Resist compositions, methods for forming resist patterns, compounds, and polymer compounds

Abstract

The present invention provides a resist composition that enables high sensitivity in resist pattern formation and enhances lithography characteristics such as pattern roughness, exposure margin, and resolution. [Solution] A resist composition is employed that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid. It is characterized by containing a resin component having a constituent unit (a0) derived from a compound represented by the general formula (a0-m0). In the general formula (a0-m0), W 0 X represents a polymerizable group-containing group. 0 L represents a hydrogen atom or an alkyl group. 0 R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. 0 represents an acid-dissociating group. However, R 0 In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α and β positions of the carbon atom (C*) form a carbon-carbon bond other than a single bond. [C1] TIFF2026168520000111.tif31170

Description

[Technical Field]

[0001] The present invention relates to resist compositions, resist pattern formation methods, compounds, and polymer compounds. [Background technology]

[0002] In recent years, advances in lithography technology have led to rapid miniaturization of patterns in the manufacturing of semiconductor devices and liquid crystal display elements. Generally, miniaturization is achieved by shortening the wavelength (increasing the energy) of the exposure light source. Resist materials are required to possess lithography characteristics such as sensitivity to these exposure light sources and resolution that can reproduce patterns of fine dimensions. Conventionally, chemically amplified resist compositions have been used as resist materials that satisfy these requirements. These compositions contain a base component whose solubility in a developer changes due to the action of an acid, and an acid generator component that generates acid upon exposure.

[0003] In chemically amplified resist compositions, a resin component having multiple structural units is generally used as the substrate component to improve lithography characteristics and other properties. For example, Patent Document 1 proposes a resist composition containing a polymer compound having a structural unit that includes a hydrophobic arylene group in its side chain. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2025-004966 [Overview of the project] [Problems that the invention aims to solve]

[0005] As lithography technology continues to advance and resist patterns become increasingly miniaturized, for example, EUV and EB lithography aim to form fine patterns of tens of nanometers. As resist pattern dimensions become smaller, it becomes necessary to improve lithographic characteristics such as sensitivity, pattern roughness, exposure margin, and resolution without any trade-offs.

[0006] The present invention has been made in view of the above circumstances, and aims to provide a resist composition that can be made highly sensitive in the formation of a resist pattern and can improve lithography characteristics such as pattern roughness, exposure margin and resolution, a method for forming a resist pattern using the resist composition, a polymer compound useful as a substrate component, and a compound that can be used for its synthesis. [Means for solving the problem]

[0007] To solve the above problems, the present invention employs the following configuration. In other words, a first aspect of the present invention is a resist composition that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, the resist composition containing a resin component (A1) whose solubility in a developer changes due to the action of the acid, wherein the resin component (A1) has a constituent unit (a0) derived from a compound represented by the following general formula (a0-m0).

[0008] [ka] [In the formula, W 0 X represents a polymerizable group-containing group. 0 L represents a hydrogen atom or an alkyl group. 0 R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. 0 represents an acid-dissociating group. However, R 0 In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond.

[0009] A second aspect of the present invention is a resist pattern forming method, comprising the steps of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film, and developing the exposed resist film to form a resist pattern.

[0010] A third aspect of the present invention is a compound represented by the following general formula (a0-m0).

[0011]

Chemical Formula

[0012] A fourth aspect of the present invention is a polymer compound having a structural unit derived from the compound according to the third aspect.

Effects of the Invention

[0013] An object of the present invention is to provide a resist composition that achieves high sensitivity in resist pattern formation and can improve lithography properties such as pattern roughness, exposure margin and resolution, a resist pattern forming method using the resist composition, a polymer compound useful as a base component, and a compound usable for the synthesis thereof.

Modes for Carrying Out the Invention

[0014] In this specification and in the claims, "aliphatic" is defined as a concept relative to aromatic, meaning a group, compound, etc., that does not possess aromaticity. Unless otherwise specified, "alkyl group" includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to alkyl groups within alkoxy groups. Unless otherwise specified, the term "alkylene group" includes linear, branched, and cyclic divalent saturated hydrocarbon groups. Examples of "halogen atoms" include fluorine, chlorine, bromine, and iodine atoms. "Constituent unit" refers to the monomer unit (monomer unit) that makes up a polymer compound (resin, polymer, copolymer). When it is stated that a group "may have substituents," this includes both cases where a hydrogen atom (-H) is substituted with a monovalent group and cases where a methylene group (-CH2-) is substituted with a divalent group. "Exposure" is a concept that includes all forms of radiation exposure.

[0015] The term "acid-dissociable group" refers to both (i) a group that has acid-dissociability, in which the bond between the acid-dissociable group and an adjacent atom can be cleaved by the action of an acid, and (ii) a group in which, after some of the bonds are cleaved by the action of an acid, a decarboxylation reaction occurs, further causing the bond between the acid-dissociable group and an adjacent atom to be cleaved. The acid-dissociable group constituting the acid-degradable group must be less polar than the polar group generated by its dissociation. This means that when the acid-dissociable group dissociates due to the action of acid, a polar group with higher polarity is generated, increasing the polarity. As a result, the overall polarity of component (A1) increases. This increase in polarity relatively changes the solubility in the developer; solubility increases when the developer is an alkaline developer, and decreases when the developer is an organic developer.

[0016] "Base material components" are organic compounds that have film-forming ability. Organic compounds used as base material components are broadly classified into nonpolymers and polymers. Nonpolymers typically have a molecular weight of 500 or more and less than 4000 (hereinafter referred to as "low molecular weight compounds"). Hereinafter, when "resins," "high molecular weight compounds," or "polymers" are used, polymers with a molecular weight of 1000 or more are referred to. For polymers, the weight-average molecular weight in terms of polystyrene obtained by GPC (gel permeation chromatography) shall be used as the molecular weight.

[0017] "Induced structural units" refer to structural units formed by the cleavage of multiple bonds between carbon atoms, such as ethylenic double bonds. "Acrylic acid ester" may have a substituent that replaces the hydrogen atom bonded to the α-carbon atom. αx ) is an atom or group other than a hydrogen atom. Also, substituents (R αx Itaconic acid diesters in which ) are substituted with substituents containing an ester bond, or substituents (R αx This also includes α-hydroxyacrylic esters in which the α group is substituted with a hydroxyalkyl group or a group that modifies the hydroxyl group thereof. Unless otherwise specified, the α-carbon atom of the acrylic acid ester refers to the carbon atom to which the carbonyl group of acrylic acid is bonded. Hereafter, acrylic acid esters in which the hydrogen atom bonded to the α-carbon atom is replaced by a substituent are sometimes called α-substituted acrylic acid esters.

[0018] The term "derivative" refers to a compound in which the α-position hydrogen atom of the target compound is substituted with another substituent such as an alkyl group or alkyl halide, as well as derivatives thereof. Examples of such derivatives include those in which the hydrogen atom of the hydroxyl group of the target compound (which may have the α-position hydrogen atom substituted with a substituent) is substituted with an organic group; and those in which a substituent other than a hydroxyl group is bonded to the target compound (which may have the α-position hydrogen atom substituted with a substituent). Unless otherwise specified, the α-position refers to the first carbon atom adjacent to the functional group. As substituents that substitute the hydrogen atom at the α-position of hydroxystyrene, R αx Similar examples include the above.

[0019] In this specification and in the claims, depending on the structure represented by the chemical formula, an asymmetric carbon may be present, and enantioisomers or diastereomers may exist. In such cases, a single chemical formula will represent all of these isomers. These isomers may be used individually or as a mixture.

[0020] (Resist composition) One embodiment of the resist composition according to the first aspect generates acid upon exposure, and its solubility in a developer changes due to the action of the acid. Such a resist composition contains a base component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer changes due to the action of the acid.

[0021] In the resist composition of this embodiment, component (A) may generate acid upon exposure, or an additive component formulated separately from component (A) may generate acid upon exposure. The resist composition of this embodiment may specifically (1) further contain an acid generating agent component (B) (hereinafter referred to as "component (B)") that generates acid upon exposure; (2) component (A) may be a component that generates acid upon exposure; or (3) component (A) may be a component that generates acid upon exposure and also contains component (B). In other words, in the cases of (2) and (3) above, component (A) is a "substrate component that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid." When component (A) is a substrate component that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid, it is preferable that component (A1), described later, is a resin that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid. As such a resin, a polymer compound having a constituent unit that generates acid upon exposure can be used. As the constituent unit that generates acid upon exposure, the constituent unit (a5) and constituent unit (a6), described later, can be used.

[0022] When a resist film is formed using the resist composition of this embodiment and selective exposure is performed on the resist film, for example, acid is generated from component (B) in the exposed areas of the resist film, and the solubility of component (A) in the developer changes due to the action of this acid, while the solubility of component (A) in the developer does not change in the unexposed areas of the resist film. As a result, a difference in solubility in the developer occurs between the exposed and unexposed areas of the resist film. Therefore, when the resist film is developed, if the resist composition is positive type, the exposed areas of the resist film are dissolved and removed to form a positive type resist pattern, and if the resist composition is negative type, the unexposed areas of the resist film are dissolved and removed to form a negative type resist pattern.

[0023] The resist composition of this embodiment may be a positive-type resist composition or a negative-type resist composition. Furthermore, the resist composition of this embodiment may be for an alkaline development process that uses an alkaline developer for the development process during resist pattern formation, or for a solvent development process that uses a developer containing an organic solvent (organic developer) for the development process.

[0024] <Base material component (A)> In the resist composition of this embodiment, component (A) includes a resin component (A1) (hereinafter also referred to as "component (A1)") whose solubility in the developer solution changes due to the action of an acid. By using component (A1), the polarity of the substrate component changes before and after exposure, so that good development contrast can be obtained not only in the alkaline development process but also in the solvent development process. (A) Component (A1) may be used in combination with other high-molecular-weight compounds and / or low-molecular-weight compounds. In the resist composition of this embodiment, component (A) may be used alone or in combination of two or more types.

[0025] (A1) About the ingredients Component (A1) is a resin component whose solubility in the developer changes due to the action of an acid. Component (A1) has a constituent unit (a0) derived from a compound represented by the general formula (a0-m0) described below. Component (A1) may have other constituent units in addition to the constituent unit (a0) as needed.

[0026] ≪Constituent Unit (a0)≫ The constituent unit (a0) is a constituent unit (a0) derived from the compound represented by the following general formula (a0-m0).

[0027] [ka] [In the formula, W 0 X represents a polymerizable group-containing group. 0 L represents a hydrogen atom or an alkyl group. 0 R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. 0 represents an acid-dissociating group. However, R 0 In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond.

[0028] In the aforementioned formula (a0-m0), W 0 Regarding the polymerizable group-containing group in the above, the "polymerizable group" refers to a group that enables a compound having a polymerizable group to polymerize via radical polymerization or the like, and for example, means a group containing a multiple bond between carbon atoms such as an ethylenic double bond. Examples of the polymerizable group include a vinyl group, α-methylvinyl group, allyl group, acryloyl group, methacryloyl group, fluorovinyl group, difluorovinyl group, trifluorovinyl group, difluorotrifluoromethylvinyl group, trifluoroallyl group, perfluoroallyl group, trifluoromethylacryloyl group, nonafluorobutylacryloyl group, vinyl ether group, fluorine-containing vinyl ether group, allyl ether group, fluorine-containing allyl ether group, styryl group, vinylnaphthyl group, fluorine-containing styryl group, fluorine-containing vinylnaphthyl group, norbornyl group, fluorine-containing norbornyl group, silyl group, maleimide group and the like.

[0029] The polymerizable group-containing group may be a group composed only of a polymerizable group, or a group composed of a polymerizable group and another group other than the polymerizable group. Examples of the other group other than the polymerizable group include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like. As the polymerizable group-containing group, for example, Formula: C(R X11 )(R X12 )=C(R X13 )-Ya x0 - is a group represented by are preferably mentioned. In the aforementioned formula, R X11 , R X12 and R X13 each independently represent an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom or a hydrogen atom, and Ya x0 represents a divalent linking group or a single bond. Examples of the divalent linking group for Ya x0 include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like. Ya x0Examples of the divalent linking group in the above include an ester bond (-C(=O)-O-), an oxycarbonyl group (-O-C(=O)-), an ether bond (-O-), a linear or branched alkylene group, an arylene group, and combinations thereof.

[0030] In the aforementioned formula (a0-m0), X 0 The alkyl group in the above is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. Among them, X 0 is preferably a hydrogen atom, a methyl group, or an ethyl group, more preferably a hydrogen atom or a methyl group, and a hydrogen atom is even more preferable particularly from the viewpoints of pattern roughness and exposure margin.

[0031] In the aforementioned formula (a0-m0), L 0 The aliphatic hydrocarbon group in the above means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated (for example, an alkenylene group, an alkynylene group, etc.). Such L 0 The aliphatic hydrocarbon group in the above is a chain aliphatic hydrocarbon group or a cyclic aliphatic hydrocarbon group.

[0032] · Chain aliphatic hydrocarbon group The chain aliphatic hydrocarbon group may be a linear aliphatic hydrocarbon group or a branched aliphatic hydrocarbon group. The linear aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, even more preferably 1 to 3 carbon atoms, particularly preferably 1 to 2 carbon atoms, and most preferably 1 carbon atom. Specific examples of the linear aliphatic hydrocarbon group include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and the like. The branched aliphatic hydrocarbon group preferably has 2 to 6 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. Examples of branched aliphatic hydrocarbon groups include alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -CH(CH(CH3)2)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. In the alkylalkylene group, alkyl groups having 1 to 3 carbon atoms are preferred, and methyl groups are more preferred.

[0033] The aforementioned linear or branched aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include halogen atoms and hydroxyl groups.

[0034] • Cyclic aliphatic hydrocarbon group A cyclic aliphatic hydrocarbon group is a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring, and preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. A preferred monocyclic alicyclic hydrocarbon group is a monocycloalkane from which two hydrogen atoms have been removed. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopropane, cyclopentane, cyclohexane, etc. A preferred polycyclic alicyclic hydrocarbon group is a polycycloalkane from which two hydrogen atoms have been removed, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.

[0035] The aforementioned cyclic aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and carbonyl groups.

[0036] L 0 In particular, it is preferable that the aliphatic hydrocarbon group has 1 to 3 carbon atoms, more preferably that it has 1 to 2 carbon atoms, and most preferably that it has 1 carbon atom. Or, L 0 Among these, chain-like aliphatic hydrocarbon groups and monocyclic alicyclic hydrocarbon groups are preferred, chain-like aliphatic hydrocarbon groups are more preferred, and linear aliphatic hydrocarbon groups are even more preferred.

[0037] In the above equation (a0-m0), R 0 represents an acid-dissociating group. However, R 0 In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond. In this context, "carbon-carbon bonds other than single bonds formed between the α-position of the carbon atom (C*) and the β-position of the carbon atom (C*)" means carbon-carbon bonds having a pi bond, and includes double bonds between carbon atoms, triple bonds between carbon atoms, and bonds in which the pi bond in aromatic rings such as benzene rings is resonance-stabilized. Double bonds and triple bonds between carbon atoms are collectively referred to as "carbon-carbon unsaturated bonds" below.

[0038] R 0 Suitable acid-dissociating groups in the following general formula (R 0 -1) an acid-dissociating group represented by the following general formula (R 0 Examples of acid-dissociating groups include those represented by (-2).

[0039] ·General formula (R 0Acid dissociation group represented by -1) R in the above equation (a0-m0) 0 This is the following general formula (R 0 It is preferable that the acid-dissociable group is represented by (-1).

[0040] [ka] [In the formula, C* T This indicates that it is a tertiary carbon atom. X1 is the aforementioned tertiary carbon atom (C* T ) and the α position of the tertiary carbon atom (C* T It is an aromatic group having a carbon-carbon bond other than a single bond formed with the β position of the tertiary carbon atom (C* T ) and the α position of the tertiary carbon atom (C* T It is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed at the β position of (the aliphatic hydrocarbon group may have substituents). Y1 and R Z1 Each of these is independently a substituted linear saturated hydrocarbon group, or they are bonded to each other to form a substituted saturated aliphatic cyclic group. *1 indicates a bond to an adjacent oxygen atom (-O-).

[0041] The above formula (R 0 -1) Medium, R X1 In the tertiary carbon atom (C* T Aromatic groups having carbon-carbon bonds other than the single bond formed between the α and β positions of a molecule are functional groups having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic, polycyclic, or have substituents that substitute for the hydrogen atoms of the aromatic ring. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. The number of carbon atoms in the aromatic hydrocarbon ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 5 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents that substitute for hydrogen atoms in the aromatic hydrocarbon ring. Specific examples of aromatic hydrocarbon rings include benzene, naphthalene, anthracene, and phenanthrene. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0042] R X1 The number of carbon atoms in the aromatic group is preferably 4 to 30, more preferably 4 to 20, even more preferably 4 to 15, and particularly preferably 4 to 12. R X1 Specific examples of aromatic groups in this context include groups obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle (aryl group or heteroaryl group); and groups obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.).

[0043] R X1 The aromatic group in may have substituents. Examples of substituents include hydroxyl groups, carboxyl groups, halogen atoms (fluorine, chlorine, bromine, iodine), alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.), and alkyloxycarbonyl groups;-R P1 , -R P2 -OR P1 , -R P2 -CO-R P1 , -R P2 -CO-OR P1 , -R P2 -O-CO-R P1 , -R P2 -OH, -R P2 -CN or -R P2 -COOH (These substituents are collectively referred to as "Ra") x5Also referred to as."), and the like. Here, R P1 is a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic group having 4 to 30 carbon atoms. Further, R P2 is a single bond, a divalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic group having 4 to 30 carbon atoms. Provided that R P1 and R P2 some or all of the hydrogen atoms contained in the linear saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group and aromatic group may be substituted with fluorine atoms. The aliphatic cyclic saturated hydrocarbon group may have one or more of the aforementioned substituents singly, or may have one or more of each of a plurality of types of the aforementioned substituents.

[0044] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group and the like. Examples of the monovalent linear saturated hydrocarbon group having 1 to 10 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 the like. Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, and a cyclododecyl group; and polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7]decanyl group, a tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and an adamantyl group. Examples of the monovalent aromatic group having 4 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

[0045] Among them, R X1 In this context, the aromatic group having carbon-carbon bonds other than single bonds is preferably a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle (aryl group or heteroaryl group), more preferably having 4 to 15 carbon atoms, and even more preferably having 4 to 10 carbon atoms. R X1 In this context, the aromatic groups having carbon-carbon bonds other than single bonds are preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, phenanthrene, or thiophene, more preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or thiophene, even more preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, or thiophene, particularly preferably groups obtained by removing one or more hydrogen atoms from benzene or thiophene, and most preferably groups obtained by removing one or more hydrogen atoms from benzene.

[0046] R X1 In this, aromatic groups having carbon-carbon bonds other than single bonds may have substituents. X1 Preferred substituents that the aromatic group in the compound may have include, for example, methyl, ethyl, propyl, hydroxyl, halogen, and alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.). Among these, halogen atoms are more preferred, and iodine atoms are particularly preferred, from the viewpoint of increasing sensitivity and reducing pattern roughness.

