. In addition, since the resist composition according to the present invention contains a polyacid salt as component (B) that is capable of highly absorbing light from a light source such as DUV, XUV, EUV, or an electron beam, it can be suitably used as a resist composition that is compatible with these exposure light sources. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Preferred embodiments of the present invention will be described in detail below, however, the present invention is not limited to the following embodiments.

[0011] [1. Resist composition] The resist composition according to this embodiment contains (A) a resin component whose solubility in a developer changes under the action of an acid, and (B) a polyacid salt. Another resist composition according to this embodiment may further contain (C) an acid generator or an acid diffusion controller in addition to the components (A) and (B).

[0012] The meanings of terms, symbols, etc. used in this specification will be explained below, and an embodiment of the present invention will be described in more detail.

[0013] In this specification, the term "halogen atom" refers to a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0014] In the present specification, for example, "C 1-6 " and other terms refer to the number of carbon atoms in the core group.

[0015] In this specification, "C 1-18The term "hydrocarbylene group" refers to a divalent hydrocarbon group generated by removing two hydrogen atoms from a hydrocarbon having 1 to 18 carbon atoms. The hydrocarbylene group may be linear or branched, or may be partially or entirely cyclic. The hydrocarbylene group includes alkylene groups, arylene groups, and the like. Also, "C 1-18 A divalent carbon atom at any position of the "hydrocarbylene group" may be replaced by -O-, -S-, -C(=O)-, -COO-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, -SO-, or -SO2- (however, adjacent divalent carbon atoms are not replaced at the same time). "C 1-18 The "hydrocarbylene group" is not particularly limited, and examples thereof include a "C group" such as a methylene group, an ethylene group, an n-propylene group, an i-propylene group, a cyclopentadiyl group, a cyclohexanediyl group, an oxyethane-1,1-diyl group, an oxyethane-1,2-diyl group, an oxypropane-1,3-diyl group, an oxypropane-1,2-diyl group, a 2-methylpropane-1,3-diyl group, or an oxyethyleneoxyethane-1,1-diyl group. 1-18 Alkylene groups such as 1,4-phenylene groups, 1,3-phenylene groups, 1,2-phenylene groups, 1,4-naphthylene groups, 1,5-naphthylene groups, 1,8-naphthylene groups, 4,4'-biphenylene groups, anthracenediyl groups, phenanthrenediyl groups, naphthacenediyl groups, pyrenediyl groups, perylenediyl groups, and chrysenediyl groups. 6-18 An arylene group" is an example.

[0016] In this specification, "C 1-18 The term "alkyl group" refers to a linear or branched alkyl group having 1 to 18 carbon atoms. Also, "C 1-18 Any divalent carbon atom at any position except the terminal end contained in the "alkyl group" may be replaced with -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2-. However, adjacent divalent carbon atoms may not be replaced at the same time. "C 1-18 The "alkyl group" is not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an i-pentyl group, a sec-pentyl group, a t-pentyl group, a neopentyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, an n-hexyl group, an i-hexyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 1 Examples of the alkyl group include 1-dimethylbutyl group, 1,2-dimethylbutyl group, 2,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,1,2-trimethylpropyl group, 1,2,2-trimethylpropyl group, 1-ethyl-1-methylpropyl group, 1-ethyl-2-methylpropyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, and n-dodecyl group. "C 1-18 Examples of the "alkyl group" in which a divalent carbon atom at any position excluding the terminal is replaced with -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO- include, but are not limited to, a 2-methoxyethoxymethyl group, an ethoxycarbonylmethyl group, and the like.

[0017] In this specification, "C 1-18 Haloalkyl group means "C 1-18 The term "alkyl group" refers to a group in which one or more hydrogen atoms of the "alkyl group" have been substituted with halogen atoms. "C 1-18 The "haloalkyl group" is not particularly limited, and examples thereof include a dichloromethyl group, a trifluoromethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a pentafluoroethyl group, and a 3,3,3-trifluoropropyl group.

[0018] In this specification, "C 2-18 An alkenyl group is a group having two or more carbon atoms.1-18 "Alkyl group" means an alkenyl group having one or more double bonds, and includes alkadienyl groups, alkatrienyl groups, etc. "C 2-18 The "alkenyl group" is not particularly limited, and examples thereof include a vinyl group (ethenyl group), an allyl group (2-propenyl group), a 1-propenyl group, an isopropenyl group (1-methylvinyl group), a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, and a dodecenyl group.

[0019] In this specification, "C 2-18 An alkynyl group is a group with two or more carbon atoms. 1-18 "Alkyl group" means an alkynyl group having one or more triple bonds. "C 2-18 The "alkynyl group" is not particularly limited, and examples thereof include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a pentynyl group, a hexynyl group, a heptynyl group, an octynyl group, a nonynyl group, a decynyl group, an undecynyl group, and a dodecynyl group.

[0020] In this specification, "C 3-18 The term "alicyclic group" refers to a hydrocarbon group having, in whole or in part, a monocyclic or polycyclic structure having 3 to 18 carbon atoms. Alicyclic groups also include cycloalkyl groups, cycloalkenyl groups, cycloalkynyl groups, monocycloalkyl groups, polycycloalkyl groups, and the like. Also, "C 3-18 A divalent carbon atom at any position except for the terminal position contained in the "alicyclic group" may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or SO2- (however, adjacent divalent carbon atoms are not replaced at the same time). "C 3-18The "cycloalkyl group" is not particularly limited, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a 1-i-propylcyclopentan-1-yl group, a cyclohexyl group, a t-butylcyclohexyl group, a tricyclodecanyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, a 2-methyladamantan-2-yl group, a 2-i-propyladamantan-2-yl group, a bornyl group, a norbornyl group, a fenchyl group, a pinanyl group, an adamantyl group, a tricyclodecyl group, a tetracyclododecyl group, a cyclopropylmethyl group, a cyclobutylmethyl group, a cyclopentylmethyl group, a cyclohexylmethyl group, a bornylmethyl group, a norbornylmethyl group, an adamantylmethyl group, a 1-methylcyclopentyloxycarbonylmethyl group, a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group.

[0021] As used herein, the term "3- to 18-membered non-aromatic heterocyclic group" refers to a 3- to 18-membered non-aromatic heterocyclic group containing one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, and may be a monocyclic, polycyclic, or condensed ring, and may be saturated or partially unsaturated. The "3- to 18-membered non-aromatic heterocyclic group" is not particularly limited, and examples thereof include an aziridinyl group, an azetidyl group, a pyrrolidinyl group, a pyrrolyl group, a piperidinyl group, a piperazinyl group, a morpholinyl group, a thiomorpholinyl group, a tetrahydrofuryl group, a tetrahydropyranyl group, an oxetanyl group, a tetrahydrofuryl group, a tetrahydropyranyl group, an imidazolinyl group, an oxazolinyl group, a 2,5-diazabicyclo[2.2.1]heptyl group, a 2,5-diazabicyclo[2.2.2]octyl group, a 3,8-diazabicyclo[3.2.1]octyl group, a 1,4-diazabicyclo[4.3.0]nonyl group, a 1-azaadamantyl group, and a 2-azaadamantyl group.

[0022] In this specification, "C 2-18The term "aryl group" means an aromatic hydrocarbon cyclic group having 6 to 18 carbon atoms or an aromatic heterocyclic group having 2 to 10 carbon atoms. In the case of an aromatic heterocyclic group, a ring is formed by a carbon atom having 2 to 10 carbon atoms and one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom, and an oxygen atom, and each of these may be a monocyclic ring, a polycyclic ring, or a condensed ring. "C 2-18 The "aryl group" is not particularly limited, and examples thereof include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, an azulenyl group, a pentalenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a phenanthrenyl group, and an anthracenyl group.

[0023] In this specification, "C 7-18 Aralkyl groups are defined as groups consisting of C 1-12 The substitutable portion of the "alkyl group" is the above "C 2-12 The term "aryl group" refers to a group substituted with an "aryl group." "C 7-18 The "aralkyl group" is not particularly limited, and examples thereof include a benzyl group, a phenethyl group, a 3-phenylpropyl group, a 4-phenylbutyl group, a 1-naphthylmethyl group, and a 2-naphthylmethyl group.

[0024] In this specification, "C 1-18 The term "hydrocarbyl group" refers to a monovalent group generated by removing one hydrogen atom from a hydrocarbon having 1 to 18 carbon atoms. Examples of hydrocarbyl groups include alkyl groups, alkenyl groups, alkynyl groups, alicyclic groups, aryl groups, and aralkyl groups. Also, "C 1-18 Any divalent carbon atom at any position except the terminal contained in the "hydrocarbyl group" may be replaced with -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2- (however, adjacent divalent carbon atoms may not be replaced at the same time). This point is explained in the following section "C 1-18 "C" used in the explanation of the definition of "hydrocarbyloxy group" etc. 1-18 The same applies to "hydrocarbyl group" and the like. "C 1-18 The "hydrocarbyl group" is not particularly limited, and examples thereof include "C 1-18 Alkyl group," "C 2-18 alkenyl group," "C 2-18 Alkynyl group, C 3-18 Alicyclic group”, “C 2-18 Aryl group, C 7-18 aralkyl group".

[0025] In this specification, "C 1-18 "Hydrocarbyloxy group" means "C 1-18 The term "hydrocarbyl group" refers to a group having an oxygen atom (-O-) bonded to a "hydrocarbyl group." "C 1-18 The "hydrocarbyloxy group" is not particularly limited, and examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, an i-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentoxy group, an i-pentoxy group, a sec-pentoxy group, an n-hexoxy group, an i-hexoxy group, a 1,1-dimethylpropyloxy group, a 1,2-dimethylpropyloxy group, a 2,2-dimethylpropyloxy group, a 1-methyl-2-ethylpropyloxy group, a 1-ethyl-2-methylpropyloxy group, a 1,1,2-trimethylpropyloxy group, a 1,2,2-trimethylpropyloxy group, a 1,1-dimethylbutyloxy group, a 1,2-dimethylbutyloxy group, a 2,2-dimethylbutyloxy group, a 2,3-dimethylbutyloxy group, a 1,3-dimethylbutyloxy group, a 2-ethylbutyloxy group, a 2-methylpentyloxy group, and a 3-methylpentyloxy group. 1-18 Alkoxy group; cyclopropyloxy group, cyclobutyloxy group, cyclopentyloxy group, cyclohexyloxy group, cycloheptyloxy group, cyclooctyloxy group, 1-methylcyclopentyloxycarbonylmethoxy group, 1-ethylcyclohexyloxycarbonylmethoxy group, 1-methyladamantyloxycarbonylmethoxy group, etc. 3-18Alicyclic oxy group; phenyloxy group, 1-naphthyloxy group, 2-naphthyloxy group, azulenyloxy group, pentalenyloxy group, heptalenyloxy group, indacenyloxy group, acenaphthyloxy group, phenanthrenyloxy group, anthracenyloxy group, etc. 6-18 aryloxy group" and the like. "C 1-18 The hydrocarbyloxy group includes "C 1-18 It is preferable that a divalent carbon atom at any position except the terminal contained in the "hydrocarbyl group" is replaced with -O-, -C(=O)-, and / or -C(=O)O-. 1-18 A "hydrocarbyloxycarbonylalkyloxy group" is more preferred, and from the viewpoint of solubility, it is even more preferred that the carbon bonded to the oxygen atom of the hydrocarbyloxy is a tertiary carbon. Specific examples of the hydrocarbyloxy include optionally substituted ethylcyclopentyloxy, methyladamantyloxy, ethyladamantyloxy, t-butyloxy, and the like.

[0026] In this specification, "C 1-18 The term "hydrocarbyl carbonyl group" means "C 1-18 The term "hydrocarbyl group" refers to a group having a carbonyl group (-C(=O)-) bonded to a "hydrocarbyl group." "C 1-18 The hydrocarbyl carbonyl group is not particularly limited, and examples thereof include acetyl, propionyl, isopropionyl, butyryl, isobutyryl, valeryl, isovaleryl, pentanoyl, 3-methylbutanoyl, pivaloyl, hexanoyl, and heptanoyl groups. 1-18 Alkylcarbonyl group; cyclopropylcarbonyl group, cyclobutylcarbonyl group, cyclopentylcarbonyl group, 2-methylcyclopentylcarbonyl group, 3-methylcyclopentylcarbonyl group, cyclohexylcarbonyl group, 2-methylcyclohexylcarbonyl group, 3-methylcyclohexylcarbonyl group, 4-methylcyclohexylcarbonyl group, adamantylcarbonyl group, and other C 3-18Alicyclic carbonyl group; Benzoyl group, 1-naphthoyl group, 2-naphthoyl group, etc. 6-18 arylcarbonyl group" and the like.

