Resist composition and method for producing resist pattern

Abstract

To provide a resist composition excellent in resolution and capable of producing a resist pattern having a good shape and resistance to cracking.SOLUTION: And a structural unit represented by the formula (a2), wherein the structural unit represented by the formula (a1) includes a structural unit represented by the formula (a1) and a structural unit represented by the formula (a2), and the structural unit represented by the formula (a1) does not include a structural unit represented by the formula (a2) and a structural unit represented by the formula (a1), and the structural unit represented by the formula (b1) does not include a structural unit represented by the formula (LA).SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Patent Document 1 describes a resist composition containing a resin in which the phenolic hydroxyl groups of polyhydroxystyrene are protected, and a resin that contains an acid labile group but does not have an aromatic hydrocarbon group. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-21470 Summary of the Invention [Problem to be solved by the invention]

[0004] When a thick-film resist pattern of 5 μm or greater was prepared using a resist composition as described in Patent Document 1, which contained a resin containing a structural unit represented by formula (a2-2) and a structural unit represented by formula (a1-1), but not containing a structural unit represented by formula (a1-2) or a structural unit represented by formula (a2-1), and a resin containing a structural unit represented by formula (a2-1) and a structural unit represented by formula (a1-2), but not containing a structural unit represented by formula (a1-1), and which contained a triphenylsulfonium cation as an acid generator, the resolution after development was insufficient and resist residues were sometimes generated. Therefore, an object of the present invention is to provide a resist composition that is capable of forming a resist pattern with excellent resolution. [Means for solving the problem]

[0005] The present invention includes the following inventions. [1] A resist composition comprising a resin (A) containing a structural unit having an acid labile group, and an acid generator (B) represented by formula (b1), wherein the resin (A) comprises a resin (A1) and a resin (A2). Resin (A1): A resin containing a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-2), but not containing a structural unit represented by formula (a1-2) or a structural unit represented by formula (a2-1). Resin (A2): A resin containing a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-1), but not containing a structural unit represented by formula (a1-2). TIFF2026013351000001.tif2877[In formula (b1), R b1 represents a hydroxy group or a hydrocarbon group having 1 to 12 carbon atoms, and -CH2- contained in the hydrocarbon group may be replaced by -O- or -CO-. Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. The -CH2- contained in the ring constituting the cation may be replaced by -O-, -S- or -CO-. nb1 represents an integer of 0 to 3. When nb1 is 2 or more, a plurality of R b1 may be the same or different. nb2 represents an integer of 1 to 3. A - represents a sulfonate anion. TIFF2026013351000002.tif5171[In formula (a2-2), R a21 represents a hydrogen atom or a methyl group. L a21 is -O- or *-O-(CH2) k01 represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R a22 represents a hydroxy group or a carboxy group. R a23 , and R a24each independently represents a hydrogen atom, a methyl group, a hydroxy group, or a carboxy group. TIFF2026013351000003.tif49100 [In formula (a1-1) and formula (a1-2), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R a1 and R a2 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R a3 represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms. R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a1’ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a2’ and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom and oxygen atom to which they are bonded. -CH2- contained in the hydrocarbon group having 1 to 20 carbon atoms and the heterocyclic ring having 3 to 20 carbon atoms may be replaced with -O- or -S-. L a01 is -O- or *-O-(CH2) k01 represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 represents an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. m represents an integer of 0 to 4. When m is 2 or more, a plurality of R a6 may be the same or different from each other. TIFF2026013351000004.tif3677[In formula (a2-1), Ra7 represents a hydrogen atom or a methyl group. R a10 represents a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. m' represents an integer of 0 to 4. When m' is 2 or more, a plurality of R a10 may be the same or different from each other. m'' represents an integer of 1 to 4. However, the sum of m' and m'' is 5 or less. [2] A in equation (b1) - The resist composition according to [1], wherein the compound is represented by formula (bA). TIFF2026013351000005.tif2763[In formula (bA), Q 1 and Q 2 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. L b1 represents a saturated hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. Y b1 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent. -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. bA1 represents an integer of 1 to 6. When bA1 is 2 or greater, the groups in the parentheses may be the same or different.] [3] The resist composition according to [1] or [2], wherein the content of the resin (A1) is 40% by mass or more and 80% by mass or less based on the total amount of the resins. [4] A method for producing a resist pattern, comprising: (1) A step of applying the resist composition according to any one of [1] to [3] onto a substrate; (2) drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A manufacturing method including a step of developing the composition layer after heating. [Effects of the Invention]

[0006] By using the resist composition of the present invention, it is possible to form a resist pattern with excellent resolution and with high precision. Furthermore, by using the resist composition of the present invention, it is possible to form a pattern with excellent shape and crack resistance. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a diagram schematically illustrating a pattern shape of a trench pattern of a resist pattern. DETAILED DESCRIPTION OF THE INVENTION

[0008] In this specification, unless otherwise specified, in the explanation of the structural formula of a compound, "aliphatic hydrocarbon group" means a straight-chain or branched aliphatic hydrocarbon group, "alicyclic hydrocarbon group" means a group in which the number of hydrogen atoms corresponding to the valence is removed from an alicyclic hydrocarbon ring. "Aromatic hydrocarbon group" also includes groups in which a hydrocarbon group is bonded to an aromatic ring. When stereoisomers exist, all stereoisomers are included. In this specification, "(meth)acrylic acid" means "at least one of acrylic acid and methacrylic acid," and "(meth)acrylate" means "at least one of acrylate and methacrylate." In the groups described herein, those that can have both a linear structure and a branched structure are interpreted as including both. When -CH2- contained in a hydrocarbon group or the like is replaced with -O- or the like, the same example applies to each group, and the number of carbon atoms before the replacement is the number of carbon atoms in the hydrocarbon group or the like. A "combined group" means a group in which two or more of the exemplified groups are bonded, and the valence of these groups may be changed appropriately depending on the bonding form. "Derived from" or "derived from" means that a polymerizable C=C bond contained in the molecule becomes a -CC- group (single bond) by polymerization. The number of carbon atoms in a substituent is not included in the number of carbon atoms in the substituted group. In this specification, the term "solid content of the resist composition" refers to the sum of all components in the resist composition excluding the solvent (E), which will be described later.

[0009] 1. Resist composition The resist composition of the present invention contains a resin containing a structural unit having an acid labile group (hereinafter, sometimes referred to as "resin (A)") and an acid generator represented by formula (b1) (hereinafter, sometimes referred to as "acid generator (B)"). Resin (A) includes a resin (hereinafter sometimes referred to as "resin (A1)") that contains a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-2) but does not contain a structural unit represented by formula (a1-2) or a structural unit represented by formula (a2-1), and a resin (hereinafter sometimes referred to as "resin (A2)") that contains a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-1) but does not contain a structural unit represented by formula (a1-2). In addition to the resin (A1), the resin (A2), and the acid generator (B), the resist composition of the present invention preferably further contains a quencher (hereinafter sometimes referred to as "quencher (C)") and / or a solvent (hereinafter sometimes referred to as "solvent (E)").

[0010] <Resin (A)> The resin (A) contains a structural unit having an acid labile group (hereinafter, sometimes referred to as "structural unit (a1)"). The acid labile group refers to a group containing a group (sometimes referred to as a leaving group) that can be eliminated upon contact with an acid (e.g., trifluoromethanesulfonic acid, etc.). When the resin (A) comes into contact with an acid, the leaving group is eliminated from the acid labile group, forming a hydrophilic group (e.g., a hydroxy group (e.g., a phenolic hydroxy group) or a carboxy group). The solubility of the resin (A) in an alkaline aqueous solution increases upon contact with an acid. In other words, the resin (A) is preferably insoluble or slightly soluble in an alkaline aqueous solution before contact with an acid, but becomes soluble in an alkaline aqueous solution after contact with an acid. Examples of acids that eliminate the leaving group contained in the acid labile group include carboxylic acids and sulfonic acids. In the composition of the present invention, examples include carboxylic acid compounds and sulfonic acid compounds that are generated by irradiating (exposing) the acid generator (B) described below with light in the photolithography process. Resin (A) may contain, in addition to a structural unit having an acid labile group, structural units known in the art, such as a structural unit not having an acid labile group (hereinafter sometimes referred to as "structural unit (a2)"), as long as it has the above-mentioned properties.

[0011] Examples of the acid labile group include a group represented by formula (10) and a group represented by formula (20). TIFF2026013351000006.tif24168[In formula (10), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group combining these, or R a1 and R a2 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R a3 represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group combining these. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bond.] TIFF2026013351000007.tif26170[In formula (20), R a1’ and R a2’each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a1’ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a2’ and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X. A methylene group contained in the hydrocarbon group having 1 to 20 carbon atoms and the heterocyclic ring having 3 to 20 carbon atoms may be replaced with an oxygen atom or a sulfur atom. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. * represents a bond.]

[0012] R expressed by equation (10) a1 ~R a3 The alkyl group having 1 to 8 carbon atoms may be either linear or branched, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. a1 ~R a3 The alkyl group having 1 to 8 carbon atoms preferably has 1 to 6 carbon atoms, and more preferably has 1 to 4 carbon atoms. R a1 ~R a3 The alicyclic hydrocarbon group having 3 to 20 carbon atoms may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bond): TIFF2026013351000008.tif10150R a1 ~R a3 The alicyclic hydrocarbon group having 3 to 20 carbon atoms preferably has 3 to 18 carbon atoms, more preferably has 3 to 16 carbon atoms, and even more preferably has 3 to 12 carbon atoms. Examples of the group combining an alkyl group and an alicyclic hydrocarbon group include alkylcycloalkyl groups or cycloalkylalkyl groups such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an isobornyl group, an adamantylmethyl group, an adamantyldimethyl group, and a norbornylethyl group.