[0047] The above formula (R 0 -1) Medium, R X1 In the tertiary carbon atom (C* T Aliphatic hydrocarbon groups having a carbon-carbon unsaturated bond formed between the α and β positions of ) include linear or cyclic alkenyl groups and linear alkynyl groups.

[0048] Chain-like or cyclic alkenyl groups: R X1As for the chain alkenyl group in the above, it may be linear or branched, preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, still more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms. Examples of the linear alkenyl group include a vinyl group, 1-propenyl group, 1-butenyl group and the like. Examples of the branched alkenyl group include a 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group and the like. R X1 As for the cyclic alkenyl group in the above, examples thereof include a cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group and the like.

[0049] Chain alkynyl group: R X1 As for the chain alkynyl group in the above, it may be linear or branched, and examples thereof include linear alkynyl groups such as an ethynyl group, 1-propynyl group, 1-butynyl group, and 1-pentynyl group; branched alkynyl groups such as a 3,3-dimethyl-1-butynyl group, and the like.

[0050] Among them, R X1 The aliphatic hydrocarbon group having a carbon-carbon unsaturated bond in the above is preferably a chain alkenyl group or a chain alkynyl group, and more preferably a chain alkenyl group.

[0051] R X1 The aliphatic hydrocarbon group having a carbon-carbon unsaturated bond in the above may have a substituent. R X1 Preferable substituents that the aliphatic hydrocarbon group in the above may have include, for example, an alkoxy group, halogen atom, halogenated alkyl group, hydroxy group, carbonyl group, oxo group (=O), nitro group, amino group and the like.

[0052] In the aforementioned formula (R 0 -1), R Y1 and R Z1are each independently a chain saturated hydrocarbon group which may have a substituent, or are bonded to each other to form a saturated aliphatic cyclic group which may have a substituent. In the formula (R 0 -1), examples of the chain saturated hydrocarbon group for R Y1 and R Z1 each independently include a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms. Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms for R Y1 and R Z1 include linear alkyl groups such as methyl group, ethyl group, n-propyl group, n-butyl group and n-pentyl group; and branched alkyl groups such as isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group and 2,2-dimethylbutyl group. Among these, an alkyl group having 1 to 5 carbon atoms is preferred, an alkyl group having 1 to 3 carbon atoms is more preferred, a methyl group and an ethyl group are still more preferred, and a methyl group is particularly preferred. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group may be substituted with a substituent. Examples of the substituent include the same groups as the aforementioned Ra x5 .

[0053] In the formula (R 0 -1), the saturated aliphatic cyclic group formed by R Y1 and R Z1 bonded to each other may be a polycyclic group or a monocyclic group. As the monocyclic saturated aliphatic cyclic group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic saturated aliphatic cyclic group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane.

[0054] The saturated aliphatic cyclic group referred to here may also be a saturated aliphatic heterocycle in which some of the carbon atoms constituting it are replaced by heteroatoms. Examples of heteroatoms in a saturated aliphatic heterocycle include oxygen, sulfur, and nitrogen atoms. Specific examples of saturated aliphatic heterocycles include tetrahydrofuran rings and tetrahydropyran rings. Some or all of the hydrogen atoms in this saturated aliphatic cyclic group may be substituted with substituents. Examples of such substituents include hydroxyl groups, carboxyl groups, halogen atoms (fluorine, chlorine, bromine, iodine), oxo groups (=O), alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.), and alkyloxycarbonyl groups;-R P1 , -R P2 -OR P1 , -R P2 -CO-R P1 , -R P2 -CO-OR P1 , -R P2 -O-CO-R P1 , -R P2 -OH, -R P2 -CN or -R P2 -COOH(R P1 , R P2 Examples include (as described above). Preferred substituents that this saturated aliphatic cyclic group may have include, for example, a halogen atom, an oxo group (=O), and -R P1 These are some examples.

[0055] The general formula (R) described above 0 As an acid-dissociating group represented by -1), the following general formula (R 0 Acid-dissociating group represented by -1-1), the following general formula (R 0 Acid-dissociating groups represented by -1-2), the following general formula (R 0 Acid-dissociable groups represented by -1-3) are preferred.

[0056] [ka] [Formula(R 0-1-1) In this group, Yaa is a tertiary carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra 104 is an aromatic group which may have substituents. Formula (R 0 -1-2) In these groups, Ya is a tertiary carbon atom. Xa is a group that forms a cyclic hydrocarbon group with Ya. Some or all of the hydrogen atoms in this cyclic hydrocarbon group may be substituted. Ra 101 ~Ra 103 Each of these is independently a hydrogen atom, a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms in these linear saturated hydrocarbon groups and aliphatic cyclic saturated hydrocarbon groups may be substituted. 101 ~Ra 103 Two or more of these may be bonded together to form a ring structure. Formula (R 0 -1-3) Middle, Ra' 12 and Ra' 13 Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. 14 is the formula (R 0 -1-3) is an aromatic group having a carbon-carbon bond other than the single bond formed between the α and β positions of the tertiary carbon atom, or formula (R 0 -1-3) is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed between the α and β positions of a tertiary carbon atom (the aliphatic hydrocarbon group may have substituents). * indicates a bond.

[0057] Formula (R 0 -1-1) In this case, the aliphatic cyclic group formed by Xaa together with Yaa is the R mentioned above. Y1 and R Z1 The groups listed above are preferred as saturated aliphatic cyclic groups formed by the bonding of these groups with one another. The aliphatic cyclic group formed by Xaa together with Yaa is preferably a monocyclic saturated aliphatic cyclic group, more preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane having 3 to 6 carbon atoms, and even more preferably a group obtained by removing one or more hydrogen atoms from cyclopentane or cyclohexane. The saturated aliphatic cyclic group referred to here may also be a saturated aliphatic heterocycle in which some of the carbon atoms constituting it are replaced by heteroatoms. Examples of saturated aliphatic heterocycles include tetrahydrofuran rings and tetrahydropyran rings. Some or all of the hydrogen atoms in the aliphatic cyclic group formed by Xaa together with Yaa may be substituted with substituents. The substituents include the aforementioned R. Y1 and R Z1 These substituents are similar to those that may be present on a saturated aliphatic cyclic group formed by the bonding of these atoms to one another. Some or all of the hydrogen atoms on this saturated aliphatic cyclic group may be substituted with substituents. Preferred substituents that this saturated aliphatic cyclic group may have include, for example, halogen atoms, oxo groups (=O), and -R P1 (R P1 Examples include the same as described above.

[0058] Formula (R 0 -1-1) During, Ra 104 Aromatic groups in this context include aromatic groups with 4 to 30 carbon atoms, such as groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring or an aromatic heterocycle. Among these, Ra 104 The group is preferably one obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, phenanthrene, or thiophene; more preferably one obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or thiophene; even more preferably one obtained by removing one or more hydrogen atoms from benzene, naphthalene, or thiophene; particularly preferably one obtained by removing one or more hydrogen atoms from benzene or thiophene; and most preferably one obtained by removing one or more hydrogen atoms from benzene.

[0059] Formula (R 0 -1-1) During, Ra 104Examples of substituents that may be present include methyl groups, ethyl groups, propyl groups, hydroxyl groups, halogen atoms, and alkoxy groups (methoxy groups, ethoxy groups, propoxy groups, butoxy groups, etc.). Among these, halogen atoms are more preferred from the viewpoint of increasing sensitivity and reducing pattern roughness, and iodine atoms are particularly preferred.

[0060] Formula (R 0 -1-2) In these, the cyclic hydrocarbon group formed by Xa together with Ya is the R Y1 and R Z1 The groups listed above are preferred as saturated aliphatic cyclic groups formed by the bonding of these groups with one another. The cyclic hydrocarbon group formed by Xa and Ya is preferably a monocyclic saturated aliphatic cyclic group, more preferably a monocycloalkane with 3 to 6 carbon atoms from which one or more hydrogen atoms have been removed, and even more preferably a cyclopentane or cyclohexane from which one or more hydrogen atoms have been removed. The saturated aliphatic cyclic group here may also be a saturated aliphatic heterocycle in which some of the carbon atoms constituting it are substituted with heteroatoms. Some or all of the hydrogen atoms in the cyclic hydrocarbon group formed by Xa and Ya may be substituted with substituents. The substituents include the aforementioned R. Y1 and R Z1 These substituents are similar to those that may be present on a saturated aliphatic cyclic group formed by the bonding of these atoms to one another. Some or all of the hydrogen atoms on this saturated aliphatic cyclic group may be substituted with substituents. Preferred substituents that this saturated aliphatic cyclic group may have include, for example, halogen atoms, oxo groups (=O), and -R P1 (R P1 Examples include the same as described above.

[0061] Formula (R 0 -1-2) During, Ra 101 ~Ra 103 Examples of monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups. Ra 101 ~Ra103 Examples of monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl groups; bicyclo[2.2.2]octanyl, tricyclo[5.2.1.0 2,6 ]decanyl group, tricyclo[3.3.1.1 3,7 ]decanyl group, tetracyclo[6.2.1.1 3,6 .0 2,7 Examples include polycyclic aliphatic saturated hydrocarbon groups such as dodecanyl groups and adamantyl groups. Ra 101 ~Ra 103 Of these, from the viewpoint of ease of synthesis, hydrogen atoms and monovalent chain saturated hydrocarbon groups having 1 to 10 carbon atoms are preferred, and among these, hydrogen atoms, methyl groups, and ethyl groups are more preferred, hydrogen atoms and methyl groups are even more preferred, and hydrogen atoms are particularly preferred.

[0062] The above Ra 101 ~Ra 103 Examples of substituents on a chain-like saturated hydrocarbon group or an aliphatic cyclic saturated hydrocarbon group represented by the above-mentioned Ra x5 Similar bases can be cited.

[0063] Ra 101 ~Ra 103 Groups containing a carbon-carbon double bond formed by the bonding of two or more carbon atoms to each other to form a cyclic structure include, for example, cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, and methylcyclohexenyl group. Among these, cyclopentenyl group and cyclohexenyl group are preferred from the viewpoint of ease of synthesis.

[0064] Formula (R 0 -1-3) Middle, Ra' 12 and Ra' 13 Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. 12 and Ra' 13In this context, the monovalent chain-like saturated hydrocarbon group having 1 to 10 carbon atoms is the above-mentioned Ra 101 ~Ra 103 Examples include monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Ra' 12 and Ra' 13 Among these, alkyl groups having 1 to 5 carbon atoms are preferred, alkyl groups having 1 to 5 carbon atoms are more preferred, methyl groups and ethyl groups are even more preferred, and methyl groups are particularly preferred. The above Ra' 12 and Ra' 13 When a chain-like saturated hydrocarbon group represented by is substituted, the substituent may be, for example, the above-mentioned Ra x5 Similar bases can be cited.

[0065] Formula (R 0 -1-3) Middle, Ra' 14 is the formula (R 0 -1-3) is an aromatic group having a carbon-carbon bond other than the single bond formed between the α and β positions of the tertiary carbon atom, or formula (R 0 (-1-3) an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed between the α and β positions of a tertiary carbon atom (the aliphatic hydrocarbon group may have substituents). Ra' 14 The explanation for this is given by the above formula (R 0 -1) R in the middle X1 It is similar to, As aromatic groups having carbon-carbon bonds other than single bonds, groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, phenanthrene, or thiophene are preferred, groups obtained by removing one or more hydrogen atoms from benzene or thiophene are more preferred, and groups obtained by removing one or more hydrogen atoms from benzene are particularly preferred. Or, Ra' 14 The explanation for this is given by the above formula (R 0 -1) R in the middle X1 It is similar to, As the aliphatic hydrocarbon group having a carbon-carbon unsaturated bond, a linear alkenyl group or a linear alkynyl group is preferred; a linear alkenyl group is more preferred.

[0066] Ra' 14 In the above, the aromatic group having carbon-carbon bonds other than the single bond may have substituents. 14 Preferred substituents that the aromatic group in the compound may have include, for example, methyl, ethyl, propyl, hydroxyl, halogen, and alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.). Among these, halogen atoms are more preferred, and iodine atoms are particularly preferred, from the viewpoint of increasing sensitivity and reducing pattern roughness. Or, Ra' 14 In the above, the aliphatic hydrocarbon group having a carbon-carbon unsaturated bond may have substituents. 14 Preferred substituents that the aliphatic hydrocarbon group in the compound may have include, for example, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, oxo groups (=O), nitro groups, amino groups, and the like.

[0067] Below is the general formula (R 0 Specific examples of acid-dissociating groups represented by -1-1) are shown, but are not limited to these.

[0068] [ka]

[0069] [ka]

[0070] Below is the general formula (R 0 Specific examples of acid-dissociating groups represented by (1-2) are shown, but are not limited to these.

[0071] [ka]

[0072] [ka]

[0073] [ka]

[0074] Below is the general formula (R 0 Specific examples of acid-dissociating groups represented by (1-3) are shown, but are not limited to these.

[0075] [ka]

[0076] ·General formula (R 0 Acid dissociation group represented by -2) R in the above equation (a0-m0) 0 This is the following general formula (R 0 It is preferable that the acid-dissociable group is represented by (-2).

[0077] [ka] [In the formula, C* S This indicates that it is a secondary carbon atom. X2 is the aforementioned secondary carbon atom (C* S ) at the α position and the secondary carbon atom (C* S It is an aromatic group having a carbon-carbon bond other than a single bond formed with the β position of the secondary carbon atom (C* S ) at the α position and the secondary carbon atom (C* S It is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed at the β position of (the aliphatic hydrocarbon group may have substituents). Y2 R is a chain-like saturated hydrocarbon group which may have substituents, or a saturated aliphatic cyclic group which may have substituents. However, R X2 and R Y2This refers to the secondary carbon atoms (C*) bonding with each other. S ) at the α position and the secondary carbon atom (C* S A cyclic group (which may have substituents) may be formed, having a carbon-carbon bond other than the single bond formed between the β-position of ) and ). *2 indicates a bond that connects to an adjacent oxygen atom (-O-).

[0078] The above formula (R 0 -2) Medium, R X2 In the aforementioned secondary carbon atoms (C* S For an explanation of aromatic groups having carbon-carbon bonds other than the single bond formed between the α and β positions of the above formula (R 0 -1) R in the middle X1 The explanation for aromatic groups having carbon-carbon bonds other than single bonds is similar to the one given in the previous section. Among them, R X2 In this context, the aromatic group having carbon-carbon bonds other than single bonds is preferably a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle (aryl group or heteroaryl group), more preferably having 4 to 15 carbon atoms, and even more preferably having 4 to 10 carbon atoms. R X2 In this context, the aromatic groups having carbon-carbon bonds other than single bonds are preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, phenanthrene, or thiophene, more preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene, or thiophene, even more preferably groups obtained by removing one or more hydrogen atoms from benzene, naphthalene, or thiophene, particularly preferably groups obtained by removing one or more hydrogen atoms from benzene or thiophene, and most preferably groups obtained by removing one or more hydrogen atoms from benzene.

[0079] R X2 In this, aromatic groups having carbon-carbon bonds other than single bonds may have substituents. X2Preferred substituents that the aromatic group in the compound may have include, for example, a methyl group, an ethyl group, a propyl group, a hydroxyl group, a halogen atom, and an alkoxy group (such as a methoxy group, an ethoxy group, a propoxy group, or a butoxy group).

[0080] The above formula (R 0 -2) Medium, R X2 In the aforementioned secondary carbon atoms (C* S The description of an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed between the α and β positions of the above formula (R 0 -1) R in the middle X1 A similar explanation can be given for aliphatic hydrocarbon groups having carbon-carbon unsaturated bonds. Among them, R X2 In this context, the aliphatic hydrocarbon group having a carbon-carbon unsaturated bond is preferably a linear alkenyl group or a linear alkynyl group.

[0081] R X2 In this, the aliphatic hydrocarbon group having a carbon-carbon unsaturated bond may have substituents. X2 Preferred substituents that the aliphatic hydrocarbon group in the compound may have include, for example, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, oxo groups (=O), nitro groups, amino groups, and the like.

[0082] The above formula (R 0 -2) Medium, R Y2 The explanation of the chain-like saturated hydrocarbon group and saturated aliphatic cyclic group in the above formula (R 0 -1) R in the middle Y1 and R Z1 The explanations for chain-like saturated hydrocarbon groups and saturated aliphatic cyclic groups are similar to those given in the previous text. R Y2Among the chain-like saturated hydrocarbon groups, alkyl groups having 1 to 5 carbon atoms are preferred, alkyl groups having 1 to 3 carbon atoms are more preferred, methyl groups and ethyl groups are even more preferred, and methyl groups are particularly preferred. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted with substituents. Examples of such substituents include the above-mentioned Ra x5 Similar bases can be cited. R Y2 Among the saturated aliphatic cyclic groups in this context, monocyclic saturated aliphatic cyclic groups having 3 to 6 carbon atoms are preferred, and groups obtained by removing one or more hydrogen atoms from cyclopentane or cyclohexane are even more preferred. The saturated aliphatic cyclic group here may also be a saturated aliphatic heterocycle in which some of the carbon atoms constituting it are substituted with heteroatoms. Some or all of the hydrogen atoms in this saturated aliphatic cyclic group may be substituted with substituents. Examples of substituents include halogen atoms, oxo groups (=O), and -R P1 (R P1 Examples include the same as described above.

[0083] However, R X2 and R Y2 This refers to the secondary carbon atoms (C*) bonding with each other. S A cyclic group having carbon-carbon bonds other than the single bond formed between the α and β positions of ) may be formed (the cyclic group may have substituents). R X2 and R Y2 The cyclic group having carbon-carbon bonds other than single bonds, which may be formed by the bonding of these elements to one another, may be polycyclic or monocyclic, and may be alicyclic or aromatic. The alicyclic and aromatic rings may also be heterocyclic rings containing heteroatoms.

[0084] R X2 and R Y2The following are preferred as cyclic groups having carbon-carbon bonds other than single bonds, which may be formed by bonding with each other: specifically, groups obtained by removing one or more hydrogen atoms from a monocycloalkene, groups obtained by removing one or more hydrogen atoms from a ring in which some of the carbon atoms constituting the monocycloalken are substituted with heteroatoms (oxygen atoms, sulfur atoms, etc.), groups obtained by removing one or more hydrogen atoms from a monocycloalkadiene, groups obtained by removing one or more hydrogen atoms from a cycloalkene having 3 to 6 carbon atoms, and more preferably groups obtained by removing one or more hydrogen atoms from cyclopentene or cyclohexene. Alternatively, R X2 and R Y2 The cyclic group having carbon-carbon bonds other than single bonds, which may be formed by the bonding of these elements with each other, may be a group obtained by removing one or more hydrogen atoms from a fused ring. Specific examples of such fused rings include indan, tetralin, dihydrobenzofuran (coumaran), and benzodihydropyran (chroman).

[0085] R X2 and R Y2 A cyclic group having carbon-carbon bonds other than single bonds, which may be formed by the bonding of these elements to one another, may have substituents. For example, the above-mentioned Ra x5 These are some examples.

[0086] The general formula (R) described above 0 Specific examples of acid-dissociating groups represented by (2) are shown, but are not limited to these.