[0027] In this specification, "C 1-18 The term "hydrocarbyl carbonyloxy group" means "C 1-18 The term "hydrocarbyl carbonyl group" refers to a group in which an oxygen atom (-O-) is bonded to a "hydrocarbyl carbonyl group." "C 1-18 The "hydrocarbylcarbonyloxy group" is not particularly limited, and examples thereof include a "C methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an isopropylcarbonyloxy group, an n-butylcarbonyloxy group, an isobutylcarbonyloxy group, a t-butylcarbonyloxy group, an n-pentylcarbonyloxy group, an isopentylcarbonyloxy group, a hexylcarbonyloxy group, and the like. 1-18 Alkylcarbonyloxy group; cyclopropylcarbonyloxy group, cyclobutylcarbonyloxy group, cyclopentylcarbonyloxy group, cyclohexylcarbonyloxy group, etc. 3-18 Alicyclic carbonyloxy group; phenylcarbonyloxy group, naphthylcarbonyloxy group, acenaphthylcarbonyloxy group, phenanthrenylcarbonyloxy group, anthracenylcarbonyloxy group, etc. 6-18 arylcarbonyloxy group" and the like.

[0028] In this specification, "C 1-18 The hydrocarbyloxycarbonyl group is defined as "C 1-18 The term "hydrocarbyloxy group" refers to a group in which a carbonyl group (-C(=O)-) is bonded to a "hydrocarbyloxy group." "C 1-18 The "hydrocarbyloxycarbonyl group" is not particularly limited, and examples thereof include "C methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, i-propoxycarbonyl group, n-butoxycarbonyl group, i-butoxycarbonyl group, sec-butoxycarbonyl group, t-butoxycarbonyl group, n-pentoxycarbonyl group, neopentyloxycarbonyl group, etc.1-18 alkoxycarbonyl group; cyclopropyloxycarbonyl group, cyclobutyloxycarbonyl group, cyclopentyloxycarbonyl group, cyclohexyloxycarbonyl group, 2-methylcyclopentyloxycarbonyl group, 3-methylcyclopentyloxycarbonyl group, 2-methylcyclohexyloxycarbonyl group, 3-methylcyclohexyloxycarbonyl group, 4-methylcyclohexyloxycarbonyl group, etc. 3-18 Alicyclic oxycarbonyl group; phenoxycarbonyl group, naphthoxycarbonyl group, acenaphthyloxycarbonyl group, phenanthrenyloxycarbonyl group, anthracenyloxycarbonyl group, etc. 6-18 aryloxycarbonyl group" and the like.

[0029] In this specification, "C 1-18 The term "hydrocarbyloxycarbonyloxy group" means "C 1-18 The term "hydrocarbyloxycarbonyl group" refers to a group in which an oxygen atom (-O-) is bonded to a "hydrocarbyloxycarbonyl group." "C 1-18 The "hydrocarbyloxycarbonyloxy group" is not particularly limited, and examples thereof include a "C methoxycarbonyloxy group, an ethoxycarbonyloxy group, an n-propyloxycarbonyloxy group, an i-propyloxycarbonyloxy group, an n-butoxycarbonyloxy group, an i-butoxycarbonyloxy group, a sec-butoxycarbonyloxy group, a t-butoxycarbonyloxy group, an n-pentyloxycarbonyloxy group, an i-pentyloxycarbonyloxy group, an n-hexyloxycarbonyloxy group, and the like. 1-18 alkoxycarbonyloxy group; cyclopropyloxycarbonyloxy group, cyclobutyloxycarbonyloxy group, cyclopentyloxycarbonyloxy group, cyclohexyloxycarbonyloxy group, etc. 3-18 Alicyclic oxycarbonyloxy group; phenoxycarbonyloxy group, naphthoxycarbonyloxy group, acenaphthyloxycarbonyloxy group, phenanthrenyloxycarbonyloxy group, anthracenyloxycarbonyloxy group, etc. 6-18aryloxycarbonyloxy group" and the like.

[0030] In this specification, "C 1-18 A "hydrocarbylamino group" is one "C 1-18 "Hydrocarbyl group" means a group attached to an amino group. "C 1-18 The "hydrocarbylamino group" is not particularly limited, and examples thereof include a methylamino group, an ethylamino group, an n-propylamino group, an i-propylamino group, an n-butylamino group, an i-butylamino group, a sec-butylamino group, a t-butylamino group, an n-pentylamino group, an i-pentylamino group, a neopentylamino group, an n-hexylamino group, and the like. 1-18 Alkylamino group; cyclopropylamino group, cyclobutylamino group, cyclopentylamino group, 2-methylcyclopentylamino group, 3-methylcyclopentylamino group, cyclohexylamino group, 2-methylcyclohexylamino group, 3-methylcyclohexylamino group, 4-methylcyclohexylamino group, etc. 3-18 Alicyclic amino group; phenylamino group, 1-naphthylamino group, 2-naphthylamino group, etc. 6-18 arylamino group" and the like.

[0031] As used herein, "diC 1-18 A "hydrocarbylamino group" is a group consisting of two identical or different "C 1-18 "Hydrocarbyl group" means a group attached to an amino group. "JiC 1-18The "alkylamino group" is not particularly limited, and examples thereof include a dimethylamino group, a diethylamino group, a di-n-propylamino group, a diisopropylamino group, a di-n-butylamino group, a diisobutylamino group, a di-t-butylamino group, a di-n-pentylamino group, a di-n-hexylamino group, an N-ethyl-N-methylamino group, an N-methyl-Nn-propylamino group, an N-isopropyl-N-methylamino group, an Nn-butyl-N-methylamino group, "Di-C" groups such as N-isobutyl-N-methylamino group, Nt-butyl-N-methylamino group, N-methyl-Nn-pentylamino group, Nn-hexyl-N-methylamino group, N-ethyl-Nn-propylamino group, N-ethyl-N-isopropylamino group, Nn-butyl-N-ethylamino group, N-ethyl-N-isobutylamino group, Nt-butyl-N-ethylamino group, N-ethyl-Nn-pentylamino group, and N-ethyl-Nn-hexylamino group. 1-18 Alkylamino group; dicyclopropylamino group, dicyclobutylamino group, dicyclopentylamino group, dicyclohexylamino group, etc. 3-18 Alicyclic amino group; diphenylamino group, phenylnaphthylamino group, etc. 6-18 Arylamino group; N-methylcyclopentanamino group, N-methylcyclohexylamino group, etc. 1-18 Alkyl-NC 3-18 Cycloalkylamino group; N-methyl-2-phenylethylamino group, N-ethyl-N-(4-methylphenyl)amino group, etc. 1-18 Alkyl-NC 6-18 arylamino group" and the like.

[0032] In this specification, "C 1-18 The term "hydrocarbylaminocarbonyl group" means "C 1-18 The term "hydrocarbylamino group" refers to a group in which a carbonyl group (-C(=O)-) is bonded to a "hydrocarbylamino group." "C 1-18The "hydrocarbylaminocarbonyl group" is not particularly limited, and examples thereof include a "C aminocarbonyl group" such as a methylaminocarbonyl group, an ethylaminocarbonyl group, an n-propylaminocarbonyl group, an i-propylaminocarbonyl group, an n-butylaminocarbonyl group, a sec-butylaminocarbonyl group, a t-butylaminocarbonyl group, an n-pentylaminocarbonyl group, a 2-pentylaminocarbonyl group, a neopentylaminocarbonyl group, a 4-methyl-2-pentylaminocarbonyl group, an n-hexylaminocarbonyl group, and a 3-methyl-n-pentylaminocarbonyl group. 1-18 alkylaminocarbonyl group; cyclopropylaminocarbonyl group, cyclobutylaminocarbonyl group, cyclopentylaminocarbonyl group, cyclohexylaminocarbonyl group, 2-methylcyclopentylaminocarbonyl group, 3-methylcyclopentylaminocarbonyl group, 2-methylcyclohexylaminocarbonyl group, 3-methylcyclohexylaminocarbonyl group, 4-methylcyclohexylaminocarbonyl group, etc. 3-18 Alicyclic aminocarbonyl group; phenylaminocarbonyl group, 1-naphthylaminocarbonyl group, 2-naphthylaminocarbonyl group, etc. 6-18 arylaminocarbonyl group.

[0033] As used herein, "diC 1-18 The hydrocarbyl aminocarbonyl group is a di-C 1-18 The term "hydrocarbylamino group" refers to a group in which a carbonyl group (-C(=O)-) is bonded to a "hydrocarbylamino group." "JiC 1-18The "hydrocarbylamino group" is not particularly limited, and examples thereof include a dimethylaminocarbonyl group, a diethylaminocarbonyl group, a di-n-propylaminocarbonyl group, a diisopropylaminocarbonyl group, a di-n-butylaminocarbonyl group, a diisobutylaminocarbonyl group, a di-t-butylaminocarbonyl group, a di-n-pentylaminocarbonyl group, a di-n-hexylaminocarbonyl group, an N-ethyl-N-methylaminocarbonyl group, an N-methyl-Nn-propylaminocarbonyl group, an N-isopropyl-N-methylaminocarbonyl group, an Nn-butyl-N-methylaminocarbonyl group, an N-isobutyl-N-methylaminocarbonyl group, an Nt-butyl-N-methylaminocarbonyl group, an N-methyl-Nn-pentylaminocarbonyl group, an Nn-hexyl-N-methylaminocarbonyl group, "Di-C" groups such as N-ethyl-Nn-propylaminocarbonyl group, N-ethyl-N-isopropylaminocarbonyl group, Nn-butyl-N-ethylaminocarbonyl group, N-ethyl-N-isobutylaminocarbonyl group, N-t-butyl-N-ethylaminocarbonyl group, N-ethyl-Nn-pentylaminocarbonyl group, and N-ethyl-Nn-hexylaminocarbonyl group. 1-18 Alkylamino group; dicyclopropylaminocarbonyl group, dicyclobutylaminocarbonyl group, dicyclopentylaminocarbonyl group, dicyclohexylaminocarbonyl group, etc. 3-18 Alicyclic aminocarbonyl group; diphenylaminocarbonyl group, phenylnaphthylaminocarbonyl group, etc. 6-18 arylaminocarbonyl group" and the like.

[0034] In this specification, "C 1-18 The term "hydrocarbyl carbonyl amino group" means "C 1-18 The term "hydrocarbyl carbonyl group" refers to a group in which an amino group is bonded to a "hydrocarbyl carbonyl group." "C 1-18The "hydrocarbylcarbonylamino group" is not particularly limited, and examples thereof include a "C10 carbonylamino group" such as a methylcarbonylamino group, an ethylcarbonylamino group, an n-propylcarbonylamino group, an i-propylcarbonylamino group, an n-butylcarbonylamino group, an i-butylcarbonylamino group, a sec-butylcarbonylamino group, a t-butylcarbonylamino group, an n-pentylcarbonylamino group, an i-pentylcarbonylamino group, or an n-hexylcarbonylamino group. 1-18 Alkylcarbonylamino group; cyclopropylcarbonylamino group, cyclobutylcarbonylamino group, cyclopentylcarbonylamino group, cyclohexylcarbonylamino group, etc. 3-18 Alicyclic carbonylamino group; phenylcarbonylamino group, naphthylcarbonylamino group, acenaphthylcarbonylamino group, phenanthrenylcarbonylamino group, anthracenylcarbonylamino group, etc. 6-18 arylcarbonylamino group" and the like.

[0035] In this specification, "C 1-18 The term "hydrocarbylaminocarbonyloxy group" means "C 1-18 The term "hydrocarbylaminocarbonyl group" refers to a group in which an oxygen atom (-O-) is bonded to a "hydrocarbylaminocarbonyl group." "C 1-18 The "hydrocarbylaminocarbonyloxy group" is not particularly limited, and examples thereof include "C methylaminocarbonyloxy group, ethylaminocarbonyloxy group, n-propylaminocarbonyloxy group, etc. 1-18 "C alkylaminocarbonyloxy group"; "C cyclopropylaminocarbonyloxy group, cyclohexylaminocarbonyloxy group, etc. 3-18 Alicyclic aminocarbonyloxy group; phenylaminocarbonyloxy group, 1-naphthylaminocarbonyloxy group, etc. 6-18 arylaminocarbonyloxy group" and the like.

[0036] As used herein, "diC 1-18 The hydrocarbylaminocarbonyloxy group is a di-C 1-18The term "hydrocarbylaminocarbonyl group" refers to a group in which an oxygen atom (-O-) is bonded to a "hydrocarbylaminocarbonyl group." "JiC 1-18 The hydrocarbylaminocarbonyloxy group is not particularly limited, and examples thereof include "di-C" such as dimethylaminocarbonyloxy group, diethylaminocarbonyloxy group, and di-n-propylaminocarbonyloxy group. 1-18 alkylaminocarbonyloxy group" and the like.

[0037] In this specification, "C 1-18 The term "hydrocarbylaminocarbonylamino group" means "C 1-18 "Hydrocarbylaminocarbonyl group" means a group bonded to an amino group. "C 1-18 The "alkylaminocarbonylamino group" is not particularly limited, and examples thereof include a "C alkylaminocarbonylamino group, such as a methylaminocarbonylamino group, an ethylaminocarbonyloxy group, and an n-propylaminocarbonylamino group. 1-18 "C alkylaminocarbonylamino group"; "C cyclopropylaminocarbonylamino group, cyclohexylaminocarbonylamino group, etc. 3-18 Alicyclic aminocarbonylamino group; phenylaminocarbonylamino group, 1-naphthylaminocarbonylamino group, etc. 6-18 arylaminocarbonylamino group" and the like.

