Resist composition, resist pattern formation method, compound, and polymer compound

Abstract

The present invention provides a resist composition and the like that can form a resist pattern that is highly sensitive, reduces roughness, and improves resolution during the resist pattern formation process. [Solution] A resist composition that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, comprising a resin component (A1) whose solubility in a developer changes due to the action of the acid, wherein the resin component (A1) comprises a constituent unit (a0) derived from a compound represented by the following general formula (a0). In the formula, W 0 X represents a polymerizable group-containing group; 0 represents a hydrogen atom or an alkyl group. TIFF2026111167000106.tif50170

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.

[0003] 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.

[0004] In chemically amplified resist compositions, resins having specific structural units are generally used to improve lithography properties and other characteristics. For example, Patent Document 1 discloses a resist composition containing a resin component (A1) having a constituent unit (a0) that includes a specific acid-dissociable group having a carbon atom constituting a carbon-carbon unsaturated bond. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2019-219469 [Overview of the project] [Problems that the invention aims to solve]

[0006] As lithography technology continues to advance and resist patterns become increasingly miniaturized, for example, EUV (extreme ultraviolet) or EB (electron beam) lithography aims to form fine patterns of tens of nanometers. As pattern dimensions become smaller, high sensitivity to the exposure light source, high resolution, and dimensional uniformity are all required of the lithography characteristics. However, conventional resist compositions, such as those described in Patent Document 1, had room for further improvement in terms of these required characteristics.

[0007] 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 when forming a resist pattern, and that can be made more effective in reducing roughness and improving resolution, a method for forming a resist pattern using the resist composition, a polymer compound useful for the resist composition, and a compound that can be used for the synthesis of the polymer compound. [Means for solving the problem]

[0008] 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) contains a constituent unit (a0) derived from a compound represented by the following general formula (a0).

[0009] [ka] [In the formula, W 0 X represents a polymerizable group-containing group; 0 represents a hydrogen atom or alkyl group; Ar 01 represents an arylene group which may have substituents; La 01 represents a single bond or a divalent linking group; Rpg 0represents an acid dissociable group; n0 represents an integer of 2 or more as long as the valence permits. A plurality of Rpg 0 may be the same or different.]

[0010] A second aspect of the present invention is a resist pattern forming method including a step of forming a resist film on a support using the resist composition according to the first aspect, a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern.

[0011] A third aspect of the present invention is a compound represented by the following general formula (m0).

[0012] [Chemical formula] [In the formula, W 0 represents a polymerizable group-containing group; X 0 represents a hydrogen atom or an alkyl group; Ar 01 represents an arylene group which may have a substituent; La​​​​​​​​​​​​​​​​​​​​​​ In this specification and the claims of this patent, "aliphatic" is a relative concept with respect to aromatic, and is defined to mean a group, compound, etc. that does not have aromaticity. "Alkyl group" shall include linear, branched, and cyclic monovalent saturated hydrocarbon groups unless otherwise specified. The alkyl group in an alkoxy group is the same. "Alkylene group" shall include linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified. "Halogen atom" includes fluorine atom, chlorine atom, bromine atom, iodine atom. "Structural unit" means a monomer unit (monomeric unit) that constitutes a high molecular compound (resin, polymer, copolymer). When it is described as "may have a substituent", it includes both the case of substituting a hydrogen atom (-H) with a monovalent group and the case of substituting a methylene group (-CH2-) with a divalent group. "Exposure" is a concept that includes all irradiations of radiation.

[0016] "Acid-decomposable group" is a group having acid-decomposability in which at least a part of the bonds in the structure of the acid-decomposable group can be cleaved by the action of an acid. Examples of acid-decomposable groups whose polarity increases by the action of an acid include groups that decompose by the action of an acid to generate a polar group. Examples of polar groups include carboxy group, hydroxy group, amino group, sulfo group (-SO3H), etc. More specifically, examples of acid-decomposable groups include groups in which the polar group is protected by an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group). <​​​The acid dissociable group that constitutes the acid decomposable group needs to be a group with lower polarity than the polar group generated by the dissociation of the acid dissociable group. Thus, when the acid dissociable group dissociates due to the action of an acid, a polar group with higher polarity than the acid dissociable group is generated and the polarity increases. As a result, the polarity of the entire component (A1) increases. By increasing the polarity, relatively, the solubility in the developer changes. When the developer is an alkaline developer, the solubility increases, and when the developer is an organic developer, the solubility decreases.

[0018] The "substrate component" is an organic compound having a film-forming ability. The organic compounds used as the substrate component are roughly classified into non-polymers and polymers. As the non-polymer, usually, those having a molecular weight of 500 or more and less than 4000 are used. Hereinafter, when referring to a "low molecular compound", it means a non-polymer having a molecular weight of 500 or more and less than 4000. As the polymer, usually, those having a molecular weight of 1000 or more are used. Hereinafter, when referring to a "resin", "high molecular compound" or "polymer", it means a polymer having a molecular weight of 1000 or more. The molecular weight of the polymer shall be the weight average molecular weight in terms of polystyrene by GPC (gel permeation chromatography).

[0019] The "derived structural unit" means a structural unit formed by the cleavage of a multiple bond between carbon atoms, for example, an ethylenic double bond. The "acrylic ester" may have a hydrogen atom bonded to the α-position carbon atom substituted with a substituent. The substituent (R αx ) that substitutes the hydrogen atom bonded to the α-position carbon atom is an atom or group other than a hydrogen atom. Further, it shall also include a diisopropyl itaconate in which the substituent (R αx ) is substituted with a substituent containing an ester bond, and an α-hydroxyacrylic ester in which the substituent (R αx ) is substituted with a hydroxyalkyl group or a group obtained by modifying its hydroxyl group. The α-position carbon atom of the acrylic ester means, unless otherwise specified, 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.

[0020] 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.

[0021] 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.

[0022] (Resist composition) The resist composition of this embodiment generates acid upon exposure, and its solubility in the 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 the developer changes due to the action of an acid.

[0023] 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), described later, may be used.

[0024] 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. 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.

[0025] 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.

[0026] <Base material component (A)> In the resist composition of this embodiment, it is preferable to use a component (A) that contains 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.

[0027] In the resist composition of this embodiment, component (A) may be used alone or in combination of two or more types.

[0028] (A1) About the ingredients Component (A1) is a resin component whose solubility in the developer changes due to the action of acid.

[0029] ≪Constituent Unit (a0)≫ Component (A1) has a constituent unit (a0) derived from a compound represented by the following general formula (a0) (hereinafter also referred to as "compound (m0)").

[0030] [ka] [In the formula, W 0 X represents a polymerizable group-containing group; 0 represents a hydrogen atom or alkyl group; Ar 01 represents an arylene group which may have substituents; La 01 represents a single bond or a divalent linking group; Rpg 0 n0 represents an acid-dissociable group; n0 represents an integer greater than or equal to 2, as long as the valence allows. Multiple Rpg 0 They may be the same or they may be different.