[0013] R a1 and R a2 -C(R a1 )(R a2 )(R a3 ) includes, for example, the following groups. The ring having 3 to 20 carbon atoms preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. * represents a bond to -O-. TIFF2026013351000009.tif30138R a1 is an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R a2 and form a ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded, and is preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or R a2 and more preferably bonded to form a ring having 3 to 12 carbon atoms together with the carbon atoms to which they are bonded. R a2 is an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R a1 and form a ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded, and is preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or R a1 and more preferably bonded to form a ring having 3 to 12 carbon atoms together with the carbon atoms to which they are bonded. R a3 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms. ma is preferably 0. na is preferably 1. Examples of the group represented by formula (10) include R a1 , R a2 and R a3 are each independently an alkyl group having 1 to 3 carbon atoms (preferably a tert-butoxycarbonyl group); R a1 and R a2 are each independently an alkyl group having 1 to 3 carbon atoms, and R a3 is a cyclopentyl group or a cyclohexyl group; R a1 and R a2 are bonded to each other to form a cyclopentane ring or a cyclohexane ring together with the carbon atoms to which they are attached, and R a3 is an alkyl group having 1 to 3 carbon atoms. Specific examples of the group represented by formula (10) include the following groups. TIFF2026013351000010.tif96162

[0014] R of the group represented by formula (20) a1’ ~R a3’ Examples of the hydrocarbon group having 1 to 20 carbon atoms include chain hydrocarbon groups having 1 to 20 carbon atoms (such as alkyl groups, alkenyl groups, and alkynyl groups), alicyclic hydrocarbon groups having 3 to 20 carbon atoms, and aromatic hydrocarbon groups having 6 to 20 carbon atoms, as well as groups having 4 to 20 carbon atoms that are combinations of these. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, and a dodecyl group. Examples of the alkenyl group having 2 to 20 carbon atoms include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. Examples of the alkynyl group having 2 to 20 carbon atoms include an ethynyl group, a propynyl group, an isopropynyl group, a butynyl group, an isobutynyl group, a tert-butynyl group, a pentynyl group, a hexynyl group, an octynyl group, and a nonynyl group. The chain hydrocarbon group having 1 to 20 carbon atoms preferably has 1 to 18 carbon atoms, more preferably has 1 to 16 carbon atoms, even more preferably has 1 to 12 carbon atoms, still more preferably has 1 to 8 carbon atoms, and even more preferably has 1 to 6 carbon atoms. Examples of the alicyclic hydrocarbon group having 3 to 20 carbon atoms include monocyclic alicyclic hydrocarbon groups such as cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl, and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl, adamantyl, and norbornyl. The alicyclic hydrocarbon group having 3 to 20 carbon atoms preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. Examples of aromatic hydrocarbon groups having 6 to 20 carbon atoms include aryl groups such as phenyl, naphthyl, anthryl, biphenyl, and phenanthryl. The aromatic hydrocarbon group may further have a substituent, and examples of the substituent include an aryloxy group having 6 to 10 carbon atoms. The aromatic hydrocarbon group having 6 to 20 carbon atoms preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Among the groups having 4 to 20 carbon atoms in which the above groups are combined, examples of the group in which an alkyl group and an alicyclic hydrocarbon group are combined (groups having 4 to 20 carbon atoms) include a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, an isobornyl group, a 2-alkyladamantan-2-yl group, and a 1-(adamantan-1-yl)alkane-1-yl group. Examples of the group in which an alkyl group and an aromatic hydrocarbon group are combined (groups having 7 to 20 carbon atoms) include an aralkyl group and an aromatic hydrocarbon group having an alkyl group, and specific examples thereof include a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, a naphthylethyl group, a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of groups in which an alicyclic hydrocarbon group and an aromatic hydrocarbon group are combined (groups having 9 to 20 carbon atoms) include aromatic hydrocarbon groups having an alicyclic hydrocarbon group and alicyclic hydrocarbon groups having an aromatic hydrocarbon group, and specific examples include a p-cyclohexylphenyl group, a p-adamantylphenyl group, and a phenylcyclohexyl group. R a2’ and R a3’ When they are bonded to each other to form a heterocycle having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-XR a3’ Examples of such heterocyclic rings include the following groups: The heterocyclic ring having 3 to 20 carbon atoms preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. * represents a bond. TIFF2026013351000011.tif20170R a1’ is preferably a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and even more preferably a hydrogen atom. R a2' is a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, or R a3’ and form a heterocyclic ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded and X, and is preferably a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, or R a3’and more preferably bonded to the carbon atom to which they are bonded and X to form a heterocyclic ring having 3 to 12 carbon atoms, even more preferably a hydrocarbon group having 1 to 12 carbon atoms, and even more preferably a methyl group or an ethyl group. R a3’ is a hydrocarbon group having 1 to 18 carbon atoms, or R a2' and form a heterocyclic ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded and X, and is preferably a hydrocarbon group having 1 to 12 carbon atoms or R a2’ and more preferably bonded to form a heterocyclic ring having 3 to 12 carbon atoms together with the carbon atom to which they are bonded and X. Examples of the hydrocarbon group include alkyl groups having 1 to 18 carbon atoms, alicyclic hydrocarbon groups having 3 to 18 carbon atoms, aromatic hydrocarbon groups having 6 to 18 carbon atoms, and groups having a combination of these having 4 to 18 carbon atoms. These groups can be arbitrarily selected from the groups listed above. X is preferably an oxygen atom. na' is preferably 0.

[0015] Specific examples of the group represented by formula (20) include the following groups. TIFF2026013351000012.tif99170

[0016] Specific examples of the group represented by formula (10) include a group represented by formula (1) and a group represented by formula (1'). TIFF2026013351000013.tif4581 [In formula (1) and formula (1′), all symbols have the same meanings as defined above.] Specific examples of the group represented by formula (20) include a group represented by formula (2) and a group represented by formula (2'). TIFF2026013351000014.tif49150 [In formula (2), formula (2'), formula (2'') and formula (2'''), all symbols have the same meanings as defined above.]

[0017] <Structural unit (a1)> The resin (A) containing the structural unit (a1) can be produced, for example, by polymerizing a monomer component containing an ethylenically unsaturated compound that leads to the structural unit (a1). The acid labile group contained in the structural unit (a1) is preferably a group represented by the above formula (10) and / or a group represented by the above formula (20). The resin (A) may have only one type of structural unit (a1), or may have multiple types. As the structural unit (a1), a structural unit represented by formula (a1-1) (hereinafter sometimes referred to as "structural unit (a1-1)") and a structural unit represented by formula (a1-2) (hereinafter sometimes referred to as "structural unit (a1-2)") are preferred. TIFF2026013351000015.tif49100 [In formula (a1-1) and formula (a1-2), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R a1 and R a2 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R a3 represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms. R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a1’ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R a2’ and R a3’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom and oxygen atom to which they are bonded. The methylene groups contained in the hydrocarbon group having 1 to 20 carbon atoms and the heterocyclic ring having 3 to 20 carbon atoms may be replaced with oxygen atoms or sulfur atoms. L a01 is -O- or *-O-(CH2) k01 represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. Ra4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 represents an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. m represents an integer of 0 to 4. When m is 2 or more, a plurality of R a6 may be the same or different from each other.

[0018] In formula (a1-1), R a4 is preferably a methyl group. R a1 is an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R a2 and form a ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded, and is preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or R a2 and more preferably bonded to form a ring having 3 to 12 carbon atoms together with the carbon atoms to which they are bonded. R a2 is an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or R a1 and form a ring having 3 to 18 carbon atoms together with the carbon atom to which they are bonded, and is preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or R a1 and more preferably bonded to form a ring having 3 to 12 carbon atoms together with the carbon atoms to which they are bonded. R a3 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms. L a01 is preferably an oxygen atom or —O—(CH2) k01 It is —CO—O— (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. In formula (a1-2), R a5is preferably a hydrogen atom. R a1’ is preferably a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and even more preferably a hydrogen atom. R a2' is a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, or R a3’ and form a heterocyclic ring having 3 to 18 carbon atoms together with the carbon atom and oxygen atom to which they are bonded, and is preferably a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, or R a3’ and more preferably bonded to form a heterocyclic ring having 3 to 12 carbon atoms together with the carbon atom and oxygen atom to which they are bonded, further preferably a hydrocarbon group having 1 to 12 carbon atoms, and even more preferably a methyl group or an ethyl group. R a3’ is a hydrocarbon group having 1 to 18 carbon atoms, or R a2' and form a heterocyclic ring having 3 to 18 carbon atoms together with the carbon atom and oxygen atom to which they are bonded, and is preferably a hydrocarbon group having 1 to 12 carbon atoms or R a2’ and more preferably bonded to form a heterocyclic ring having 3 to 12 carbon atoms together with the carbon atom and oxygen atom to which they are bonded. Examples of the hydrocarbon group include alkyl groups having 1 to 18 carbon atoms, alicyclic hydrocarbon groups having 3 to 18 carbon atoms, aromatic hydrocarbon groups having 6 to 18 carbon atoms, and groups having 4 to 18 carbon atoms, which are combinations of these. These groups can be arbitrarily selected from the above-listed groups. The hydrocarbon group is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. The alkyl group and the alicyclic hydrocarbon group are preferably unsubstituted. When the aromatic hydrocarbon group has a substituent, the substituent is preferably an aryloxy group having 6 to 10 carbon atoms. R a6Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. The alkyl group having 1 to 6 carbon atoms is preferably an alkyl group having 1 to 4 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. R a6 Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, etc. The alkoxy group having 1 to 6 carbon atoms is preferably an alkoxy group having 1 to 4 carbon atoms, and more preferably an alkoxy group having 1 to 3 carbon atoms. R a6 is preferably an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, even more preferably a methyl group, an ethyl group, a methoxy group or an ethoxy group, and even more preferably a methyl group or a methoxy group. m is preferably 0 to 2, more preferably 0 or 1, and even more preferably 0. In formula (a1-2), -OC(R a1’ )(R a2’ )-OR a3’ is preferably bonded to the 3- or 4-position of the benzene ring (m- or p-position relative to the main chain bonded to the benzene ring), and more preferably bonded to the 4-position (p-position) of the benzene ring.