[0038] As used herein, "diC 1-18 The term "hydrocarbylaminocarbonylamino group" refers to a "diC 1-18 "Hydrocarbylaminocarbonyl group" means a group bonded to an amino group. "JiC 1-18 The hydrocarbylaminocarbonylamino group is not particularly limited, and examples thereof include "di-C" such as dimethylaminocarbonylamino group, diethylaminocarbonylamino group, and di-n-propylaminocarbonylamino group. 1-18 alkylaminocarbonylamino group" and the like.

[0039] In this specification, "C 1-18The term "hydrocarbyloxycarbonylamino group" means "C 1-18 "Hydrocarbyloxycarbonyl group" means a group bonded to an amino group. "C 1-18 The "hydrocarbyloxycarbonylamino group" is not particularly limited, and examples thereof include "C methoxycarbonylamino group, ethoxycarbonylamino group, n-propoxycarbonylamino group, i-propoxycarbonylamino group, n-butoxycarbonylamino group, t-butoxycarbonylamino group, etc. 1-18 alkoxycarbonylamino group; cyclopropyloxycarbonylamino group, cyclohexyloxycarbonylamino group, etc. 3-18 Alicyclic oxycarbonylamino group; phenyloxycarbonylamino group, 1-naphthyloxycarbonylamino group, etc. 6-18 aryloxycarbonylamino group" and the like.

[0040] In this specification, "C 1-18 The term "hydrocarbylthio group" means "C 1-18 The term "hydrocarbyl group" refers to a group having a sulfur atom (-S-) bonded to a "hydrocarbyl group." "C 1-18 The "hydrocarbylthio group" is not particularly limited, and examples thereof include a methylthio group, an ethylthio group, an n-propylthio group, an i-propylthio group, an n-butylthio group, an i-butylthio group, a t-butylthio group, an n-pentylthio group, an n-hexylthio group, and the like. 1-18 Alkylthio group; cyclopropylthio group, cyclobutylthio group, cyclopentylthio group, cyclohexylthio group, 2-methylcyclopentylthio group, 3-methylcyclopentylthio group, 2-methylcyclohexylthio group, 3-methylcyclohexylthio group, 4-methylcyclohexylthio group, etc. 3-18 Alicyclic thio group; phenylthio group, 1-naphthylthio group, 2-naphthylthio group, acenaphthylthio group, phenanthrenylthio group, anthracenylthio group, etc. 6-18 arylthio group" and the like.

[0041] In this specification, "C 1-18The term "hydrocarbylsulfinyl group" means "C 1-18 The term "hydrocarbyl group" refers to a group having a sulfinyl group (-S(=O)-) bonded to a "hydrocarbyl group." "C 1-18 The "hydrocarbylsulfinyl group" is not particularly limited, and examples thereof include a "C methylsulfinyl group, an ethylsulfinyl group, an n-propylsulfinyl group, an i-propylsulfinyl group, an n-butylsulfinyl group, a t-butylsulfinyl group, a pentylsulfinyl group, a hexylsulfinyl group, etc. 1-18 "C alkylsulfinyl group"; "C alkylsulfinyl group" such as cyclopropylsulfinyl group, cyclobutylsulfinyl group, cyclopentylsulfinyl group, cyclohexylsulfinyl group, 2-methylcyclopentylsulfinyl group, 3-methylcyclopentylsulfinyl group, 2-methylcyclohexylsulfinyl group, 3-methylcyclohexylsulfinyl group, and 4-methylcyclohexylsulfinyl group; 3-18 Alicyclic sulfinyl group; phenylsulfinyl group, naphthylsulfinyl group, acenaphthylsulfinyl group, phenanthrenylsulfinyl group, anthracenylsulfinyl group, etc. 6-18 arylsulfinyl group" and the like.

[0042] In this specification, "C 1-18 The term "hydrocarbylsulfonyl group" means "C 1-18 It means a group in which a sulfonyl group (-SO2-) is bonded to a "hydrocarbyl group." "C 1-18 The hydrocarbylsulfonyl group is not particularly limited, and examples thereof include a methylsulfonyl group, an ethylsulfonyl group, an n-propylsulfonyl group, an i-propylsulfonyl group, an n-butylsulfonyl group, a t-butylsulfonyl group, a pentylsulfonyl group, etc. 1-18 Alkylsulfonyl group; cyclopropylsulfonyl group, cyclobutylsulfonyl group, cyclopentylsulfonyl group, cyclohexylsulfonyl group, 2-methylcyclopentylsulfonyl group, 3-methylcyclopentylsulfonyl group, 2-methylcyclohexylsulfonyl group, 3-methylcyclohexylsulfonyl group, 4-methylcyclohexyl group, etc.3-18 Alicyclic sulfonyl group; phenylsulfonyl group, naphthylsulfonyl group, acenaphthylsulfonyl group, phenanthrenylsulfonyl group, anthracenylsulfonyl group, etc. 6-18 arylsulfonyl group" and the like.

[0043] In this specification, the term "acid dissociable group" refers to a group that substitutes a hydrogen atom of a carboxy group or a hydroxy group (including a phenolic hydroxyl group), and that dissociates due to the action of an acid. The "acid dissociable group" is not particularly limited, and examples thereof include t-butyl group, t-amyl group, 1,1-dimethylpropyl group, 1-methyl-1-cyclopentyl group, 1-ethyl-1-cyclopentyl group, 1-methyl-1-cyclohexyl group, 1-ethyl-1-cyclohexyl group, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-(1-methoxy-2-methylpropan-2-yl)cyclopentyl group, 1-(1-ethoxy-2-methylpropan-2-yl)cyclopentyl group, and the like.

[0044] In this specification, the term "optionally having a substituent" is not particularly limited as long as it is chemically permissible and has the effect of the present invention. Examples of the "substituent" include (1) a halogen atom, (2) a hydroxy group, (3) a thiol group, (4) a nitro group, (5) a cyano group, (6) a carboxy group, (7) an amino group, (8) a sulfo group, (9) a group in which a hydrogen atom of a carboxy group or a hydroxy group is substituted with an acid dissociable group, or (10) a C group in which at least a part of the hydrogen atoms may be substituted with the above (1) to (9). 1-8 Hydrocarbyl group, C 1-8 Hydrocarbyloxy group, C 1-8 Hydrocarbyl carbonyl group, C 1-8 Hydrocarbylcarbonyloxy group, C 1-8 Hydrocarbyloxycarbonyl group, C 1-8 Hydrocarbyloxycarbonyloxy group, C 1-8 Hydrocarbylamino group, diC 1-8 Hydrocarbylamino group, C 1-8Hydrocarbylaminocarbonyl group, diC 1-8 Hydrocarbylaminocarbonyl group, C 1-8 Hydrocarbylcarbonylamino group, C 1-8 Hydrocarbylaminocarbonyloxy group, diC 1-8 Hydrocarbylaminocarbonyloxy group, C 1-8 Hydrocarbylaminocarbonylamino group, diC 1-8 Hydrocarbylaminocarbonylamino group, C 1-8 Hydrocarbyloxycarbonylamino group, C 1-8 Hydrocarbylthio group, C 1-8 Hydrocarbylsulfinyl group, C 1-8 Examples of the hydrocarbylsulfonyl group include a divalent carbon atom at any position except for the terminal of the above-mentioned substituent, which may be replaced with -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO- (provided that adjacent divalent carbon atoms are not replaced at the same time).

[0045] [1-1. (A) Resin component whose solubility in developer changes due to the action of acid] The resist composition according to the present embodiment contains (A) a resin component whose solubility in a developer changes under the action of an acid. The component (A) may be any known or commonly used resin, and is not particularly limited. From the viewpoint of changing the solubility in a developer under the action of an acid, it is preferable that the component (A) contains an acid-dissociable group.

[0046] The acid dissociable group may be contained in the component (A) as a structural unit (a1) having an acid dissociable group. For example, the structural unit (a1) having the acid dissociable group may be copolymerized with any other structural unit (which may be any polymerization such as alternating copolymerization, random copolymerization, block copolymerization, graft copolymerization, etc.) to contain the acid dissociable group in the component (A). Furthermore, the component (A) may contain, as the optional structural unit, a structural unit (a2) having a phenolic hydroxyl group, a structural unit (a3) ​​having a lactone-containing alicyclic group, a structural unit (a4) having a polar group-containing hydrocarbyl group, or other structural units.

[0047] The "acid dissociable group", "structural unit (a1) having an acid dissociable group", "structural unit (a2) having a phenolic hydroxyl group", "structural unit (a3) ​​having an alicyclic group", "structural unit (a4) having a polar group-containing hydrocarbyl group", and "other structural units" will each be described below.

[0048] [1-1-1. Acid dissociable group] The acid dissociable group is not particularly limited, and known and commonly used ones can be used. For example, the acid dissociable group can be an acid dissociable group G represented by the following formula (g-1) or (g-2), which is a group that substitutes a hydrogen atom of a carboxy group, a hydroxy group (including a phenolic hydroxy group), etc., and dissociates under the action of an acid.

[0049] [ka] [ka]

[0050] The acid dissociable group G is not particularly limited as long as it dissociates under the action of an acid, and any known and commonly used group can be used. For example, the acid dissociable group G in this embodiment can be an acid dissociable group represented by the following formula (g-3) in which the carbon bonded to the carboxyl group or hydroxyl group is a tertiary carbon.

[0051] TIFF2024169053000003.tif26167

[0052] In the general formula (g-3), "R g1 " is an optionally substituted C 1-12In the hydrocarbyl group, a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2- (however, adjacent divalent carbon atoms are not replaced at the same time). Also, "R g2 " and "R g3 " each independently represents a C 1-12 a hydrocarbyl group in which a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time), or R g2 and R g3 C which may have a substituent in combination 3-18 It may constitute an alicyclic group or a 3- to 18-membered non-aromatic heterocyclic group.

[0053] In general formula (g-3), R g1 As the C, a part of hydrogen atoms may be substituted with a substituent from the viewpoint of improving dissociation property by the action of an acid. 1-6 Alkyl group, C 2-12 Alkenyl group, C 3-18 Alicyclic group, C 2-18 Aryl group or C 7-12 An aralkyl group in which a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2- (however, adjacent divalent carbon atoms are not replaced at the same time), and a C 1-6 Alkyl group, C 2-12 Alkenyl group, C 3-18 Alicyclic group, C 2-18An aryl group in which a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time) is more preferred. Specific examples of the above-mentioned alkyl group include, but are not limited to, C groups such as a methyl group, an ethyl group, and a propyl group. 1-6 Alkyl groups: vinyl, allyl, 1-propenyl, 1-butenyl, pentenyl, etc. 2-12 Alkenyl groups: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopent-1-en-1-yl, 2-methylcyclopent-1-en-1-yl, cyclohex-1-en-1-yl, 4-methylcyclohex-1-en-1-yl, cyclopentylidenemethyl, and other C 3-18 Alicyclic groups: phenyl, tolyl, xylyl, mesityl, etc. 2-18 Examples of the alkyl group include an aryl group.

[0054] In addition, in the general formula (g-3), R g2 and R g3 From the viewpoint of improving dissociation by the action of acid, R g2 and R g3 C which may have a substituent in combination 3-18 It is preferable that the ring structure constitutes an alicyclic group or a 3- to 18-membered non-aromatic heterocyclic group. Specific examples of the above-mentioned cycloalkyl ethers are not particularly limited and include C cycloalkyl ethers having a cyclopentane skeleton, a cyclohexane skeleton, a cycloheptane skeleton, a cyclooctane skeleton, a cyclononane skeleton, a cyclodecane skeleton, a cyclododecane skeleton, a cyclopentene skeleton, a cyclohexene skeleton, a cycloheptene skeleton, a cyclooctene skeleton, a cyclodecene skeleton, a norbornane skeleton, an adamantane skeleton, a tricyclodecane skeleton, a tetracyclododecane skeleton, a norbornene skeleton, and a tricyclodecene skeleton. 3-18 An alicyclic group is also included.

[0055] The acid dissociable group G is not particularly limited, and examples thereof include a 1-methylcyclopentyl group, a 1-ethylcyclopentyl group, a 1-phenylcyclopentyl group, a 1-tolylcyclopentyl group, a 1-methylcyclohexyl group, a 1-ethylcyclohexyl group, a 1-phenylcyclohexyl group, a 1-tolylcyclohexyl group, a 1-(naphthalen-2-yl)cyclohexyl group, a 1-(1-methoxy-2-methylpropan-2-yl)cyclopentyl group, a 1-(1-ethoxy-2-methylpropan-2-yl)cyclopentyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, and a 2-phenyladamantan-2-yl group.

[0056] [1-1-2. Structural unit (a1) having an acid dissociable group] The structural unit (a1) having an acid-dissociable group is not particularly limited, and may be any known or commonly used one. For example, structural units represented by the following formulae (a1-1) and (a1-2) may be used as (a1).