[0031] In the above formula (a0), W 0 This represents a polymerizable group-containing group. W 0 In the polymerizable group-containing group of "W", the "polymerizable group" is a group that enables a compound having the polymerizable group to polymerize by radical polymerization or the like, and includes, for example, a group containing a multiple bond between carbon atoms such as an ethylenic double bond.

[0032] 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 that may have a substituent, a divalent linking group containing a hetero atom, and the like. Examples of the polymerizable group-containing group include, for example, a group represented by the chemical formula: C(R X11 )(R X12 )=C(R X13 )-Ya x0 - is preferably mentioned. In this chemical formula, R X11 , R X12 and R X13 are each a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, and Ya x0 is a single bond or a divalent linking group. Examples of the divalent linking group in Ya x0 include a divalent hydrocarbon group that may have a substituent, a divalent linking group containing a hetero atom, and the like. Examples of the divalent linking group in Ya x0 include an ester bond (-C(=O)-O-), an oxycarbonyl group (-O-C(=O)-), an amide bond (-C(=O)-NH-, -NH-C(=O)-), an ether bond (-O-), a linear or branched alkylene group, a phenylene group, or a combination thereof. Ya x0 is preferably a single bond or a phenylene group that may have a hydroxy group as a substituent, and from the viewpoint of high sensitivity and reduction of roughness, a phenylene group having a hydroxy group as a substituent is more preferable. When the phenylene group in Ya x0 has a hydroxy group, the number of hydroxy groups is preferably 1 or 2, and more preferably 1.

[0033] In the above formula (a0), X0 represents a hydrogen atom or an alkyl group. X 0 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. X 0 Among the alkyl groups mentioned above, a hydrogen atom, a methyl group, or an ethyl group is preferred, with a hydrogen atom or a methyl group being more preferred.

[0034] In the above formula (a0), Ar 01 This represents an arylene group which may have substituents, and examples of such arylene groups include a phenylene group and a naphthalene diyl group. Ar 01 Of the above, the o-phenylene group, m-phenylene group, or p-phenylene group is preferred, and the p-phenylene group is more preferred. The positional relationship of o-, m-, and p- is as follows: Ar in general formula (a0) 01 N and La 01 This shows the relationship between the substitution positions.

[0035] Ar 01 Examples of substituents that may be present include methyl groups, ethyl groups, propyl groups, alkoxy groups, hydroxyl groups, carboxyl groups, halogen atoms, alkyloxycarbonyl groups, and the like. Ar 01 From the viewpoint of ease of synthesis, it is preferable that the group is an unsubstituted arylene group.

[0036] In the above formula (a0), La 01 This represents a single bond or a divalent linking group. La 01 Examples of divalent linking groups in this context include divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms.

[0037] • Divalent hydrocarbon groups which may have substituents: La 01 The divalent hydrocarbon group in this can be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0038] 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.

[0039] ...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 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. 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.

[0040] The substituents that the linear or branched aliphatic hydrocarbon group may have include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

[0041] ...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 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, tricyclodecane, tetracyclododecane, etc.

[0042] Examples of substituents that a cyclic aliphatic hydrocarbon group may have 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, an ethyl group, a propyl group, an n-butyl group, or a 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-.

[0043] Aromatic hydrocarbon groups The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this carbon number does not include the carbon atoms in substituents. Examples of 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. Examples of aromatic heterocycles include pyridine rings and thiophene rings. Specific examples of aromatic hydrocarbon groups include groups obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); groups obtained by removing two hydrogen atoms from aromatic compounds containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups in which one hydrogen atom of an aryl group or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) is substituted with an alkylene group (e.g., groups obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group 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 bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0044] The aromatic hydrocarbon group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon 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, an ethyl group, a propyl group, an n-butyl group, or a 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.

[0045] • Divalent linking groups containing heteroatoms: La 01 Examples of divalent linking groups containing heteroatoms in this formula 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 have substituents independently, O is an oxygen atom, and m'' is an integer from 0 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 -, -Y21 -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 22 Each 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 between 0 and 3, preferably between 0 and 2, more preferably 0 or 1, and particularly 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’The group represented by "-" is preferred. In the formula, a' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1. b' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1.

[0046] In the formula (a0), La 01 From the viewpoint of ease of synthesis, a single bond is preferred.

[0047] In the formula (a0), Rpg 0 represents an acid dissociable group. Examples of the acid dissociable group include the "acetal-type acid dissociable group", "tertiary alkyl ester-type acid dissociable group", and "secondary alkyl ester-type acid dissociable group" described below.

[0048] Acetal-type acid dissociable group: Rpg 0 Examples of the acid dissociable group in include, for example, an acid dissociable group represented by the following general formula (a0-r-1) (hereinafter sometimes referred to as "acetal-type acid dissociable group").

[0049]

Chemical formula

[0050] In the formula (a0-r-1), Ra 01 and Ra 02 are each independently a hydrogen atom or an alkyl group. In the formula (a0-r-1), Ra 01 and Ra 02Preferably, at least one of them is a hydrogen atom, and more preferably, both are hydrogen atoms. Ra 01 Or Ra 02 If the alkyl group is an alkyl group having 1 to 5 carbon atoms, then an alkyl group having 1 to 5 carbon atoms is preferred. Specifically, linear or branched alkyl groups are preferred. More 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., with methyl or ethyl groups being more preferred, and methyl groups being particularly preferred. In formula (a0-r-1), Ra 01 and Ra 02 Among the above, each is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom or a methyl group.

[0051] In formula (a0-r-1), Ra 03 Examples of hydrocarbon groups include linear or branched alkyl groups, or cyclic hydrocarbon groups. The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specifically, examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. Among these, methyl group, ethyl group, or n-butyl group is preferred, and methyl group or ethyl group is more preferred.

[0052] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., with isopropyl group being preferred.

[0053] Ra 03 When the hydrocarbon group is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. As a monocyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a polycycloalkane from which one hydrogen atom has been removed, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically including adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

[0054] Ra 03 When the cyclic hydrocarbon group becomes an aromatic hydrocarbon group, the aromatic hydrocarbon 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 or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Examples of 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. Examples of aromatic heterocycles include pyridine rings and thiophene rings. Ra 03Specific examples of aromatic hydrocarbon groups in this context include: a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with 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 bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0055] Ra 03 The cyclic hydrocarbon group in may have substituents. Examples of substituents include -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" below) x5 It is also called "[...]." Examples include [...]. Here, R P1 This 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 hydrocarbon group having 6 to 30 carbon atoms. Also, R P2 R is a single bond, a divalent chain 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 hydrocarbon group having 6 to 30 carbon atoms. However, R P1 and R P2Some or all of the hydrogen atoms in the chain-like saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group may be substituted with fluorine atoms. The aliphatic cyclic hydrocarbon group may have one or more of the substituents individually, or it may have one or more of each of the substituents. 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. 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; and polycyclic aliphatic saturated hydrocarbon groups such as bicyclo[2.2.2]octanyl, tricyclo[5.2.1.02,6]decanyl, tricyclo[3.3.1.13,7]decanyl, tetracyclo[6.2.1.13,6.02,7]dodecanyl, and adamantyl groups. Examples of monovalent aromatic hydrocarbon groups having 6 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.