[0087] [ka]

[0088] R 0 The acid-dissociating group in the above general formula (R 0 An acid-dissociating group represented by -1), and the above general formula (R 0 Preferably selected from the group consisting of acid-dissociating groups represented by the above general formula (R -2), 0 Acid-dissociating group represented by -1-1), the above general formula (R 0Acid-dissociating group represented by -1-2), the above general formula (R 0 Acid-dissociating groups represented by -1-3), and the above general formula (R 0 A more preferable choice is one selected from the group consisting of acid-dissociating groups represented by (-2). R 0 In particular, in the formation of resist patterns, acid-dissociable groups having an iodine atom as a substituent are preferred from the viewpoint of increasing sensitivity and reducing pattern roughness, and acid-dissociable groups containing aromatic groups having an iodine atom as a substituent are especially preferred.

[0089] The constituent unit (a0) is preferably the constituent unit represented by the following general formula (a0-u0).

[0090] [ka] [In the formula, R X13 This represents an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. x0 X represents a divalent linking group or a single bond. 01 L represents a hydrogen atom or an alkyl group. 01 R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. 01 This is an acid-dissociable group in which a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond, and the above general formula (R 0 Acid-dissociating group represented by -1-1), the above general formula (R 0 Acid-dissociating group represented by -1-2), the above general formula (R 0 An acid-dissociating group represented by (-1-3), or the above general formula (R 0 This is an acid-dissociable group represented by (-2).

[0091] In the above equation (a0-u0), R X13In this context, the alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and the like. A halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. Fluorine is particularly preferred as the halogen atom in alkyl halides. R X13 Preferably, the elements are hydrogen atoms, alkyl groups having 1 to 5 carbon atoms, or fluorinated alkyl groups having 1 to 5 carbon atoms, with hydrogen atoms or methyl groups being the most preferred due to their industrial availability.

[0092] In the above equation (a0-u0), Ya x0 In this context, suitable divalent linking groups include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Among these, Ya x0 Preferably, the bonds are ester bonds [-C(=O)-O-, -OC(=O)-], ether bonds (-O-), linear or branched alkylene groups, aromatic hydrocarbon groups or combinations thereof, or single bonds. Among these, Ya x0 The members are more preferably ester bonds [-C(=O)-O-, -OC(=O)-], linear or branched alkylene groups, or combinations thereof, or single bonds, and even more preferably single bonds.

[0093] In the above equation (a0-u0), X 01 The alkyl group in is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Among these, X 0 The group is preferably a hydrogen atom, a methyl group, or an ethyl group, more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom.

[0094] In the above equation (a0-u0), L 01 This represents a chain or cyclic aliphatic hydrocarbon group having 1 to 12 carbon atoms. In particular, L 01 The carbon atom is preferably a chain-like aliphatic hydrocarbon group having 1 to 6 carbon atoms, or a monocyclic alicyclic hydrocarbon group having 3 to 6 carbon atoms, more preferably a chain-like or cyclic aliphatic hydrocarbon group having 1 to 3 carbon atoms, even more preferably an aliphatic hydrocarbon group having 1 to 2 carbon atoms, and particularly preferably an aliphatic hydrocarbon group having 1 carbon atom.

[0095] In the above equation (a0-u0), R 01 This is an acid-dissociable group in which a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond, and the above general formula (R 0 Acid-dissociating group represented by -1-1), the above general formula (R 0 Acid-dissociating group represented by -1-2), the above general formula (R 0 An acid-dissociating group represented by (-1-3), or the above general formula (R 0 This is an acid-dissociable group represented by (-2).

[0096] The following are specific examples of constituent units (a0), but are not limited to these. In the following equations, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0097] [ka]

[0098] [ka]

[0099] [ka]

[0100] [ka]

[0101] [ka]

[0102] The constituent unit (a0) is preferably selected from the group consisting of constituent units represented by the above chemical formulas (a0-u001) to (a0-u023), the group consisting of constituent units represented by the above chemical formulas (a0-u024) to (a0-u026), the group consisting of constituent units represented by the chemical formulas (a0-u027) to (a0-u030), and the group consisting of constituent units represented by the chemical formulas (a0-u031) to (a0-u035).

[0103] The constituent units (a0) of component (A1) may be one type or two or more types. The proportion of constituent units (a0) in component (A1) is preferably 20 to 80 mol%, more preferably 30 to 75 mol%, even more preferably 40 to 70 mol%, and particularly preferably 50 to 70 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). By setting the proportion of the constituent unit (a0) to be above the lower limit of the preferred range described above, higher sensitivity can be achieved, and lithography characteristics such as pattern roughness, exposure margin, and resolution can be easily improved. On the other hand, if it is below the upper limit of the preferred range described above, a balance can be maintained with other constituent units, resulting in good lithography characteristics in various aspects.

[0104] <<Other constituent units>> Component (A1) may have other constituent units in addition to the constituent unit (a0) described above, as necessary. Examples of such other constituent units include a constituent unit (a1) containing an acid-degradable group whose polarity increases with the action of an acid; a constituent unit (a10) represented by the general formula (a10-1) described later; a constituent unit (a2) containing a lactone-containing cyclic group; a constituent unit (a5) that generates acid upon exposure; a constituent unit (a6) that has acid diffusion controllability; and a constituent unit (a8) derived from a compound represented by the general formula (a8-1) described later. Furthermore, these other constituent units shall not include those corresponding to the constituent unit (a0) described above.

[0105] Unit of composition (a1): The constituent unit (a1) is a constituent unit that contains an acid-degradable group whose polarity increases upon the action of an acid. An "acid-degradable group" is a group that has acid-degradability, meaning that at least some of the bonds in its structure can be cleaved by the action of an acid. Examples of acid-degradable groups whose polarity increases upon the action of an acid include groups that decompose upon the action of an acid to produce polar groups. Examples of these polar groups include carboxyl groups, hydroxyl groups, amino groups, and sulfo groups (-SO3H). More specifically, examples of acid-degradable groups include groups in which the aforementioned polar group is protected by an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group).

[0106] Examples of acid-dissociable groups include those previously proposed as acid-dissociable groups for base resins used in chemically amplified resist compositions. Examples of acid-dissociable groups proposed for base resins used in chemically amplified resist compositions include acetal-type acid-dissociable groups, tertiary alkyl ester-type acid-dissociable groups, tertiary alkyloxycarbonyl acid-dissociable groups, and secondary alkyl ester-type acid-dissociable groups.

[0107] The following are specific examples of constituent units (a1). In each of the following equations, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] [ka]

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] [ka]

[0117] In the following equations, R α Rz represents a hydrogen atom, a methyl group, or a trifluoromethyl group. Rz represents a hydrogen atom, an alkyl group, a halogen atom, an alkyl halide, a hydroxyl group, or an alkoxy group.

[0118] [ka]

[0119] [ka]

[0120] [ka]

[0121] [ka]

[0122] [ka]

[0123] The constituent units (a1) of component (A1) may be one type or two or more types. The proportion of constituent units (a1) in component (A1) is preferably 5 to 40 mol%, more preferably 10 to 35 mol%, and even more preferably 15 to 30 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). By setting the proportion of the constituent unit (a1) to be above the lower limit of the preferred range described above, lithography characteristics such as sensitivity, resolution, and pattern roughness are improved. On the other hand, if it is below the upper limit of the preferred range described above, a balance can be achieved with other constituent units, resulting in good lithography characteristics in various aspects.

[0124] Unit of composition (a10): The constituent unit (a10) is a constituent unit represented by the following general formula (a10-1).

[0125] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogen having 1 to 5 carbon atoms. x1 Wa is a single bond or a divalent linking group. x1 n is an aromatic group. ax1 [ is an integer greater than or equal to 1.]

[0126] In formula (a10-1), the C1-C5 alkyl group of R is preferably a linear or branched alkyl group having 1-5 carbon atoms, specifically including methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups. The C1-C5 halogenated alkyl group is a group in which some or all of the hydrogen atoms of the C1-C5 alkyl group are substituted with halogen atoms. Fluorine atoms are particularly preferred as the halogen atoms. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, with a hydrogen atom or a methyl group being the most preferred due to their industrial availability.

[0127] In the above formula (a10-1), Ya x1 It is a single bond or a divalent linking group. In the above chemical formula, Ya x1 The divalent linking group in this is not particularly limited, but suitable examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms.

[0128] • Divalent hydrocarbon groups which may have substituents: The divalent hydrocarbon group, which may have substituents, may be an aliphatic hydrocarbon group or an aromatic group.

[0129] Aliphatic hydrocarbon groups An aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferable to be saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups containing a ring in their structure.

[0130] ...linear or branched aliphatic hydrocarbon groups The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As for the linear aliphatic hydrocarbon group, linear alkylene groups are preferred, specifically the methylene group [-CH2-], ethylene group [-(CH2)2-], trimethylene group [-(CH2)3-], tetramethylene group [-(CH2)4-], pentamethylene group [-(CH2)5-], etc. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. Preferred branched aliphatic hydrocarbon groups include branched alkylene groups, specifically alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0131] The linear or branched aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include fluorine atoms, fluorinated alkyl groups having 1 to 5 carbon atoms substituted with fluorine atoms, and carbonyl groups.

[0132] ...Aliphatic hydrocarbon groups containing a ring in their structure Examples of aliphatic hydrocarbon groups containing a ring in the structure include cyclic aliphatic hydrocarbon groups that may contain substituents containing heteroatoms in the ring structure (groups obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), groups in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group are the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. A preferred monocyclic alicyclic hydrocarbon group is a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. A preferred polycyclic alicyclic hydrocarbon group is a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Examples include decane and tetracyclododecane.

[0133] The cyclic aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and carbonyl groups. The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. As the alkoxy group used as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferred, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are more preferred, and a methoxy group and an ethoxy group are even more preferred. A fluorine atom is preferred as the halogen atom used as the substituent. Examples of halogenated alkyl groups as substituents include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. A cyclic aliphatic hydrocarbon group may have some of the carbon atoms constituting its ring structure replaced by substituents containing heteroatoms. Preferred substituents containing heteroatoms are -O-, -C(=O)-O-, -S-, -S(=O)2-, and -S(=O)2-O-.

[0134] ·Aromatic group The aromatic group is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic, polycyclic, or have substituents that substitute for the hydrogen atoms of the aromatic ring. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. The number of carbon atoms in the aromatic hydrocarbon ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 5 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents that substitute for hydrogen atoms in the aromatic hydrocarbon ring. Specific examples of aromatic hydrocarbon rings include benzene, naphthalene, anthracene, and phenanthrene. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0135] The aromatic group preferably has 4 to 30 carbon atoms, more preferably 4 to 20, even more preferably 4 to 15, and particularly preferably 4 to 12 carbon atoms. Specific examples of aromatic groups include: a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or the aromatic heterocycle (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one hydrogen atom of an aryl group or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle (aryl group or heteroaryl group) is substituted with an alkylene group (e.g., a group obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group such as a benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aforementioned aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0136] The aromatic group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic group may be substituted with substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and the like. The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Examples of the substituents include alkoxy groups, halogen atoms, and alkyl halides that substitute for hydrogen atoms on the cyclic aliphatic hydrocarbon group.

[0137] • Divalent linking groups containing heteroatoms: Examples of divalent linking groups containing heteroatoms include -O-, -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with substituents such as alkyl groups or acyl groups), -S-, -S(=O)2-, -S(=O)2-O-, and the general formula -Y 21 -OY 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -,-[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 - or -Y 21 -S(=O)2-OY 22 - is represented by the base [wherein Y 21 and Y 22 Each of these is a divalent hydrocarbon group which may independently have substituents, O is an oxygen atom, and m'' is an integer from 1 to 3. When the divalent linking group containing the heteroatom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, or -NH-C(=NH)-, the H may be substituted with substituents such as alkyl groups or acyl groups. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5. General formula-Y 21 -OY 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -,-[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 - or -Y 21 -S(=O)2-OY 22 - Middle, Y 21 and Y 22Each of these is independently a divalent hydrocarbon group which may have substituents. Examples of such divalent hydrocarbon groups are the same as those described above. Y 21 Preferably, the group is a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, even more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. Y 22 The group is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group, or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group. Formula - [Y 21 -C(=O)-O] m” -Y 22 In the base represented by -, m'' is an integer from 1 to 3, preferably 1 or 2, and more preferably 1. That is, in the formula -[Y 21 -C(=O)-O] m” -Y 22 As a base represented by -, formula -Y 21 -C(=O)-OY 22 Groups represented by - are particularly preferred. Among them, the group represented by formula -(CH2) a’ -C(=O)-O-(CH2) b’ A base represented by - is preferred. In the formula, a' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, even more preferably 1 or 2, and most preferably 1. b' is an integer from 1 to 10, preferably an integer from 1 to 8, more preferably an integer from 1 to 5, even more preferably 1 or 2, and most preferably 1.

[0138] Ya x1 Preferred members include single bonds, ester bonds [-C(=O)-O-, -OC(=O)-], ether bonds (-O-), linear or branched alkylene groups, or combinations thereof, with single bonds and ester bonds [-C(=O)-O-, -OC(=O)-] being more preferred.

[0139] In the above formula (a10-1), Wa x1 It is an aromatic group. Wa x1 The aromatic group in this case is an aromatic ring which may have substituents (n ax1 A group with 1+1 hydrogen atoms removed is an example. The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system with 4n+2 π electrons. Specifically, examples of such aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specifically, examples of aromatic heterocycles include pyridine rings and thiophene rings. Wa x1 The aromatic group in this compound preferably has 4 to 30 carbon atoms, more preferably 4 to 20, even more preferably 4 to 15, and particularly preferably 4 to 12 carbon atoms. Also, Wa x1 The aromatic group in this can be an aromatic compound containing an aromatic ring which may have two or more substituents (e.g., biphenyl, fluorene, etc.) (n ax1 Another example is a group with (+1) hydrogen atoms removed. Among the above, Wa x1 Examples include benzene, naphthalene, anthracene, or biphenyl (n ax1 A group with (+1) hydrogen atoms removed is preferred, and (n ax1 A group with (+1) hydrogen atoms removed is more preferable, and from benzene (n ax1 A group with (+1) hydrogen atoms removed is even more preferable.

[0140] Wa x1 The aromatic group in may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, and alkyl halides. Examples of alkyl groups, alkoxy groups, halogen atoms, and alkyl halides as substituents include Ya x1Examples of substituents for cyclic aliphatic hydrocarbon groups in are similar to those listed above. The substituents are preferably linear or branched alkyl groups having 1 to 5 carbon atoms, more preferably linear or branched alkyl groups having 1 to 3 carbon atoms, even more preferably ethyl or methyl groups, and particularly preferably methyl groups. x1 In this case, the aromatic group preferably has no substituents.

[0141] In the above formula (a10-1), n ax1 is an integer greater than or equal to 1, preferably an integer between 1 and 10, more preferably an integer between 1 and 5, even more preferably 1, 2, or 3, and particularly preferably 1 or 2.

[0142] The following are specific examples of the constituent unit (a10) represented by the above formula (a10-1). In the following equations, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0143] [ka]

[0144] [ka]

[0145] [ka]

[0146] The constituent units (a10) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent units (a10), but it is preferable that it has constituent units (a10). If component (A1) has constituent units (a10), the proportion of constituent units (a10) in component (A1) is preferably 20 to 80 mol%, more preferably 25 to 70 mol%, even more preferably 30 to 60 mol%, and particularly preferably 30 to 50 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). By setting the proportion of constituent unit (a10) above the lower limit, sensitivity can be more easily increased. On the other hand, by setting it below the upper limit, it becomes easier to balance it with other constituent units.

[0147] Unit of composition (a2): Component (A1) may or may not have a constituent unit (a2) containing a lactone-containing cyclic group (excluding those corresponding to constituent unit (a1)). The lactone-containing cyclic group of component (a2) is effective in improving the adhesion of the resist film to the substrate when component (A1) is used to form a resist film. Furthermore, the presence of component (a2) improves lithography characteristics, for example, by appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development.

[0148] A "lactone-containing cyclic group" refers to a cyclic group that contains a ring (lactone ring) containing -OC(=O)- within its cyclic skeleton. The lactone ring is counted as the first ring. If it consists only of a lactone ring, it is called a monocyclic group. If it also has other ring structures, it is called a polycyclic group regardless of those structures. A lactone-containing cyclic group may be a monocyclic group or a polycyclic group. Any lactone-containing cyclic group can be used in the constituent unit (a2) without any particular limitations. Specifically, examples include the groups represented by the following general formulas (a2-r-1) to (a2-r-7).

[0149] [ka] [In the formula, Ra' 21Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, or a lactone-containing cyclic group; A'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom (-O-) or a sulfur atom (-S-), an oxygen atom, or a sulfur atom, where n' is an integer from 0 to 2, and m' is 0 or 1. * indicates a bond (the same applies below).

[0150] In the general formulas (a2-r-1) to (a2-r-7), Ra' 21 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, etc. Among these, the methyl group or ethyl group is preferred, and the methyl group is particularly preferred. Ra' 21 The alkoxy group in is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the Ra' 21 Examples of alkyl groups in this context include groups formed by linking an alkyl group with an oxygen atom (-O-). Ra' 21 In this mixture, a fluorine atom is preferred as the halogen atom. Ra' 21 The halogenated alkyl group in is the Ra' 21 Examples include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. Fluorinated alkyl groups are preferred as the halogenated alkyl group, and perfluoroalkyl groups are particularly preferred.

[0151] Ra' 21 In -COOR'' and -OC(=O)R'', R'' is either a hydrogen atom, an alkyl group, or a lactone-containing cyclic group. The alkyl group in R'' can be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms. When R'' is a linear or branched alkyl group, it is preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. When R'' is a cyclic alkyl group, it is preferably 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, examples include groups obtained by removing one or more hydrogen atoms from monocycloalkanes which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, groups obtained by removing one or more hydrogen atoms from monocycloalkanes such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Examples include groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as decane and tetracyclododecane. Examples of lactone-containing cyclic groups in R'' include those similar to those represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above. Ra' 21 The hydroxyalkyl group in is preferably one having 1 to 6 carbon atoms, specifically the Ra' 21 Examples include groups in which at least one hydrogen atom of the alkyl group is substituted with a hydroxyl group.

[0152] Ra' 21 Among the above, it is preferable that each is independently a hydrogen atom or a cyano group.

[0153] In the general formulas (a2-r-2), (a2-r-3), and (a2-r-5) above, the alkylene group having 1 to 5 carbon atoms in A'' is preferably a linear or branched alkylene group, such as a methylene group, ethylene group, n-propylene group, isopropylene group, etc. If the alkylene group contains an oxygen atom or a sulfur atom, specific examples include a group in which -O- or -S- is interposed at the end or between carbon atoms of the alkylene group, such as -O-CH2-, -CH2-O-CH2-, -S-CH2-, -CH2-S-CH2-, etc. As A'', an alkylene group having 1 to 5 carbon atoms or -O- is preferred, an alkylene group having 1 to 5 carbon atoms is more preferred, and a methylene group is most preferred.

[0154] The following are specific examples of groups represented by the general formulas (a²-r-1) to (a²-r-7).