[0057] [ka]

[0058] In the above formulas (a1-1) and (a1-2), "R α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and "G" represents the acid-dissociable group G described above. In addition, in the formula (a1-2), "L a1 " represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2-; "Ar a1 " is an optionally substituted C 6-18 Represents an arylene group, and "-OG" is Ar a1 This indicates that "-OG" is attached to one of the two ends.

[0059] In addition, C which may have a substituent 6-18The arylene group is not particularly limited, and examples thereof include a 1,4-phenylene group, a 1,3-phenylene group, a 1,2-phenylene group, a 1,4-naphthylene group, a 1,5-naphthylene group, a 1,8-naphthylene group, a 4,4'-biphenylene group, an anthracenediyl group, a phenanthrenediyl group, a naphthacenediyl group, a pyrenediyl group, a perylenediyl group, and a chrysenediyl group, in which at least one hydrogen atom may be substituted with a substituent.

[0060] The structural unit (a1-1) having an acid-dissociable group is not particularly limited, and examples thereof include structural units represented by the following formula: α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0061] [ka] TIFF2024169053000006.tif36168 TIFF2024169053000007.tif44168

[0062] The structural unit (a1-2) having an acid-dissociable group is not particularly limited, and examples thereof include structural units represented by the following formula: α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0063] [ka]

[0064] The lower limit of the content of the "structural unit (a1) having an acid dissociable group" relative to all structural units constituting the component (A) is preferably 10 mol%, more preferably 20 mol%, even more preferably 25 mol%, and particularly preferably 30 mol%. The upper limit of the content is preferably 90 mol%, more preferably 80 mol%, even more preferably 75 mol%, and particularly preferably 70 mol%. By setting the content of the structural unit (a1) having an acid dissociable group within the above range, it is possible to ensure sufficient dissolution contrast in the developer between the part of the component (A) that has been treated with acid and the part that has not been treated with acid.

[0065] [1-1-3. Structural unit (a2) having a phenolic hydroxyl group] The structural unit (a2) having a phenolic hydroxyl group is not particularly limited, and may be any known or commonly used one. For example, the structural unit represented by the following formula (a2-1) may be used as (a2).

[0066] [ka]

[0067] In formula (a2-1), “R α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and "L a2 " represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2-; a2 " is an optionally substituted C 6-18 Represents an arylene group, and "-OH" represents Ar a2 It represents that one of the two ends of the hydroxyl group is bonded to the other end of the molecule. a2 " is not particularly limited, and for example, "Ar a1 " and similar C 6-18 Examples of the alkyl group include an arylene group and the like. 6-18 One or more hydrogen atoms of the arylene group may be replaced by a substituent.

[0068] The structural unit (a2-1) having a phenolic hydroxyl group is not particularly limited, and examples thereof include structural units represented by the following formula: α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0069] [ka]

[0070] The lower limit of the content of the "structural unit (a2) having a phenolic hydroxyl group" relative to all structural units constituting the component (A) is preferably 5 mol%, more preferably 10 mol%, even more preferably 20 mol%, and particularly preferably 30 mol%. The upper limit of the content is preferably 90 mol%, more preferably 80 mol%, even more preferably 70 mol%, and particularly preferably 60 mol%. By setting the content of the structural unit (a2) having a phenolic hydroxyl group within the above range, the sensitivity of the component (A) when irradiated with radiation can be further improved.

[0071] [1-1-4. Structural unit (a3) ​​having a lactone-containing alicyclic group] The structural unit (a3) ​​having a lactone-containing alicyclic group is not particularly limited as long as it is a structural unit having an alicyclic group containing a cyclic ester, i.e., lactone (-C(=O)-O-), and any known and commonly used one can be used. The lactone-containing alicyclic group may be monocyclic or polycyclic. By incorporating (a3), the adhesion of the resist to the substrate can be improved. As (a3), for example, a structural unit represented by the following formula (a3-1) can be used.

[0072] [ka]

[0073] In formula (a3-1), “R α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and "L a3" represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2-; "Lac" represents a lactone-containing alicyclic group represented by the following formulae (l-1) to (l-4); any hydrogen atom on the lactone-containing alicyclic group is L; a3 and one or more other hydrogen atoms may be replaced by a substituent.

[0074] [ka]

[0075] In formulas (l-3) and (l-4), "L a3’ " is -O-, -S-, or C which may contain -O- or -S-. 1-3 Represents an alkylene group.

[0076] The structural unit (a3-1) having a lactone-containing alicyclic group is not particularly limited, and examples thereof include structural units represented by the following formula. α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0077] [ka]

[0078] The lower limit of the content of the "structural unit (a3) ​​having a lactone-containing alicyclic group" relative to all structural units constituting the component (A) is preferably 5 mol%, more preferably 10 mol%, even more preferably 20 mol%, and particularly preferably 30 mol%. The upper limit of the content is preferably 60 mol%, more preferably 55 mol%, and even more preferably 50 mol%. By setting the content of the structural unit (a3) ​​having a lactone-containing alicyclic group within the above range, it is possible to improve the adhesion of the resist to the substrate while maintaining a balance with other structural units.

[0079] [1-1-5. Structural unit (a4) having a polar group-containing hydrocarbyl group] The structural unit (a4) having a polar group-containing hydrocarbyl group is not particularly limited, and any known or commonly used structural unit can be used. By including (a4), the acid diffusion length of the component (A) can be appropriately adjusted while maintaining the hydrophilicity of the component (A).

[0080] Examples of the polar group of (a4) include a hydroxy group, a cyano group, a carboxy group, and a haloalkyl group. The hydrocarbyl group is a C group in which one or more hydrogen atoms are substituted with a polar group and one or more hydrogen atoms may be substituted with a substituent. 1-18 C is preferably a hydrocarbyl group, in which one or more hydrogen atoms are substituted by a polar group and one or more hydrogen atoms may be substituted by a substituent. 3-18 An alicyclic group is more preferable, and an adamantyl group, a norbornyl group, an isobornyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, or a tricyclodecyl group in which one or more hydrogen atoms are substituted by a polar group and one or more hydrogen atoms may be further substituted by a substituent is even more preferable.

[0081] As (a4), for example, a structural unit represented by the following formula (a4-1) can be used.

[0082] [ka]

[0083] In formula (a4-1), “R α " represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and "L a4 " represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S- or -SO2-; "Pol" represents a C group in which one or more hydrogen atoms are substituted with a polar group and one or more hydrogen atoms may be substituted with a substituent. 1-18 Represents a hydrocarbyl group.

[0084] The lower limit of the content of the "structural unit (a4) having a polar group-containing hydrocarbyl group" relative to all structural units constituting the component (A) is preferably 1 mol%, more preferably 2 mol%, and even more preferably 5 mol%. The upper limit of the content is preferably 40 mol%, more preferably 35 mol%, and even more preferably 30 mol%. By setting the content of the structural unit (a4) having a polar group-containing hydrocarbyl group within the above range, it is possible to appropriately adjust the acid diffusion length while maintaining hydrophilicity, and to achieve a balance with other structural units.

[0085] [1-1-6. Other structural units] The component (A) may contain any other structural unit in addition to the above (a2) to (a4). The optional structural unit is not particularly limited, and examples thereof include structural units having an alicyclic group containing a skeleton such as lactam, sulfone, sultone, or carbonate; structural units having styrene or a styrene derivative; and the like.

[0086] [1-1-7. (A) Component] When the component (A) contains both a "structural unit (a1) having an acid dissociable group" and a "structural unit (a2) having a phenolic hydroxyl group," the molar ratio of the structural units (a1) to (a2) is preferably 2:8 to 8:2, more preferably 3:7 to 7:3, and even more preferably 4:6 to 6:4.

[0087] Furthermore, when the component (A) contains all of the "structural unit (a1) having an acid dissociable group," the "structural unit (a3) ​​having a lactone-containing alicyclic group," and the "structural unit (a4) having a polar group-containing hydrocarbyl group," the molar ratio of the structural units (a1), (a3), and (a4) is preferably 2-6:2-6:1-3, more preferably 3-5:3-5:1-3, and even more preferably 3-5:3-5:2.

[0088] The method for synthesizing the component (A) is not particularly limited, and examples include a method in which monomers that derive each structural unit are dissolved in a polymerization solvent, and a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate is added thereto to polymerize.

[0089] The weight average molecular weight (Mw) of component (A) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, and the lower limit is preferably 1000, more preferably 2000, and even more preferably 3000. The upper limit of Mw is preferably 50000, more preferably 30000, and even more preferably 20000. When the Mw of component (A) is at least the above-mentioned lower limit, the etching properties and the cross-sectional shape of the resist pattern can be improved, and when it is no more than the above-mentioned upper limit, the solubility of component (A) can be maintained.

[0090] The dispersity (Mw / Mn) of the component (A) is not particularly limited, and is, for example, preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and even more preferably 1.0 to 2.0. Here, Mn means number average molecular weight. By setting the dispersity of the component (A) within the above range and narrowing the molecular weight distribution, the reactivity of the resist composition can be made uniform.

[0091] The content of component (A) in the total solid components of the resist composition is preferably 1 to 80 mass%, more preferably 5 to 75 mass%, and even more preferably 10 to 70 mass%. Here, the "total solid content" refers to all components of the resist composition other than the solvent.

[0092] [1-2.(B) Polyacid salts] The resist composition according to the present embodiment contains (B) a polyacid salt. The (B) component may be any known or commonly used one, and is not particularly limited. The (B) component, a polyacid salt (also called polyoxometalate), can act as both an acid generator and an acid diffusion inhibitor, and can appropriately fine-tune the range in which acid is generated and diffused by exposure depending on the exposure dose, etc. In addition, the acid strength, absorbency to the exposure light source, etc. can be adjusted by combining the anion moiety and the cation moiety of the polyacid salt.

[0093] Polyacids are compounds with the general formula [M x O y ] n- (wherein x, y, and n are all natural numbers). The metal atom M constituting the polyacid is called a polyatom, and examples thereof include Mo (hexavalent or pentavalent), W (hexavalent or pentavalent), V (pentavalent), Nb (pentavalent), and Ta (pentavalent). Polyacids include isopolyacids composed of the polyatom M and an oxygen acid, and polyatoms M and oxygen, as well as different types of atoms X (for example, heteroatoms X such as P 5+ , Si 4+ , Ge 4+ , B 3+ Heteropolyacids ([X w M x O y ] n- (wherein w, x, y, and n are all natural numbers)

[0094] Here, the polyacid salt is composed of an anion portion of an isopolyacid or heteropolyacid and a corresponding counter cation. In the following, the anion portion and the cation portion of the polyacid salt will be separately described.

[0095] [1-2-1. Anion part of polyacid salt] The anion portion of the polyacid salt is composed of an isopolyacid anion or a heteropolyacid anion. Examples of the isopolyacid anion include an isopolyoxomolybdate anion, an isopolyoxotungstate anion, an isopolyoxovanadate anion, an isopolyoxoniobate anion, and an isopolyoxotantalate anion. The isopolyoxomolybdate anion is, for example, [MoO4] 2- , [Mo7O 24 ] 6- , [Mo8O 26 ] 4- Examples of the isopolyoxotungstate anion include [WO 13 ] 2- , [W5O 16 ] 2- ,[W7O 22 ] 2- ,[W7O 24 ] 6- , [H z W 12 O 40 ] -(8-z) (where z is an integer from 1 to 4), [W 10 O 32 ] 4- , [H4W 11 O 38 ] 6- , [H7W 11 O 40 ] 7- , [HW5O 19 ] 7- , [H3W 11 O 22 ] 5- Examples of the isopolyoxovanadate anion include [VO 12 ] 4- , [V 10 O 28 ] 6- The isopolyoxoniobate anion may be, for example, [NbO 19 ] 8- , [Nb 10 O 28 ] 6- The isopolyoxotantalate anion may be, for example, [TaO 19 ] 8- , [Ta8O 21 ]2- etc. The above-mentioned isopolyoxomolybdate anion, isopolyoxotungstate anion, isopolyoxovanadate anion, isopolyoxoniobate anion, and isopolyoxotantalate anion include various isomers and the like.

[0096] Examples of the heteropoly acid anion include a heteropolyoxomolybdate anion, a heteropolyoxotungstate anion, a heteropolyoxovanadate anion, a heteropolyoxoniobate anion, and a heteropolyoxotantalate anion. Examples of the heteropolyoxomolybdate anion include phosphomolybdate anion, silicomolybdate anion, boromolybdate anion, phosphotungstomolybdate anion, cobalt molybdate anion, arsenic molybdate anion, germanium molybdate anion, etc. Examples of the heteropolyoxotungstate anion include phosphotungstate anion, silicotungstate anion, borotungstate anion, cobalt tungstate anion, arsenic tungstate anion, germanium tungstate anion, etc. Examples of the heteropolyoxovanadate anion include phosphomolybdovanadate anion, phosphomolybdotungstomolybdate anion, boromolybdovanadate anion, boromolybdotungstovanadate anion, etc. The heteropolyoxomolybdate anion, heteropolyoxotungstate anion, heteropolyoxovanadate anion, etc. include Keggin type, Dawson type, Anderson type, and defective species and isomers thereof.