[0056] Ra 03 However, Ra 01 Ra 02 When the cyclic group is bonded to any of the above to form a ring, the cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

[0057] Specific examples of acetal-type acid-dissociating groups are shown below. * indicates a bond.

[0058] [ka]

[0059] Tertiary alkyl ester type acid-dissociating group: RPG 0 Examples of acid-dissociable groups in this context include the acid-dissociable group represented by the following general formula (a0-r-2). Furthermore, among the acid-dissociable groups represented by the following formula (a0-r-2), those composed of alkyl groups may, for convenience, be referred to below as "tertiary alkyl ester type acid-dissociable groups."

[0060] [ka] [In formula (a0-r-2), Ra 04 ~Ra 06 Each of these is independently a hydrocarbon group, and Ra 05 and Ra 06 These elements may join with each other to form a ring. * indicates a bonding hand.

[0061] Ra 04 Examples of hydrocarbon groups include linear or branched alkyl groups, linear or cyclic alkenyl groups, or cyclic hydrocarbon groups. Ra 04 In the above, linear or branched alkyl groups, cyclic hydrocarbon groups (monocyclic aliphatic hydrocarbon groups, polycyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups) are defined as Ra 03 Similar examples include the above. Ra 04 The linear or cyclic alkenyl group in this is preferably an alkenyl group having 2 to 10 carbon atoms. Ra 05 Ra 06 As for the hydrocarbon group, the Ra 03 Similar examples include the above.

[0062] Ra 05 and Ra 06 When these groups bond to each other to form a ring, it is preferable that the group is represented by the following general formula (a0-r2).

[0063] [ka] [In the formula, Ra' 01 It is a hydrocarbon group. 0 Xa is a carbon atom. 0 Ya 0 It is a group that forms an aliphatic cyclic group together with [another group]. Some or all of the hydrogen atoms in this cyclic aliphatic cyclic group may be substituted. * indicates a bond.

[0064] Ra' 01 Examples of hydrocarbon groups include optionally substituted alkyl groups, optionally substituted alkenyl groups, optionally substituted cyclic aliphatic unsaturated hydrocarbon groups, or optionally substituted aromatic cyclic groups.

[0065] Ra' 01 The alkyl group in this may be linear or branched. Ra' 01 The linear alkyl group in this is preferably one with 1 to 10 carbon atoms, more preferably one to 5 carbon atoms, even more preferably one to 4 carbon atoms, and particularly preferably one or two carbon atoms. Specifically, examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. Among these, the methyl group or ethyl group is preferred, and the methyl group is more preferred. Ra' 01 The branched alkyl group in this compound preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and even more preferably 3 to 5 carbon atoms. Specifically, examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, and 2,2-dimethylbutyl group. Among these, isopropyl group or tert-butyl group is preferred, and tert-butyl group is more preferred.

[0066] Ra' 01 The substituents that the alkyl group in the above may have include a halogen atom or the above-mentioned Ra x5 These are some examples.

[0067] Ra' 01The alkenyl group in is preferably an alkenyl group having 2 to 5 carbon atoms. However, this number of carbon atoms does not include the number of carbon atoms in substituents. In the alkenyl group, Ya 0 It is preferable that the carbon atom at the α position and the carbon atom at the β position form a carbon-carbon double bond. The alkenyl group may be linear or branched.

[0068] The linear alkenyl group is preferably an alkenyl group having 2 to 5 carbon atoms. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. The branched alkenyl group is preferably an alkenyl group having 3 to 5 carbon atoms. Examples of branched alkenyl groups include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group.

[0069] Ra' 01 The substituents that the alkenyl group may have include linear saturated hydrocarbon groups and aliphatic cyclic saturated hydrocarbon groups. Examples of the chain-like saturated hydrocarbon group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups. Examples of aliphatic cyclic saturated hydrocarbon groups 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.

[0070] Ra' 01Some or all of the hydrogen atoms of the substituents that the alkenyl group may have are substituted. The substituents are as described above. x5 Similar bases can be cited.

[0071] Ra' 01 Among the alkenyl groups that may have substituents, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0072] Ra' 01 In this context, the cyclic aliphatic unsaturated hydrocarbon group is preferably a cyclic aliphatic unsaturated hydrocarbon group having 5 to 10 carbon atoms. In the aliphatic unsaturated hydrocarbon group, Ya 0 It is preferable that the carbon atom at the α position and the carbon atom at the β position form a carbon-carbon double bond. Examples of the aliphatic unsaturated hydrocarbon group include cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, cyclopentylideneethenyl group, and cyclohexyllideneethenyl group, among which cyclopentenyl group or cyclohexenyl group is preferred, and cyclohexenyl group is more preferred.

[0073] Ra' 01 The substituents that the cyclic aliphatic unsaturated hydrocarbon group in may have are the above-mentioned Ra x5 Similar bases can be cited.

[0074] Ra' 01 Aromatic cyclic groups in this context include aromatic hydrocarbon groups or aromatic heterocyclic groups.

[0075] Ra' 01The aromatic hydrocarbon group in is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms with one or more hydrogen atoms removed; more preferably a group from benzene, naphthalene, anthracene, or phenanthrene with one or more hydrogen atoms removed; even more preferably a group from benzene or naphthalene with one or more hydrogen atoms removed; and particularly preferably a group from benzene with one or more hydrogen atoms removed. Ra' 01 The aromatic heterocyclic group in this is the Ra' 01 Preferably, the aromatic hydrocarbon group in which some of the carbon atoms are substituted with heteroatoms, or a group obtained by removing one or more hydrogen atoms from furan, pyrrole, or thiophene.

[0076] Ra' 01 Examples of substituents that the aromatic cyclic group in the compound may have include methyl, ethyl, propyl, hydroxy, carboxy, halogen atoms, alkoxy groups (such as methoxy, ethoxy, propoxy, and butoxy groups), and alkyloxycarbonyl groups.

[0077] Ra' 01 Among the above, the preferred aromatic cyclic group is a group obtained by removing one or more hydrogen atoms from benzene.

[0078] Xa 0 Ya 0 The aliphatic cyclic group formed together may be either a polycyclic or monocyclic group. As a monocyclic aliphatic cyclic group, a group obtained by removing two or more hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and preferably one having 5 or 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic aliphatic cyclic group is preferably a group obtained by removing two or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms. Specifically, examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0079] Xa 0 Ya 0 Some or all of the hydrogen atoms in the aliphatic cyclic group formed together may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. Specifically, as substituents that replace some or all of the hydrogen atoms of the above aliphatic cyclic group, the above-mentioned Ra x5 Examples include oxygen atoms, sulfur atoms, and nitrogen atoms, when some of the carbon atoms constituting the ring are substituted with heteroatoms.

[0080] Xa 0 Ya 0 Among the above, monocyclic aliphatic cyclic groups are more preferred as the aliphatic cyclic groups formed together, and monocyclic aliphatic cyclic groups having 5 or 6 carbon atoms are even more preferred.