[0019] Examples of the structural unit (a1-1) include structural units represented by any one of formulas (a1-1-1) to (a1-1-18). In the following structural units, R a4 and R a5 Specific examples of the structural unit (a1-1) include structural units in which a hydrogen atom or a methyl group corresponding to the following is replaced with a methyl group or a hydrogen atom: TIFF2026013351000016.tif97156

[0020] Examples of the structural unit (a1-2) include structural units represented by any one of formulas (a1-2-1) to (a1-2-22). In the following structural units, R a5 A specific example of the structural unit (a1-2) is a structural unit in which the hydrogen atom corresponding to the following is replaced with a methyl group: The structural unit (a1-2) is preferably a structural unit represented by formula (a1-2-2), (a1-2-3), (a1-2-4), (a1-2-9) or (a1-2-14), and more preferably a structural unit represented by formula (a1-2-2), (a1-2-3), (a1-2-4) or (a1-2-9). TIFF2026013351000017.tif70163

[0021] TIFF2026013351000018.tif54152

[0022] The resin (A) includes a resin (A1) and a resin (A2). The resin (A1) and the resin (A2) contain the structural unit (a1-1) as the structural unit (a1) having an acid labile group, but do not contain the structural unit (a1-2). The total content of the structural units (a1) having an acid labile group in the resin (A1) is preferably 5 to 99 mol %, more preferably 10 to 95 mol %, even more preferably 15 to 90 mol %, still more preferably 20 to 85 mol %, and even more preferably 25 to 80 mol %, based on all structural units in the resin (A1). The total content of the structural units (a1) having an acid labile group in the resin (A2) is preferably 3 to 80 mol %, more preferably 5 to 60 mol %, even more preferably 10 to 55 mol %, still more preferably 15 to 50 mol %, and even more preferably 20 to 45 mol %, based on all structural units in the resin (A1). Here, not containing the structural unit (a1-2) means that a monomer that derives the structural unit (a1-2) is not used when synthesizing the resin (A1) and the resin (A2). Specifically, the amount of the structural unit (a1-2) is 1 mol % or less, preferably 0.5 mol % or less, and more preferably 0 mol %, based on the total structural units of the resin (A1) or the resin (A2).

[0023] <Structural unit (s) not having an acid labile group> The resin (A) may contain a structural unit (a1) having an acid labile group and, if necessary, a structural unit (s) not having an acid labile group (hereinafter sometimes referred to as "structural unit (s)"). The structural unit (s) preferably has a hydroxy group, a carboxy group, or a lactone ring. The use of a resin containing a structural unit having a hydroxy group or a carboxy group but no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring but no acid labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention can improve the resolution of the resist pattern and the adhesion to the substrate. The resin (A) may contain only one type of structural unit (s) that does not have an acid labile group, or may contain multiple types.

[0024] <Structural unit (a2)> The structural unit (a2) has an alcoholic hydroxy group, a phenolic hydroxy group, or a carboxy group. As the structural unit (a2), a structural unit represented by formula (a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)") and a structural unit represented by formula (a2-2) (hereinafter sometimes referred to as "structural unit (a2-2)") are preferred. TIFF2026013351000019.tif5182 [In formula (a2-1) and formula (a2-2), R a7 , R a21 each independently represents a hydrogen atom or a methyl group. R a10 represents a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. m' represents an integer of 0 to 4. When m' is 2 or more, a plurality of R a10 may be the same or different from each other. m'' represents an integer of 1 to 4. However, the sum of m' and m'' is 5 or less. L a21 is -O- or *-O-(CH2) k01 represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R a22 represents a hydroxy group or a carboxy group. R a23 , R a24 represents a hydrogen atom, a methyl group, a hydroxy group, or a carboxy group. R a10 Examples of the alkyl group having 1 to 6 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group having 1 to 6 carbon atoms preferably has 1 to 4 carbon atoms, and more preferably has 1 to 3 carbon atoms. R a10 Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, etc. The alkoxy group having 1 to 6 carbon atoms preferably has 1 to 4 carbon atoms, and more preferably has 1 to 3 carbon atoms. L a21 is preferably an oxygen atom, -O- or -O-CH2-CO-O-, and more preferably an oxygen atom. R a7 is preferably a hydrogen atom. R a21 is preferably a methyl group. R a23 , R a24 is preferably a hydrogen atom or a hydroxy group.

[0025] Examples of the structural unit (a2-1) include the following structural units. Among them, structural units represented by formula (a2-1-1), formula (a2-1-2), formula (a2-1-3), or formula (a2-1-4) are preferred. Monomers from which the structural unit (a2-1) is derived are described, for example, in JP-A-2010-204634. TIFF2026013351000020.tif63156

[0026] Examples of the structural unit (a2-2) include structural units derived from monomers described in JP-A No. 2010-204646. Of these, structural units represented by any one of formulae (a2-2-1) to (a2-2-9) are preferred. TIFF2026013351000021.tif87146 Resin (A1) does not contain the structural unit (a2-1) as the structural unit (a2), but Resin (A2) does. The content of the structural unit (a2-1) in Resin (A2) is preferably 5 to 99 mol%, more preferably 10 to 95 mol%, even more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, and even more preferably 25 to 80 mol%, based on all structural units in Resin (A2). The structural unit (a2-2) is contained in the resin (A1) and may also be contained in the resin (A2). The content of the structural unit (a2-2) in the resin (A1) and the resin (A2) is preferably 1 to 50 mol %, more preferably 2 to 45 mol %, still more preferably 3 to 40 mol %, still more preferably 4 to 35 mol %, and still more preferably 5 to 30 mol %, based on the total structural units of each resin.

[0027] <Structural unit (a3)> The lactone ring contained in the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valeractone ring, or a condensed ring of a monocyclic lactone ring with another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring (for example, a structural unit represented by formula (a3-2)). The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3), or formula (a3-4). One of these may be contained alone, or two or more may be contained. TIFF2026013351000022.tif51164 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6are each independently -O- or -O-(CH2) k3 It represents a group represented by —CO—O— (k3 represents an integer of 1 to 7). L a7 -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates the bonding site with the carbonyl group. R a18 , R a19 , R a20 and R a24 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other.

[0028] R a21 , R a22 , Ra23 and R a25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom in the formula include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group, and preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group having a halogen atom in the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or -O-(CH2)k3 In -CO-O-, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and even more preferably an oxygen atom. R a18 ~R a21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1. In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH 2 —CO—O— or —O—C 2 H 4 —CO—O—. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, as the structural unit represented by formula (a3-4), a structural unit represented by formula (a3-4)' is preferred. TIFF2026013351000023.tif4051 (in the formula, R a24 and L a7 has the same meaning as above.)

[0029] Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural units, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom is preferred. TIFF2026013351000024.tif108164 When resin (A1) and resin (A2) each contain structural unit (a3), the content of structural unit (a3) ​​in resin (A1) and resin (A2) is preferably 5 to 70 mol %, more preferably 5 to 60 mol %, even more preferably 5 to 50 mol %, and still more preferably 5 to 40 mol %, based on the total structural units of each resin.

[0030] <Structural unit (a4)> The resin (A) may have a structural unit other than those described above (hereinafter, sometimes referred to as "structural unit (a4)"). Examples of monomers that can be used to derive the structural unit (a4) include acrylates having a non-leaving hydrocarbon group. Examples of non-leaving hydrocarbon groups include groups having a linear, branched, or cyclic hydrocarbon group. Of these, the structural unit (a4) is preferably a group having an alicyclic hydrocarbon group. Examples of the structural unit (a4) include a structural unit represented by formula (a4-1). TIFF2026013351000025.tif3766[In formula (a4-1), R 51 represents a hydrogen atom or a methyl group. R 52represents a chain hydrocarbon group having 1 to 20 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group or the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.] The chain hydrocarbon group may be a linear or branched alkyl group having 1 to 20 carbon atoms, and R a1’ ~R a3’ Examples include the same as those exemplified above. represents an alicyclic hydrocarbon group, and R in formula (20) a1’ ~R a3’ Examples include the same as those exemplified above. The aliphatic hydrocarbon group may be, within the limits permitted by the upper limit of the number of carbon atoms, the chain hydrocarbon group and alicyclic hydrocarbon group described above. The saturated hydrocarbon group includes an aliphatic hydrocarbon group. Examples of groups in which -CH- in a saturated hydrocarbon group is replaced with -O- or -CO- include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, a cycloalkoxy group, a cycloalkylalkoxy group, and groups in which two or more of these groups are combined. Examples of these substituted groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. Examples of the structural unit (a4-1) include isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, tricyclodecanyl (meth)acrylate, and tetracyclododecenyl (meth)acrylate, as well as the structural units shown below and R in the structural unit (a4-1) in the structural units shown below. 51 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026013351000026.tif72161 When the resin (A) has such a structural unit (a4), the content thereof is preferably 1 to 40 mol %, more preferably 3 to 30 mol %, and even more preferably 5 to 20 mol %, based on all structural units of the resin (A1).