[0155] [ka]

[0156] [ka]

[0157] Among the constituent units (a2), those derived from acrylic acid esters in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent are preferred. The constituent unit (a2) is preferably a constituent unit represented by the following general formula (a2-1).

[0158] [ka] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogen having 1 to 5 carbon atoms. 21 It is a single bond or a divalent linking group. 21The R' is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, where R' represents a hydrogen atom or a methyl group. However, La 21 If -O-, Ya 21 It does not become -CO-. 21 It is a lactone-containing cyclic group.

[0159] In formula (a2-1) above, R is the same as above. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and a hydrogen atom or a methyl group is particularly preferred due to their industrial availability.

[0160] In the above formula (a2-1), Ya 21 The divalent linking group in this is not particularly limited, but preferred examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. 21 The divalent linking group in the above general formula (a10-1) is Ya x1 Examples include divalent linking groups similar to those in [the relevant context].

[0161] Ya 21 Preferably, the group is a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0162] In the above formula (a2-1), Ya 21 It is a single bond, La 21 It is preferable that it be -COO- or -OCO-.

[0163] In the above formula (a2-1), Ra 21 It is a lactone-containing cyclic group. Ra 21 Suitable lactone-containing cyclic groups in this compound include those represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above.

[0164] The constituent units (a2) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent units (a2). If component (A1) has constituent units (a2), the proportion of constituent units (a2) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and even more preferably 5 to 20 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). If the proportion of constituent unit (a2) is set above a preferred lower limit, the effects of including constituent unit (a2) are fully obtained due to the effects described above, and if it is below the upper limit, a balance can be achieved with other constituent units, resulting in good lithography characteristics.

[0165] Unit of composition (a5): Component (A1) may or may not have a constituent unit (a5) that generates acid upon exposure. Known constituent units (a5) can be used. Having constituent unit (a5) makes it easier for the acid generated upon exposure to be uniformly distributed within the resist film. Examples of constituent unit (a5) include a constituent unit containing the structure described in component (B) below. For example, a constituent unit containing a structure represented by any of the general formulas (b-1) to (b-3) below can be used. Suitable constituent units (a5) include, for example, the constituent unit represented by the following general formula (a5-1).

[0166] [ka] [In the formula, R m This is an alkyl group having 1 to 5 carbon atoms, an alkyl halide having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. 50 This is a divalent linking group or a single bond. 50 n is a divalent hydrocarbon group which may have substituents. a5 is an integer between 0 and 2. 51 It is a divalent linking group. 5This is a divalent linking group that may have a heteroatom, or a single bond. 51 and Ra 52 Each of these is independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group. n5 is an integer from 1 to 4. m is an integer of 1 or more, and M' m+ This is an onium cation with a valence of m.

[0167] {Anion Division} In the above formula (a5-1), R m These are alkyl groups having 1 to 5 carbon atoms, alkyl halides having 1 to 5 carbon atoms, halogen atoms, or hydrogen atoms. R m The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. A halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. Fluorine is particularly preferred as the halogen atom in alkyl halides. R m Preferably, the elements are hydrogen atoms, alkyl groups having 1 to 5 carbon atoms, or fluorinated alkyl groups having 1 to 5 carbon atoms, with hydrogen atoms or methyl groups being the most preferred due to their industrial availability.

[0168] In the above formula (a5-1), La 50 This is a divalent linking group or a single bond. La 50 The divalent linking group in is not particularly limited, but preferred examples include a divalent hydrocarbon group which may have substituents, and a divalent linking group which contains a heteroatom, respectively. x1 This is similar to the divalent linking groups exemplified in the above, such as divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Among the above, La 50 Preferably, the bonds are ester bonds [-C(=O)-O-, -OC(=O)-], ether bonds (-O-), linear or branched alkylene groups, aromatic hydrocarbon groups or combinations thereof, or single bonds. Among these, La 5 As such, ester bonds [-C(=O)-O-, -OC(=O)-] and single bonds are more preferable, and ester bonds [-C(=O)-O-, -OC(=O)-] are even more preferable.

[0169] In the above formula (a5-1), Ra 50 This is a divalent hydrocarbon group which may have substituents. Ra 50 The divalent hydrocarbon group in this expression may be an aliphatic hydrocarbon group or an aromatic group.

[0170] ··Ra 50 Aliphatic hydrocarbon groups in The aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferred to be saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups containing a ring in their structure.

[0171] ...linear or branched aliphatic hydrocarbon groups The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As for the linear aliphatic hydrocarbon group, linear alkylene groups are preferred, specifically the methylene group [-CH2-], ethylene group [-(CH2)2-], trimethylene group [-(CH2)3-], tetramethylene group [-(CH2)4-], pentamethylene group [-(CH2)5-], etc. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. Preferred branched aliphatic hydrocarbon groups include branched alkylene groups, specifically alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0172] The linear or branched aliphatic hydrocarbon group described above may or may not have substituents. Examples of substituents include fluorine atoms, fluorinated alkyl groups having 1 to 5 carbon atoms substituted with fluorine atoms, and carbonyl groups.

[0173] ...Aliphatic hydrocarbon groups containing a ring in their structure Examples of aliphatic hydrocarbon groups containing a ring in the structure include cyclic aliphatic hydrocarbon groups that may contain substituents containing heteroatoms in the ring structure (groups from which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), groups in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group are the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. A preferred monocyclic alicyclic hydrocarbon group is a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. A preferred polycyclic alicyclic hydrocarbon group is a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Examples include decane and tetracyclododecane.

[0174] The cyclic aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and carbonyl groups. The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. As the alkoxy group used as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferred, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are more preferred, and a methoxy group and an ethoxy group are most preferred. Examples of halogen atoms used as substituents include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, and the like, with fluorine atoms being preferred. Examples of halogenated alkyl groups as substituents include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. A cyclic aliphatic hydrocarbon group may have some of the carbon atoms constituting its ring structure replaced by substituents containing heteroatoms. Preferred substituents containing heteroatoms are -O-, -C(=O)-O-, -S-, -S(=O)2-, and -S(=O)2-O-.

[0175] ··Ra 50 Aromatic group in The aromatic group is a group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic, polycyclic, or have substituents that substitute for the hydrogen atoms of the aromatic ring. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. The number of carbon atoms in the aromatic hydrocarbon ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 5 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents that substitute for hydrogen atoms in the aromatic hydrocarbon ring. Specific examples of aromatic hydrocarbon rings include benzene, naphthalene, anthracene, and phenanthrene. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0176] The aromatic group preferably has 4 to 30 carbon atoms, more preferably 4 to 20, even more preferably 4 to 15, and particularly preferably 4 to 12 carbon atoms. Specific examples of aromatic groups include: a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or the aromatic heterocycle (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one hydrogen atom of an aryl group or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or the aromatic heterocycle (aryl group or heteroaryl group) is substituted with an alkylene group (e.g., a group obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group such as a benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aforementioned aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0177] The aromatic group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic group may be substituted with substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and the like. The alkyl group used as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Examples of the substituents include alkoxy groups, halogen atoms, and alkyl halogens that substitute for hydrogen atoms on the cyclic aliphatic hydrocarbon group.

[0178] In the above formula (a5-1), n a5 This is an integer between 0 and 2. Among the above, 50 The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group containing a ring in its structure, more preferably a cyclic aliphatic hydrocarbon group which may contain substituents containing heteroatoms in its ring structure, and even more preferably an alicyclic hydrocarbon group which may have substituents and is a polycyclic or monocyclic group. Alternatively, among the above, Ra 50 Aromatic groups are preferred.

[0179] n a5 If it is 2, then 2 Ra 50 These may all be alicyclic hydrocarbon groups which may have substituents, or they may all be aromatic groups which may have substituents, or they may be a combination of alicyclic hydrocarbon groups which may have substituents and aromatic groups which may have substituents.

[0180] In the above formula (a5-1), La 51 It is a divalent linking group. La 51Examples of divalent linking groups in this context include non-hydrocarbon oxygen-containing linking groups such as oxygen atoms (ether bond: -O-), ester bonds (-C(=O)-O-), oxycarbonyl groups (-OC(=O)-), amide bonds (-C(=O)-NH-), carbonyl groups (-C(=O)-), and carbonate bonds (-OC(=O)-O-); and combinations of these non-hydrocarbon oxygen-containing linking groups with alkylene groups. A sulfonyl group (-SO2-) may be further linked to this combination. Examples of such divalent linking groups include the linking groups represented by the following general formulas (L-al-1) to (L-al-8). Note that in the following general formulas (L-al-1) to (L-al-8), Ra in formula (a5-1) above 50 The combination with this is V' in the following general formulas (L-al-1)~(L-al-8). 101 That is the case.

[0181] [ka] [In the formula, V' 101 V' is a single bond or an alkylene group with 1 to 5 carbon atoms. 102 It is a divalent saturated hydrocarbon group with 1 to 30 carbon atoms.

[0182] V' 102 The divalent saturated hydrocarbon group in is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0183] V' 101 and V' 102 The alkylene group in this product may be a linear alkylene group or a branched alkylene group, but a linear alkylene group is preferred. V' 101 and V' 102Specifically, the alkylene groups in these include: methylene group [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; ethylene group [-CH2CH2-]; -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2 Examples include alkylethylene groups such as -CH2CH2CH2-; trimethylene groups (n-propylene groups) [-CH2CH2CH2-]; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; tetramethylene groups [-CH2CH2CH2CH2-]; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-; and pentamethylene groups [-CH2CH2CH2CH2CH2-]. Also, oshiV' 101 or V' 102 Some of the methylene groups in the alkylene group may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a divalent group obtained by removing one more hydrogen atom from a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group), and more preferably a cyclohexylene group, a 1,5-adamantilene group, or a 2,6-adamantilene group.

[0184] La 51 Preferably, the linking group is a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, more preferably the linking groups represented by the above formulas (L-al-1) to (L-al-5) and (L-al-8), and even more preferably the linking group represented by the above formula (L-al-3) or (L-al-8).

[0185] In the above formula (a5-1), Ya 5 This is a divalent linking group that may have a heteroatom, or a single bond. Ya 5 The divalent linking group in this is not particularly limited, but preferred examples include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Ya 5 In the above, the divalent hydrocarbon group which may have substituents, and the divalent linking group which contains a heteroatom, are as follows: x1 This is similar to the divalent linking groups exemplified in the above, such as divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Among the above, Ya 5 The alkylene group is preferably a linear or branched alkylene group, or a single bond, with a single bond being more preferable.

[0186] In the above formula (a5-1), Ra 51 and Ra 52 Each of these is independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group. Ra 51 and Ra 52 The fluorinated alkyl groups in this compound are preferably linear or branched fluorinated alkyl groups having 1 to 5 carbon atoms, with a trifluoromethyl group being more preferred. In the above formula (a5-1), SO3 - Ra bonds to the adjacent carbon atom. 51 and Ra 52 From the viewpoint of acid strength, it is preferable that at least one of these atoms is a fluorine atom.

[0187] In the above formula (a5-1), n5 is an integer from 1 to 4, and is preferably 1, 2, or 3.

[0188] {cation part} In the above formula (a5-1), M' m+ This represents an m-valent onium cation. Among these, M' m+ The sulfonium cation and iodonium cation are preferred. m is an integer of 1 or more. Preferred cation portion ((M' m+ ) 1 / m Examples of these include organic cations represented by the following general formulas (ca-1) to (ca-3).

[0189] [ka] [In the formula, R 201 ~R 207 Each of these independently represents an optionally substituted aryl group, an optionally substituted alkyl group, or an optionally substituted alkenyl group. 201 ~R 203 , R 206 ~R 207 These atoms may bond to each other to form a ring with the sulfur atom in the formula. 208 ~R 209 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 210 This is an optionally substituted aryl group, an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted -SO2- containing cyclic group. 201 This represents -C(=O)- or -C(=O)-O-.

[0190] In the above general formulas (ca-1) to (ca-3), R 201 ~R 207 Examples of aryl groups in this context include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. R 201 ~R 207 The alkyl group in this is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. R 201 ~R 207 The alkenyl group in this compound preferably has 2 to 10 carbon atoms. R 201 ~R 207 , and R 210 Examples of substituents that may be present include alkyl groups, halogen atoms, alkyl halides, carbonyl groups, cyano groups, amino groups, aryl groups, and groups represented by the following general formulas (ca-r-1) to (ca-r-7).

[0191] [ka] [In the formula, R' 201Each of these is independently a hydrogen atom, an optionally substituted cyclic group, an optionally substituted linear alkyl group, or an optionally substituted linear alkenyl group.

[0192] Cyclic groups that may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not possess aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferred to be saturated.

[0193] R' 201 In this context, an aromatic group is a group that has at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic, polycyclic, or have substituents that substitute for the hydrogen atoms of the aromatic ring. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. The number of carbon atoms in the aromatic hydrocarbon ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 5 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents that substitute for hydrogen atoms in the aromatic hydrocarbon ring. Specific examples of aromatic hydrocarbon rings include benzene, naphthalene, anthracene, and phenanthrene. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0194] The number of carbon atoms in the aromatic group is preferably 4 to 30, more preferably 4 to 25, even more preferably 4 to 20, particularly preferably 4 to 15, and most preferably 4 to 10. R' 201Specific examples of aromatic groups in this context include groups obtained by removing one hydrogen atom from the aromatic ring (aryl groups: e.g., phenyl group, naphthyl group, etc.), and groups in which one of the hydrogen atoms of the aromatic ring is replaced by an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group (alkyl chain in arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0195] R' 201 In this context, cyclic aliphatic hydrocarbon groups include aliphatic hydrocarbon groups that contain a ring in their structure. Examples of aliphatic hydrocarbon groups containing a ring in this structure include alicyclic hydrocarbon groups (groups from which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. A preferred monocyclic alicyclic hydrocarbon group is a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. A preferred polycyclic alicyclic hydrocarbon group is a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 30 carbon atoms. Among these, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Polycycloalkanes having a cross-linked ring polycyclic skeleton such as decane and tetracyclododecane; polycycloalkanes having a fused ring polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferred.

[0196] Among them, R' 201 The cyclic aliphatic hydrocarbon group in is preferably a monocycloalkane or polycycloalkane from which one or more hydrogen atoms have been removed, more preferably a polycycloalkane from which one hydrogen atom has been removed, with adamantyl and norbornyl groups being particularly preferred, and the adamantyl group being the most preferred.

[0197] The linear or branched aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As for the linear aliphatic hydrocarbon group, linear alkylene groups are preferred, specifically the methylene group [-CH2-], ethylene group [-(CH2)2-], trimethylene group [-(CH2)3-], tetramethylene group [-(CH2)4-], pentamethylene group [-(CH2)5-], etc. Preferred branched aliphatic hydrocarbon groups include branched alkylene groups, specifically alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0198] Also, R' 201The cyclic hydrocarbon group in this formula may contain heteroatoms, such as heterocycles. Specifically, examples include lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above, -SO2--containing cyclic groups represented by the general formulas (b5-r-1) to (b5-r-4) described below, and heterocyclic groups represented by the chemical formulas (r-hr-1) to (r-hr-16) below.

[0199] [ka]

[0200] R' 201 Examples of substituents on the cyclic group include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, and nitro groups. As alkyl groups used as substituents, alkyl groups having 1 to 5 carbon atoms are preferred, with methyl, ethyl, propyl, n-butyl, and tert-butyl groups being the most preferred. As the substituent, an alkoxy group having 1 to 5 carbon atoms is preferred, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are more preferred, and a methoxy group and an ethoxy group are most preferred. As the halogen atom used as a substituent, a fluorine atom is preferred. Examples of alkyl halides used as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms are substituted with the halogen atoms. A carbonyl group as a substituent is a group that substitutes for a methylene group (-CH2-) that constitutes a cyclic hydrocarbon group.

[0201] Chain-like alkyl groups that may have substituents: R' 201 The chain-like alkyl group may be either linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, examples include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

[0202] A chain-like alkenyl group which may have substituents: R' 201 The linear alkenyl group may be linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, even more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Examples of branched alkenyl groups include 1-methylvinyl groups, 2-methylvinyl groups, 1-methylpropenyl groups, and 2-methylpropenyl groups. Among the above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0203] R' 201 Examples of substituents in the chain-like alkyl or alkenyl group include alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, amino groups, and the above R' 201 Examples include cyclic groups in this context.

[0204] R' 201In addition to those mentioned above, the optionally substituted cyclic groups, optionally substituted linear alkyl groups, or optionally substituted linear alkenyl groups also include tertiary alkyl ester type acid-dissociable groups as optionally substituted cyclic groups or optionally substituted linear alkyl groups.

[0205] Among them, R' 201 The cyclic group is preferably a cyclic group which may have substituents, and more preferably a cyclic hydrocarbon group which may have substituents. More specifically, preferred groups include, for example, a phenyl group, a naphthyl group, a polycycloalkane from which one or more hydrogen atoms have been removed; lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above; and -SO2--containing cyclic groups represented by the general formulas (b5-r-1) to (b5-r-4) mentioned below.

[0206] In the above general formulas (ca-1) to (ca-3), R 201 ~R 203 , R 206 ~R 207 When these atoms bond to each other and form a ring with the sulfur atom in the formula, they may be heteroatoms such as sulfur, oxygen, or nitrogen atoms, or carbonyl groups, -SO-, -SO2-, -SO3-, -COO-, -CONH-, or -N(R N )-(applicable R N is an alkyl group having 1 to 5 carbon atoms. ) may be bonded via functional groups such as ). The formed ring preferably has 3 to 10 members, and particularly preferably 5 to 7 members, including the sulfur atom in its ring skeleton. Specific examples of the formed ring include, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthlene ring, a phenoxatiyne ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.

[0207] R 208 ~R 209Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. If an alkyl group is formed, it may bond with other elements to form a ring.

[0208] R 210 This is an optionally substituted aryl group, an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted -SO2- containing cyclic group. R 210 Examples of aryl groups in this context include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. R 210 The alkyl group in this is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. R 210 The alkenyl group in this compound preferably has 2 to 10 carbon atoms. R 210 In this context, any -SO2-containing cyclic group can be used without particular limitations. Specifically, groups represented by the following general formulas (b5-r-1) to (b5-r-4) are examples, with "-SO2-containing polycyclic groups" being preferred, and the group represented by general formula (b5-r-1) being more preferred.

[0209] [ka] [In the formula, Rb' 51 Each of the following is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, or a -SO2--containing cyclic group; B'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom, and n' is an integer from 0 to 2. * indicates a bond.

[0210] In the general formulas (b5-r-1) to (b5-r-2) above, B'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom. B'' is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and even more preferably a methylene group.

[0211] In the above general formulas (b5-r-1) to (b5-r-4), Rb' 51 Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group, and among these, each is preferably independently a hydrogen atom or a cyano group.

[0212] Below are specific examples of the groups represented by the general formulas (b5-r-1) to (b5-r-4). In the formulas, "Ac" indicates an acetyl group.

[0213] [ka]

[0214] [ka]

[0215] [ka]

[0216] Specific examples of suitable cations represented by the above formula (ca-1) include the cations represented by the following chemical formulas.

[0217] [ka]

[0218] [ka]

[0219] [ka] [In the formula, g1, g2, and g3 represent the number of repetitions, where g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 1 to 20.]