[0081] The groups represented by the above general formula (a0-r2) are preferably those represented by the following general formulas (a0-r2-01) to (a0-r2-03).

[0082] [ka] [In formula (a0-r2-01), Ra 001 This is a linear or branched alkyl group which may have substituents. 0 Xaa is a carbon atom. 0 Yaa 0 It is a group that forms an aliphatic cyclic group together with other groups. Some or all of the hydrogen atoms in this aliphatic cyclic group may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. * indicates a bond. In formula (a0-r2-02), Yab 0 Xab is a carbon atom. 0 Yab 0 It is a group that forms an aliphatic cyclic group together with [another group]. Some or all of the hydrogen atoms in this aliphatic cyclic group may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. 002 ~Ra004 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. 002 ~Ra 004 Two or more of these may be joined together to form a ring structure. * indicates a bonding hand. In formula (a0-r2-03), Yac 0 Xac is a carbon atom. 0 Yac 0 It is a group that forms an aliphatic cyclic group together with [another group]. Some or all of the hydrogen atoms in this aliphatic cyclic group may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. 005 This is an aromatic hydrocarbon group or an aromatic heterocyclic group. Some or all of the hydrogen atoms in this aromatic hydrocarbon group or aromatic heterocyclic group may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. * indicates a bond.

[0083] In formula (a0-r2-01), Ra 001 This is a linear or branched alkyl group, which may have substituents. Ra 001 In this context, the linear or branched alkyl group is the aforementioned Ra' 01 Examples include groups similar to linear or branched alkyl groups in [the relevant context]. Ra 001 The substituents that the alkyl group in the above-mentioned Ra' may have include 01 Examples include substituents similar to those that may be present on the linear or branched alkyl groups in the above.

[0084] In formula (a0-r2-01), Yaa 0 Xaa is a carbon atom, 0 Yaa 0 It is a group that forms an aliphatic cyclic group together with [another group]. The aliphatic cyclic group is Xa in the above formula (a0-r2). 0Ya 0 Examples include aliphatic cyclic groups similar to those formed together.

[0085] Xaa 0 Yaa 0 Some or all of the hydrogen atoms in the aliphatic cyclic group formed together may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. Specifically, as substituents that replace some or all of the hydrogen atoms of the above aliphatic cyclic group, the above-mentioned Ra x5 Examples include oxygen atoms, sulfur atoms, and nitrogen atoms, when some of the carbon atoms constituting the ring are substituted with heteroatoms.

[0086] Xaa 0 Yaa 0 Among the above, monocyclic aliphatic cyclic groups are more preferred as the aliphatic cyclic groups formed together, and monocyclic aliphatic cyclic groups having 5 or 6 carbon atoms are even more preferred.

[0087] In formula (a0-r2-02), Yab 0 Xab is a carbon atom, 0 Yab 0 It is a group that forms an aliphatic cyclic group together with the above formula (a0-r2). This aliphatic cyclic group is Xa in formula (a0-r2). 0 Ya 0 Examples include aliphatic cyclic groups similar to those formed together. Xab 0 Yab 0 Some or all of the hydrogen atoms in the aliphatic cyclic group formed together may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. Specifically, as substituents that replace some or all of the hydrogen atoms of the above aliphatic cyclic group, the above-mentioned Ra x5 Examples include oxygen atoms, sulfur atoms, and nitrogen atoms, when some of the carbon atoms constituting the ring are substituted with heteroatoms.

[0088] Xab 0Yab 0 Among the above, monocyclic aliphatic cyclic groups are more preferred as the aliphatic cyclic groups formed together, and monocyclic aliphatic cyclic groups having 5 or 6 carbon atoms are even more preferred.

[0089] In formula (a0-r2-02), Ra 002 ~Ra 004 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.

[0090] Ra 002 ~Ra 004 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 002 ~Ra 004 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.

[0091] Ra 002 ~Ra 004 In the above, some or all of the hydrogen atoms of the chain-like saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group may be substituted. Specifically, as substituents that substitute some or all of the hydrogen atoms of the chain-like saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group, the above-mentioned Ra x5Examples include oxygen atoms, sulfur atoms, and nitrogen atoms, when some of the carbon atoms constituting the ring are substituted with heteroatoms.

[0092] Ra 002 ~Ra 004 Groups containing a carbon-carbon double bond formed by two or more of these groups bonding to each other to form a cyclic structure include, for example, cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, cyclopentylideneethenyl group, and cyclohexyllideneethenyl group. Among these, cyclopentenyl group, cyclohexenyl group, and cyclopentylideneethenyl group are preferred from the viewpoint of ease of synthesis.

[0093] Ra 002 ~Ra 004 Among the above, hydrogen atoms and monovalent chain saturated hydrocarbon groups having 1 to 10 carbon atoms are preferred, hydrogen atoms, methyl groups, and ethyl groups are more preferred, and hydrogen atoms are even more preferred.

[0094] In formula (a0-r2-03), Yac 0 Xac is a carbon atom, 0 Yac 0 It is a group that forms an aliphatic cyclic group together with the above formula (a0-r2). This aliphatic cyclic group is Xa in formula (a0-r2). 0 Ya 0 Examples include aliphatic cyclic groups similar to those formed together. Xac 0 Yac 0 Some or all of the hydrogen atoms in the aliphatic cyclic group formed together may be substituted, and some of the carbon atoms constituting the ring may be substituted with heteroatoms. Specifically, as substituents that replace some or all of the hydrogen atoms of the above aliphatic cyclic group, the above-mentioned Ra x5 Examples include oxygen atoms, sulfur atoms, and nitrogen atoms, when some of the carbon atoms constituting the ring are substituted with heteroatoms.

[0095] Xac 0 Yac 0 Among the above, monocyclic aliphatic cyclic groups are more preferred as the aliphatic cyclic groups formed together, and monocyclic aliphatic cyclic groups having 5 or 6 carbon atoms are even more preferred.

[0096] In formula (a0-r2-03), Ra 005 This is an aromatic hydrocarbon group or an aromatic heterocyclic group. Ra 005 The aromatic hydrocarbon group in this is Ra' in formula (a0-r2). 01 Examples include similar aromatic hydrocarbon groups in Ra. 005 The aromatic hydrocarbon group in is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms with one or more hydrogen atoms removed; more preferably a group from benzene, naphthalene, anthracene, or phenanthrene with one or more hydrogen atoms removed; even more preferably a group from benzene or naphthalene with one or more hydrogen atoms removed; and particularly preferably a group from benzene with one or more hydrogen atoms removed. Ra 005 The aromatic heterocyclic group in this is Ra' in formula (a0-r2). 01 Examples include similar aromatic heterocyclic groups in Ra. 005 The aromatic heterocyclic group in this is the Ra' 01 Preferably, the aromatic hydrocarbon group in which some of the carbon atoms are substituted with heteroatoms, or a group obtained by removing one or more hydrogen atoms from furan, pyrrole, or thiophene.

[0097] Ra 005 A substituent that may be present is Ra' in formula (a0-r2). 01 Examples include substituents similar to those that may be present on the aromatic cyclic group in the above.