[0031] <Structural unit (a5)> The structural unit represented by formula (a5) is shown below. TIFF2026013351000027.tif3070[In formula (a5-1), R 41 represents a hydrogen atom or a methyl group. R 42 represents an aliphatic hydrocarbon group having 1 to 48 carbon atoms and containing a halogen atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-.] Examples of halogen atoms, aliphatic hydrocarbon groups, and groups in which -CH- contained in an aliphatic hydrocarbon group is replaced with -O- or -CO- include the groups described above and groups known in the art, within the range permitted by the upper limit of the number of carbon atoms. TIFF2026013351000028.tif82162

[0032] <Structural unit (a6)> The structural unit (a6) is a structural unit having an -SO2- group, and preferably has an -SO2- group in a side chain. The structural unit having an -SO2- group may have a linear structure having an -SO2- group, a branched structure having an -SO2- group, or a cyclic structure (monocyclic or polycyclic structure) having an -SO2- group. The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2026013351000029.tif4963[In formula (a6-0), R x represents a hydrogen atom or a methyl group. A xx represents an oxygen atom or a sulfur atom. A xrepresents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different.] The saturated hydrocarbon group, the group in which -CH- in the saturated hydrocarbon group is replaced with -O- or -CO-, the alkyl group, the halogen atom, the alkoxy group, the aryl group, the aralkyl group, the alkoxycarbonyl group, and the alkylcarbonyl group include the groups described above or groups known in the art, within the range permitted by the upper limit of the number of carbon atoms. The structural unit (a6-0) includes the structural units shown below and R in the structural unit (a6-1) in the structural units shown below. x The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026013351000030.tif46150

[0033] Each structural unit constituting the resin (A) can be produced by a known polymerization method (e.g., radical polymerization) using a monomer that leads to the structural unit. The content of each structural unit can be adjusted by the amount of the monomer used in producing the resin (A).

[0034] When the resin (A1) contains the structural unit (a2), the molar ratio of the structural unit (a1) to the structural unit (a2) [structural unit (a1):structural unit (a2)] is preferably 20:80 to 90:10, more preferably 30:70 to 90:10, and even more preferably 40:60 to 90:10. In the resin (A1), the molar ratio of the structural unit (a1-1) to the structural unit (a2-2) [structural unit (a1-1):structural unit (a2-2)] is, for example, 99:1 to 1:99, preferably 90:10 to 10:90, more preferably 90:10 to 60:40, and even more preferably 90:10 to 70:30. When the resin (A2) contains the structural unit (a2), the molar ratio of the structural unit (a1) to the structural unit (a2) [structural unit (a1):structural unit (a2)] is preferably 15:90 to 90:10, more preferably 20:80 to 80:20, and even more preferably 25:75 to 75:25. In the resin (A2), the molar ratio of the structural unit (a1-1) to the structural unit (a2-1) [structural unit (a1-1):structural unit (a2-2)] is, for example, 100:0 to 0:100, and preferably 100:0 to 20:80.

[0035] The weight-average molecular weight of resin (A1) and resin (A2) is preferably 3,000 or more, more preferably 4,000 or more, and preferably 600,000 or less, more preferably 500,000 or less. The weight-average molecular weight is determined by gel permeation chromatography analysis as a converted value based on standard polystyrene. Detailed analysis conditions for this analysis are described in the Examples.

[0036] The mass ratio ((A1):(A2)) of the resin (A1) and the resin (A2) contained in the resist composition is usually 20:80 to 90:10, and preferably 30:70 to 80:20. Setting the mass ratio within this range is preferable because it can further improve crack resistance. The content of resin (A1) relative to the total amount of resins contained in the resist composition is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 30% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less. The content of resin (A2) relative to the total amount of resins contained in the resist composition is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 30% by mass or more, and is preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 70% by mass or less. In the resist composition of the present invention, the content of resin (A1) and resin (A2) is preferably 80% by mass or more and 99% by mass or less, based on the total amount of solids in the resist composition. The content of resin (A1) is preferably 1% by mass or more and 98% by mass or less, and more preferably 5% by mass or more and 90% by mass or less, based on the total amount of solids in the resist composition. The content of resin (A2) is preferably 1% by mass or more and 98% by mass or less, and more preferably 5% by mass or more and 90% by mass or less, based on the total amount of solids in the resist composition. The solids and the content of each component contained in the resist composition of the present invention can be measured using known analytical methods such as liquid chromatography or gas chromatography.

[0037] <Acid generator (B)> The acid generator (B) is a compound that can be decomposed by light irradiation (exposure) to generate an acid. The generated acid can eliminate a leaving group contained in the acid labile group of the resin (A1), converting the acid labile group to a hydrophilic group (e.g., a carboxy group, a hydroxy group (phenolic hydroxyl group, etc.)). In other words, by exposing a resist composition containing the resin (A1) to light, the resist can be made soluble in a developer (an alkaline aqueous solution). The acid generator (B) may be either a nonionic or ionic type. Examples of nonionic acid generators include organic halides, sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), and sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane). Representative examples of ionic acid generators include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, and iodonium salts). Examples of anions of onium salts include sulfonate anions, sulfonylimide anions, and sulfonylmethide anions. The acid generator (B) may be a compound that generates an acid when exposed to radiation, as described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3,914,407, or European Patent No. 126,712. Compounds produced by known methods may also be used. The acid generator (B) may be used singly or in combination of two or more. The acid generator is preferably a salt represented by formula (b1) (hereinafter sometimes referred to as "acid generator (B1)"). In formula (b1), the side having a positive charge is sometimes referred to as an "organic cation," and the side having a negative charge is sometimes referred to as a "sulfonate anion." TIFF2026013351000031.tif2877[In formula (b1), R b1 represents a hydroxy group or a hydrocarbon group having 1 to 12 carbon atoms, and -CH2- contained in the hydrocarbon group may be replaced by -O- or -CO-. Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. A methylene group contained in the alicyclic ring containing the cation S may be replaced with an oxygen atom, a sulfur atom or a carbonyl group. nb1 represents an integer of 0 to 3. When nb1 is 2 or more, a plurality of R b1 may be the same or different. nb2 represents an integer of 1 to 3. A - represents a sulfonate anion]

[0038] In formula (b1), examples of the aromatic hydrocarbon group of Ar include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, a binaphthyl group, etc. The aromatic hydrocarbon group preferably has 6 to 14 carbon atoms, and more preferably has 6 to 10 carbon atoms. Examples of the substituent on the aromatic hydrocarbon group of Ar include an alkyl group having 1 to 16 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced with —O— or —CO—), a halogen atom, a cyano group, and a group formed by combining two or more of these groups. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 8, even more preferably 1 to 6, and still more preferably 1 to 4. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of groups in which -CH2- in an alkyl group is replaced with -O- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), and groups in which two or more of these groups are combined. Examples of the alkoxy group include alkoxy groups having 1 to 12 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 8, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 13 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 13 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 13 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the combined group include a group combining an alkoxy group and an alkyl group, a group combining an alkoxy group and an alkoxy group, a group combining an alkoxy group and an alkylcarbonyl group, and a group combining an alkoxy group and an alkylcarbonyloxy group. Examples of the group combining an alkoxy group and an alkyl group include alkoxyalkyl groups having 2 to 13 carbon atoms, such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, an ethoxymethyl group, etc. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. Examples of groups formed by combining an alkoxy group with another alkoxy group include alkoxyalkoxy groups having 2 to 13 carbon atoms, such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, etc. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group combining an alkoxy group and an alkylcarbonyl group include alkoxyalkylcarbonyl groups having 3 to 13 carbon atoms, such as a methoxyacetyl group, a methoxypropionyl group, an ethoxyacetyl group, an ethoxypropionyl group, etc. The number of carbon atoms in the alkoxyalkylcarbonyl group is preferably 3 to 9, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group combining an alkoxy group and an alkylcarbonyloxy group include alkoxyalkylcarbonyloxy groups having 3 to 13 carbon atoms, such as a methoxyacetyloxy group, a methoxypropionyloxy group, an ethoxyacetyloxy group, an ethoxypropionyloxy group, etc. The number of carbon atoms in the alkoxyalkylcarbonyloxy group is preferably 3 to 9, more preferably 3 to 7, and even more preferably 3 to 5.