[0220] [ka]

[0221] [ka]

[0222] [ka] [In the formula, R” 201 is a hydrogen atom or a substituent, and the substituent is the aforementioned R 201 ~R 207 and R 210 These are the same as those listed as substituents that may be present.

[0223] [ka]

[0224] [ka]

[0225] [ka]

[0226] Suitable cations represented by the formula (ca-2) include, specifically, diphenyliodonium cation and bis(4-tert-butylphenyl)iodonium cation.

[0227] Specific examples of suitable cations represented by the above formula (ca-3) include the cations represented by the following formulas (ca-3-1) to (ca-3-6).

[0228] [ka]

[0229] In the above formula (a5-1), the cation portion ((M' m+ ) 1 / m Preferred cations include sulfonium cations, and more preferably at least one selected from the group consisting of cations represented by the general formulas (Ca-1) to (Ca-3), and among these, the cation represented by the general formula (Ca-1) is even more preferred, and specifically, examples include cations represented by the formulas (Ca-1-1) to (Ca-1-104).

[0230] Particularly from the viewpoint of increasing sensitivity and reducing roughness, the cation portion is preferably a cation represented by the formula (ca-1), preferably having electron-withdrawing groups such as halogen atoms, alkyl halides, and sulfonyl groups as substituents, preferably an m-valent organic cation having a halogen atom as a substituent, more preferably having at least one selected from the group consisting of halogen atoms and alkyl halides, particularly preferably having at least one selected from the group consisting of fluorine atoms, iodine atoms, bromine atoms, and alkyl fluorides, and most preferably having at least one selected from the group consisting of fluorine atoms, iodine atoms, and alkyl fluorides. The alkyl halide may be linear or branched. The alkyl halide preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 or 2 carbon atoms. The alkyl halide preferably has a trifluoromethyl group.

[0231] Cation part ((M' m+ ) 1 / mThe cation is particularly preferably represented by the following general formula (ca-h-1).

[0232] [ka] [In the formula, Rf 201 ~Rf 203 Each of these independently represents an optionally substituted aryl group, an optionally substituted alkyl group, or an optionally substituted alkenyl group. 201 ~Rf 203 These atoms may bond to each other to form a ring with the sulfur atom in the formula. However, Rf 201 ~Rf 203 At least one of them has at least one halogen atom.

[0233] Rf in the above equation (ca-h-1) 201 ~Rf 203 R in the above formula (ca-1) is 201 ~R 203 The same applies to each of the above. However, Rf 201 ~Rf 203 At least one of the components has at least one halogen atom. The halogen atom is preferably at least one selected from the group consisting of fluorine, iodine, and bromine atoms, and more preferably at least one selected from the group consisting of fluorine and iodine atoms. The cation represented by formula (ca-h-1) preferably contains three or more halogen atoms, more preferably four or more halogen atoms, even more preferably five or more halogen atoms, and particularly preferably six or more halogen atoms. Rf 201 ~Rf 203 Any one of them may have three or more halogen atoms, Rf 201 ~Rf 203 The total number of halogen atoms contained in it may be three or more. Rf 201 ~Rf 203The substituent is preferably an aryl group which may have substituents, and more preferably an aryl group which has substituents containing a halogen atom. The substituent containing a halogen atom is preferably at least one selected from the group consisting of halogen atoms and alkyl halides, more preferably at least one selected from the group consisting of fluorine atoms, iodine atoms and alkyl fluorides, even more preferably at least one selected from the group consisting of fluorine atoms, iodine atoms and trifluoromethyl groups, and particularly preferably at least one selected from the group consisting of fluorine atoms and iodine atoms. As such a cation portion, a cation selected from the group consisting of cations represented by the chemical formulas (ca-1-44) and (ca-1-71) to (ca-1-104), respectively, is particularly preferred.

[0234] The following are some preferred examples of the constituent unit (a5). In the following equation, R α m and M' represent a hydrogen atom, a methyl group, or a trifluoromethyl group. m+ These are m and M' in the general formula (a5-1) above. m+ It is similar to that.

[0235] [ka]

[0236] [ka]

[0237] [ka]

[0238] (A1) The constituent units (a5) of component (A1) may be one type or two or more types. If component (A1) has constituent units (a5), the proportion of constituent units (a5) in component (A1) is preferably 2 to 30 mol%, more preferably 5 to 25 mol%, and even more preferably 10 to 20 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). If the proportion of the constituent unit (a5) is above the lower limit of the preferred range mentioned above, it becomes easier to achieve further increases in sensitivity and resolution. On the other hand, if it is below the upper limit of the preferred range mentioned above, it becomes easier to balance it with the other constituent units.

[0239] Unit of composition (a6): The constituent unit (a6) is a constituent unit that has acid diffusion control properties. Component (A1) may or may not contain constituent unit (a6). Known constituent units can be used for constituent unit (a6). Examples of constituent unit (a6) include constituent units containing the structures described in components (D1) and (D2) below. For example, a constituent unit containing a structure represented by any of the general formulas (d1-1) to (d1-3) below can be used.

[0240] The constituent units (a6) of component (A1) may be one type or two or more types. If component (A1) has constituent units (a6), the proportion of constituent units (a6) in component (A1) is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and even more preferably 3 to 10 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1). If the proportion of the constituent unit (a6) is above the lower limit of the preferred range mentioned above, it becomes easier to achieve even higher sensitivity. On the other hand, if it is below the upper limit of the preferred range mentioned above, it becomes easier to balance it with the other constituent units.

[0241] Unit of composition (a8): The constituent unit (a8) is a constituent unit derived from the compound represented by the following general formula (a8-1). Component (A1) may or may not have the constituent unit (a8).

[0242] [ka] [In the formula, W 2 This is a polymerizable group-containing group. x2 is a single bond or (n ax2 It is a linking group with a +1 valence. x2 and W 2 It may form a fused ring with R. 1 R is a fluorinated alkyl group having 1 to 12 carbon atoms. 2 R is an organic group having 1 to 12 carbon atoms, which may contain a fluorine atom, or a hydrogen atom. 2 and Ya x2 These may be bonded to each other to form a ring structure. ax2 [This is an integer between 1 and 3.]

[0243] W 2 In the context of polymerizable group-containing groups, "polymerizable group" refers to a group that enables a compound containing a polymerizable group to polymerize by radical polymerization or the like, and includes, for example, a group containing multiple bonds between carbon atoms, such as an ethylenic double bond.

[0244] The polymerizable group-containing group may be a group composed solely of a polymerizable group, or a group composed of a polymerizable group and other groups other than the polymerizable group. Examples of other groups other than the polymerizable group include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Examples of polymerizable groups include those with the chemical formula: C(R X11 )(R X12 )=C(R X13 )-Ya x0 The group represented by - is preferably mentioned. In this chemical formula, R X11 , R X12 and R X13 These are, respectively, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Ya x0 It is a single bond or a divalent linking group.

[0245] Ya x2 and W 2 The condensed ring formed by these is W2 Polymerizable groups of the site and Ya x2 The condensed ring formed by and W 2 Other groups besides the polymerizable group of the site and Ya x2 A condensed ring formed by these is one example. Ya x2 and W 2 The fused ring formed by these two components may have substituents.

[0246] The following are specific examples of constituent units (a8). In the following formula, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0247] [ka]

[0248] Among the examples above, the constituent unit (a8) is preferably at least one selected from the group consisting of constituent units represented by the chemical formulas (a8-1-01) to (a8-1-04), (a8-1-06), (a8-1-08), (a8-1-09), and (a8-1-10), and more preferably at least one selected from the group consisting of constituent units represented by the chemical formulas (a8-1-01) to (a8-1-04) and (a8-1-09).

[0249] The constituent units (a8) of component (A1) may be one type or two or more types. Component (A1) may or may not have constituent units (a8). The proportion of constituent units (a8) in component (A1) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and even more preferably 5 to 20 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0250] The (A1) component contained in the resist composition may be used alone or in combination of two or more types.

[0251] In the resist composition of this embodiment, component (A1) has a constituent unit (a0), and a polymer compound having a repeating structure of constituent units (a0) and (a10) is preferably mentioned. (A1) Specifically, examples of components include polymer compounds consisting of a repeating structure of constituent unit (a0) and constituent unit (a10), polymer compounds consisting of a repeating structure of constituent unit (a0) and constituent unit (a10) and constituent unit (a8), polymer compounds consisting of a repeating structure of constituent unit (a0) and constituent unit (a10) and constituent unit (a2), and polymer compounds consisting of a repeating structure of constituent unit (a0) and constituent unit (a10) and constituent unit (a5).

[0252] In a polymer compound consisting of a repeating structure of constituent units (a0) and constituent units (a10), the proportion of constituent units (a0) is preferably 20 to 80 mol%, more preferably 30 to 75 mol%, even more preferably 40 to 70 mol%, and still more preferably 50 to 70 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of constituent units (a10) in the polymer compound is preferably 20 to 80 mol%, more preferably 25 to 70 mol%, even more preferably 30 to 60 mol%, and particularly preferably 30 to 50 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0253] In a polymer compound having a repeating structure of constituent unit (a0), constituent unit (a10), and other constituent units (any of constituent units (a8), (a2), or (a5)), the proportion of constituent unit (a0) is preferably 20 to 80 mol%, more preferably 30 to 75 mol%, even more preferably 40 to 70 mol%, and still more preferably 50 to 70 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of constituent units (a10) in the polymer compound is preferably 15 to 50 mol%, more preferably 20 to 45 mol%, even more preferably 25 to 40 mol%, and particularly preferably 25 to 35 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of other constituent units (each of constituent units (a8), (a2), or (a5)) in the polymer compound is preferably 5 to 30 mol%, more preferably 5 to 25 mol%, even more preferably 5 to 20 mol%, and particularly preferably 5 to 15 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0254] Such component (A1) can be produced by dissolving monomers that induce each constituent unit in a polymerization solvent and then adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate (e.g., V-601) to the mixture and polymerizing it. Alternatively, such component (A1) can be produced by dissolving a monomer that induces the constituent unit (a0) (i.e., a compound represented by the general formula (a0-m0)) and a monomer that induces any constituent unit (e.g., constituent unit (a10), or other constituent units) in a polymerization solvent, adding a radical polymerization initiator as described above to carry out polymerization, and then performing a deprotection reaction. Furthermore, during polymerization, a chain transfer agent such as HS-CH2-CH2-CH2-C(CF3)2-OH may be used in combination to introduce a -C(CF3)2-OH group at the terminal. Copolymers in which a hydroxyalkyl group, in which some of the hydrogen atoms of the alkyl group are replaced with fluorine atoms, are introduced are effective in reducing development defects and LER (line edge roughness: uneven unevenness of the line sidewall).

[0255] The weight-average molecular weight (Mw) of component (A1) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 3,000 to 40,000, and even more preferably 4,000 to 30,000. If the Mw of component (A1) is below the preferred upper limit of this range, it has sufficient solubility in the resist solvent for use as a resist, and if it is above the preferred lower limit of this range, it has good dry etching resistance and a good cross-sectional shape of the resist pattern. (A1) The degree of dispersion of component (Mw / Mn) is not particularly limited, but is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.0 to 2.0. Mn represents the number-average molecular weight.

[0256] (A2) About the ingredients The resist composition of this embodiment may also include, as component (A), a base component (hereinafter referred to as "component (A2)") that does not correspond to component (A1) and whose solubility in the developer changes due to the action of an acid. (A2) The component is not particularly limited and can be arbitrarily selected from a large number of components that have been conventionally known as base components for chemically amplified resist compositions. (A2) Component may be a single high-molecular-weight compound or a low-molecular-weight compound, or two or more may be used in combination.

[0257] The proportion of component (A1) in component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 75% by mass or more, and may be 100% by mass, based on the total mass of component (A). When the proportion is 25% by mass or more, high sensitivity can be achieved in the formation of the resist pattern, and lithography characteristics such as pattern roughness, exposure margin and resolution can be easily improved.

[0258] In the resist composition of this embodiment, the content of component (A) may be adjusted according to the resist film thickness to be formed.

[0259] <Other ingredients> The resist composition of this embodiment may further contain other components in addition to the above-described component (A). Examples of such other components include the following components (B), (D), (E), (F), and (S).

[0260] ≪Acid Generating Agent Component (B)≫ The resist composition of this embodiment may further contain an acid-generating agent component (B) that generates acid upon exposure. (B) The component is not particularly limited, and any acid generators previously proposed for chemically amplified resist compositions can be used. Examples of such acid generators include onium salt-based acid generators such as iodonium salts and sulfonium salts, oximesulfonate-based acid generators; diazomethane-based acid generators such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl) diazomethanes; nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators, among many others. The form in which component (B) is contained may be in the form of a compound, or it may be incorporated into component (A1) as the above-mentioned constituent unit (a5), or it may be in both of these forms.

[0261] Examples of onium salt-based acid generators include the compound represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), the compound represented by the general formula (b-2) (hereinafter also referred to as "component (b-2)"), or the compound represented by the general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0262] [ka] [In the formula, R 101 and R 104 ~R 108 Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. 104 and R 105 These may be bonded to each other to form a ring structure. 102 This is a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. 101 This is a divalent linking group or single bond containing an oxygen atom. 101 ~V 103 Each of these is independently a single bond, an alkylene group, or a fluorinated alkylene group. However, Y 101 and V 101 L cannot be a single bond at the same time. 101 ~L 102Each of these is independently either a single bond or an oxygen atom. 103 ~L 105 These are, independently, single bonds, -CO-, or -SO2-. m is an integer greater than or equal to 1, and M' m+ This is an onium cation with a valence of m.

[0263] {Anion Division} • Anion in component (b-1) In formula (b-1), R 101 This is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents.

[0264] Cyclic groups that may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group is preferably saturated.

[0265] R 101 The aromatic group in this context is a group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system with 4n+2 π electrons, and may be monocyclic, polycyclic, or have substituents that substitute for the hydrogen atoms of the aromatic ring. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are replaced by heteroatoms. The number of carbon atoms in the aromatic hydrocarbon ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 5 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents that substitute for hydrogen atoms in the aromatic hydrocarbon ring. Specific examples of aromatic hydrocarbon rings include benzene, naphthalene, anthracene, and phenanthrene. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0266] The number of carbon atoms in the aromatic group is preferably 4 to 30, more preferably 4 to 25, even more preferably 4 to 20, particularly preferably 4 to 15, and most preferably 4 to 10. R 101 Specific examples of aromatic groups in this context include groups obtained by removing one hydrogen atom from the aromatic ring (aryl groups: for example, phenyl groups, naphthyl groups, etc.), and groups in which one of the hydrogen atoms of the aromatic ring is replaced by an alkylene group (for example, benzyl groups, phenethyl groups, 1-naphthylmethyl groups, etc.). The number of carbon atoms in the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0267] R 101 In this context, cyclic aliphatic hydrocarbon groups include aliphatic hydrocarbon groups that contain a ring in their structure. Examples of aliphatic hydrocarbon groups containing a ring in this structure include alicyclic hydrocarbon groups (groups from which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. A preferred monocyclic alicyclic hydrocarbon group is a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, etc. A preferred polycyclic alicyclic hydrocarbon group is a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 30 carbon atoms. Among these, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Polycycloalkanes having a cross-linked ring polycyclic skeleton such as decane and tetracyclododecane; polycycloalkanes having a fused ring polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferred.

[0268] Among them, R 101 The cyclic aliphatic hydrocarbon group in is preferably a monocycloalkane or polycycloalkane from which one or more hydrogen atoms have been removed, more preferably a polycycloalkane from which one hydrogen atom has been removed, even more preferably an adamantyl group or a norbornyl group, and particularly preferably an adamantyl group.

[0269] The linear aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 1 to 10 carbon atoms, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. Examples of linear aliphatic hydrocarbon groups include linear alkylene groups, specifically methylene groups [-CH2-], ethylene groups [-(CH2)2-], trimethylene groups [-(CH2)3-], tetramethylene groups [-(CH2)4-], pentamethylene groups [-(CH2)5-], and the like. The branched aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 2 to 10 carbon atoms, more preferably 3 to 6, even more preferably 3 or 4, and most preferably 3. Preferred branched aliphatic hydrocarbon groups include branched alkylene groups, specifically alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkylalkylene groups such as alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0270] Also, R 101 The cyclic hydrocarbon group in the above may contain heteroatoms, such as heterocycles. Specifically, examples include lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), -SO2--containing cyclic groups represented by the general formulas (b5-r-1) to (b5-r-4), and other heterocyclic groups represented by the chemical formulas (r-hr-1) to (r-hr-16).

[0271] R 101 Examples of substituents on the cyclic group include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, and nitro groups. As the alkyl group used as a substituent, an alkyl group having 1 to 5 carbon atoms is preferred. As the substituent, an alkoxy group having 1 to 5 carbon atoms is preferred, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are more preferred, and a methoxy group and an ethoxy group are most preferred. Preferred halogen atoms as substituents are fluorine, bromine, and iodine atoms. Examples of alkyl halides used as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms are substituted with the halogen atoms. A carbonyl group as a substituent is a group that substitutes for a methylene group (-CH2-) that constitutes a cyclic hydrocarbon group.

[0272] R 101 The cyclic hydrocarbon group in may be a fused ring group containing a fused ring formed by the fusion of an aliphatic hydrocarbon ring and an aromatic ring. Examples of the fused ring include a polycycloalkane having a bridging ring system with one or more aromatic rings fused to it. Specific examples of the bridging ring system polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring group is preferably a group containing a fused ring formed by the fusion of two or three aromatic rings to a bicycloalkane, and more preferably a group containing a fused ring formed by the fusion of two or three aromatic rings to bicyclo[2.2.2]octane. 101 Specific examples of fused ring groups in this context include the groups represented by the following formulas (r-br-1) to (r-br-2). In the formulas, * represents Y in formula (b-1). 101 This represents a coupling that connects to something.

[0273] [ka]

[0274] R 101Examples of substituents that the fused ring group in the compound may have include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, aromatic groups, and alicyclic hydrocarbon groups. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as substituents of the fused cyclic group are as described above in R 101 Examples of substituents on cyclic groups in the above are similar to those listed. Aromatic groups as substituents on the fused ring group include groups obtained by removing one hydrogen atom from an aromatic ring (aryl groups: for example, phenyl groups, naphthyl groups, etc.), groups in which one hydrogen atom of the aromatic ring is replaced by an alkylene group (for example, arylalkyl groups such as benzyl groups, phenethyl groups, 1-naphthylmethyl groups, 2-naphthylmethyl groups, 1-naphthylethyl groups, 2-naphthylethyl groups, etc.), and heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-6). Examples of alicyclic hydrocarbon groups as substituents on the aforementioned fused ring group include groups obtained by removing one hydrogen atom from monocycloalkanes such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 Examples include groups obtained by removing one hydrogen atom from polycycloalkanes such as decane and tetracyclododecane; lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7); -SO2-containing cyclic groups represented by the general formulas (b5-r-1) to (b5-r-4); and heterocyclic groups represented by the formulas (r-hr-7) to (r-hr-16).