[0098] In the above formula (a0-r-1), Ra 05 and Ra 06 If the groups are independent hydrocarbon groups that are not bonded to each other, it is preferable that they be groups represented by the following general formula (a0-r2-04).

[0099] [ka] [In the formula, Ra 006 and Ra 007 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. 008 This is a hydrocarbon group that may have substituents. * indicates a bond.

[0100] In formula (a0-r2-04), Ra 006 and Ra 007 In this context, the monovalent chain-like saturated hydrocarbon group having 1 to 10 carbon atoms is the aforementioned Ra 002 ~Ra 004 Examples include monovalent chain-like saturated hydrocarbon groups with 1 to 10 carbon atoms. Ra 006 and Ra 007 Among the above, alkyl groups having 1 to 5 carbon atoms are preferred, methyl groups and ethyl groups are more preferred, and methyl groups are even more preferred. Ra 006 and Ra 007 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.

[0101] In formula (a0-r2-04), Ra 008 Ra is a hydrocarbon group which may have substituents. 008 Examples of hydrocarbon groups in this context include linear or branched alkyl groups, linear or branched alkenyl groups, or cyclic hydrocarbon groups. Ra 008 The linear alkyl group in this compound preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and even more preferably 1 or 2. Specifically, examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. Among these, methyl group, ethyl group, or n-butyl group is preferred, and methyl group or ethyl group is more preferred. Ra 008 The branched alkyl group in this compound preferably has 3 to 10 carbon atoms, and more preferably 3 to 5. Specifically, examples include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., with isopropyl group being preferred.

[0102] Ra 008 The linear alkenyl group in this is preferably an alkenyl group having 2 to 5 carbon atoms. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Ra 008 The branched alkenyl group in this is preferably an alkenyl group having 3 to 10 carbon atoms. Examples of branched alkenyl groups include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, and 2-methylpropenyl group. Ra 008 Among the above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0103] Ra 008 When the hydrocarbon group is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a polycycloalkane from which one hydrogen atom has been removed, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically including adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

[0104] Ra 008 As for aromatic hydrocarbon groups in this context, Ra005 Examples include those similar to aromatic hydrocarbon groups in [the text]. Among them, Ra 008 The group is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms with one or more hydrogen atoms removed; more preferably a group from benzene, naphthalene, anthracene, or phenanthrene with one or more hydrogen atoms removed; even more preferably a group from benzene, naphthalene, or anthracene with one or more hydrogen atoms removed; particularly preferably a group from naphthalene or anthracene with one or more hydrogen atoms removed; and most preferably a group from naphthalene with one or more hydrogen atoms removed. Ra 008 A substituent that may be present is Ra 005 Examples of substituents that may be present include those similar to those that Ra has. 008 The substituents that may be present are preferably halogen atoms, and more preferably fluorine atoms.

[0105] Ra in equation (a0-r2-04) 008 If is a naphthyl group, the position where it bonds with the tertiary carbon atom in formula (a1-r2-4) may be either position 1 or position 2 of the naphthyl group. Ra in equation (a0-r2-04) 008 If is an anthyl group, the position where it bonds with the tertiary carbon atom in formula (a0-r2-04) may be position 1, 2, or 9 of the anthyl group.

[0106] In formula (a0-r2-04), Ra 008 Among the above, alkyl groups having 1 to 5 carbon atoms, alkenyl groups having 2 to 5 carbon atoms, and groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms are preferred, with methyl groups, ethyl groups, vinyl groups, and phenyl groups being more preferred.

[0107] Specific examples of the group represented by the above formula (a0-r2-01) are given below.

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] Specific examples of the group represented by the formula (a0-r2-02) are given below.

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] Specific examples of the group represented by the above formula (a0-r2-03) are given below.

[0116] [ka]

[0117] Specific examples of the group represented by the above formula (a0-r2-04) are given below.

[0118] [ka]

[0119] Secondary alkyl ester type acid-dissociating group: RPG 0 Examples of acid-dissociable groups in this context include the acid-dissociable group represented by the following general formula (a0-r-3).

[0120] [ka] [In formula (a0-r-3), Ra 07 Ra is a hydrocarbon group. 08a and Ra 08b Each of these is independently a hydrogen atom, a halogen atom, or an alkyl group. 09 is a hydrogen atom or a hydrocarbon group. 07 and Ra 08a Or Ra 08b These may be joined together to form a ring. 08a Or Ra 08b And, Ra 09 These elements may be joined together to form a ring. * indicates a bonding hand.

[0121] In the formula, Ra 07 and Ra 09 The hydrocarbon group in this is the Ra 01 Similar examples include the above. In the formula, Ra 08a and Ra 08b The alkyl group in is the Ra 01 Examples include alkyl groups similar to those in the above. In the formula, Ra 07 and Ra 09 The hydrocarbon group in, and Ra 08a and Ra 08b The alkyl group in may have substituents. For example, the above-mentioned Ra is an example of such substituent. x5 These are some examples.

[0122] Ra 07 and Ra 08a Or Ra 08b These elements may be bonded to each other to form a ring. This ring may be polycyclic or monocyclic, and may be an alicyclic or aromatic ring. The alicyclic and aromatic rings may also contain heteroatoms.

[0123] Ra 07 and Ra 08a Or Ra08b The rings formed by the bonding of these elements are preferably monocycloalkenes, rings in which some of the carbon atoms of a monocycloalkene are substituted with heteroatoms (oxygen atoms, sulfur atoms, etc.), monocycloalkadienes, cycloalkenes having 3 to 6 carbon atoms, and cyclopentene or cyclohexene.

[0124] Ra 07 and Ra 08a Or Ra 08b The ring formed by the bonding of these elements may be a fused ring. Specific examples of such fused rings include indane.

[0125] Ra 07 and Ra 08a Or Ra 08b The ring formed by the bonding of these elements may have substituents. For example, the above-mentioned Ra x5 These are some examples.

[0126] Ra 08a Or Ra 08b And, Ra 09 These may be bonded together to form a ring, and the ring may be Ra 07 and Ra 08a Or Ra 08b Examples include rings formed by the bonding of these elements together.

[0127] In the above formula (a0-r-3), Ra 07 and Ra 08a Or Ra 08b In this case, among the above, it is preferable that they bond to each other to form a ring, more preferably that they bond to each other to form a monoring, and even more preferably that they bond to each other to form a monoring alicyclic ring. 09 It is preferable that it be a hydrogen atom. Also, Ra 07 and Ra 08a Or Ra 08bThe ring formed by the bonding of these elements may have substituents, preferably alkyl groups having 1 to 5 carbon atoms, more preferably alkyl groups having 1 to 3 carbon atoms, and even more preferably methyl or ethyl groups.

[0128] Ra 07 and Ra 08a Or Ra 08b When these elements combine to form a ring, the above formula (a0-r-3) is preferably the following general formula (a0-r3).

[0129] [ka] [In the formula, Ra 081 and Ra 091 Each is independently either a hydrogen atom or a hydrocarbon group. Y' is a carbon atom. X' is a group that forms a cyclic hydrocarbon group with Y'. Some or all of the hydrogen atoms in this cyclic hydrocarbon group may be substituted. 081 And, Ra 091 These may be joined together to form a ring. * indicates a bonding hand.