[0097] [1-2-2. Cation part of polyacid salt] The type of salt of a polyacid salt (isopolyoxometalate or heteropolyoxometalate) is not particularly limited, and may be a salt with a proton, an onium cation (such as an organic onium cation, an organic sulfonium cation, an organic iodonium cation, an organic quaternary ammonium cation, an organic phosphonium cation, etc.), an alkali metal ion, etc. From the viewpoint of improving the actinic ray or radiation sensitivity and varying the solvent solubility of the exposed and unexposed areas, the type of salt of a polyacid salt is preferably a salt with an onium cation, and among these, a salt with an organic sulfonium cation, an organic iodonium cation, or an organic quaternary ammonium cation is more preferable.

[0098] [1-2-2-1. Organic sulfonium cation] The organic sulfonium cation is not particularly limited, and any known and commonly used organic sulfonium cation can be used. Examples of the organic sulfonium cation include organic sulfonium cations represented by the formula (b-1).

[0099] [ka]

[0100] In formula (b-1), R 1A , R 1B and R 1C are each independently 1-18 represents a hydrocarbyl group or a 3- to 18-membered non-aromatic heterocyclic group, Above R 1A , R 1B and R 1C a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Also, the above R 1A , R 1B and R 1CThe hydrogen atom contained in the above may be, for example, (a) a halogen atom, (b) a haloalkyl group, (c) a hydroxy group, (d) a thiol group, (e) a nitro group, (f) a cyano group, (g) a carboxy group, (h) an amino group, (i) a sulfo group, (j) a group in which a hydrogen atom of a carboxy group or a hydroxy group is substituted with an acid dissociable group, or (k) a C group in which at least a part of the hydrogen atoms may be substituted with any of the above (a) to (j). 1-18 Hydrocarbyl group, C 1-18 Hydrocarbyloxy group, C 1-18 Hydrocarbyl carbonyl group, C 1-18 Hydrocarbylcarbonyloxy group, C 1-18 Hydrocarbyloxycarbonyl group, C 1-18 Hydrocarbyloxycarbonyloxy group, or C 1-18 A hydrocarbylthio group in which a divalent carbon atom at any position except the terminal of these substituents may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Further R 1A , R 1B and R 1C Any two of these are directly connected to each other via a single bond, or are divalent linking groups -O-, -S-, -C(=O)-, -S(=O)-, -S(=O)2-, -C(=O)O-, or C 1-3 They may be linked via an alkylene group to form a ring together with the sulfur atom in formula (b-1).

[0101] R in formula (b-1) 1A , R 1B and R 1C Each of the C groups independently may have a substituent. 2-18 It is preferably an aryl group. 2-18 The substituent of the aryl group is a halogen atom, a haloalkyl group, a hydroxy group, a nitro group, a cyano group, a C 1-12 A hydrocarbylthio group is preferred, a halogen atom, C 1-4A haloalkyl group or a nitro group is more preferred.

[0102] Specific examples of the organic sulfonium cation include dibutyl(pentyl)sulfonium cation, triethylsulfonium cation, (2-carboxyethyl)dimethylsulfonium cation, trimethylsulfonium cation, dimethylphenacylsulfonium cation, 1-(4-hydroxynaphthalene-1-yl)hexahydrothiopyrylium cation, dimethylphenylsulfonium cation, triphenylsulfonium cation, tris(4-methylphenyl)sulfonium cation, 4-methoxyphenyldiphenylsulfonium cation, 4-iodophenyldiphenylsulfonium cation, tris(4-fluorophenyl)sulfonium cation, 1-phenylhexahydrothiopyrylium cation, (ethane-1,2-diylbisoxy)bis(4,1-phenylene)bis(diphenylsulfonium) dication, (thiodi-4,1-phenylene)bis(diphenylsulfonium) dication, di(naphthalene-1-yl)(fluorophenyl)sulfonium cation, and the like. phenyl)sulfonium cation, phenylbis(2-(trifluoromethyl)phenyl)sulfonium cation, mesitylbis(2-(trifluoromethyl)phenyl)sulfonium cation, bis(3,5-difluorophenyl)(phenyl)sulfonium cation, tris(3,5-difluorophenyl)sulfonium cation, (4-(dodecanoyloxy-3,5-dimethylphenyl))diphenylsulfonium cation, diphenyl(3-(trifluoromethoxy)phenyl)sulfonium cation, (4-(1-adamantylcarbonyloxy)phenyl)diphenylsulfonium cation, (4-phenylthiophenyl)diphenylsulfonium cation, 5-phenyl-5H-thianthren-5-ium cation, 5-(2,5-dimethylphenyl)thianthren-5-ium cation, 5-phenyl-5H-dibenzo[b,d]thiophen-5-ium cation 5-(3-(trifluoromethyl)phenyl)-5H-dibenzo[b,d]thiophene-5-ium cation, 1-(4-(t-butyl)phenyl)-1H-benzo[b]thiophene-1-ium cation, methyldiphenylsulfonium cation, (2-bromoethyl)diphenylsulfonium cation, (3-chloropropyl)diphenylsulfonium cation, benzyl(4-hydroxyphenyl)methylsulfonium cation, (4-hydroxyphenyl)methyl(2-methylbenzyl)sulfonium cation, 4-hydroxyphenyldimethylsulfonium cation, diphenyl(methyl)sulfonium cation, diphenyl(4-(phenylthio)phenyl)sulfonium cation, (2-bromoethyl)diphenylsulfonium cation, dimesityl(trifluoromethyl)sulfonium cation, tri-p-tolylsulfonium cation, etc. can be exemplified.

[0103] [1-2-2-2. Organic iodonium cation] The organic iodonium cation is not particularly limited, and any known and commonly used organic iodonium cation can be used. Examples of the organic iodonium cation include the organic iodonium cation represented by the formula (b-2).

[0104] [ka]

[0105] In formula (b-2), R 2A and R 2B are each independently 1-18 represents a hydrocarbyl group or a 3- to 18-membered non-aromatic heterocyclic group, Above R 2A and R 2B a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Also, the above R 2A and R 2BThe hydrogen atom contained in the above may be, for example, (a) a halogen atom, (b) a haloalkyl group, (c) a hydroxy group, (d) a thiol group, (e) a nitro group, (f) a cyano group, (g) a carboxy group, (h) an amino group, (i) a sulfo group, (j) a group in which a hydrogen atom of a carboxy group or a hydroxy group is substituted with an acid dissociable group, or (k) a C group in which at least a part of the hydrogen atoms may be substituted with any of the above (a) to (j). 1-18 Hydrocarbyl group, C 1-18 Hydrocarbyloxy group, C 1-18 Hydrocarbyl carbonyl group, C 1-18 Hydrocarbylcarbonyloxy group, C 1-18 Hydrocarbyloxycarbonyl group, or C 1-18 A hydrocarbyloxycarbonyloxy group in which a divalent carbon atom at any position except the terminal of these substituents may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Further R 2A and R 2B are directly connected to each other by a single bond, or are connected to each other by a divalent linking group, -O-, -S-, -C(=O)-, -S(=O)-, -S(=O)2-, -C(=O)O-, or C 1-3 They may be linked via an alkylene group to form a ring together with the iodine atom in formula (b-2).

[0106] R in formula (b-2) 2A and R 2B Each of the C groups independently may have a substituent. 2-18 It is preferably an aryl group. 2-18 The substituent of the aryl group is a halogen atom, a haloalkyl group, a hydroxyl group, a nitro group, a cyano group, a C 1-12 Hydrocarbyl group, C 1-12 Hydrocarbyloxy group, C 1-12 Hydrocarbyl carbonyl group, C 1-12 Hydrocarbylcarbonyloxy group, C 1-12Hydrocarbyloxycarbonyl group, or C 1-12 Hydrocarbyloxycarbonyloxy group is preferred, halogen atom, C 1-4 Haloalkyl group, nitro group, C 1-8 Hydrocarbyl group, C 1-8 It is preferably a hydrocarbyloxy group.

[0107] Specific examples of the organic iodonium cation include ethynyl(phenyl)iodonium cation, diphenyliodonium cation, bis(4-(t-butyl)phenyl)iodonium cation, (2-carboxyphenyl)(phenyl)iodonium cation, (4-nitrophenyl)(phenyl)iodonium cation, (3-(trifluoromethyl)phenyl)(2,4,6-trimethylphenyl)iodonium cation, bis(4-fluorophenyl)iodonium cation, (4-(bromomethyl)phenyl)(2,4,6-trimethoxyphenyl)iodonium cation, 4-biphenylyl(2,4,6-trimethoxyphenyl)iodonium cation, bis(2,4,6-trimethylphenyl)iodonium cation, 4-isopropyl-4'-methyldiphenyliodonium cation, (4-(trifluoromethyl)phenyl)iodonium cation, Examples of the iodonium cation include ((4-trifluoromethyl)phenyl)(2,4,6-trimethoxyphenyl)iodonium cation, (5-fluoro-2-nitrophenyl)(2,4,6-trimethoxyphenyl)iodonium cation, (3-bromophenyl)(mesityl)iodonium cation, bis(4-bromophenyl)iodonium cation, (3,5-dichlorophenyl)(2,4,6-trimethoxyphenyl)iodonium cation, (4-methylphenyl)(2,4,6-trimethylphenyl)iodonium cation, (3-methylphenyl)(2,4,6-trimethylphenyl)iodonium cation, (2-methylphenyl)(2,4,6-trimethylphenyl)iodonium cation, and phenyl(2,4,6-trimethoxyphenyl)iodonium cation.

[0108] [1-2-2-3. Organic quaternary ammonium cations] The organic quaternary ammonium cation is not particularly limited, and any known and commonly used organic quaternary ammonium cation can be used. Examples of the organic quaternary ammonium cation include the organic quaternary ammonium cation represented by the formula (b-3).

[0109] [ka]

[0110] In formula (b-3), R 3A , R 3B , R 3C and R 3D are each independently 1-18 represents a hydrocarbyl group or a 3- to 18-membered non-aromatic heterocyclic group, Above R 3A , R 3B , R 3C and R 3D a divalent carbon atom at any position except the terminal may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Also, the above R 3A , R 3B , R 3C and R 3D The hydrogen atom contained in the above may be, for example, (a) a halogen atom, (b) a haloalkyl group, (c) a hydroxy group, (d) a thiol group, (e) a nitro group, (f) a cyano group, (g) a carboxy group, (h) an amino group, (i) a sulfo group, (j) a group in which a hydrogen atom of a carboxy group or a hydroxy group is substituted with an acid dissociable group, or (k) a C group in which at least a part of the hydrogen atoms may be substituted with any of the above (a) to (j). 1-18 Hydrocarbyl group, C 1-18 Hydrocarbyloxy group, C 1-18 Hydrocarbyl carbonyl group, C 1-18 Hydrocarbylcarbonyloxy group, C 1-18 Hydrocarbyloxycarbonyl group, C1-18 Hydrocarbyloxycarbonyloxy group, or C 1-18 A hydrocarbylthio group in which a divalent carbon atom at any position except the terminal of these substituents may be replaced by -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S-, or -SO2- (provided that adjacent divalent carbon atoms are not replaced at the same time); Further R 3A , R 3B , R 3C and R 3D Any two of these are directly connected to each other via a single bond, or are divalent linking groups -O-, -S-, -C(=O)-, -S(=O)-, -S(=O)2-, -C(=O)O-, or C 1-3 They may be linked via an alkylene group to form a ring together with the nitrogen atom in formula (b-3).

[0111] R in formula (b-3) 3A , R 3B , R 3C and R 3D Each of the C groups independently may have a substituent. 1-18 is preferably a hydrocarbyl group, C 1-12 Alkyl group, C 1-12 Alkenyl group, C 1-12 Alkynyl group, C 1-12 An alicyclic group is more preferred.

[0112] Specific examples of the organic quaternary ammonium cation include tetramethylammonium cation, tetraethylammonium cation, tetrapropylammonium cation, tetrabutylammonium cation, tetraheptylammonium cation, trimethylethylammonium cation, dimethyldiethylammonium cation, dimethylethylpropylammonium cation, methylethylpropylbutylammonium cation, trimethylphenylammonium cation, triethylhexylammonium cation, triethylcyclohexylammonium cation, and dodecyltrimethylammonium cation.

[0113] [1-2-3.(B) component] The method for synthesizing the polyacid salt, which is the component (B), is not particularly limited, and any known and commonly used method can be used. Examples of the method for synthesizing the polyacid salt include a salt exchange method and an ion exchange method.

[0114] The content of the component (B) in the total solid components of the resist composition is preferably from 30 to 90 mass %, more preferably from 35 to 85 mass %, and even more preferably from 40 to 80 mass %.

[0115] By including a polyacid salt as component (B) in the resist composition, the absorption of light sources such as DUV, XUV, and EUV can be increased. In addition, component (B) can play the role of an acid diffusion controller and an acid generator depending on the relationship with the acid generator and the acid diffusion controller. In addition, the combination of the anion part and the cation part of the polyacid salt, which is component (B), can finely adjust the properties such as acid strength. Furthermore, since component (B) functions as an acid generator, it is not necessary to use a sulfonic acid having a carbon atom substituted with fluorine as an acid generator, which is advantageous in terms of toxicity, environmental load, and the like.