[0039] R 1Examples of the hydrocarbon group in include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, and alicyclic hydrocarbon groups), aromatic hydrocarbon groups, and groups formed by combining these. The alkyl group may be the same as the examples of the substituents on the aromatic hydrocarbon group of Ar, within the upper limit of the carbon number allowed. The alkyl group preferably has 1 to 9 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octynyl, isooctynyl, and nonenyl groups. Examples of the alkynyl group include an ethynyl group, a propynyl group, an isopropynyl group, a butynyl group, an isobutynyl group, a tert-butynyl group, a pentynyl group, a hexynyl group, an octynyl group, and a nonynyl group. The alicyclic hydrocarbon group may be monocyclic, polycyclic, or spirocyclic, and may be saturated or unsaturated. Examples of monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. Examples of polycyclic alicyclic hydrocarbon groups include polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 10. Examples of aromatic hydrocarbon groups include aryl groups such as phenyl, naphthyl, and biphenyl. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 10. In the case of a combined group, the above groups may contain groups with different valences (such as an alkanediyl group, an alkanetriyl group, a cycloalkanediyl group, and a cycloalkanetriyl group).

[0040] Groups formed by combination include groups combining an aromatic hydrocarbon group with a chain hydrocarbon group (e.g., aromatic hydrocarbon group-alkanediyl group-*, alkyl group-aromatic hydrocarbon group-*), groups combining an alicyclic hydrocarbon group with a chain hydrocarbon group (e.g., alicyclic hydrocarbon group-alkanediyl group-*, alkyl group-alicyclic hydrocarbon group-*), and groups combining an aromatic hydrocarbon group with a alicyclic hydrocarbon group (e.g., aromatic hydrocarbon group-alicyclic hydrocarbon group-*, alicyclic hydrocarbon group-aromatic hydrocarbon group-*). * represents a bonding site. Examples of the aromatic hydrocarbon group-alkanediyl group-* include aralkyl groups such as benzyl and phenethyl. Examples of the alkyl group-aromatic hydrocarbon group-* include tolyl, xylyl, and cumenyl. Examples of the alicyclic hydrocarbon group -alkanediyl group-* include cycloalkylalkyl groups such as a cyclohexylmethyl group, a cyclohexylethyl group, and a 1-(adamantan-1-yl)methyl group. Examples of the alkyl group-alicyclic hydrocarbon group-* include cycloalkyl groups having an alkyl group such as methylcyclohexyl, dimethylcyclohexyl, and 2-alkyladamantan-2-yl. Examples of the aromatic hydrocarbon group-alicyclic hydrocarbon group-* include phenylcyclohexyl. Examples of the alicyclic hydrocarbon group-aromatic hydrocarbon group-* include cyclohexylphenyl. Note that the combinations of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may each include two or more types. Examples of groups in which -CH- in a hydrocarbon group is replaced with -O- or -CO- include alkoxy groups such as a hydroxy group, a carboxy group, a methoxy group, an ethoxy group, and a butoxy group, cycloalkoxy groups such as a cyclohexyloxy group, cycloalkylalkoxy groups such as a cyclohexylmethoxy group, alkylcarbonyl groups such as an acetyl group, alkoxycarbonyl groups such as a methoxycarbonyl group, alkylcarbonyloxy groups such as an acetyloxy group, alkoxycarbonyloxy groups such as a butoxycarbonyloxy group, and aromatic hydrocarbon group-carbonyloxy groups such as a benzoyloxy group. These substituted groups include the same groups as exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0041] Ar is preferably a phenyl group optionally having an alkyl group having 1 to 8 carbon atoms or a naphthyl group optionally having an alkyl group having 1 to 8 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), more preferably a phenyl group optionally having an alkyl group having 1 to 6 carbon atoms or a naphthyl group optionally having an alkoxy group having 1 to 6 carbon atoms, and even more preferably a phenyl group optionally having an alkyl group having 1 to 4 carbon atoms or a naphthyl group optionally having an alkoxy group having 1 to 4 carbon atoms. nb1 is preferably 0 or 1, and more preferably 0. nb2 is preferably 1 or 2, and more preferably 2.

[0042] Examples of the organic cation in formula (b1) include cations represented by the following formulae (bC-1) to (bC-23). TIFF2026013351000032.tif146151

[0043] A - The sulfonate anion represented by the formula (bA) is preferably an anion represented by the formula (bA). TIFF2026013351000033.tif2763[In formula (bA), Q 1 and Q 2each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. L b1 represents a saturated hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. Y b1 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent. -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. bA1 represents an integer of 1 to 6. When bA1 is 2 or greater, the groups in the parentheses may be the same or different.]

[0044] Q 1 and Q 2 Examples of the perfluoroalkyl group represented by the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Qb1 and Qb2 are each preferably a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms. bA1 is preferably an integer of 1 to 4, more preferably an integer of 1 to 3, even more preferably 1 or 2, and even more preferably 1.

[0045] L b1 Examples of the divalent saturated hydrocarbon group in include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may also be a group formed by combining two or more of these groups. Specific examples include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, and a heptadecane-1,17-diyl group; branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples include polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group.

[0046] L b1 Examples of the divalent saturated hydrocarbon group represented by the formula (b1-1) in which one -CH2- is replaced with -O- or -CO- include groups represented by any of formulas (b1-1) to (b1-3). In the groups represented by formulas (b1-1) to (b1-3) and specific examples thereof, groups represented by formulas (b1-4) to (b1-11), * and ** represent bonding sites, and * represents the bonding site to -Y. TIFF2026013351000034.tif26117[In formula (b1-1), L b2L represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b2 and L b3 The total number of carbon atoms is 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b4 and L b5 The total number of carbon atoms is 22 or less. In formula (b1-3), L b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and a -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b6 and L b7 The total number of carbon atoms is 23 or less.

[0047] In the groups represented by formulae (b1-1) to (b1-3), when -CH2- contained in the saturated hydrocarbon group is replaced with -O- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the saturated hydrocarbon group. As the divalent saturated hydrocarbon group, L b1 Examples of the divalent saturated hydrocarbon group include the same as the divalent saturated hydrocarbon group. L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom. L b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the divalent saturated hydrocarbon group may be substituted with -O- or -CO-. L b1 As the divalent saturated hydrocarbon group represented by the formula (b1-1), in which one -CH2- is replaced with -O- or -CO-, a group represented by formula (b1-1) or formula (b1-3) is preferred, and a group represented by formula (b1-1) is more preferred.

[0048] Examples of the group represented by formula (b1-1) include groups represented by formulas (b1-4) to (b1-8). TIFF2026013351000035.tif48120[In formula (b1-4), L b8represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. In formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b9 and L b10 The total number of carbon atoms is 20 or less. In formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b11 and L b12 The total number of carbon atoms is 21 or less. In formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b13 ~L b15 The total number of carbon atoms is 19 or less. In formula (b1-8), L b16represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b17 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. L b18 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b16 ~L b18 The total number of carbon atoms is 19 or less.

[0049] L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0050] Examples of the group represented by formula (b1-3) include groups represented by formulas (b1-9) to (b1-11). TIFF2026013351000036.tif23139[In formula (b1-9), L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b19 and L b20 The total number of carbon atoms is 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b21 , L b22 and Lb23 The total number of carbon atoms is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b24 , L b25 and L b26 The total number of carbon atoms is 21 or less. In addition, in the groups represented by formulae (b1-9) to (b1-11), when a hydrogen atom contained in the saturated hydrocarbon group is substituted with an alkylcarbonyloxy group, the number of carbon atoms before substitution is regarded as the number of carbon atoms of the saturated hydrocarbon group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, and an adamantylcarbonyloxy group. Examples of the group represented by formula (b1-4) include the following. TIFF2026013351000037.tif17153Examples of the group represented by formula (b1-5) include the following. TIFF2026013351000038.tif69163Examples of the group represented by formula (b1-6) include the following. TIFF2026013351000039.tif30166Examples of the group represented by formula (b1-7) include the following. TIFF2026013351000040.tif41170Examples of the group represented by formula (b1-8) include the following. TIFF2026013351000041.tif23146Examples of the group represented by formula (b1-2) include the following. TIFF2026013351000042.tif31161Examples of the group represented by formula (b1-9) include the following. TIFF2026013351000043.tif44137Examples of the group represented by formula (b1-10) include the following. TIFF2026013351000044.tif81166Examples of the group represented by formula (b1-11) include the following. TIFF2026013351000045.tif84164L b1 The substituents that the saturated hydrocarbon group in the formula (I) may have include a halogen atom, a hydroxy group, a glycidyloxy group, a -(CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or a group combining these. ja represents an integer of 0 to 4. ) and the like are examples of these groups. b1 Among these, a fluorine atom or a hydroxy group is preferred.