[0130] In the formula, Ra 081 and Ra 091 The hydrocarbon group in this is the Ra 01 Similar examples include Ra 081 The hydrocarbon group in is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom or a methyl group. 091 In this case, a hydrogen atom is preferred as the hydrocarbon group.

[0131] Ra 081 And, Ra 091 These may be bonded together to form a ring, and the ring may be the aforementioned Ra 07 and Ra 08a Or Ra 08b Examples include rings formed by the bonding of these elements. 081 And, Ra 091 When these two elements bond to each other to form a ring, Ra081 And, Ra 091 The ring formed by the bonding of these two elements may be a condensed ring in which X' is fused with a cyclic hydrocarbon group formed together with Y'.

[0132] Ra 081 and Ra 091 The hydrocarbon group in may have substituents. For example, the above-mentioned Ra x5 These are some examples.

[0133] In the formula, the cyclic hydrocarbon group that X' forms together with Y' is the aforementioned Ra 07 and Ra 08a Or Ra 08b Examples include rings formed by the bonding of X' and Y'. Among the above, preferred cyclic hydrocarbon groups formed by X' together with Y' are monocycloalkenes, rings in which some of the carbon atoms of a monocycloalken are substituted with heteroatoms (oxygen atoms, sulfur atoms, etc.), monocycloalkadienes, and fused rings, with cycloalkenes having 3 to 6 carbon atoms being preferred, and cyclopentene or cyclohexene being preferred.

[0134] The cyclic hydrocarbon group formed by X' together with Y' may have substituents, preferably alkyl groups having 1 to 5 carbon atoms, more preferably alkyl groups having 1 to 3 carbon atoms, and even more preferably methyl or ethyl groups.

[0135] Specific examples of the group represented by the formula (a0-r-3) are given below.

[0136] [ka]

[0137] In general formula (a0), Rpg 0 In this compound, a tertiary alkyl ester type acid-dissociable group or a secondary alkyl ester type acid-dissociable group is preferred as the acid-dissociable group. From the perspective of improving sensitivity and roughness, RPG 0As the acid-dissociable group in this compound, a cyclic tertiary alkyl ester type acid-dissociable group or a cyclic secondary alkyl ester type acid-dissociable group is more preferred. As a cyclic tertiary alkyl ester type acid-dissociable group, specifically, an acid-dissociable group represented by the above general formula (a0-r2) is preferred, an acid-dissociable group represented by (a0-r2-01), an acid-dissociable group represented by the above general formula (a0-r2-02), or an acid-dissociable group represented by the above general formula (a0-r2-03) is more preferred, and from the viewpoint of increasing sensitivity and / or improving roughness, an acid-dissociable group represented by the above general formula (a0-r2-03) is even more preferred. As a cyclic secondary alkyl ester type acid-dissociable group, specifically, an acid-dissociable group represented by the above general formula (a0-r-3) is preferred, and an acid-dissociable group represented by the above general formula (a0-r3) is more preferred.

[0138] In the general formula (a0), n0 represents an integer of 2 or more, as long as the valence allows. From the viewpoint of ease of synthesis, n0 is preferably 2 to 3, and more preferably 2. Multiple RPGs 0 They may be the same or they may be different. From the viewpoint of ease of synthesis, multiple RPGs 0 It is preferable that they be the same.

[0139] In general formula (a0), La 01 If it is a single bond, Ar 01 The above -C(=O)-O-Rpg 0 The bonding position is not particularly restricted.

[0140] The following are specific examples of the constituent unit (a0). In each of the following formulas, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0141] [ka]

[0142] [ka]

[0143] [ka]

[0144] In the resist composition of this embodiment, the constituent unit (a0) is preferably one of the general formulas (a0-4) to (a0-34), and more preferably one of the formulas (a0-9) to (a0-12), (a0-15) to (a0-18), (a0-21) to (a0-24), or (a0-34).

[0145] 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 30 mol% or more, more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total amount (100 mol%) of all constituent units that make up component (A1). The proportion of constituent units (a0) in component (A1) is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0146] By setting the proportion of constituent units (a0) to above the aforementioned preferred lower limit, the dissolution contrast can be sufficiently increased, making it easier to form a resist pattern with reduced roughness. By keeping the proportion of constituent units (a0) below the aforementioned preferred upper limit, it becomes easier to achieve high sensitivity when forming patterns by balancing them with other constituent units.

[0147] For example, the proportion of constituent unit (a0) in component (A1) is preferably 30 mol% to 90 mol%, more preferably 40 mol% to 80 mol%, and even more preferably 50 mol% to 70 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0148] <<Other constituent units>> Component (A1) may have other constituent units in addition to the constituent unit (a0) described above, as needed. Other constituent units include, for example, constituent units (a1) containing acid-degradable groups whose polarity increases with the action of acid (excluding those corresponding to constituent unit (a0)); constituent units (a10) represented by the general formula (a10-1) described later; constituent units (a2) containing lactone-containing cyclic groups; constituent units (a5) that generate acid upon exposure; and constituent units (a8) derived from compounds represented by the general formula (a8-1) described later.

[0149] Unit of composition (a1): Constituent unit (a1) is a constituent unit that contains an acid-degradable group whose polarity increases upon the action of an acid. However, constituent units corresponding to constituent unit (a0) are excluded from constituent unit (a1).

[0150] As for the constituent unit (a1), Examples of constituent units are those represented by the following general formulas (a1-1), (a1-2), or (a1-3).

[0151] [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. Va 1 n is a divalent hydrocarbon group which may have an ether bond. a1 is an integer between 0 and 2. 1 This is an acid-dissociable group represented by the general formula (a0-r-1), (a0-r-2), or (a0-r-3) above. 1 is n a2 It is a +1 valent hydrocarbon group. a2 is an integer between 1 and 3. 2 This is an acid-dissociable group represented by the above general formula (a0-r-1) or the following general formula (a1-r-3). 001 It is a single bond or a divalent linking group.01 It is a single bond or a divalent linking group. Rax 01 Rz is an acid-dissociable group represented by the general formula (a0-r-1), (a0-r-2), or (a0-r-3) above. 01 [q is an alkyl group, halogen atom, alkyl halide, hydroxyl group, or alkoxy group. q is an integer between 0 and 3. n is a non-negative integer, where n ≤ q × 2 + 4.]

[0152] [ka] [In the formula, Ra' 7 ~Ra' 9 These are each alkyl groups.

[0153] In formula (a1-r-3), Ra' 7 ~Ra' 9 Each of these is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Furthermore, the total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0154] In formulas (a1-1) to (a1-3), the alkyl group of R having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically including methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups. The 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. 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.

[0155] In the above formula (a1-1), Va 1The divalent hydrocarbon group in this expression may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0156] Va 1 The aliphatic hydrocarbon group as a divalent hydrocarbon group in this compound may be saturated or unsaturated, but is usually preferred to be saturated. More specifically, examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, or aliphatic hydrocarbon groups containing a ring in their structure.