[0116] [1-3. (C) Acid generator or acid diffusion controller] The resist composition according to the present embodiment may contain (C) an acid generator or an acid diffusion control agent. The (C) component may be a known or commonly used one, and is not particularly limited. The following will explain the (C-1) acid generator and (C-2) acid diffusion control agent in more detail.

[0117] [1-3-1.(C-1) Acid generator] The resist composition according to this embodiment may contain an acid generator (C-1). The acid generator is not particularly limited as long as it generates an acid upon exposure, and any known and commonly used acid generator can be used. By including an acid generator in the resist composition, the acid generated upon exposure acts on the acid-dissociable group contained in the component (A), thereby changing the solubility in the developer.

[0118] Examples of the acid generator include an onium salt compound, an N-sulfonyloxyimide compound, a sulfonimide compound, a halogen-containing compound, a diazoketone compound, etc. Among these, an onium salt compound can be preferably used as the acid generator.

[0119] [1-3-1-1. Onium salt compounds] The onium salt compound used as the acid generator is not particularly limited, and known and commonly used compounds can be used. As the anion part of the onium salt compound, a sulfonate anion can be suitably used. As the sulfonate anion, there is no particular limitation, and known and commonly used compounds can be used. As the cation part of the onium salt compound, there is no particular limitation, and known and commonly used compounds can be used. As the cation part, there is no particular limitation, and examples thereof include the above-mentioned organic sulfonium cation, organic iodonium cation, organic quaternary ammonium cation, etc.

[0120] As the onium salt compound, it is preferable to use an onium salt compound represented by the following formula (c-1).

[0121] [ka]

[0122] In formula (c-1), "R c11 " is a C in which one or more hydrogen atoms may be substituted with a substituent. 5-18 represents a hydrocarbyl group; "R c12 ~R c15" each independently represents a hydrogen atom, a fluorine atom, or a fluorinated alkyl group having 1 to 4 carbon atoms; "L c11 " represents -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2-; "L c12 " represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2-; n c1 represents an integer from 0 to 4; "U + " represents the cation portion of the onium salt compound.

[0123] [1-3-1-1-1. Anion part of onium salt compound] In the anion portion of the onium salt compound of formula (c-1), R c11 is a C in which one or more hydrogen atoms may be substituted by a substituent. 5-18 A hydrocarbyl group is preferred, and one or more hydrogen atoms may be substituted with a substituent. 5-18 Alicyclic group, C 2-18 An aryl group is more preferable, and one or more hydrogen atoms may be substituted by a substituent. 5-18 Alicyclic group or C 2-18 An aryl group is more preferred.

[0124] C in which one or more hydrogen atoms may be substituted 5-18 Alicyclic group or C 2-18 Specific examples of the aryl group include, but are not limited to, C aryl groups having a benzene skeleton, a naphthalene skeleton, an anthracene skeleton, a phenanthrene skeleton, and a biphenyl skeleton. 2-18Aryl group; C having a cyclopentane skeleton, a cyclohexane skeleton, a cycloheptane skeleton, a cyclooctane skeleton, a cyclononane skeleton, a cyclodecane skeleton, a cyclododecane skeleton, a cyclopentene skeleton, a cyclohexene skeleton, a cycloheptene skeleton, a cyclooctene skeleton, a cyclodecene skeleton, a norbornane skeleton, an adamantane skeleton, a tricyclodecane skeleton, a tetracyclododecane skeleton, a norbornene skeleton, a tricyclodecene skeleton, a bicyclo[2.2.1]heptane skeleton, a bicyclo[2.2.2]octane skeleton, a 9,10-dihydro-9,10-ethanoanthracene skeleton, or a 9,10-dihydro-9,10-[1,2]benzenoanthracene skeleton 5-18 An alicyclic group is also included.

[0125] R c11 Specific examples of the alkyl group include, but are not limited to, a phenyl group, a 1-naphthyl group, a 2-naphthyl group, an azulenyl group, an acenaphthyl group, a phenanthrenyl group, an anthracenyl group, a cyclopentyl group, a cyclopent-1-en-1-yl group, a 2-methylcyclopent-1-en-1-yl group, a cyclohex-1-en-1-yl group, an adamantan-1-yl group, an adamantan-2-yl group, a bicyclo[2.2.1]heptanyl group, a bicyclo[2.2.2]octanyl group, a bicyclo[2.2.1]heptenyl group, a bicyclo[2.2.2]octanyl group, a bicyclo[2.2.1]heptenyl group, a bicyclo[2.2.2]octanyl group, a bicyclo[2.2.2]octen ... Examples of such an alkyl group include a cyclo[2.2.2]octenyl group, a 9,10-dihydro-9,10-ethanoanthracen-11-yl group, a 9,10-dihydro-9,10-ethanoanthracen-12-yl group, a 9,10-dihydro-9,10-ethanoanthracen-9-yl group, a 9,10-dihydro-9,10-ethanoanthracen-10-yl group, a 9,10-dihydro-9,10-[1,2]benzenoanthracen-9-yl group, and a 9,10-dihydro-9,10-[1,2]benzenoanthracen-10-yl group.

[0126] In the anion portion of the onium salt compound in formula (c-1), R c12 ~R c15 are each preferably independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group having 1 to 4 carbon atoms, and R c12 or R c13Either of the following is a hydrogen atom, a fluorine atom, or C 1-2 is a fluorinated alkyl group, and R c14 or R c15 More preferably, any one of R is a fluorine atom. c12 or R c13 is a hydrogen atom, a fluorine atom, or a trifluoromethyl group, and R c14 and R c15 It is more preferable that all of the radicals are fluorine atoms.

[0127] In the anion portion of the onium salt compound in formula (c-1), L c11 is preferably -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2-, more preferably -C(=O)O-, -OCO, -CONH- or -SO2-, and further preferably -C(=O)O- or -OCO.

[0128] In the anion portion of the onium salt compound in formula (c-1), L c12 is preferably a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, -NHCO-, -NH(C=O)O-, -S- or -SO2-, more preferably a single bond, -O-, -C(=O)O- or -OCO-, and further preferably a single bond, -C(=O)O- or -OCO-.

[0129] [1-3-1-1-2. Cation part of onium salt compound] In the cation portion of the onium salt compound of formula (c-1), U + There is no particular limitation on the organic cation, and examples thereof include the above-mentioned organic sulfonium cation, organic iodonium cation, and organic quaternary ammonium cation. Above U +As the cation, any of the organic sulfonium cations, organic iodonium cations, and organic quaternary ammonium cations exemplified for the component (B) can be suitably used. Among these, the preferred cations are U + can also be preferably used as

[0130] [1-3-1-2.(C-1) component] The content of the component (C-1) in the resist composition's total solid components is preferably from 0.5 to 20 mass %, more preferably from 1 to 15 mass %, and even more preferably from 2 to 12 mass %.

[0131] [1-3-2.(C-2) Acid diffusion control agent] The resist composition according to the present embodiment may contain an acid diffusion control agent (C-2). The acid diffusion control agent is not particularly limited, and any known and commonly used one can be used. By containing an acid diffusion control agent in the resist composition, the diffusion of the acid generated from the acid generator by exposure can be controlled, and undesirable reactions can be suppressed from proceeding in the unexposed area.

[0132] The acid diffusion control agent can efficiently control the diffusion of the acid by using an agent that generates an acid weaker than the acid generated by the acid generator. The acid diffusion inhibitor is preferably a carboxylate compound represented by the following formula (c-2-1) or a sulfonate compound represented by the following formula (c-2-2).

[0133] [ka] [In formula (c-2-1), R c21 is a C in which one or more hydrogen atoms may be substituted by a substituent. 1-18 represents a hydrocarbyl group or a 5- to 18-membered non-aromatic heterocyclic group.

[0134] [ka] [In formula (c-2-2), R c22 is a C in which one or more hydrogen atoms may be substituted by a substituent. 1-18 It represents a hydrocarbyl group or a 5- to 18-membered non-aromatic heterocyclic group, and a fluorine atom and a trifluoromethyl group are not bonded to the carbon atom directly bonded to the sulfur atom of the sulfonate anion.

[0135] [1-3-2-1. Carboxylate compounds (C-2-1)] In the anion portion of the carboxylate compound of formula (c-2-1), R c21 is a C in which one or more hydrogen atoms may be substituted by a substituent. 1-18 A hydrocarbyl group or a 5- to 18-membered non-aromatic heterocyclic group is preferred, and one or more hydrogen atoms may be substituted with a substituent. 1-18 More preferably, it is a hydrocarbyl group, and one or more hydrogen atoms may be substituted by a substituent. 1-12 Alkyl group, C 3-18 Alicyclic group or C 2-18 An aryl group is more preferred.

[0136] The carboxylate anion is not particularly limited, and examples thereof include trifluoroacetate anion, pentafluoropropionate anion, 2-methoxyacetate anion, 2-methoxy-2-methylpropionate anion, 2-hydroxyacetate anion, 2-hydroxy-2-methylpropionate anion, 2-acetoxyacetate anion, adamantane-1-carboxylate anion, 9,10-dihydro-9,10-ethanoanthracene-11-carboxylate anion, 9,10-dihydro-9,10-[1,2]benzenoanthracene-9-carboxylate anion, benzoate anion, salicylate anion, 3-hydroxybenzoate anion, and 3-trifluoromethylbenzoate anion.

[0137] In the cation portion of the carboxylate compound of formula (c-2-1), U +There is no particular limitation on the organic cation, and examples thereof include the above-mentioned organic sulfonium cation, organic iodonium cation, and organic quaternary ammonium cation. Above U + As the cation, any of the organic sulfonium cations, organic iodonium cations, and organic quaternary ammonium cations exemplified for the component (B) can be suitably used. Among these, the preferred cations are U + can also be preferably used as

[0138] [1-3-2-2. Sulfonate compounds] In the anion portion of the sulfonate compound of formula (c-2-2), R c22 is a C in which one or more hydrogen atoms may be substituted by a substituent. 1-18 It is preferable that the carbon atom directly bonded to the sulfur atom of the sulfonate anion is a hydrocarbyl group or a 5- to 18-membered non-aromatic heterocyclic group, and that a fluorine atom and a trifluoromethyl group are not bonded to the carbon atom directly bonded to the sulfur atom of the sulfonate anion, and one or more hydrogen atoms may be substituted with a substituent. 1-18 More preferably, it is a hydrocarbyl group, and one or more hydrogen atoms may be substituted by a substituent. 1-12 Alkyl group, C 3-18 Alicyclic group or C 2-18 An aryl group is more preferred.

[0139] The sulfonate anion is not particularly limited, and examples thereof include camphorsulfonate anion, (adamantan-1-yl)methanesulfonate anion, (adamantane-1-carbonyloxy)ethane-1-sulfonate anion, cyclohexanesulfonate anion, 2-(cyclohexanecarbonyloxy)ethane-1-sulfonate anion, bicyclo[2.2.1]heptane-2-sulfonate anion, benzenesulfonate anion, and 4-methylbenzenesulfonate anion.

[0140] In the cation portion of the sulfonate compound of formula (c-2-2), U +There is no particular limitation on the organic cation, and examples thereof include the above-mentioned organic sulfonium cation, organic iodonium cation, and organic quaternary ammonium cation. Above U + As the cation, any of the organic sulfonium cations, organic iodonium cations, and organic quaternary ammonium cations exemplified for the component (B) can be suitably used. Among these, the preferred cations are U + can also be preferably used as

[0141] [1-3-2-3.(C-2) component] The content of the component (C-2) in the total solid components of the resist composition is preferably from 0.5 to 25 mass %, more preferably from 1 to 20 mass %, and even more preferably from 5 to 15 mass %.

[0142] [1-4. Organic solvents] The resist composition according to this embodiment may further contain an organic solvent. The organic solvent is not particularly limited, and any known and commonly used organic solvent may be used. The organic solvent is preferably an organic solvent that can dissolve or disperse the (A) component, the (B) component, and the (C-1) component or the (C-2) component uniformly when they are prepared.

[0143] Examples of the organic solvent include alcohol-based solvents, ether-based solvents, ketone-based solvents, amide-based solvents, ester-based solvents, hydrocarbon-based solvents, etc. These organic solvents may be used alone or in combination of two or more.

[0144] Specific examples of the organic solvent include alcohol-based solvents such as methanol, ethanol, 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 4-methyl-2-pentanol, ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; ether-based solvents such as diethyl ether, dipropyl ether, dibutyl ether, diisoamyl ether, tetrahydrofuran, anisole, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether; acetone, methylethyl ketone-based solvents such as N,N-dimethylformamide, N,N-diethylformamide, acetamide, etc.; amide-based solvents such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, propylene glycol monomethyl ether acetate (PGMEA), etc.; hydrocarbon-based solvents such as n-pentane, n-hexane, toluene, xylene, etc.; γ-butyrolactone, δ-valerolactone, γ-lactam, δ-lactam, dimethyl sulfoxide (DMSO), etc. The organic solvents may be used alone or in combination of two or more kinds.