[0051] Y b1 represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent. Of the aliphatic hydrocarbon groups, an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms is preferred. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, a 2-ethylhexyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 8, and even more preferably 1 to 6. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. Examples of polycyclic alicyclic hydrocarbon groups include polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and even more preferably 3 to 10. Specific examples of the alicyclic hydrocarbon group include the groups shown below: The bonding site can be at any position. TIFF2026013351000046.tif40168 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, and a binaphthyl group. The aromatic hydrocarbon group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Y b1 Examples of the substituent that the aliphatic hydrocarbon group having 1 to 18 carbon atoms and the aromatic hydrocarbon group having 6 to 24 carbon atoms represented by the formula (I) may have include a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof. ja represents an integer of 0 to 4. -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2-, or -CO-, and a hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornyl group, and an adamantyl group. The alicyclic hydrocarbon group may have a chain hydrocarbon group, such as a methylcyclohexyl group or a dimethylcyclohexyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 12, and more preferably 3 to 10. Examples of aromatic hydrocarbon groups include aryl groups such as phenyl, naphthyl, anthryl, biphenyl, and phenanthryl. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples include aromatic hydrocarbon groups having a chain hydrocarbon group with 1 to 18 carbon atoms (such as tolyl, xylyl, cumenyl, mesityl, p-methylphenyl, p-ethylphenyl, p-tert-butylphenyl, 2,6-diethylphenyl, and 2-methyl-6-ethylphenyl), and aromatic hydrocarbon groups having an alicyclic hydrocarbon group with 3 to 18 carbon atoms (such as p-cyclohexylphenyl and p-adamantylphenyl). The aromatic hydrocarbon group preferably has 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkyl group substituted with a hydroxy group include hydroxyalkyl groups such as a hydroxymethyl group and a hydroxyethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of groups in which -CH2- in an alkyl group is replaced by -O-, -SO2-, -CO-, etc. include an alkoxy group, an alkylsulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, or a combination thereof. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, etc. The alkylsulfonyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group, etc. The alkoxycarbonyl group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, etc. The alkylcarbonyloxy group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the combined group include a group combining an alkoxy group and an alkyl group, a group combining an alkoxy group and an alkoxy group, a group combining an alkoxy group and an alkylcarbonyl group, and a group combining an alkoxy group and an alkylcarbonyloxy group. Examples of the group combining an alkoxy group and an alkyl group include alkoxyalkyl groups such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, an ethoxymethyl group, etc. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of a group formed by combining an alkoxy group with another alkoxy group include alkoxyalkoxy groups such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, etc. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group combining an alkoxy group and an alkylcarbonyl group include alkoxyalkylcarbonyl groups such as a methoxyacetyl group, a methoxypropionyl group, an ethoxyacetyl group, an ethoxypropionyl group, etc. The number of carbon atoms in the alkoxyalkylcarbonyl group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group combining an alkoxy group and an alkylcarbonyloxy group include alkoxyalkylcarbonyloxy groups such as a methoxyacetyloxy group, a methoxypropionyloxy group, an ethoxyacetyloxy group, an ethoxypropionyloxy group, etc. The number of carbon atoms in the alkoxyalkylcarbonyloxy group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5.

[0052] As the sulfonate anion represented by formula (bA), anions represented by formulas (bA-a-1) to (bA-a-14) are preferred. TIFF2026013351000047.tif131167 where L bA1 Q is a single bond or an alkanediyl group having 1 to 4 carbon atoms. 1 and Q 2 has the same meaning as above. R A1 are each independently an alkyl group having 1 to 6 carbon atoms. Specific examples of the anion represented by formula (bA) include the anions described in JP-A-2010-204646. Preferred examples of the sulfonate anion represented by formula (bA) include anions represented by formulas (bA-1) to (bA-27). TIFF2026013351000048.tif176162

[0053] The acid generator may be A of formula (b1): - Instead of the sulfonate anion shown above, the sulfonylimide anion shown below may be used. TIFF2026013351000049.tif36135A - As the anion represented by the formula: the sulfonylmethide anion shown below may be used. TIFF2026013351000050.tif30128A - As the anion represented by the formula (I), the carboxylate anion shown below may be used. TIFF2026013351000051.tif42154 The acid generator represented by formula (b1) is, for example, a combination of the above organic cation and a sulfonate anion. The acid generator represented by formula (b1) can be synthesized, for example, by the method described in JP-A-2021-56504. In the resist composition of the present invention, the content of the acid generator is preferably from 0.1 to 40 parts by mass, more preferably from 0.5 to 30 parts by mass, even more preferably from 1 to 20 parts by mass, and even more preferably from 1 to 5 parts by mass, relative to 100 parts by mass of the resin (A). The resist composition of the present invention may contain one type of acid generator (B) alone or multiple types.

[0054] <Solvent (D)> The content of the solvent (D) in the resist composition is usually 45% by mass or more, preferably 50% by mass or more, more preferably 55% by mass or more, and usually 99.9% by mass or less, preferably 99% by mass or less, more preferably 90% by mass or less. The content of the solvent (E) can be measured by known analytical means, for example, liquid chromatography or gas chromatography. Examples of the solvent (D) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; and cyclic esters such as γ-butyrolactone. One type of solvent (D) may be contained alone, or two or more types may be contained.

[0055] <Quencher (C)> The quencher in the resist composition of the present invention may be any compound that has an acid diffusion suppressing effect, i.e., an effect of trapping the acid generated from the acid generator upon exposure, and may also be a compound that can generate an acid by itself in addition to this effect. Examples of such a compound include basic nitrogen-containing organic compounds and weak acid salts. Examples of basic nitrogen-containing organic compounds include amines and ammonium salts. Examples of amines include aliphatic amines and aromatic amines. Examples of aliphatic amines include primary amines, secondary amines, and tertiary amines. Examples of the amine include compounds represented by any one of formulas (C1) to (C8) and (C1-1), and preferably the compound represented by formula (C1-1). TIFF2026013351000052.tif1937[In formula (C1), R c1 , R c2 and R c3 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a hydrogen atom contained in the alkyl group and the alicyclic hydrocarbon group may be substituted with a hydroxy group, an amino group, or an alkoxy group having 1 to 6 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms. TIFF2026013351000053.tif2352[In formula (C1-1), R c2 and R c3 has the same meaning as above. R c4 represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms. m3 represents an integer of 0 to 3, and when m3 is 2 or more, a plurality of R c4 are the same or different.] TIFF2026013351000054.tif20104 [In formula (C2), formula (C3) and formula (C4), R c5 , R c6 , R c7 and R c8 are each independently R c1 It has the same meaning as: R c9 represents an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 6 carbon atoms, or an alkanoyl group having 2 to 6 carbon atoms. n3 represents an integer from 0 to 8, and when n3 is 2 or more, multiple R c9 are the same or different.] TIFF2026013351000055.tif4097 [In formula (C5) and formula (C6), R c10 , R c11 , R c12 , R c13 and R c16 are each independently R c1 It has the same meaning as: R c14 , R c15 and R c17 are each independently R c4 It has the same meaning as: o3 and p3 each independently represent an integer of 0 to 3, and when o3 is 2 or more, a plurality of R c14 are the same or different, and when p3 is 2 or more, multiple R c15 are the same or different from each other. L c1 represents an alkanediyl group having 1 to 6 carbon atoms, -CO-, -C(=NH)-, -S-, or a divalent group formed by combining these.] TIFF2026013351000056.tif3177 [In formula (C7) and formula (C8), R c18 , R c19 and R c20 are each independently R c4 It has the same meaning as: q3, r3, and s3 each independently represent an integer of 0 to 3, and when q3 is 2 or more, a plurality of R c18 are the same or different, and when r3 is 2 or more, multiple R c19 are the same or different, and when s3 is 2 or more, multiple R c20 are the same or different from each other. L c2 represents a single bond, an alkanediyl group having 1 to 6 carbon atoms, -CO-, -C(=NH)-, -S-, or a divalent group formed by combining these.] In the formulae (C1) to (C8) and (C1-1), examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, alkoxy group, and alkanediyl group are the same as those mentioned above. Examples of the alkanoyl group include an acetyl group, a 2-methylacetyl group, a 2,2-dimethylacetyl group, a propionyl group, a butyryl group, an isobutyryl group, a pentanoyl group, and a 2,2-dimethylpropionyl group.

[0056] Examples of the compound represented by formula (C1) include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3-, or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, and methyldicyclohexylamine. amine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, and 4,4'-diamino-3,3'-diethyldiphenylmethane, among others, preferably diisopropylaniline, and particularly preferably 2,6-diisopropylaniline. Examples of the compound represented by formula (C2) include piperazine. Examples of the compound represented by formula (C3) include morpholine. Examples of the compound represented by formula (C4) include piperidine and hindered amine compounds having a piperidine skeleton as described in JP-A No. 11-52575. Examples of the compound represented by formula (C5) include 2,2'-methylenebisaniline. Examples of the compound represented by formula (C6) include imidazole and 4-methylimidazole. Examples of the compound represented by formula (C7) include pyridine and 4-methylpyridine. Examples of the compound represented by formula (C8) include 1,2-di(2-pyridyl)ethane, 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, and bipyridine.

[0057] Examples of ammonium salts include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, and choline.

[0058] Examples of the weak acid salt include salts of acids weaker than the acid generated by the acid generator (B), such as carboxylates and sulfonates, and from another perspective, also include intramolecular salts, preferably salts represented by formula (C10). TIFF2026013351000057.tif3158[In formula (C10), o and p each independently represent an integer of 0 to 4; R C21 and R C22each independently represents a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, an acyloxy group having 2 to 7 carbon atoms, an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom. If o is 2 or more, there are multiple R C21 are the same or different from each other. If p is 2 or more, there are multiple R C22 are the same or different from each other.]

[0059] Examples of the compound represented by formula (C10) include the following compounds. TIFF2026013351000058.tif21138 The content of the quencher (C) in the solid content of the resist composition is preferably from 0.0001 to 5 mass%, more preferably from 0.0001 to 4 mass%, even more preferably from 0.001 to 3 mass%, and even more preferably from 0.01 to 1.0 mass%.

[0060] <Other ingredients> The resist composition of the present invention may optionally contain components other than those described above (hereinafter, these may be referred to as "other components (F)"). There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, and dyes, can be used. When other component (F) is used, the content thereof is appropriately selected depending on the type of other component (F).