[0157] 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.

[0158] Examples of aliphatic hydrocarbon groups containing a ring in the aforementioned structure include alicyclic hydrocarbon groups (groups obtained by removing two hydrogen atoms 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. Examples of the linear or branched aliphatic hydrocarbon group include those similar to the linear or branched aliphatic hydrocarbon group described above. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be polycyclic or monocyclic. 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 2,6Examples include decane and tetracyclododecane.

[0159] Va 1 In this context, an aromatic hydrocarbon group as a divalent hydrocarbon group is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings in aromatic hydrocarbon groups include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, 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. Specific examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); and a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group) in which one hydrogen atom is replaced by an alkylene group (for example, a group obtained by removing one more hydrogen atom from the 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 (alkyl chain in an arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0160] In the above formula (a1-1), Ra 1 The acid-dissociable group is preferably represented by the general formula (a1-r-2) or (a1-r-4) described above, and among these, the group represented by the general formula (a1-r2-1) or the acid-dissociable group represented by the general formula (a1-r-4) is more preferred.

[0161] In the above formula (a1-2), Wa 1 n in a2The +1 valent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity, and may be saturated or unsaturated, but is usually preferred to be saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, or a group that is a combination of a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in its structure. The aforementioned n a2 The +1 valent is preferably 2 to 4 valent, and more preferably 2 or 3 valent. In the above formula (a1-2), Ra 2 The acid-dissociable group represented by the general formula (a1-r-1) above is preferred.

[0162] In the above formula (a1-3), Ya 001 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. Ya 001 The alkylene group is preferably an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched alkylene group, an aromatic hydrocarbon group, or a combination thereof, or a single bond. The alkylene 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. Among these, Ya 001 The combination of an ester bond [-C(=O)-O-, -OC(=O)-] and a linear alkylene group is more preferable, and a single bond is even more preferable.

[0163] In the above formula (a1-3), Ya 01 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. Ya 01Among the above, it is preferable that the ester bond [-C(=O)-O-, -OC(=O)-], ether bond (-O-), linear or branched alkylene group, aromatic hydrocarbon group or a combination thereof, or single bond. Among these, Ya 01 The combination of an ester bond [-C(=O)-O-, -OC(=O)-] and a linear alkylene group is more preferable, and a single bond is even more preferable.

[0164] In the above formula (a1-3), Rax 01 The acid-dissociable group is preferably represented by the general formula (a1-r-2) or (a1-r-4) described above, and among these, the acid-dissociable group represented by the general formula (a1-r-2) is more preferred, and the group represented by the general formula (a1-r2-1) is even more preferred.

[0165] In the above equation (a1-3), Rz 01 The alkyl group, alkyl halide, and alkoxy group in the above preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, even more preferably 1 to 3 carbon atoms, and particularly preferably 1 or 2 carbon atoms. The alkyl group, alkyl halide, and alkoxy group may be linear or branched. Rz 01 In this case, an iodine atom is preferred as the halogen atom. Rz 01 In the alkyl halide, the halogen atom is preferably a fluorine atom, an iodine atom, or a bromine atom, with a fluorine atom being more preferred. Rz 01 The group is preferably an alkoxy group or a hydroxyl group, with a hydroxyl group being more preferred.

[0166] In the above formula (a1-3), q is an integer between 0 and 3. When q is 0, it is a benzene structure; when q is 1, it is a naphthalene structure; when q is 2, it is an anthracene structure; and when q is 3, it is a tetracene structure. In the above formula (a1-3), n is an integer greater than or equal to 0, preferably between 0 and 5, more preferably between 0 and 3, and even more preferably 1 or 2. When n is an integer greater than or equal to 2, Rz is 2 or greater. 01 They may be the same or different from one another. In the above formula (a1-3), n ≤ q × 2 + 4. For example, if q is 1 and the structure is naphthalene, then all six hydrogen atoms in the naphthalene may be substituted with hydroxyl groups. Also, in the naphthalene, Ya 001 、-Ya 01 -C(=O)-O-Ra 01 The substitution positions of the group and the hydroxyl group are not particularly limited.

[0167] 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.

[0168] [ka]

[0169] [ka]

[0170] [ka]

[0171] [ka]

[0172] [ka]

[0173] [ka]

[0174] [ka]

[0175] [ka]

[0176] [ka]

[0177] 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.

[0178] [ka]

[0179] [ka]

[0180] [ka]

[0181] [ka]

[0182] [ka]

[0183] The constituent units (a1) of component (A1) may be one type or two or more types. As for the constituent unit (a1), the constituent unit represented by formula (a1-1) or the constituent unit represented by formula (a1-3) is more preferable because it is easier to improve the characteristics (sensitivity, shape, etc.) in electron beam or EUV lithography.

[0184] The proportion of constituent unit (a1) in component (A1) is preferably 0 to 80 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 CDU improvement are enhanced. 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 across various fields. In this embodiment, component (A1) may or may not have a constituent unit (a1), but it is preferable that it does not have one.

[0185] Unit of composition (a10): The constituent unit (a10) is a constituent unit represented by the following general formula (a10-1).

[0186] [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 hydrocarbon group which may have substituents. ax1 [ is an integer greater than or equal to 1.]

[0187] In formula (a10-1), R is the same as R in general formula (a1-1). 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.

[0188] 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.

[0189] • Divalent hydrocarbon groups which may have substituents: The divalent hydrocarbon group, which may have substituents, may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0190] 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.

[0191] ...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.

[0192] 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.

[0193] ...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.

[0194] 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-.

[0195] Aromatic hydrocarbon groups The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Examples of 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. Examples of aromatic heterocycles include pyridine rings and thiophene rings. Specific examples of aromatic hydrocarbon groups include groups obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); groups obtained by removing two hydrogen atoms from aromatic compounds containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups in which one hydrogen atom of an aryl group or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) is substituted with an alkylene group (e.g., groups obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group 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 bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0196] The aromatic hydrocarbon group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon 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.

[0197] • 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-, -Y21 -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 22 Each 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.

[0198] 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.

[0199] In the above formula (a10-1), Wa x1 This is an aromatic hydrocarbon group which may have substituents. Wa x1 The aromatic hydrocarbon group in this context may be an aromatic ring that 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. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples of the aromatic ring 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. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. Also, Wa x1 The aromatic hydrocarbon group in this context is 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 (nax1 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.

[0200] Wa x1 The aromatic hydrocarbon 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 x1 Examples 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 context, it is preferable that the aromatic hydrocarbon group does not have substituents.

[0201] 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.

[0202] 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.

[0203] [ka]

[0204] [ka]

[0205] [ka]

[0206] 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 10 to 80 mol%, more preferably 20 to 70 mol%, even more preferably 25 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.

[0207] 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.

[0208] 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).

[0209] [ka] [In the formula, Ra' 21 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; 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).

[0210] 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' 21Examples 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.

[0211] 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.

[0212] Ra' 21 Among the above, it is preferable that each is independently a hydrogen atom or a cyano group.

[0213] 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.