[0145] The organic solvent contained in the resist composition according to this embodiment is preferably PGMEA, PGME, γ-butyrolactone, EL, or cyclohexanone. A mixed solvent obtained by mixing PGMEA and a polar solvent can also be suitably used. The mixing ratio (mass ratio) of the mixed solvent can be appropriately determined in consideration of the type of polar solvent, the compatibility between PGMEA and the polar solvent, etc. The mixing ratio (mass ratio) of the mixed solvent is preferably 1:9 to 9:1, and more preferably 2:8 to 8:2. As the polar solvent, for example, EL, cyclohexanone, etc. can be used.

[0146] There are no particular limitations on the amount of organic solvent in the resist composition and can be set as appropriate depending on the method for applying the resist composition to a substrate or the like, the coating film thickness, etc. The amount of organic solvent in the resist composition is preferably such that the solids concentration of the resist composition is 0.1 to 20 mass%, and more preferably 0.2 to 15 mass%.

[0147] [1-5.Other] If desired, the resist composition according to this embodiment may further contain compatible additives, such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, or a dye.

[0148] [2. Pattern formation method] The pattern formation method according to this embodiment includes the steps of applying a resist composition to a substrate, exposing the resist film formed by the application step, and developing the exposed resist film.

[0149] [2-1. Coating process] The pattern forming method according to this embodiment includes a step of applying a resist composition to a substrate.

[0150] <Substrate> The substrate used in this embodiment is not particularly limited, and any known and commonly used substrate may be used. For example, a substrate for electronic components or a substrate on which a predetermined wiring pattern is formed may be used. The material of the substrate is not particularly limited, and examples thereof include substrates made of metals such as silicon wafers, copper, chromium, iron, and aluminum, and substrates made of inorganic substances such as glass, titanium oxide, and silicon dioxide. The size, shape, etc. of the substrate are not particularly limited, and the surface of the substrate may be smooth, curved, or uneven, or may be a thin plate-shaped substrate.

[0151] The surface of the substrate may be subjected to a surface treatment as necessary. In the case of a substrate having a hydroxyl group on the surface layer of the substrate, the surface of the substrate is treated with a silane coupling agent capable of reacting with the hydroxyl group, thereby changing the surface layer of the substrate from hydrophilic to hydrophobic, and thereby improving the adhesion between the substrate and the metal compound-containing film. Examples of the silane coupling agent include hexamethyldisilazane (HMDS) and the like.

[0152] <Application method> The method of applying the resist composition onto the substrate is not particularly limited, and any known and commonly used method can be used.As the application method, for example, the CVD method (chemical vapor deposition method) such as thermal CVD, plasma CVD, and photo CVD, and the PVD method (physical vapor deposition method) such as vacuum deposition, plasma-assisted deposition, sputtering, and ion plating can be used as the dry method.In addition, for example, the application method such as spin coating, bar coating, roll coating, flow coating, dip coating, spray coating, inkjet printing, and screen printing can be used as the wet method.

[0153] As a method for applying the resist composition according to this embodiment onto a substrate, from the viewpoint of forming a uniform film thickness, etc., a wet method such as spin coating or screen printing is preferably used, and spin coating is more preferably used.

[0154] The method for drying the resist film formed by applying the resist composition onto a substrate is not particularly limited, and can be performed using, for example, a heating device such as a hot plate (post-apply bake (PAB)), a pressure reducing device, or the like. The baking conditions are not particularly limited and can be appropriately set depending on the type of resist film, the application, etc. The baking temperature is preferably 80 to 350° C., more preferably 100 to 300° C., and even more preferably 120 to 250° C. The baking time is preferably 10 seconds to 10 minutes, more preferably 20 seconds to 5 minutes, and even more preferably 30 seconds to 200 seconds.

[0155] The thickness of the resist film after drying is not particularly limited, but is preferably from 0.5 to 100 nm, more preferably from 1 to 75 nm, and even more preferably from 1 to 60 nm.

[0156] [2-2. Exposure process] The pattern forming method according to this embodiment includes a step of exposing the resist film formed in the above-mentioned coating step.

[0157] As an exposure device in the exposure step of the resist film, for example, an ArF exposure device, an electron beam lithography device, an EUV exposure device, etc. In the exposure step, exposure may be performed through a mask (mask pattern) on which a predetermined pattern is formed, or selective exposure may be performed by lithography using direct irradiation with an electron beam without using a mask pattern.

[0158] The wavelength used for exposure is not particularly limited, and radiation such as ArF excimer laser (wavelength 193 nm), KrF excimer laser (248 nm), F2 excimer laser (wavelength 157 nm), EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, and soft X-rays may be used.

[0159] The exposure dose on the resist film is 1 to 100 mJ / cm in the case of an ArF excimer laser or a KrF excimer laser. 2 is preferably 20 to 60 mJ / cm 2 In the case of extreme ultraviolet rays, the exposure dose is preferably 500 mJ / cm. 2 It is preferable that the concentration is 0.1 to 200 mJ / cm or less. 2 More preferably, the concentration is 3 to 100 mJ / cm 2 In the case of electron beam, the exposure dose is 0.1 to 20 μC / cm 2 is preferably 3 to 10 μC / cm 2 It is more preferable that:

[0160] After the resist film is exposed to light, it may be baked (post-exposure bake (PEB)). The baking conditions are not particularly limited and can be appropriately set depending on the type of resist film, the application, etc. The baking temperature is preferably 80 to 350°C, more preferably 100 to 300°C, and even more preferably 120 to 250°C, using a heating device such as a hot plate. The baking time is preferably 10 seconds to 10 minutes, more preferably 20 seconds to 5 minutes, and even more preferably 30 seconds to 200 seconds.

[0161] [2-3. Development process] The pattern forming method according to the present embodiment includes a step of developing the exposed resist film. In the developing step, the exposed resist film is developed with a developer to form a pattern. After the development, the resist film may be washed with a rinse solution and then dried, and may be further baked in some cases.

[0162] <Developer> In the present embodiment, the developer used is an alkaline developer in the case of alkali development, and a developer containing an organic solvent in the case of solvent development.

[0163] Examples of the alkaline developer used in the case of alkaline development include alkaline developers containing at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide (TMAH), etc. Among these, the alkaline developer is preferably an aqueous TMAH solution, more preferably a 0.1 to 10 mass % TMAH solution, and even more preferably a 0.5 to 5 mass % TMAH solution.

[0164] Examples of the solvent developer used in the case of solvent development include developers containing one or more of polar solvents such as ketone-based solvents, ester-based solvents, alcohol-based solvents, nitrile-based solvents, amide-based solvents, and ether-based solvents, and organic solvents such as hydrocarbon-based solvents. Among these, the organic solvent used in the solvent developer is preferably a polar solvent, and more preferably a ketone-based solvent, an ester-based solvent, or a nitrile-based solvent.

[0165] Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, diacetone alcohol, 1-hydroxyacetone, acetophenone, methyl naphthyl ketone, and 2-heptanone.

[0166] Examples of ester-based solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl Pyrether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, propyl formate, butyl formate, lactic acid Examples of the lactate derivatives include ethyl, propyl lactate, butyl lactate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, and propyl 3-methoxypropionate.

[0167] Examples of nitrile solvents include acetonitrile, propionitrile, butyronitrile, and valeronitrile.

[0168] The method of developing the resist film exposed by using the developer is not particularly limited, and can use a known and commonly used method.The method of developing by using the developer can be, for example, the method of immersing the substrate having the resist film after exposure in the developer for a certain time (dip method), the method of spraying the developer on the surface of the resist film after exposure (spray method), the method of discharging the developer from a discharge nozzle at a certain speed toward the surface of the resist film after exposure on the substrate rotating at a certain speed (dynamic dispense method), etc.

[0169] <Rinse solution> After developing with the solvent developer, a step of washing with a rinse liquid may be included. The rinse liquid is not particularly limited, and any known and commonly used liquid may be used. As the rinse liquid, an organic solvent that does not easily dissolve the resist pattern may be appropriately selected from the organic solvents contained in the solvent developer.

[0170] The rinse liquid is not particularly limited, and may be, for example, at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents. Among these, it is preferable to use at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, and amide solvents as the rinse liquid, it is more preferable to use at least one solvent selected from the group consisting of alcohol solvents and ester solvents, and it is even more preferable to use at least one alcohol solvent.

[0171] The alcohol-based solvent used in the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be linear, branched, or cyclic. Specific examples of the monohydric alcohol include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. These organic solvents may be used alone or in combination of two or more.

[0172] The rinse solution may contain, in addition to the organic solvents described above, an organic solvent other than the above or water. When the rinse solution contains water, the content of water is preferably 30% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, and particularly preferably 3% by mass or less, based on the total amount of the rinse solution.

[0173] The method of cleaning the resist pattern with the rinse liquid is not particularly limited, and any known and commonly used method can be used. Examples of the method of cleaning with the rinse liquid include a method of immersing the resist pattern in the rinse liquid for a certain period of time (dip method), a method of spraying the rinse liquid on the surface of the resist pattern (spray method), and a method of discharging the rinse liquid from a discharge nozzle at a constant speed toward the surface of the resist pattern rotating at a constant speed (dynamic dispense method). EXAMPLES

[0174] The present invention will be specifically described below by showing examples, but the present invention is not limited to these examples.

[0175] [1. Synthesis of component (B)] <Synthesis Example 1: Hexakis(bis(2-trifluoromethylphenyl)phenylsulfonium)metangstate (B-1)> [ka]

[0176] 6.68 g of bis(2-trifluoromethylphenyl)phenylsulfonium chloride was dissolved in 99.36 g of pure water to obtain ammonium metatungstate (ammonium metatungstate hydrate ((NH4)6[H2W 12 O 40 6.88 g of ethyl acetate (HCl)·xH2O) was added and the reaction solution was stirred at room temperature for 30 minutes. The reaction solution was filtered and the resulting powder was dried under reduced pressure at room temperature for 18 hours. The dried powder was dissolved in 100 g of dimethylformamide, and 335 g of methanol was added. The target compound was obtained by crystallization at room temperature. 1 H-NMR (400MHz, DMSO-D6): δ(ppm)=5.97(s, 0.33H), 7.65-8.35(m, 13H). 183 W-NMR (20.84MHz, DMSO-D6): δ(ppm)=100.13(s, 12W). ESI-MS: NEGATIVE m / z 712.3 (median) ([H4W 12 O 40 ] 4- )

[0177] <Synthesis Example 2: Tris(phenylbis(2-(trifluoromethyl)phenyl)sulfonium)phosphotungstate (B-2)> [ka]

[0178] 27.95 g of phenylbis(2-(trifluoromethyl)phenyl)sulfonium chloride was dissolved in 50 g of cyclohexanone to obtain phosphotungstic acid (H3[PW 12 O 40 41.97 g of ethyl acetate (1,2-dichloromethane)·30H2O was added and the reaction solution was stirred at room temperature for 2 hours. The reaction solution was filtered and the obtained powder was dried under reduced pressure at room temperature for 18 hours. The dried powder was crystallized at room temperature using dichloromethane and acetonitrile to obtain the target compound. 1H-NMR(400MHz,DMSO-D6):δ(ppm)=7.63-8.36(m,39H). 183 W-NMR (20.84MHz, DMSO-D6): δ(ppm)=-86.7(s, 12W). ESI-MS:NEGATIVE m / z 959 (median) ([PW 12 O 40 ] 3- )

[0179] <Synthesis Example 3: Tetrakis(phenylbis(2-(trifluoromethyl)phenyl)sulfonium)silicate (B-3)> [ka]

[0180] 37.26 g of phenylbis(2-(trifluoromethyl)phenyl)sulfonium chloride was dissolved in 50 g of cyclohexanone to obtain tungstosilicic acid (H4[SiW 12 O 40 41.06 g of ethyl acetate (2H2O) was added and the reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was filtered and the resulting powder was dried under reduced pressure at room temperature for 18 hours. The dried powder was crystallized at room temperature using dichloromethane and acetonitrile to obtain the target compound. 1 H-NMR(400MHz,DMSO-D6):δ(ppm)=7.63-8.34(m,52H). 183 W-NMR (20.84MHz, DMSO-D6): δ(ppm)=-92.7(s12W). ESI-MS:NEGATIVE m / z 718.5 (median) ([SiW 12 O 40 ] 4- )

[0181] <Synthesis Example 4: Tris(bis(3.5-difluorophenyl)phenylsulfonium)phosphotungstate (B-4)> [ka]

[0182] 41.26 g of bis(3,5-difluorophenyl)phenylsulfonium chloride was dissolved in 50 g of cyclohexanone to obtain phosphotungstic acid (H3[PW 12 O 40 41.97 g of ethyl acetate (1,2-dichloromethane)·30H2O was added and the reaction solution was stirred at room temperature for 2 hours. The reaction solution was filtered and the obtained powder was dried under reduced pressure at room temperature for 18 hours. The dried powder was crystallized at room temperature using dichloromethane and acetonitrile to obtain the target compound. 1 H-NMR(400MHz,DMSO-D6):δ(ppm)=7.63-7.98(m,33H). 183 W-NMR(20.84MHz,DMSO-D6):δ(ppm)=-86.7(s,12W). ESI-MS:NEGATIVE m / z 959 (median) ([PW 12 O 40 ] 3- )

[0183] <Synthesis Example 5: Tris(bis(4-tert-butylphenyl)iodonium)phosphotungstate (B-5)> [ka]

[0184] 27.57 g of bis(4-tert-butylphenyl)iodonium chloride was dissolved in 50 g of cyclohexanone to obtain phosphotungstic acid (H3[PW 12 O 40 41.97 g of ethyl acetate (1,2-dichloromethane)·30H2O was added and the reaction solution was stirred at room temperature for 2 hours. The reaction solution was filtered and the obtained powder was dried under reduced pressure at room temperature for 18 hours. The dried powder was crystallized at room temperature using dichloromethane and acetonitrile to obtain the target compound. 1 H-NMR (400MHz, DMSO-D6): δ(ppm)=8.19(d,12H),7.51(d,12H),1.22(s,54H). 183 W-NMR(20.84MHz,DMSO-D6):δ(ppm)=-86.7(s,12W). ESI-MS:NEGATIVE m / z 959 (median) ([PW 12 O 40 ] 3- )

[0185] [2. Evaluation of Component (B) as an Acid Generator] [2-1. Preparation of test resist composition] Test resist compositions R1-1 to R1-6 were obtained by mixing components (A), (B), (C-1), and (C-2) in the amounts (units: parts by mass) shown in Table 1 below, and adjusting the solid content concentration of each test resist composition to 1.15% by mass using an organic solvent (S-1) (propylene glycol methyl ether acetate: dimethylformamide: ethyl lactate = 3: 17: 80). Test resist composition R1-7 was obtained by mixing components (A) and (B) in the amounts (units: parts by mass) shown in Table 1 below, and adjusting the solid content concentration of the test resist composition to 0.20% by mass using an organic solvent (S-2) (propylene glycol methyl ether acetate: cyclohexanone = 95: 5).