[0275] Chain-like alkyl groups that may have substituents: R 101 The chain-like alkyl group may be either linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15, and most preferably 1 to 10. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15, and most preferably 3 to 10. Specifically, examples include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

[0276] A chain-like alkenyl group which may have substituents: R 101 The linear alkenyl group may be linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 2 or 3. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Examples of branched alkenyl groups include 1-methylvinyl groups, 2-methylvinyl groups, 1-methylpropenyl groups, and 2-methylpropenyl groups. Among the above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0277] R 101 Examples of substituents in the chain-like alkyl or alkenyl group include alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, amino groups, and the above R 101 Examples include cyclic groups in this context.

[0278] In formula (b-1), Y 101 It is a single bond or a divalent linking group containing an oxygen atom. Y 101 If Y is a divalent linking group containing an oxygen atom, 101 It may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms, etc. Examples of divalent linking groups containing an oxygen atom include the linking groups represented by the general formulas (L-al-1) to (L-al-8) above. Note that in the general formulas (L-al-1) to (L-al-8) above, R in formula (b-1) 101 The V' in the above general formulas (L-al-1)~(L-al-8) is what combines with it. 101 That is the case.

[0279] In formula (b-1), V 101 These are single bonds, alkylene groups, or fluorinated alkylene groups. Among them, V 101 It is preferable that the fluorinated alkylene group is a single bond or a linear fluorinated alkylene group having 1 to 4 carbon atoms.

[0280] In formula (b-1), R 102 R is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 102 It is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0281] A specific example of the anion part represented by formula (b-1) is, for example, Y 101 When it is a single bond, examples include fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anions and perfluorobutanesulfonate anions; Y 101 When is a divalent linking group containing an oxygen atom, the anions can be represented by any of the following formulas (an-1) to (an-3).

[0282] [ka] [In the formula, R” 101 R” is an optionally substituted aliphatic cyclic group, a monovalent heterocyclic group represented by the above chemical formulas (r-hr-1) to (r-hr-16), a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), an optionally substituted linear alkyl group, or an optionally substituted aromatic cyclic group. 102R” is an aliphatic cyclic group which may have substituents, a fused cyclic group represented by formula (r-br-1) or (r-br-2), a lactone-containing cyclic group represented by the general formulas (a2-r-1), (a2-r-3) to (a2-r-7), respectively, or a -SO2-containing cyclic group represented by the general formulas (b5-r-1) to (b5-r-4), respectively. 103 V” is an optionally substituted aromatic cyclic group, an optionally substituted aliphatic cyclic group, or an optionally substituted linear alkenyl group. 101 This is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. 102 [wherein 'v' is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms; where 'v' is an independent integer from 0 to 3, where 'q' is an independent integer from 0 to 20, and where 'n' is 0 or 1.]

[0283] R" 101 , R” 102 and R” 103 The aliphatic cyclic group which may have substituents is R in formula (b-1) above. 101 It is preferable that the substituent is the group exemplified as a cyclic aliphatic hydrocarbon group in formula (b-1). 101 Examples include substituents similar to those that may be substituted for the cyclic aliphatic hydrocarbon group in the above.

[0284] R" 101 and R” 103 The aromatic cyclic group which may have substituents in formula (b-1) is R 101 It is preferable that the substituent is the group exemplified as an aromatic group in the cyclic hydrocarbon group in the above formula (b-1). 101 Examples include substituents similar to those that may be substituted for the aromatic group in the above.

[0285] R" 101 The chain-like alkyl group which may have substituents in formula (b-1) is R 101 It is preferable that the group is one of the examples given as a chain-like alkyl group in the compound. R"103 The chain-like alkenyl group which may have substituents in formula (b-1) is R 101 It is preferable that the group is one of the examples given as a chain-like alkenyl group in the formula.

[0286] • Anion in component (b-2) In formula (b-2), R 104 , R 105 Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of them is R in formula (b-1). 101 Similar examples can be given. However, R 104 , R 105 These may be bonded to each other to form a ring. R 104 , R 105 The alkyl group is preferably a linear alkyl group which may have substituents, and more preferably a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. The number of carbon atoms in the chain-like alkyl group is preferably 1 to 10, more preferably 1 to 7, and even more preferably 1 to 3. 104 , R 105 The number of carbon atoms in the chain-like alkyl group is preferably small within the above range of carbon atoms, for reasons such as good solubility in the resist solvent. 104 , R 105 In the chain-like alkyl group, a larger number of hydrogen atoms substituted with fluorine atoms is preferable because it increases the acid strength and improves transparency to high-energy light and electron beams below 250 nm. The proportion of fluorine atoms in the chain-like alkyl group, i.e., the fluorination rate, is preferably 70-100%, more preferably 90-100%, and most preferably a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms. In formula (b-2), V 102 , V 103 These are, independently, a single bond, an alkylene group, or a fluorinated alkylene group, and each is V in formula (b-1).101 Similar examples include the above. In formula (b-2), L 101 , L 102 Each of these is either a single bond or an oxygen atom, independently of the others.

[0287] • Anion in component (b-3) In formula (b-3), R 106 ~R 108 Each of these is independently a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of them is R in formula (b-1). 101 Similar examples include the above. In formula (b-3), L 103 ~L 105 These are, independently, single bonds, -CO-, or -SO2-.

[0288] Among the above, the anion portion of component (B) is preferably the anion in component (b-1), and more preferably the anion represented by the formula (an-1).

[0289] {cation part} In the above equations (b-1), (b-2), and (b-3), M' m+ This represents an m-valent onium cation. Among these, sulfonium cations and iodonium cations are preferred. m is an integer of 1 or greater.

[0290] As the cation portion of component (B), a sulfonium cation is preferred, the cations represented by formulas (ca-1) to (ca-3) are more preferred, the cation represented by formula (ca-1) is even more preferred, and the cations represented by formulas (ca-1-1) to (ca-1-104) are particularly preferred. In particular, from the viewpoint of increasing sensitivity and reducing roughness, the cation portion of component (B) is more preferably a cation represented by the above general formula (ca-h-1), and a cation selected from the group consisting of cations represented by the above chemical formulas (ca-1-44) and (ca-1-71) to (ca-1-104), respectively, is particularly preferred.

[0291] In the resist composition of this embodiment, component (B) may be used alone or in combination of two or more types. If the resist composition contains component (B), the content of component (B) in the resist composition is preferably less than 70 parts by mass, more preferably 5 to 60 parts by mass, and even more preferably 10 to 50 parts by mass, per 100 parts by mass of component (A1). (B) It is preferable to set the content of component (B) within the above preferred range, as this makes it easier to obtain a uniform solution when each component of the resist composition is dissolved in an organic solvent, resulting in good storage stability of the resist composition.

[0292] ≪Basic component (D)≫ The resist composition of this embodiment may contain, in addition to component (A), a basic component (component (D)) that traps the acid generated by exposure (i.e., controls the diffusion of the acid). Component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure in the resist composition. Examples of component (D) include a photo-disintegrating base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its ability to control acid diffusion, and a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not fall under component (D1). Among these, a photo-disintegrating base (component (D1)) is preferred because it is easier to improve the characteristics of high sensitivity, roughness reduction, and suppression of coating defects. The components (D1) and (D2) may be in the form of compounds, incorporated into component (A1) as the aforementioned structural unit (a6), or in both forms. The compound exemplified as component (D1) described later may be used as the aforementioned acid-generating component (component (B)) depending on the combination with other compounds.

[0293] • About the (D1) component The (D1) component is not particularly limited as long as it decomposes upon exposure and loses its acid diffusion controllability, and is preferably one or more compounds selected from the group consisting of the compound represented by the following general formula (d1-1) (hereinafter referred to as "(d1-1) component"), the compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component"), and the compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-3) component"). Components (d1-1) to (d1-3) decompose in the exposed areas of the resist film and lose their acid diffusion control properties (basicity), so they do not act as quenchers, but they act as quenchers in the unexposed areas of the resist film.

[0294] [ka] [In the formula, Rd 1 ~Rd 4 Rd in formula (d1-2) is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. 2 In this example, assume that no fluorine atoms are bonded to the carbon atoms adjacent to the sulfur atoms. 1 is a single bond or a divalent linking group. m is an integer greater than or equal to M m+ These are each independently m-valent organic cations.

[0295] {(d1-1) component} ··Anion Club In formula (d1-1), Rd 1 R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and each of the above R' is... 201 Similar examples include the above. Among these, Rd 1Preferred substituents are optionally substituted aromatic hydrocarbon groups, optionally substituted aliphatic cyclic groups, or optionally substituted linear alkyl groups. Examples of substituents these groups may have include hydroxyl groups, oxo groups, alkyl groups, aryl groups, fluorine atoms, fluorinated alkyl groups, lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), ether bonds, ester bonds, or combinations thereof. When ether bonds or ester bonds are included as substituents, they may be mediated via alkylene groups, and in this case, preferred substituents are the linking groups represented by the general formulas (L-al-1) to (L-al-5). Note that Rd 1 If the aromatic hydrocarbon group, aliphatic cyclic group, or linear alkyl group in has a linking group represented by the general formulas (L-al-1) to (L-al-8) as a substituent, then in the general formulas (L-al-1) to (L-al-8), Rd in formula (d1-1) 1 The carbon atom constituting the aromatic hydrocarbon group, aliphatic cyclic group, or linear alkyl group in the above general formula (L-al-1) to (L-al-8) is V'. 101 That is the case. Suitable examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and other ring structures). Examples of the aliphatic cyclic group include adamantane, norbornane, isobornane, and tricyclo[5.2.1.0 2,6 It is more preferable that the group is obtained by removing one or more hydrogen atoms from a polycycloalkane such as decane or tetracyclododecane. The linear alkyl group is preferably one with 1 to 10 carbon atoms, and specifically includes linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups; and branched alkyl groups such as 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, and 4-methylpentyl groups.

[0296] When the chain-like alkyl group is a fluorinated alkyl group having a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and even more preferably 1 to 4. The fluorinated alkyl group may contain atoms other than fluorine. Examples of atoms other than fluorine include oxygen atoms, sulfur atoms, nitrogen atoms, and the like.

[0297] The following are some preferred specific examples of the anionic portion of component (d1-1).

[0298] [ka]

[0299] ··Cation section In formula (d1-1), M m+ This is an m-valent organic cation. M m+ Suitable organic cations include those similar to those represented by the general formulas (ca-1) to (ca-3), with the cation represented by the general formula (ca-1) being more preferred, and the cations represented by the formulas (ca-1-1) to (ca-1-104) being even more preferred. In particular, from the viewpoint of increasing sensitivity and reducing roughness, the cationic portion of component (d1-1) is more preferably a cation represented by the above general formula (ca-h-1), and a cation selected from the group consisting of cations represented by the above chemical formulas (ca-1-44) and (ca-1-71) to (ca-1-104), respectively, is particularly preferred. (d1-1) Component may be used alone or in combination of two or more types.

[0300] {(d1-2) component} ··Anion Club In formula (d1-2), Rd 2 R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. 201 Similar examples include the above. However, Rd 2 In this mixture, we assume that the carbon atom adjacent to the S atom is not bonded to a fluorine atom (i.e., not fluorine-substituted). This results in the anions of components (d1-2) becoming appropriately weak acid anions, improving the quenching ability of component (D). Rd 2 Preferably, the group is a chain-like alkyl group which may have substituents, or an aliphatic cyclic group which may have substituents, and more preferably an aliphatic cyclic group which may have substituents.

[0301] The chain-like alkyl group preferably has 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. Examples of the aliphatic cyclic group include adamantane, norbornane, isobornane, and tricyclo[5.2.1.0 2,6 A group obtained by removing one or more hydrogen atoms from decane, tetracyclododecane, etc. (which may have substituents); more preferably a group obtained by removing one or more hydrogen atoms from camphor.

[0302] Rd 2 The hydrocarbon group may have substituents, and such substituents may be Rd of formula (d1-1). 1Examples include substituents similar to those that may be present on hydrocarbon groups (aromatic hydrocarbon groups, aliphatic cyclic groups, and linear alkyl groups) in the above.

[0303] The following are preferred specific examples of the anionic portion of component (d1-2).

[0304] [ka]

[0305] ··Cation section In formula (d1-2), M m+ is an m-valent organic cation, and M in formula (d1-1) above. m+ It is similar to that. (d1-2) Components may be used individually or in combination of two or more.

[0306] {(d1-3) components} ··Anion Club In formula (d1-3), Rd 3 R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents, and the R' 201 Similar groups are mentioned, and it is preferable that they are cyclic groups containing a fluorine atom, linear alkyl groups, or linear alkenyl groups. Among these, fluorinated alkyl groups are preferred, and the aforementioned Rd 1 A fluorinated alkyl group similar to the one shown is more preferable.

[0307] In formula (d1-3), Rd 4 R' is a cyclic group which may have substituents, a linear alkyl group which may have substituents, or a linear alkenyl group which may have substituents. 201 Similar examples include the above. In particular, alkyl groups, alkoxy groups, alkenyl groups, and cyclic groups, which may have substituents, are preferred. Rd 4The alkyl group in is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. 4 Some of the hydrogen atoms in the alkyl group may be substituted with hydroxyl groups, cyano groups, etc. Rd 4 The alkoxy group in is preferably an alkoxy group having 1 to 5 carbon atoms. Specifically, examples of alkoxy groups having 1 to 5 carbon atoms include the methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, and tert-butoxy group. Among these, the methoxy group and ethoxy group are preferred.

[0308] Rd 4 The alkenyl group in R' 201 Examples of alkenyl groups similar to those in the above include vinyl groups, propenyl groups (allyl groups), 1-methylpropenyl groups, and 2-methylpropenyl groups, which are preferred. These groups may further have substituents of an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

[0309] Rd 4 The cyclic group in is the R' 201 Examples of cyclic groups similar to those in [5.2.1.0] include cyclopentane, cyclohexane, adamantane, norbornane, isobornane, and tricyclo[5.2.1.0]. 2,6 A preferred alicyclic group is obtained by removing one or more hydrogen atoms from a cycloalkane such as decane or tetracyclododecane, or an aromatic group such as a phenyl group or naphthyl group. 4 When Rd is an alicyclic group, the resist composition dissolves well in organic solvents, resulting in good lithography properties. 4 When the group is an aromatic group, the resist composition exhibits excellent light absorption efficiency and good sensitivity and lithographic characteristics in lithography using EUV or the like as the exposure light source.

[0310] In formula (d1-3), Yd1 It is a single bond or a divalent linking group. Yd 1 The divalent linking group in formula (a2-1) is not particularly limited, but may include divalent hydrocarbon groups (aliphatic hydrocarbon groups, aromatic hydrocarbon groups) which may have substituents, and divalent linking groups containing heteroatoms. 21 Examples include divalent hydrocarbon groups that may have substituents, and divalent linking groups containing heteroatoms, as mentioned in the explanation of divalent linking groups in [the relevant section]. Yd 1 The preferred members are carbonyl groups, ester bonds, amide bonds, alkylene groups, or combinations thereof. The alkylene group is more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.

[0311] The following are preferred specific examples of the anionic parts of components (d1-3).

[0312] [ka]

[0313] [ka]

[0314] ··Cation section In formula (d1-3), M m+ is an m-valent organic cation, and M in formula (d1-1) above. m+ It is similar to that. (d1-3) Components may be used individually or in combination of two or more.

[0315] Component (D1) may consist of only one of the above components (d1-1) to (d1-3), or it may consist of a combination of two or more components. If the resist composition contains component (D1), the content of component (D1) in the resist composition is preferably 1 to 30 parts by mass, more preferably 2 to 25 parts by mass, and even more preferably 3 to 20 parts by mass, per 100 parts by mass of component (A1).

[0316] Component (D1) preferably contains the above-mentioned component (d1-1). The content of component (d1-1) in the total amount of component (D1) is preferably 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass or more, and component (D1) may consist only of compound (d1-1).

[0317] In the resist composition of this embodiment, when an onium salt-based acid generator (components (b-1), (b-2), (b-3), etc.) and component (D1) are used in combination as component (B), it is preferable that the cationic portions of both components be cations represented by the general formula (ca-h-1), and particularly preferable that they be cations selected from the group consisting of cations represented by the chemical formulas (ca-1-44) and (ca-1-71) to (ca-1-104), respectively, from the viewpoint of increasing sensitivity and reducing roughness.

[0318] (D1) Method for producing component: The methods for producing the aforementioned components (d1-1) and (d1-2) are not particularly limited and can be produced by known methods. Furthermore, the method for producing components (d1-3) is not particularly limited and may be, for example, similar to the method described in US2012-0149916. As an example of a basic component (component (D)) that traps the acid generated by exposure, a compound of component (D1) is shown, but the compound of component (D1) may also be used as component (B). For example, in the resist composition of this embodiment, the compound of component (D1) may be used as component (B), and the compound that generates an acid with lower acidity than the acid generated by the compound of component (D1) upon exposure may be used as component (D). Alternatively, in the resist composition of this embodiment, the compound of component (D1) may be used as component (B), and the component (D2), which will be described later, may be used as component (D).

[0319] • About the (D2) component Component (D) may include nitrogen-containing organic compounds that do not fall under component (D1) above (hereinafter referred to as "component (D2)"). Component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not fall under component (D1), and any known component may be used. Among these, aliphatic amines are preferred, and among these, secondary aliphatic amines and tertiary aliphatic amines are more preferred. An aliphatic amine is an amine having one or more aliphatic groups, and it is preferable that the aliphatic group has 1 to 12 carbon atoms. Examples of aliphatic amines include amines (alkylamines or alkyl alcoholamines) or cyclic amines in which at least one hydrogen atom of ammonia (NH3) is substituted with an alkyl group or hydroxyalkyl group having 12 or fewer carbon atoms. Specific examples of alkylamines and alkyl alcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkyl alcoholamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 6 to 30 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine are particularly preferred.

[0320] Examples of cyclic amines include heterocyclic compounds containing a nitrogen atom as a heteroatom. These heterocyclic compounds may be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines). Examples of aliphatic monocyclic amines include piperidine and piperazine. As aliphatic polycyclic amines, those having 6 to 10 carbon atoms are preferred, and specifically, examples include 1,5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo[2.2.2]octane.

[0321] Other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxyethoxymethoxy)ethyl}amine, tris{2-(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine, tris{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxyethoxy)ethoxy}ethyl]amine, triethanolamine triacetate, etc., with triethanolamine triacetate being preferred.

[0322] Furthermore, an aromatic amine may be used as component (D2). Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or their derivatives, trimenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, and 2,6-di-tert-butylpyridine.

[0323] (D2) Component may be used alone or in combination of two or more types. When the resist composition contains component (D2), the content of component (D2) in the resist composition is usually in the range of 0.01 to 5 parts by mass per 100 parts by mass of component (A1). By using this range, the resist pattern shape, settling stability over time, etc., are improved.

[0324] <<At least one compound (E) selected from the group consisting of organic carboxylic acids, phosphorus oxoacids and their derivatives>> The resist composition of this embodiment may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives (hereinafter referred to as "component (E)"). Examples of organic carboxylic acids include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid, among which salicylic acid is preferred. Examples of phosphorus oxoacids include phosphoric acid, phosphonic acid, and phosphinic acid, with phosphonic acid being particularly preferred among these.