[0061] 2. Preparation of Resist Composition The resist composition of the present invention can be prepared by mixing resin (A1), resin (A2), acid generator (B), and, if necessary, resins other than resin (A1) and resin (A2), quencher (C), solvent (D), and other components (F). The order of mixing is arbitrary and is not particularly limited. The temperature during mixing can be selected from 10 to 40°C depending on the type of resin, etc., the solubility of the resin, etc. in the solvent (D), etc. The mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing method is also not particularly limited, and stirring and mixing can be used. After mixing the components, it is preferable to filter the mixture using a filter with a pore size of about 0.003 to 50 μm.

[0062] 3. Resist pattern manufacturing method The method for producing a resist pattern of the present invention comprises the steps of: (1) applying the resist composition of the present invention onto a substrate; (2) drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A step of developing the composition layer after heating is included. The resist composition can be applied to a substrate using a commonly used device such as a spin coater. Examples of the substrate include a silicon wafer. Before applying the resist composition, the substrate may be cleaned, and an anti-reflective film or the like may be formed on the substrate. The composition after application is dried to remove the solvent and form a composition layer. Drying is carried out, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a vacuum device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 30 to 600 seconds. The pressure during vacuum drying is preferably 1 to 1.0 × 10 5 It is preferable that the pressure is about Pa. After drying, the film thickness of the resulting composition is preferably 1 to 30 μm, more preferably 1.5 to 20 μm. The resulting composition layer is typically exposed using an exposure device. Examples of exposure light sources include those emitting ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), and F2 excimer laser (wavelength 157 nm); those emitting harmonic laser light in the far ultraviolet or vacuum ultraviolet range by wavelength conversion of laser light from a solid-state laser light source (YAG or semiconductor laser, etc.); and those irradiating electron beams or extreme ultraviolet light (EUV). In this specification, irradiation with these types of radiation may be collectively referred to as "exposure." During exposure, exposure is typically performed through a mask corresponding to the desired pattern. When the exposure light source is an electron beam, exposure may be performed by direct writing without using a mask. The composition layer after exposure may be subjected to a heat treatment (so-called post-exposure bake) to promote the elimination reaction of the acid labile groups in the resin (A). The heating temperature is usually about 50 to 200° C., preferably about 70 to 150° C. The heating time is usually 40 to 400 seconds, preferably 50 to 350 seconds.

[0063] The heated composition layer is usually developed using a developer in a developing device. Development methods include dipping, puddling, spraying, and dynamic dispensing. The development temperature is preferably, for example, 5 to 60°C, and the development time is preferably, for example, 5 to 600 seconds. By selecting the type of developer as follows, a positive resist pattern or a negative resist pattern can be produced.

[0064] When a positive resist pattern is produced from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. Examples include aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline). The alkaline developer may also contain a surfactant. After development, the resist pattern is preferably washed with ultrapure water, and then water remaining on the substrate and pattern is removed. When a negative resist pattern is produced from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used as the developer. Examples of organic solvents contained in organic developers include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; and aromatic hydrocarbon solvents such as anisole. The content of the organic solvent in the organic developer is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among these, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. The total content of butyl acetate and 2-heptanone in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant and a small amount of water. During development, development may be stopped by replacing the organic developer with a different type of solvent. The developed resist pattern is preferably washed with a rinse solution. There are no particular limitations on the rinse solution as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After cleaning, it is preferable to remove the rinse liquid remaining on the substrate and the pattern. By exposing a resist obtained using the resist composition of the present invention, a resist pattern with a highly accurate shape can be formed.

[0065] 4.Applications The resist composition of the present invention is useful as a resist composition for KrF excimer laser exposure, a resist composition for electron beam (EB) irradiation, or a resist composition for EUV exposure. It is particularly useful as a resist composition for KrF excimer laser exposure, and further, since it can produce an excellent resist pattern in a resist film with a thickness of 1 to 20 μm, it is useful as a resist composition for producing three-dimensional structure devices. [Example]

[0066] The present invention will be explained in more detail with reference to examples. In the examples, "%" and "parts" representing the content or amount used are by mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography under the following conditions. Column: TSKgel Multipore H XL -M x 3 + guard column (Tosoh) Eluent: tetrahydrofuran Flow rate: 1.0mL / min Detector: RI detector Column temperature: 40℃ Injection volume: 100μl Molecular weight standard: Standard polystyrene (Tosoh Corporation)

[0067] Synthesis Example 1 [Synthesis of Acid Generator (B-1)] The compound represented by the following formula was synthesized by the method described in JP 2021-56504 A. TIFF2026013351000059.tif4471

[0068] Synthesis Example 2 [Synthesis of Acid Generator (B-2)] The compound represented by the following formula was synthesized by the method described in JP 2016-130240 A. TIFF2026013351000060.tif4489

[0069] Synthesis Example 3 [Synthesis of Acid Generator (B-3)] The compound represented by the following formula was synthesized by the method described in JP 2021-56504 A. TIFF2026013351000061.tif4472

[0070] Synthesis Example 4 [Synthesis of Acid Generator (BX)] A mixed solution of 10.64 parts triethylamine, 0.95 parts ion-exchanged water, and 30.30 parts chloroform was stirred on an ice bath, and a solution of 10.10 parts of a compound represented by formula (bA-x) dissolved in 31.25 parts chloroform was added dropwise over 30 minutes, followed by stirring at 23 °C for an additional 1 hour. To the resulting mixed solution, 76.52 parts of an aqueous solution (13.1%) containing a salt represented by formula (bC-x) was added at room temperature, stirred for 15 hours, concentrated, and then 85.01 parts chloroform was added. The organic layer was separated and recovered. 21 parts ion-exchanged water was added to the recovered organic layer, stirred, and then separated. This water washing was repeated eight times. 45.51 parts tert-butyl methyl ether was added to the resulting concentrate, stirred, and filtered. To the resulting slurry, 47 parts of ion-exchanged water was added, and the mixture was stirred and filtered to obtain 6.45 parts of the salt represented by formula (BX) (yield relative to the compound represented by formula (bA-x) 27%).

[0071] Synthesis of Resins (A1) and (A2) The compounds (monomers) used in the synthesis of resins (A1) and (A2) are shown below. TIFF2026013351000063.tif39163Hereinafter, these will be referred to as "monomer (a1-1-1)" etc. depending on the formula symbol.

[0072] Synthesis Example 5 [Synthesis of Resin (A1-1)] Monomers (a1-1-16), (a1-1-9), (a2-2-1), (a3-1-1), and (a1-1-1) were charged in a molar ratio of 5:40:10:30:15. Next, propylene glycol monomethyl ether acetate was added in an amount of 2.0 times the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in proportions of 0.7 mol% and 2.1 mol%, respectively, based on the total moles of all monomers, and the mixture was heated at 75°C for approximately 5 hours. The reaction solution was then purified by pouring it into a large amount of a mixed solvent of methanol and water (4:1) three times to precipitate, resulting in a weight-average molecular weight of approximately 11.8 x 10 3 A copolymer having the following structural unit was obtained in a yield of 89%. This copolymer was designated resin (A1-1). TIFF2026013351000064.tif33163

[0073] Synthesis Example 6 [Synthesis of Resin (A1-2)] Monomers (a1-1-14), (a1-1-9), (a2-2-1), (a3-1-1), and (a4-1-8) were charged in a molar ratio of 5:40:10:30:15. Next, propylene glycol monomethyl ether acetate was added in an amount 1.5 times the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in proportions of 0.75 mol% and 2.25 mol%, respectively, based on the total moles of all monomers, and the mixture was heated at 75°C for approximately 5 hours. The reaction solution was then purified by pouring it into a large amount of a mixed solvent of methanol and water (4:1) three times to precipitate the product, resulting in a weight-average molecular weight of approximately 15.6 x 10 3A copolymer having the following structural unit was obtained in a yield of 93%. This copolymer is designated as resin (A1-2). TIFF2026013351000065.tif34160

[0074] Synthesis Example 7 [Synthesis of Resin (A1-3)] Monomer (a1-1-16), monomer (a1-1-9), monomer (a2-2-1), monomer (a3-1-1), and monomer (a1-1-1) were charged in a molar ratio of 5:40:10:30:15. Next, propylene glycol monomethyl ether acetate was added in an amount 1.5 times the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in proportions of 0.4 mol% and 1.2 mol%, respectively, based on the total moles of all monomers, and the mixture was heated at 65°C for approximately 5 hours. The reaction solution was then purified by pouring it into a large amount of a mixed solvent of methanol and water (4:1) three times to precipitate, resulting in a weight-average molecular weight of approximately 24.7 x 10 3 A copolymer having the following structural unit was obtained in a yield of 89%. This copolymer was designated resin (A1-3). TIFF2026013351000066.tif34150

[0075] Synthesis Example 8 [Synthesis of Resin (A1-4)] Monomer (a1-1-9), monomer (a2-2-1), monomer (a3-1-1), and monomer (a1-1-1) were charged in a molar ratio of 45:10:30:15. Next, propylene glycol monomethyl ether acetate was added in an amount 1.5 times the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in proportions of 0.6 mol% and 1.8 mol%, respectively, based on the total moles of all monomers, and the mixture was heated at 65°C for approximately 5 hours. The reaction solution was then purified by pouring it into a large amount of a mixed solvent of methanol and water (4:1) three times to precipitate, resulting in a weight-average molecular weight of approximately 19.9 x 10 3A copolymer having the following structural unit was obtained in a yield of 92%. This copolymer is designated as resin (A1-4). TIFF2026013351000067.tif34161