[0186] Details of the components (A), (C-1) and (C-2) in Table 1 are as follows. The components (B) were the polyacid salts B-1 to B-5 synthesized above. The amounts of each component are shown as solid contents. <Component (A)> A-1: A resin copolymerized with a structural unit (a1-1-1) having an acid dissociable group and a structural unit (a2-1-1) having a phenolic hydroxyl group, represented by the following formula (A-1) (the molar ratio of (a1-1-1) to (a2-1-1) is 60:40). The weight average molecular weight (Mw) calculated as standard polystyrene by GPC measurement is 7000. [ka] A-2: A resin copolymerized with a structural unit (a1-1-2) having an acid dissociable group, a structural unit (a3-1-1) having a lactone-containing alicyclic group, and a structural unit (a4-1-1) having a polar group-containing hydrocarbyl group, as shown in the following formula (A-2) (the molar ratio of (a1-1-2), (a3-1-1), and (a4-1-1) is 40:40:20). The Mw calculated based on standard polystyrene by GPC measurement is 10,000. [ka]

[0187] <(C-1) component> · C-1-1: An acid generator which is a salt of 2-((adamantane-1-carbonyl)oxy)-1,1-difluoroethane-1-sulfonic acid anion and phenylbis(2-(trifluoromethyl)phenyl)sulfonium cation, represented by the following formula (C-1-1). [ka]

[0188] <(C-2) component> C-2-1: An acid diffusion controller which is a salt of a salicylic acid anion and a phenylbis(2-(trifluoromethyl)phenyl)sulfonium cation, represented by the following formula (C-2-1). [ka]

[0189] [Table 1]

[0190] [2-2. Preparation of test film (KrF exposure device), development and its evaluation] <Preparation of test membrane> Test resist compositions R1-1 to R1-6 were applied onto an 8-inch silicon substrate treated with hexamethyldisilazane (HDMS) using a spinner (1500 rpm), and post-applied bake (PAB) treatment was performed on a hot plate at a temperature of 110°C for 60 seconds, followed by drying to form a resist film with a thickness of 25 nm. The average thickness of the formed resist film was measured using a film thickness measuring device (JA Woollam's "M-2000D").

[0191] The resist film was exposed to light by open frame exposure using a KrF exposure device (NIKON Corporation's "NSR-S203B", NA (numerical aperture) = 0.68, σ = 0.75) at an exposure dose of 0 mJ / cm 2 (unexposed), 5mJ / cm 2 , 10 mJ / cm 2 , 60mJ / cm 2 The exposure was carried out under different exposure conditions. After the exposure, a post-exposure bake (PEB) treatment was carried out at 100° C. for 60 seconds to prepare test films M1-1 to M1-6.

[0192] <Development of test film and its evaluation> Each of the test films was subjected to alkaline development for 60 seconds using a 2.38 mass % TMAH aqueous solution (product name "NMD-3": manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23° C. Then, it was rinsed for 15 seconds using pure water. The film thickness (average thickness) of each test film after development was measured using the film thickness measuring device described above, and the results shown in Table 2 were obtained.

[0193] [Table 2]

[0194] From Table 2, it can be seen that, compared with the case where C-1-1 is used as the acid generator, when component (B), which generates a slightly weaker acid, is used as the acid generator, a greater amount of exposure is required to change the solubility of component (A) in the developer. It is also known that the pKa values ​​of component (B) generally follow the order of phosphotungstic acid < silicotungstic acid < metatungstic acid. Compared with M1-3, M1-5, and M1-6, which contain an acid generator in which the anion moiety of component (B) is a phosphotungstic acid anion, M1-4, which contains an acid generator in which the anion moiety of component (B) is a silicotungstic acid anion, and M1-2, which contains an acid generator in which the anion moiety of component (B) is a metatungstic acid anion, it is understood that a greater amount of exposure is required to change the solubility of component (A) in the developer. Furthermore, by changing the cationic portion of component (B) to phenylbis(2-(trifluoromethyl)phenyl)sulfonium, bis(3,5-difluorophenyl)phenylsulfonium, or bis(4-tert-butylphenyl)iodonium, as in M1-3, M1-5, and M1-6, or by changing the type of onium cation or the substituents on the onium cation, such as electron-withdrawing groups or electron-donating groups, it is possible to fine-tune the exposure dose required to change the solubility of component (A) in the developer.

[0195] For this reason, the results in Table 2 show that the acid strength, sensitivity such as the exposure dose required to change the solubility of component (A) in a developer, and even resolution can be appropriately adjusted by adjusting the combination of the anion and cation moieties in component (B). [2-3. Preparation of test film (ArF exposure device), development and its evaluation] <Preparation of test membrane> An organic anti-reflective coating material was applied onto a 12-inch silicon substrate using a spinner, and heat-treated on a hot plate at 205°C for 60 seconds to form an anti-reflective coating with a thickness of 85 nm. Then, test resist composition R1-7 was applied using a spinner (1500 rpm), and post-applied bake (PAB) treatment was performed on a hot plate at 110°C for 60 seconds, and the substrate was dried to form a resist film with a thickness of 100 nm. The average thickness of the formed resist film was measured using a film thickness measuring device (JA Woollam's "M-2000D"). The resist film was exposed to light using an ArF exposure device (NIKON CORPORATION's "NSR-S-308F", NA (numerical aperture) = 0.92, σ = 0.95). After exposure, a post-exposure bake (PEB) treatment was carried out at 130° C. for 60 seconds.

[0196] <Development of test film and its evaluation> Each of the test films was subjected to alkaline development for 60 seconds using a 2.38 mass % TMAH aqueous solution (product name "NMD-3": manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23° C. Then, it was rinsed for 15 seconds using pure water. The dimensions of the substrate were measured using a Hitachi High-Technologies Corporation CG-5000 electron microscope, and the irradiation energy was 40 mJ / cm 2 It was confirmed that a 100 nm line and space pattern was resolved at an exposure dose of 1. From the above, it was confirmed that the component (B) according to the present invention functions as an acid generator by itself.

[0197] [3. Evaluation of Component (B) as an Acid Diffusion Controller] [3-1. Preparation of test resist composition] The test resist compositions R2-1 to R2-6 were prepared by blending the components (A), (B), and (C-1) in the amounts (units: parts by mass) shown in Table 3 below, and using an organic solvent (S-1) (propylene glycol methyl ether acetate:dimethylformamide:ethyl lactate=3:17:80) the solids concentration of each test resist composition was adjusted to 1.15 mass%.

[0198] The details of the components (A), (B) and (C-1) in Table 3 are as described above. The amount of each component is shown as a solid content value.

[0199] [Table 3]

[0200] [3-2. Preparation of test membrane] Test films M2-1 to M2-6 were produced by the same method as described above using the test resist compositions R2-1 to R2-6.

[0201] [3-3. Development and evaluation of test films] Each of the test films was subjected to alkaline development for 60 seconds using a 2.38 mass % TMAH aqueous solution (product name "NMD-3": manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23° C. Then, it was rinsed for 15 seconds using pure water. The film thickness (average thickness) of each test film after development was measured using the film thickness measuring device described above, and the results shown in Table 4 were obtained.

[0202] [Table 4]

[0203] Comparing the results for M1-1 in Table 2 with the results for M2-1 in Table 4, it can be seen that, compared to M1-1, which contains the acid generator C-1-1 as well as the acid diffusion controller C-2-1, M2-1, which contains the acid generator C-1-1 but does not contain the acid diffusion controller C-2-1, experiences a change in the solubility of component (A) in the developer at a smaller exposure dose. In contrast, as shown in Table 4, by incorporating a specified amount of component (B), as can be seen from the results for M2-2 to M2-6 in Table 4, a greater amount of exposure is required to change the solubility of component (A) in the developer compared to the case of M2-1, and the diffusion of the acid generated from the acid generator C-1-1 is controlled. Therefore, from the results in Table 4, it is evident that the above component (B) can also be used effectively as an acid diffusion controller.

[0204] As mentioned above, it is generally known that the order of pKa values ​​is phosphotungstic acid < silicotungstic acid < metatungstic acid. And, compared with M2-3, M2-5 and M2-6, which contain an acid generator in which the anion part of the (B) component is phosphotungstic acid anion, M2-2, which contains an acid generator in which the anion part of the (B) component is metatungstic acid anion, and M2-4, which contains an acid generator in which the anion part of the (B) component is silicotungstic acid anion, it is found that a larger amount of exposure is required to change the solubility of the (A) component in the developer. This is considered to be due to the fact that metatungstic acid anion or silicotungstic acid anion, which have a larger pKa value, have a higher ability to retain protons than phosphotungstic acid anion. Furthermore, it was found that the exposure dose required to change the solubility of component (A) in the developer can be finely adjusted by changing the type of onium cation and the substituents on the onium cation, such as electron-withdrawing groups and electron-donating groups, to phenylbis(2-(trifluoromethyl)phenyl)sulfonium, bis(3,5-difluorophenyl)phenylsulfonium, and bis(4-tert-butylphenyl)iodonium, as in M2-3, M2-5, and M2-6. This is thought to be due to the fact that, when component (B) functions as an acid diffusion controller, an equilibrium state is formed depending on which of the cationic moiety of component (B) and the proton is more likely to bind to the anionic moiety of component (B).

[0205] For this reason, the results in Table 4 show that the strength of component (B) as an acid diffusion controller, the sensitivity such as the exposure dose required to change the solubility of component (A) in a developer, and even the resolution can be appropriately fine-tuned by adjusting the combination of the anion and cation moieties of component (B).

Claims

1. (A) Resin components whose solubility in the developer changes due to the action of acid, (B) Polysate and A resist composition containing the following:

2. The resist composition according to claim 1, wherein the anionic portion of the (B) polyate is a polyoxomolybdate anion, a polyoxotungstate anion, a polyoxoniobate anion, or a polyoxotantalate anion.

3. The resist composition according to claim 1, wherein the cation portion of the (B) polyate is an organic sulfonium cation, an organic iodonium cation, or an organic quaternary ammonium cation.

4. The resist composition according to claim 1, wherein the (B) polyate is a salt of a polyoxomolybdate anion, polyoxotungstate anion, polyoxoniobate anion, or polyoxotantalate anion with an organic sulfonium cation, organic iodonium cation, or organic quaternary ammonium cation.

5. The resist composition according to claim 1, further comprising (C) an acid generator or an acid diffusion control agent.

6. A step of forming a resist film by applying the resist composition according to any one of claims 1 to 5 onto a substrate, The steps include: exposing the resist film, A step of developing the exposed resist film with a developer, A pattern forming method having the following characteristics.

7. The resist composition according to claim 1, wherein the resin component whose solubility in the developer changes due to the action of the acid (A) contains an acid-dissociable group.

8. The resin component whose solubility in the developer changes due to the action of the acid (A) comprises a structural unit (a1) having an acid-dissociable group, The aforementioned structural unit (a1) having an acid-dissociable group is a structural unit represented by the following formula (a1-1) or (a1-2). The resist composition according to claim 1. 【Chemistry 1】 [In the formula, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group; L a1 represents a single bond, -O-, -C(=O)-, -C(=O)O-, -OCO-, -CONH-, NHCO-, -S-, or -SO2-; Ar a1 represents a C6-18 arylene group which may have substituents; G represents an acid-dissociating group.

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