[0325] In the resist composition of this embodiment, component (E) may be used alone or in combination of two or more types. If the resist composition contains component (E), the content of component (E) is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass, per 100 parts by mass of component (A1). By setting the content within the above range, the lithography characteristics are further improved.

[0326] ≪Fluorine additive component (F)≫ The resist composition of this embodiment may contain a fluorine additive component (hereinafter referred to as "component (F)") as a hydrophobic resin. Component (F) is used to impart water repellency to the resist film and, when used as a resin separate from component (A), can improve lithography properties. As component (F), for example, fluorine-containing polymer compounds described in Japanese Patent Publication No. 2010-002870, Japanese Patent Publication No. 2010-032994, Japanese Patent Publication No. 2010-277043, Japanese Patent Publication No. 2011-13569, and Japanese Patent Publication No. 2011-128226 can be used. More specifically, component (F) includes polymers having a constituent unit (f1) represented by the following general formula (f1-1). This polymer is preferably a polymer (homopolymer) consisting only of the constituent unit (f1) represented by the following formula (f1-1); a copolymer of the constituent unit (f1) and the constituent unit (a1); and more preferably a copolymer of the constituent unit (f1) and a constituent unit derived from acrylic acid or methacrylic acid and the constituent unit (a1). Here, the constituent unit (a1) copolymerized with the constituent unit (f1) is preferably a constituent unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate, and more preferably a constituent unit derived from 1-methyl-1-adamantyl (meth)acrylate.

[0327] [ka] [In the formula, R is the same as above, and Rf 102 and Rf 103 Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf 102 and Rf 103 They may be the same or different. 1 Rf is an integer between 0 and 5. 101 It is an organic group containing a fluorine atom.

[0328] In formula (f1-1), R bonded to the α-carbon atom is the same as described above. R is preferably a hydrogen atom or a methyl group. In formula (f1-1), Rf 102 and Rf 103 A fluorine atom is preferred as the halogen atom. Rf 102 and Rf 103 Examples of alkyl groups having 1 to 5 carbon atoms in R include those similar to the alkyl groups having 1 to 5 carbon atoms in R above, with methyl or ethyl groups being preferred. 102 and Rf103 Specifically, examples of halogenated alkyl groups having 1 to 5 carbon atoms include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Fluorine atoms are preferred as the halogen atoms, particularly Rf. 102 and Rf 103 Preferably, the element is a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms; more preferably, a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group; and even more preferably, a hydrogen atom. In formula (f1-1), nf 1 is an integer between 0 and 5, preferably between 0 and 3, and more preferably 1 or 2.

[0329] In formula (f1-1), Rf 101 This is an organic group containing a fluorine atom, and preferably a hydrocarbon group containing a fluorine atom. The hydrocarbon group containing fluorine atoms may be linear, branched, or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and particularly preferably 1 to 10 carbon atoms. Furthermore, in hydrocarbon groups containing fluorine atoms, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more are fluorinated, and particularly preferable that 60% or more are fluorinated, as this increases the hydrophobicity of the resist film during immersion exposure. Among them, Rf 101 More preferably, fluorinated hydrocarbon groups having 1 to 6 carbon atoms are used, with trifluoromethyl groups, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, and -CH2-CH2-CF2-CF2-CF2-CF3 being particularly preferred.

[0330] The weight-average molecular weight (Mw) of component (F) (based on polystyrene conversion by gel permeation chromatography) is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and most preferably 10,000 to 30,000. If it is below the upper limit of this range, it has sufficient solubility in resist solvents for use as a resist, and if it is above the lower limit of this range, the water repellency of the resist film is good. The degree of dispersion of component (F) (Mw / Mn) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

[0331] In the resist composition of this embodiment, component (F) may be used alone or in combination of two or more types. If the resist composition contains component (F), the content of component (F) is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of component (A1).

[0332] ≪Organic solvent component (S)≫ The resist composition of this embodiment can be manufactured by dissolving the resist material in an organic solvent component (hereinafter referred to as "component (S)"). In the resist composition of this embodiment, component (S) may be used alone or as a mixture of two or more solvents. Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), γ-butyrolactone, ethyl lactate (EL), and cyclohexanone are preferred.

[0333] Furthermore, a mixed solvent obtained by mixing PGMEA and a polar solvent is also preferred as component (S). The mixing ratio (mass ratio) can be appropriately determined considering the compatibility between PGMEA and the polar solvent. As component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferred. In this case, the mass ratio of the former to the latter is preferably 70:30 to 95:5. The amount of component (S) used is not particularly limited and is set appropriately according to the coating thickness, at a concentration that can be applied to a substrate or the like. Generally, component (S) is used so that the solid content concentration of the resist composition is in the range of 0.1 to 20% by mass, preferably 0.2 to 15% by mass.

[0334] The resist composition of this embodiment may further contain, if desired, miscible additives such as additional resins to improve the performance of the resist film, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation agents, dyes, etc.

[0335] The resist composition of this embodiment may be prepared by dissolving the above-mentioned resist material in component (S), and then removing impurities using a polyimide porous membrane, a polyamide-imide porous membrane, or the like. For example, the resist composition may be filtered using a filter made of a polyimide porous membrane, a filter made of a polyamide-imide porous membrane, or a filter made of a polyimide porous membrane and a polyamide-imide porous membrane. Examples of the polyimide porous membrane and the polyamide-imide porous membrane include those described in Japanese Patent Application Publication No. 2016-155121.

[0336] As described above, the resist composition of this embodiment contains a resin component (A1) having a constituent unit (a0) derived from a compound represented by the general formula (a0-m0) as a base component. Compounds represented by such general formula (a0-m0) have acid-dissociable groups (R) that form carbon-carbon bonds other than single bonds. 0 ) has this acid-dissociating group (R 0 ) and polymerizable group-containing group (W 0 ) and a linking group containing an amide structure (-C(=O)-N(R 0 )-L 0 It has -). The acid dissociable group (R 0The group is specifically defined as an aromatic group or an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond that forms a carbon-carbon bond other than a single bond, allowing the acid dissociation reaction to proceed efficiently upon exposure. Therefore, it contributes to improved sensitivity in the formation of resist patterns. The linking group containing the aforementioned amide structure (-C(=O)-N(R 0 )-L 0 The linking group (-C(=O)-N(R)) enhances the glass transition temperature (Tg) of the resin component through the formation of appropriate hydrogen bonds associated with the amide bond. Therefore, in the formation of the resist pattern, the diffusion of acid generated by exposure is suppressed, contributing to reduced pattern roughness and improved exposure margin. In addition, the linking group (-C(=O)-N(R) 0 )-L 0 -) does not contain aromatic rings, and its developability is enhanced. Therefore, it contributes to improved resolution in the formation of resist patterns. Thus, the synergistic effect of the aforementioned effects achieved by employing a specific (A1) component is thought to result in increased sensitivity when forming resist patterns, as well as improved lithography characteristics such as pattern roughness, exposure margin, and resolution, according to the resist composition of this embodiment.

[0337] In a preferred embodiment of the resist composition, the compound represented by the general formula (a0-m0) is L 0 Select a group whose carbon atoms are 1 to 3 aliphatic hydrocarbon groups. In this case, the linking group is partially (-C(=O)-N(R 0 )-) and acid-dissociating group (R 0 The shorter distance from the aromatic ring allows for a higher glass transition temperature (Tg) of the resin component. In addition, the smaller number of carbon atoms compared to the aromatic ring further improves developability and solubility. Therefore, in resist pattern formation, it becomes easier to reduce pattern roughness, improve exposure margins, and enhance resolution.

[0338] (Method for forming resist patterns) A resist pattern formation method according to a second aspect of the present invention is a method comprising the steps of forming a resist film on a support using the resist composition according to the first aspect of the present invention described above, exposing the resist film, and developing the exposed resist film to form a resist pattern. One embodiment of such a resist pattern formation method is, for example, a resist pattern formation method carried out as follows.

[0339] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and a bake (post-application bake (PAB)) treatment is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of, for example, 80 to 150°C, to form a resist film. Next, the resist film is subjected to selective exposure using an exposure apparatus such as an electron beam lithography apparatus or an EUV exposure apparatus, either through exposure via a mask (mask pattern) on which a predetermined pattern has been formed, or by direct irradiation with an electron beam without going through a mask pattern. After this, a bake (post-exposure bake (PEB)) treatment is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of, for example, 80 to 150°C. Next, the resist film is subjected to a developing process. In the case of an alkaline developing process, an alkaline developer is used, and in the case of a solvent developing process, a developer containing an organic solvent (organic developer) is used.

[0340] After the developing process, a rinsing process is preferably performed. In the case of an alkaline developing process, a water rinse using pure water is preferred, and in the case of a solvent developing process, a rinsing solution containing an organic solvent is preferred. In the case of a solvent development process, after the development or rinsing process, a process may be performed to remove the developer or rinse solution adhering to the pattern using a supercritical fluid. After development or rinsing, the film is dried. In some cases, a bake (post-bake) process may be performed after the development process.

[0341] The support material is not particularly limited and can be any conventionally known material, such as a substrate for electronic components or a substrate on which a predetermined wiring pattern has been formed. More specifically, examples include silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, and glass substrates. As for the wiring pattern material, for example, copper, aluminum, nickel, and gold can be used.

[0342] The wavelength used for exposure is not particularly limited, and can be used with radiation such as ArF excimer lasers, KrF excimer lasers, F2 excimer lasers, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, and soft X-rays. The resist pattern formation method of this embodiment is particularly useful in the step of exposing the resist film to EUV (extreme ultraviolet) or EB (electron beam). The method for exposing the resist film may be a normal exposure (dry exposure) performed in an inert gas such as air or nitrogen.

[0343] Examples of alkaline developers used in the alkaline development process include 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution. The organic solvent contained in the organic developer solution used in the solvent development process can be any solvent capable of dissolving component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specifically, examples include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents.

[0344] Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butanoate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate.

[0345] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0346] Organic developers may contain known additives as needed. Examples of such additives include surfactants. While not particularly limited, surfactants such as ionic or nonionic fluorine-based and / or silicon-based surfactants can be used.

[0347] The development process can be carried out by known development methods, such as immersing the support in a developer solution for a certain period of time (dip method), piling the developer solution onto the surface of the support using surface tension and leaving it still for a certain period of time (paddle method), spraying the developer solution onto the surface of the support (spray method), or continuously dispensing the developer solution onto a support rotating at a constant speed while scanning the developer dispensing nozzle at a constant speed (dynamic dispensing method).

[0348] In the solvent-based development process, the rinsing solution used for rinsing after development can contain an organic solvent that is less likely to dissolve the resist pattern, selected from among the organic solvents listed above for use in the organic developer. Typically, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents is used. These organic solvents may be used individually or in combination of two or more. They may also be used in mixtures with other organic solvents or water.

[0349] Rinsing (cleaning) using a rinsing solution can be carried out by known rinsing methods. Examples of such rinsing methods include continuously applying the rinsing solution onto a support rotating at a constant speed (rotary coating method), immersing the support in the rinsing solution for a certain period of time (dip method), and spraying the rinsing solution onto the surface of the support (spray method).

[0350] As described above, the resist pattern formation method of this embodiment uses the above-mentioned resist composition, which allows for increased sensitivity in resist pattern formation, improved lithography characteristics such as pattern roughness and resolution, and the formation of a resist pattern with a wide exposure margin and good shape.

[0351] The resist compositions of the embodiments described above, and the various materials used in the resist pattern formation method of the embodiments described above (for example, resist solvent, developer, rinse solution, anti-reflective film forming composition, top coat forming composition, etc.) are preferably free of impurities such as metals, metal salts containing halogens, acids, alkalis, sulfur atoms, or phosphorus atoms. Examples of impurities containing metal atoms include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The content of impurities in these materials is preferably 200 ppb or less, more preferably 1 ppb or less, even more preferably 100 ppt (parts per trillion) or less, particularly preferably 10 ppt or less, and most preferably substantially free (below the detection limit of the measuring device).

[0352] (Compounds represented by the general formula (a0-m0)) The compound according to the third aspect of the present invention is a compound represented by the following general formula (a0-m0) (compound (M0)).

[0353] [ka] [In the formula, W 0 X represents a polymerizable group-containing group. 0 L represents a hydrogen atom or an alkyl group. 0 R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. 0 represents an acid-dissociating group. However, R 0 In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond.

[0354] The explanation for compounds represented by the general formula (a0-m0) (compound (M0)) is the same as the explanation for compounds represented by the general formula (a0-m0) described in the section on "Constituent Unit (a0)" above. The compound (M0) is L in the general formula (a0-m0). 0 However, it is preferable that the group is an aliphatic hydrocarbon group having 1 to 3 carbon atoms. Alternatively, the compound (M0) may be R in the general formula (a0-m0). 0 However, the above general formula (R 0 A group that is an acid-dissociable group as represented by -1) is preferred. Alternatively, the compound (M0) may be R in the general formula (a0-m0). 0 However, the above general formula (R 0 A group that is an acid-dissociable group as represented in (-2) is preferred.

[0355] The following are preferred specific examples of compound (M0). In each of the following formulas, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0356] [ka]

[0357] [ka]

[0358] [ka]

[0359] [ka]

[0360] [ka]

[0361] [ka]

[0362] [Method for producing compound (M0)] The compound (M0) of this embodiment can be produced by known methods. For example, compound (M0) can be produced by using the raw materials (W) corresponding to the target compound, as described later in [Synthesis of Compound (M0-1)]. 0 Corresponding raw materials, L 0 Corresponding raw materials, R 0 It can be synthesized by selecting the corresponding raw materials and carrying out reactions such as condensation.

[0363] Compound (M0) is, for example, in the presence of a base catalyst, W 0 -C(=O)-N(X 0 )-L 0 -C(=O)-OH and R 0 It can be synthesized by carrying out the reaction (RC) of -OH with a condensing agent in a solvent. W 0 , X 0 , L 0 and R 0 This is W in the above general formula (a0-m0). 0 , X 0 , L 0 and R 0 It is the same as this.

[0364] Examples of base catalysts include tertiary amines such as trimethylamine, triethylamine, and tributylamine; aromatic amines such as pyridine, pyrrolidinopyridine, and 4-(dimethylamino)pyridine (DMAP); and diazabicyclononene (DBN) and diazabicycloundecene (DBU).

[0365] Examples of condensing agents include N,N'-dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide (DIC), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, and carbonyldiimidazole (CDI).

[0366] Examples of solvents include ketone solvents such as cyclohexanone, methyl ethyl ketone, diethyl ketone, and methyl isobutyl ketone; ether solvents such as diethyl ether, t-butyl methyl ether, and diisopropyl ether; halogen solvents such as tetrahydrofuran, 1,3-dioxolane, dichloromethane, 1,2-dichloroethane, and chloroform; ester solvents such as ethyl acetate and propylene glycol monomethyl ether acetate; propionitrile, acetonitrile, or mixtures thereof.

[0367] In the above reaction (RC), the reaction temperature is, for example, 0 to 50°C, and may also be 10 to 30°C, and the reaction time is, for example, 30 minutes to 24 hours, and may also be 1 hour to 20 hours.

[0368] Also, X 0 When is an alkyl group, the compound (M0) is W 0 -C(=O)-NH-L 0 -C(=O)-OH and R 0 It can be synthesized by carrying out the reaction between -OH and in a solvent with the addition of a condensing agent, and then reacting with an alkylating agent in the presence of a base catalyst. Suitable base catalysts in this process include alkali metal hydrides (such as NaH). As for alkylating agents, iodomethane is a suitable choice, for example, as a methylating agent.

[0369] After the above reaction (RC) is completed, the compounds in the reaction solution may be isolated and purified. Conventional methods known can be used for isolation and purification, and for example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography, etc., can be used in appropriate combinations. The structure of the compound obtained as described above can be identified by common organic analysis methods such as ¹H-nuclear magnetic resonance (NMR) spectroscopy, ¹³C-NMR spectroscopy, ¹⁹F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass spectrometry (MS), elemental analysis, and X-ray crystal diffraction. The raw materials and reagents used in the synthesis may be commercially available or synthesized.

[0370] The compound (M0) of this embodiment described above can be used as a raw material monomer for a polymer compound according to the fourth embodiment described later.

[0371] (polymer compound) The polymer compound according to the fourth aspect of the present invention is a polymer compound having a structural unit derived from the compound according to the third aspect described above, and is the same as component (A1) described above.

[0372] The constituent units derived from the compound according to the third embodiment described above are the same as the constituent unit (a0) derived from the compound represented by the general formula (a0-m0) described above. In particular, polymer compounds having such constituent unit (a0) and the constituent unit represented by the general formula (a10-1) described above (constituent unit (a10)) are useful as resist materials for lithography exposed to EUV or EB. The polymer compound according to the fourth embodiment is suitable as a resin for the substrate component of the resist composition according to the first embodiment. [Examples]

[0373] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0374] <Examples of compound synthesis> [Synthesis of compound (M0-1)] A mixed solution of 7.1 g of compound (X-1), 19.3 g of compound (Y-1), 0.6 g of N,N-dimethylaminopyridine (DMAP), and 60 g of dichloromethane was gradually added to a 30 g solution of dichloromethane containing 13.2 g of diisopropylcarbodiimide (DIC). After stirring at room temperature for 18 hours, insoluble matter was removed by filtration, and the mixture was washed with 40 g of water. After removing the solvent by distillation, the target compound (M0-1) was obtained by purification by column chromatography (9.7 g, yield 65%).

[0375] [ka]

[0376] [Synthesis of compounds (M0-2) to (M0-7)] Except for changing compound (Y-1) to compounds (Y-2) through (Y-7), the target compounds (M0-2) through (M0-7) were obtained using the same method as the synthesis of compound (M0-1).

[0377] [ka]

[0378] [ka]

[0379] [Synthesis of compounds (M0-9) to (M0-11)] Except for changing compound (X-1) to compounds (X-2) through (X-4), the target compounds (M0-9) through (M0-11) were obtained using the same method as the synthesis of compound (M0-1).

[0380] [ka]

[0381] [Synthesis of compound (M0-8)] Compound (M0-1) was synthesized, and 9.5 g of this compound (M0-1) was dissolved in 40 g of N,N-dimethylformamide (DMF). To this solution, 1.5 g of sodium hydride (NaH) (60%) and 5.4 g of iodomethane (MeI) were added, and the mixture was stirred at room temperature for 24 hours. Then, 60 g of dichloromethane was added, and the mixture was washed with 40 g of water. After removing the solvent by distillation, the target compound (M0-8) was obtained by purification by column chromatography (7.3 g, yield 73%).

[0382] [ka]

[0383] The compound (M0-1)~compound (M0-11) were obtained, and the NMR measurement was carried out. The following analysis results showed that the structure of the compound (M0-11) was the same.