[0076] Synthesis Example 9 [Synthesis of Resin (A1-5)] Monomer (a1-1-16), monomer (a1-1-9), monomer (a2-2-1), and monomer (a3-1-1) were charged in a molar ratio of 5:55:10:30. Next, propylene glycol monomethyl ether acetate was added in an amount 1.5 times the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in proportions of 0.6 mol% and 1.8 mol%, respectively, based on the total moles of all monomers, and the mixture was heated at 65°C for approximately 5 hours. The reaction solution was then purified by pouring it into a large amount of a mixed solvent of methanol and water (4:1) three times to precipitate, resulting in a weight-average molecular weight of approximately 21.3 x 10 3 A copolymer having the following structural unit was obtained in a yield of 85%. This copolymer is designated as resin (A1-5). TIFF2026013351000068.tif31160

[0077] Synthesis Example 10 [Synthesis of Resin (A2-1)] Monomer (a1-2-2), monomer (a1-1-16), and monomer (a1-1-1) were charged in a molar ratio of 70:15:15. Next, propylene glycol monomethyl ether acetate was added in an amount 1.5 times the total mass of all monomers. Azobisisobutyronitrile was added as an initiator to the resulting mixture in an amount of 0.7 mol% based on the total moles of all monomers, and the mixture was heated at 75°C for approximately 5 hours. An aqueous solution of p-toluenesulfonic acid was then added to the polymerization reaction solution, which was stirred for 6 hours and then separated. The resulting organic layer was poured into a large amount of methanol to precipitate a resin, which was then filtered and recovered, revealing a resin with a weight-average molecular weight of approximately 36.3 x 10 3A copolymer having the following structural unit was obtained in a yield of 46%. This copolymer is designated as resin (A2-1). TIFF2026013351000069.tif33135

[0078] Synthesis Example 11 [Synthesis of Resin (A2-X)] 30 parts of polyvinylphenol ("VP-30000" manufactured by Nippon Soda Co., Ltd.) and 360 parts of methyl isobutyl ketone were charged, followed by the addition of 1.75 parts of a 0.2% p-toluenesulfonic acid solution in methyl isobutyl ketone, followed by stirring and concentration, yielding 120 parts of a methyl isobutyl ketone solution. 6.45 parts of ethyl vinyl ether was added dropwise to this solution and stirred for 3 hours. 50 parts of ion-exchanged water and 0.005 parts of triethylamine were then added to the reaction solution, followed by stirring and separation. Next, the organic layer was subjected to four separate phases of adding 50 parts of ion-exchanged water. After washing, the organic layer was concentrated, and 260 parts of propylene glycol monomethyl ether acetate was added. The mixture was concentrated again, yielding 120 parts of a propylene glycol monomethyl ether acetate solution of Resin A2-1 (solids content 27%). The weight-average molecular weight of Resin (A2-X) was 39.3 × 10 3 The protection rate of the ethoxyethyl group was 31.5%. This copolymer has the structural unit of the following formula and is designated as resin (A2-X). TIFF2026013351000070.tif31104

[0079] <Preparation of Resist Composition> The components shown in Table 1 were mixed and dissolved to obtain a mixture, which was then filtered through a fluororesin filter with a pore size of 5 μm to prepare a resist composition. [Table 1] TIFF2026013351000072.tif67157

[0080] <Resin> (A1-1): Resin (A1-1) (A1-2): Resin (A1-2) (A1-3): Resin (A1-3) (A1-4): Resin (A1-4) (A1-5): Resin (A1-5) (A2-1):Resin (A2-1) (A2-X):Resin (A2-X) <Acid generator (B)> (B-1): Acid generator (B-1) (B-2): Acid generator (B-2) (B-3): Acid generator (B-3) (BX): Acid generator (BX) <Quencher (C)> (C-1): N,N-dicyclohexylmethylamine (manufactured by Aldrich) <Solvent (D)> (D-1): Propylene glycol monomethyl ether acetate (D-2): γ-butyrolactone (D-3): n-Butyl acetate (D-4): Propylene glycol monomethyl ether

[0081] Examples 1 to 8, Comparative Examples 1 to 4 (KrF exposure evaluation of resist composition) A 4-inch silicon wafer was treated with hexamethyldisilazane on a direct hot plate at 90°C for 60 seconds. A resist composition was spin-coated onto this silicon wafer so that the composition layer had a thickness of 16 μm. The wafer was then pre-baked on a direct hot plate at 150°C for 90 seconds to form a composition layer. The composition layer formed on the wafer was exposed to a KrF excimer laser exposure machine [NSR-2250EX12B; manufactured by Nikon Corporation, NA=0.55, Conventional, σ=0.80] through a mask to form a trench pattern (trench width 3 μm) while gradually changing the exposure dose. After exposure, post-exposure baking was carried out on a hot plate at 120° C. for 90 seconds, and then puddle development was carried out in a 2.38 mass % aqueous solution of tetramethylammonium hydroxide for 90 seconds to obtain a resist pattern. The resist pattern obtained after development was observed under a scanning electron microscope, and the exposure dose at which a trench pattern with a width of 3 μm was obtained was taken as the effective sensitivity.

[0082] <Resolution evaluation> The resist patterns obtained at the effective sensitivity were observed under a scanning electron microscope. Those in which a 3 μm trench pattern could not be formed were marked with an "X", those in which a 3 μm trench pattern could be formed but residue was generated were marked with a "△", and those in which no residue was generated were marked with a "◯". <Shape evaluation> The 3 μm trench patterns obtained at the effective sensitivity were observed under a scanning electron microscope, and those with a good top and bottom shape close to a rectangle [Fig. 1(a)] were evaluated as "◎", those with a round top [Fig. 1(b)] as "〇", and those with a round top and a notch at the bottom [Fig. 1(c)] as "×". The results are shown in Table 2. <Crack evaluation> The patterned silicon wafer obtained after development was visually inspected for the presence or absence of cracks. Those without cracks were marked "◯", and those in which cracks were observed were marked "X". [Table 2] [Industrial Applicability]

[0083] The resist composition of the present invention is capable of producing a resist pattern that has excellent resolution, a good shape, and is resistant to cracking, and is therefore suitable for semiconductor microfabrication and extremely useful industrially.

Claims

1. A resist composition comprising: a resin (A) that includes a structural unit having an acid labile group; and an acid generator (B) represented by formula (b1): Resin (A) is a resist composition containing resin (A1) and resin (A2). Resin (A1): A resin containing a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-2), but not containing a structural unit represented by formula (a1-2) or a structural unit represented by formula (a2-1). Resin (A2): A resin containing a structural unit represented by formula (a1-1) and a structural unit represented by formula (a2-1), but not containing a structural unit represented by formula (a1-2). [In formula (b1), R ｂ１ represents a hydroxy group or a hydrocarbon group having 1 to 12 carbon atoms, and —CH ２ - may be replaced by -O- or -CO-. Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. -CH contained in the ring that constitutes the cation ２ - may be replaced by -O-, -S- or -CO-. nb1 represents an integer of 0 to 3. When nb1 is 2 or more, a plurality of R ｂ１ may be the same or different. nb2 represents an integer of 1 to 3. A － represents a sulfonate anion. [In formula (a2-2), R ａ２１ represents a hydrogen atom or a methyl group. L ａ２１ is -O- or *-O-(CH ２ ) ｋ０１ represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R ａ２２ represents a hydroxy group or a carboxy group. R ａ２３ , and R ａ２４ each independently represents a hydrogen atom, a methyl group, a hydroxy group, or a carboxy group. [In formula (a1-1) and formula (a1-2), R ａ１ , R ａ２ and R ａ３ each independently represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R ａ１ and R ａ２ are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R ａ３ represents an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms. R ａ１’ and R ａ２’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms; R ａ３’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R ａ１’ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R ａ２’ and R ａ３’ are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atom and oxygen atom to which they are bonded. ２ - may be replaced by -O- or -S-. L ａ０１ is -O- or *-O-(CH ２ ) ｋ０１ represents —CO—O—, k01 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R ａ４ and R ａ５ each independently represents a hydrogen atom or a methyl group. R ａ６ represents an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. m represents an integer of 0 to 4; When m is 2 or more, a plurality of R ａ６ may be the same or different.] [In formula (a2-1), R ａ７ represents a hydrogen atom or a methyl group. R ａ１０ represents a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. m' represents an integer of 0 to 4. When m' is 2 or more, a plurality of R ａ１０ may be the same or different from each other. m'' represents an integer of 1 to 4. However, the sum of m' and m'' is 5 or less.]

2. A in formula (b1) － The resist composition according to claim 1, wherein the compound is represented by formula (bA): [In formula (bA), Q １ and Q ２ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. L ｂ１ represents a saturated hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and —CH ２ - may be replaced by -O- or -CO-. Y ｂ１ represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent. ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. bA1 represents an integer of 1 to 6. When bA1 is 2 or more, the groups in the parentheses may be the same or different.]

3. 2. The resist composition according to claim 1, wherein the content of the resin (A1) is from 40% by mass to 80% by mass based on the total amount of resins.

4. A method for producing a resist pattern, comprising: (1) A step of applying the resist composition according to any one of claims 1 to 3 onto a substrate; (2) drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) Step of developing the composition layer after heating A manufacturing method comprising:

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