[0384] Compound (M0-1): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.72(s,-C=CH2,1H),5.40(s,-C=CH2 ,1H),3.80(d,-CH2-,2H),2.43(m,-CH2-,2H),1.84(s,-CH3,3H),1.76(m,-CH2-,2H),1.5-1.7(m,-CH2-,5H),1.29(m,-CH2-,1H)

[0385] Compound (M0-2): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),7.68(d,-Ar,2H),7.13(d,-Ar,2H),5.72( s,-C=CH2,1H),5.40(s,-C=CH2,1H),3.80(d,-CH2-,2H),1.84(s,-CH3,3H),1.70(s,-CH3,6H)

[0386] Compound (M0-3): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),6.22(m,-CH=CH2,1H),5.72(s,-C=CH2,1H),5.40(s,-C=CH2,1H),5.1-5.2( m,-CH=CH2,2H),3.80(d,-CH2-,2H),2.15-2.25(m,-CH2-,2H),1.9-2.0(m,-CH2-,2H),1.84(s,-CH3,3H),1.6-1.8(m,-CH2-,4H)

[0387] Compound (M0-4): 1H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),5.72(s,-C=CH2,1H),5.55(s,-CH=C,1H),5.40(s,-C=CH2,1H),5.1 9(s,-CH-,1H),3.80(d,-CH2-,2H),1.9-2.1(m,-CH2-,2H),1.6-1.9(m,-CH2-,4H),1.84(s,-CH3,3H),1.70(s,-CH3,3H)

[0388] Compound (M0-5): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.72(s,-C=CH2,1H),5.40(s,-C=C H2,1H),3.81(m,-CH2-,2H),3.80(d,-CH2-,2H),3.66(m,-CH2-,2H),2.37(m,-CH2-,2H),2.08(m,-CH2-,2H),1.84(s,-CH3,3H)

[0389] Compound (M0-6): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),7.2-7.4(m,-Ar,5H),5.72(s,-C=CH2 ,1H),5.40(s,-C=CH2,1H),3.80(d,-CH2-,2H),1.8-2.3(m,-CH2-,8H),1.84(s,-CH3,3H)

[0390] Compound (M0-7): 1H-NMR(dmso-d6,400MHz)δ(ppm)=8.28(t,-NH-,1H),7.46(d,Thiophene,1H),7.12(d,Thiophene,1H),6.98(m,Thiophene,1H),5.72(s,-C=CH2,1H),5.40( s,-C=CH2,1H),4.25(d,-CH2-,1H),4.16(d,-CH2-,1H),3.93(m,-CH2-,2H),3 .80(d,-CH2-,2H),2.72(m,-CH2-,1H),2.51(m,-CH2-,1H),1.84(s,-CH3,3H)

[0391] Compound (M0-8): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.66(s,-C=CH2,1H),5.37(s,-C=CH2,1H),3.82(s,-CH2 -,2H),3.08(s,-CH3,3H),2.43(m,-CH2-,2H),1.84(s,-CH3,3H),1.76(m,-CH2-,2H),1.5-1.7(m,-CH2-,5H),1.29(m,-CH2-,1H)

[0392] Compound (M0-9): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.27(d,-NH-,1H),7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.68(s,-C=CH2,1H),5.39(s,-C=CH2,1H),4. 23(m,-CH-,1H),2.43(m,-CH2-,2H),1.84(s,-CH3,3H),1.76(m,-CH2-,2H),1.5-1.7(m,-CH2-,5H),1.29(m,-CH2-,1H),1.25(d,-CH3,3H)

[0393] Compound (M0-10): 1H-NMR(dmso-d6,400MHz)δ(ppm)=8.23(s,-NH-,1H),7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.68(s,-C=CH2,1H),5.39(s,-C=CH2 ,1H),2.43(m,-CH2-,2H),1.84(s,-CH3,3H),1.76(m,-CH2-,2H),1.5-1.7(m,-CH2-,7H),1.29(m,-CH2-,1H),1.24(m,-CH2-,2H)

[0394] Compound (M0-11): 1 H-NMR(dmso-d6,400MHz)δ(ppm)=8.29(t,-NH-,1H),7.3-7.4(m,-Ar,4H),7.25(m,-Ar,1H),5.72(s,-C=CH2,1H),5.40(s,-C=CH2,1H),3.5 6(m,-CH2-,2H),2.55(t,-CH2-,2H),2.43(m,-CH2-,2H),1.84(s,-CH3,3H),1.76(m,-CH2-,2H),1.5-1.7(m,-CH2-,5H),1.29(m,-CH2-,1H)

[0395] <Examples of polymer compound synthesis> [Synthesis of polymer compounds (A1-1)] 12.5 g of compound (M0-1), 4.0 g of compound (a10-1pre), and 1.5 g of azobis(isobutyrate)dimethyl (V-601) as a polymerization initiator were dissolved in 65 g of methyl ethyl ketone (MEK), and the mixture was heated to 80°C under a nitrogen atmosphere and stirred for 8 hours. Then, 1.2 g of trifluoroacetic acid (TFA) and 40 g of t-butanol were added to the reaction mixture, and the mixture was stirred at 30°C for 18 hours. The resulting reaction mixture was added dropwise to 800 g of heptane. The resulting white solid was filtered and dried under reduced pressure for 24 hours to obtain 8.9 g of the target polymer compound (A1-1).

[0396] [ka]

[0397] [Synthesis of polymer compounds (A1-2) to (A1-16)] Polymer compounds (A1-2) to (A1-16) were synthesized using the same method as the synthesis of polymer compound (A1-1), except that the monomer compound used in the polymerization reaction was changed. The monomer compounds used are shown below.

[0398] [ka]

[0399] The synthesized polymer compounds (A1-1) to (A1-16) are shown below. In the following formula, l, m, and n represent the proportion (molar ratio) of each constituent unit in the structural formula.

[0400] [ka]

[0401] [ka]

[0402] [ka]

[0403] [ka]

[0404] [Synthesis of comparative polymer compounds] Except for changing the compound used in the polymerization reaction, polymer compounds (A2-1) to (A2-5) were obtained by the same method as the synthesis of polymer compound (A1-1). The monomer compounds used are listed below.

[0405] [ka]

[0406] The synthesized polymer compounds (A2-1) to (A2-5) are shown below. In the following formula, l and m represent the proportion (molar ratio) of each constituent unit in the structural formula.

[0407] [ka]

[0408] For the obtained polymer compounds (A1-1) to (A1-16) and polymer compounds (A2-1) to (A2-5), the weight-average molecular weight (Mw) and molecular weight dispersion (Mw / Mn) were determined by GPC measurement (converted to standard polystyrene). Furthermore, for polymer compounds (A1-1) to (A1-16) and polymer compounds (A2-1) to (A2-5), the copolymerization composition ratio (the proportion (molar ratio) of each constituent unit in the structural formula) was determined by the carbon-13 nuclear magnetic resonance spectrum (150MHz_ 13 The results were determined by 13C-NMR. The results are shown in Table 1.

[0409] [Table 1]

[0410] <Preparation of the resist composition> (Examples 1-18, Comparative Examples 1-5) Each of the components shown in Tables 2-3 was mixed and dissolved to prepare the resist compositions for each example.

[0411] [Table 2]

[0412] [Table 3]

[0413] In Tables 2 and 3, each abbreviation has the following meaning. The numbers in brackets [ ] represent the amount (parts by mass) of the ingredients. (A1-1)~(A1-16): The above polymer compounds (A1-1)~(A1-16) (A2-1)~(A2-5): The above polymer compound (A2-1)~(A2-5)

[0414] (B-1): An acid generator consisting of a compound represented by the following chemical formula (B-1). (B-2): An acid generator consisting of a compound represented by the following chemical formula (B-2).

[0415] [ka]

[0416] (D-1): An acid diffusion control agent comprising a compound represented by the following chemical formula (D-1). (D-2): An acid diffusion control agent comprising a compound represented by the following chemical formula (D-2).

[0417] [ka]

[0418] (S-1): A mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 20 / 80 (mass ratio).

[0419] <Resist pattern formation> Steps to form a resist film: Each example of the resist composition was applied to an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS) using a spinner, and a 50 nm thick resist film was formed by pre-baking (PAB) on a hot plate at 110°C for 60 seconds and drying.

[0420] The process of exposing the resist film: Next, the resist film was subjected to a JEOL JBX-9300FS electron beam lithography system (manufactured by JEOL Ltd.) at an acceleration voltage of 100kV (Beam current 100pA, Scan step 4nm) to create a 1:1 line-and-space pattern (hereinafter referred to as "LS pattern") with a target size of 35nm line width (70nm pitch width). Subsequently, post-exposure heating (PEB) treatment was performed at 100°C for 60 seconds.

[0421] The process of developing the resist film after exposure: Next, using a developing apparatus (CleanTrack ACT8, manufactured by Tokyo Electron Limited), a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (product name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was dropped onto the resist film from an LD-nozzle at 23°C, and alkaline development was performed for 60 seconds. Afterward, a 15-second rinse was performed using pure water. As a result, in each example, a 1:1 LS pattern with a line width of 35 nm (pitch width of 70 nm) was formed.

[0422] [Sensitivity evaluation] The optimal exposure amount Eop(μC / cm²) for forming the target-sized LS pattern through the aforementioned <resist pattern formation> is used. 2 The result was calculated as "Eop(μC / cm²)". 2 This is shown in Tables 4-5 as follows. A smaller value indicates better sensitivity.

[0423] [Evaluation of pattern roughness] For the LS pattern formed in the <Formation of Resist Pattern> described above, 3σ, a measure of LWR, was determined. The results are shown in Tables 4-5 as "LWR (nm)". "3σ" was determined by measuring the line position at 400 points along the longitudinal direction of the line using a scanning electron microscope (acceleration voltage 800V, product name: S-9380, manufactured by Hitachi High-Technologies Corporation), and calculating three times the standard deviation (σ) (3σ) (unit: nm) from the measurement results. A smaller value of 3σ indicates less roughness on the line sidewalls, resulting in a more uniformly wide LS pattern.

[0424] [Evaluation of exposure margin] The exposure amount required to form a target-size LS pattern, i.e., a 1:1 LS pattern with a space width of 35 nm (pitch width of 70 nm), by the aforementioned <resist pattern formation> was determined to be within ±5% of the target dimensions. The EL margin (%) was then calculated using the following formula. The results are shown in Tables 4-5 as "5%EL (%)".

[0425] EL margin (%) = (|E(+)-E(-)| / Eop) × 100 E(+): Exposure amount (μC / cm²) when a 36.75 nm space width pattern is formed. 2 ) E(-): Exposure amount (μC / cm²) when a 33.25 nm space width pattern is formed. 2 ) A larger EL margin value indicates that the change in pattern dimensions due to variations in exposure is smaller, and that the process margin is wider.

[0426] [Resolution evaluation] In the <Formation of the Resist Pattern> described above, we determined the limiting space width (nm) at which the formed LS pattern could be resolved without bridging when the exposure was reduced from the optimal exposure. The results are shown in Tables 4-5 as the "Bridge Limit (nm)". A smaller value indicates better resolution.

[0427] [Table 4]

[0428] [Table 5]

[0429] The results shown in Tables 4-5, when comparing Examples 1-18 with Comparative Examples 1-5, confirm that using the resist compositions of Examples 1-18 resulted in increased sensitivity and improved pattern roughness, exposure margin, and resolution. On the other hand, when the resist compositions of Comparative Examples 1 to 5 were used, the results were inferior in either sensitivity, pattern roughness, exposure margin, or resolution.

[0430] [Table 6]

[0431] [ka]

[0432] Table 6 summarizes the evaluation results, component (A), and its monomer composition for the resist compositions of Example 1, Comparative Example 1, and Comparative Examples 3-5 described above.

[0433] Comparative Example 5 and Comparative Examples 3 and 4 (W 0 In contrast to the -C(=O)-O- system: Comparative Example 5 Resist Composition (Monomer (m-5), L 0 Compared to the case using a phenylene group, the resist composition of Comparative Example 4 (monomer (m-4), L 0 When using a methylene group, the bridge limit (nm) changes from 28 to 23, and Eop (μC / cm²) decreases. 2 ) improved from 116 to 109. Compared to the case using the resist composition of Comparative Example 4, the resist composition of Comparative Example 3 (monomer (m-3), L 0 = Methylene group, acid-dissociating group (R 0 If a different structure of ) is used, furthermore, Eop(μC / cm2 ) had improved from 109 to 97.

[0434] Comparative Example 5 and Example 1 and Comparative Example 1 (W 0 -Comparison with the C(=O)-NH- system: L 0 When the phenylene group is changed to a methylene group, the resist composition of Comparative Example 5 (monomer (m-5), W 0 Compared to the case using the -C(=O)-O- system, the resist composition of Comparative Example 1 (monomer (m-1), W 0 When using the -C(=O)-NH- system, the bridge limit (nm) changes from 28 to 23, and Eop (μC / cm²) decreases. 2 The EL (luminescence density) improved significantly from 116 to 112, the LWR (nm) improved from 5.7 to 4.7, and the 5% EL (%) improved from 11.7 to 16.1. Compared to the case using the resist composition of Comparative Example 1, the resist composition of Example 1 (monomer (M0-1), W 0 -C(=O)-NH- system, acid dissociable group (R 0 If a different structure of ) is used, furthermore, Eop(μC / cm 2 The EL (Emission Reduction) improved from 112 to 95, the LWR (nm) improved from 4.7 to 3.9, and the 5% EL (%) improved from 16.1 to 16.5.

[0435] From the differences in the changes between Comparative Examples 3 and 4 compared to Comparative Example 5 described above, and the differences in the changes between Example 1 and Comparative Example 1 compared to Comparative Example 5 described above, W 0 In -C(=O)-NH- compounds, the structure of the side chain is a linear or cyclic aliphatic hydrocarbon group (L 0 ) and acid-dissociating group (R 0 The synergistic effect resulting from the combination with W 0 It can be confirmed that this effect is more pronounced compared to the effects of the combination in -C(=O)-O- type compounds.

Claims

1. A resist composition that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, It contains a resin component (A1) whose solubility in the developer changes due to the action of acid, The resin component (A1) is a resist composition having a constituent unit (a0) derived from a compound represented by the following general formula (a0-m0). 【Chemistry 1】 [In the formula, W ０ X represents a polymerizable group-containing group. ０ L represents a hydrogen atom or an alkyl group. ０ R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. ０ represents an acid-dissociating group. However, R ０ In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond.

2. L in the above general formula (a0-m0) ０ The resist composition according to claim 1, wherein the group is an aliphatic hydrocarbon group having 1 to 3 carbon atoms.

3. In the above general formula (a0-m0), R ０ However, the following general formula (R ０ The resist composition according to claim 1 or 2, wherein the acid-dissociable group is represented by -1). 【Chemistry 2】 [In the formula, C* Ｔ represents a tertiary carbon atom. R Ｘ１ is an aromatic group having a carbon-carbon bond other than the single bond formed by the α-position of the tertiary carbon atom (C* Ｔ ) and the β-position of the tertiary carbon atom (C* Ｔ ), or is an aliphatic hydrocarbon group (the aliphatic hydrocarbon group may have a substituent) having a carbon-carbon unsaturated bond formed by the α-position of the tertiary carbon atom (C* Ｔ ) and the β-position of the tertiary carbon atom (C* Ｔ ). R Ｙ１ and R Ｚ１ are each independently a chain saturated hydrocarbon group which may have a substituent, or are bonded to each other to form a saturated aliphatic cyclic group which may have a substituent. *1 represents a bond that bonds to the adjacent oxygen atom (-O-).]

4. In the above general formula (a0-m0), R ０ However, the following general formula (R ０ The resist composition according to claim 1 or 2, wherein the acid-dissociable group is represented by -2). 【Transformation 3】 [In the formula, C* Ｓ This indicates that it is a secondary carbon atom. Ｘ２ is the aforementioned secondary carbon atom (C* Ｓ ) and the α position of the secondary carbon atom (C* Ｓ It is an aromatic group having a carbon-carbon bond other than a single bond formed with the β position of the secondary carbon atom (C* Ｓ ) and the α position of the secondary carbon atom (C* Ｓ R is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed at the β position of ) (the aliphatic hydrocarbon group may have substituents). Ｙ２ R is a chain-like saturated hydrocarbon group which may have substituents, or a saturated aliphatic cyclic group which may have substituents. However, R Ｘ２ and R Ｙ２ This refers to the secondary carbon atoms (C*) that bond to each other. Ｓ ) and the α position of the secondary carbon atom (C* Ｓ A cyclic group having a carbon-carbon bond other than the single bond formed by the β-position of () may be formed (the cyclic group may have substituents). *2 indicates a bond that is attached to an adjacent oxygen atom (-O-).

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

6. A compound represented by the following general formula (a0-m0). 【Chemistry 4】 [In the formula, W ０ X represents a polymerizable group-containing group. ０ L represents a hydrogen atom or an alkyl group. ０ R represents a linear or cyclic aliphatic hydrocarbon group, which may have substituents. ０ represents an acid-dissociating group. However, R ０ In the acid-dissociable group, a carbon atom (C*) is bonded to an adjacent oxygen atom (-O-), and the α-position and β-position of the carbon atom (C*) form a carbon-carbon bond other than a single bond.

7. L in the above general formula (a0-m0) ０ The compound according to claim 6, wherein the compound is an aliphatic hydrocarbon group having 1 to 3 carbon atoms.

8. In the above general formula (a0-m0), R ０ However, the following general formula (R ０ The compound according to claim 6 or 7, wherein the acid-dissociable group is represented by -1). 【Transformation 5】 [In the formula, C* Ｔ This indicates that it is a tertiary carbon atom. Ｘ１ is the aforementioned tertiary carbon atom (C* Ｔ ) and the α position of the tertiary carbon atom (C* Ｔ It is an aromatic group having a carbon-carbon bond other than a single bond formed with the β position of ) or the tertiary carbon atom (C* Ｔ ) and the α position of the tertiary carbon atom (C* Ｔ R is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed at the β position of ) (the aliphatic hydrocarbon group may have substituents). Ｙ１ and R Ｚ１ Each of these is independently a substituted linear saturated hydrocarbon group, or they are bonded to each other to form a substituted saturated aliphatic cyclic group. *1 indicates a bond to an adjacent oxygen atom (-O-).

9. In the above general formula (a0-m0), R ０ However, the following general formula (R ０ The compound according to claim 6 or 7, wherein the acid-dissociable group is represented by -2). 【Transformation 6】 [In the formula, C* Ｓ This indicates that it is a secondary carbon atom. Ｘ２ is the aforementioned secondary carbon atom (C* Ｓ ) and the α position of the secondary carbon atom (C* Ｓ It is an aromatic group having a carbon-carbon bond other than a single bond formed with the β position of the secondary carbon atom (C* Ｓ ) and the α position of the secondary carbon atom (C* Ｓ R is an aliphatic hydrocarbon group having a carbon-carbon unsaturated bond formed at the β position of ) (the aliphatic hydrocarbon group may have substituents). Ｙ２ R is a chain-like saturated hydrocarbon group which may have substituents, or a saturated aliphatic cyclic group which may have substituents. However, R Ｘ２ and R Ｙ２ This refers to the secondary carbon atoms (C*) that bond to each other. Ｓ ) and the α position of the secondary carbon atom (C* Ｓ A cyclic group having a carbon-carbon bond other than the single bond formed by the β-position of () may be formed (the cyclic group may have substituents). *2 indicates a bond that is attached to an adjacent oxygen atom (-O-).

10. A polymer compound having a structural unit derived from the compound described in claim 6 or 7.

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