[0214] The following are specific examples of groups represented by the general formulas (a²-r-1) to (a²-r-7).

[0215] [ka]

[0216] [ka]

[0217] 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).

[0218] [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. 21 The 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.

[0219] 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.

[0220] 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].

[0221] 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.

[0222] In the above formula (a2-1), Ya 21 It is a single bond, La 21 It is preferable that it be -COO- or -OCO-.

[0223] In the above formula (a2-1), Ra 21 It is a lactone-containing cyclic group. Ra 21Suitable lactone-containing cyclic groups in this compound include those represented by the general formulas (a2-r-1) to (a2-r-7) mentioned above.

[0224] 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 20 mol%, more preferably 1 to 15 mol%, and even more preferably 5 to 15 mol%, relative to the total (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.

[0225] Unit of composition (a5): Component (A1) may have a constituent unit (a5) that generates acid upon exposure, and it is preferable to have the constituent unit (a5) from the viewpoint of improving sensitivity, roughness, and resolution. Known constituent units (a5) can be used. Having the constituent unit (a5) makes it easier for the acid generated upon exposure to be uniformly distributed within the resist film. Examples of constituent units (a5) include constituent units containing the structure described in component (B) below. For example, examples include constituent units containing a structure represented by any of the general formulas (b-1) to (b-3) below. As a constituent unit (a5), for example, a constituent unit represented by the following general formula (a5-1) is preferred.

[0226] [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. 50This 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. 5 This 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.

[0227] {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.

[0228] In the above formula (a5-1), La 50 This is a divalent linking group or a single bond. La 50The 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.

[0229] 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 hydrocarbon group.

[0230] ··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.

[0231] ...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.

[0232] 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.

[0233] ...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.

[0234] 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-.

[0235] ··Ra 50 Aromatic hydrocarbon groups in The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of 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 substituted with heteroatoms. 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. Specific examples of aromatic hydrocarbon groups include groups obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); groups obtained by removing two hydrogen atoms from aromatic compounds containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups in which one hydrogen atom of an aryl group or heteroaryl group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) is substituted with an alkylene group (e.g., groups obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group 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 bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0236] The aromatic hydrocarbon group may have its hydrogen atoms substituted with substituents. For example, the hydrogen atoms bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with substituents. Examples of such substituents include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, and hydroxyl 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. Examples of the substituents include alkoxy groups, halogen atoms, and alkyl halogens that substitute for hydrogen atoms on the cyclic aliphatic hydrocarbon group.

[0237] 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 hydrocarbon groups are preferred.

[0238] 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 hydrocarbon groups which may have substituents, or they may be a combination of alicyclic hydrocarbon groups which may have substituents and aromatic hydrocarbon groups which may have substituents.

[0239] In the above formula (a5-1), La 51 It is a divalent linking group. La 51 Examples 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.

[0240] [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.

[0241] V' 102The 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.

[0242] 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' 102 Specifically, 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 Ra' in formula (a1-r-1). 3 A divalent group is preferred, which is obtained by removing one more hydrogen atom from a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group), and a cyclohexylene group, a 1,5-adamantilene group, or a 2,6-adamantilene group is more preferred.

[0243] La 51Preferably, 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 (L-al-3) or (L-al-8).

[0244] 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.

[0245] 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.

[0246] In the above formula (a5-1), n5 is an integer from 1 to 4, and is preferably 1, 2, or 3.

[0247] {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.

[0248] Preferred cation portion ((M' m+ ) 1 / m Examples of these include organic cations represented by the following general formulas (ca-1) to (ca-3).

[0249] [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-.

[0250] 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. R201 ~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).

[0251] [ka] [In the formula, R' 201 Each 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.

[0252] Cyclic groups that may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferred to be saturated.

[0253] R' 201 The aromatic hydrocarbon group in this context is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in substituents. R' 201Specific examples of aromatic rings in aromatic hydrocarbon groups include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, nitrogen atoms, etc. R' 201 Specific examples of aromatic hydrocarbon 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 the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0254] 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.

[0255] 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.

[0256] 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.

[0257] Also, R' 201 The 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.

[0258] [ka]

[0259] 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.

[0260] 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.

[0261] A chain-like alkenyl group which may have substituents: R' 201The 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 3 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.

[0262] 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.

[0263] R' 201 In addition to those mentioned above, the optionally substituted cyclic groups, optionally substituted linear alkyl groups, or optionally substituted linear alkenyl groups may also include those similar to the acid-dissociable group represented by formula (a1-r-2) above, as optionally substituted cyclic groups or optionally substituted linear alkyl groups.

[0264] 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.

[0265] In the above general formulas (ca-1) to (ca-3), R 201 ~R203 , 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 is preferably a 3 to 10-membered ring, and particularly preferably a 5 to 7-membered ring, 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, a tetrahydrothiopyranium ring, and the like.

[0266] R 208 ~R 209 Each 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.

[0267] 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 210In 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.

[0268] [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.

[0269] In the above general formulas (b5-r-1) to (b5-r-2), B'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, or an oxygen atom or a sulfur atom. For B'', an alkylene group or -O- having 1 to 5 carbon atoms is preferred, an alkylene group having 1 to 5 carbon atoms is more preferred, and a methylene group is even more preferred.

[0270] 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.

[0271] Specific examples of the groups represented by the general formulas (b5-r-1) to (b5-r-4) are given below. In the formulas, "Ac" indicates an acetyl group.

[0272] [ka]

[0273] [ka]

[0274] [ka]

[0275] Specific examples of suitable cations represented by the above formula (ca-1) include the cations represented by the following chemical formulas.

[0276] [ka]

[0277] [ka]

[0278] [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.]

[0279] [ka]

[0280] [ka]

[0281] [ka] [In the formula, R” 201is a hydrogen atom or a substituent, and the substituent is the aforementioned R 201 ~R 207 , and R 210 These are the same substituents that may be present.

[0282] [ka]

[0283] [ka]

[0284] Suitable cations represented by the formula (ca-2) include, specifically, diphenyliodonium cation and bis(4-tert-butylphenyl)iodonium cation.

[0285] 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).

[0286] [ka]

[0287] The cation portion in the above formula (a5-1) ((M' m+ ) 1 / m As for the cation, 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-1-91) are particularly preferred. In particular, from the viewpoint of increasing sensitivity, preferred cations represented by the above formula (ca-1) are those having electron-withdrawing groups such as a fluorine atom, a fluorinated alkyl group, or a sulfonyl group as substituents. For example, cations selected from the group consisting of cations represented by the above chemical formulas (ca-1-44), (ca-1-71) to (ca-1-91) are particularly preferred.

[0288] 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.

[0289] [ka]

[0290] [ka]

[0291] [ka]

[0292] (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 1 to 25 mol%, more preferably 1 to 20 mol%, and even more preferably 5 to 15 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.

[0293] 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.

[0294] 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.

[0295] Unit of composition (a8): The constituent unit (a8) is a constituent unit derived from a compound represented by the following general formula (a8-1). Component (A1) may have the constituent unit (a8).

[0296] [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.]

[0297] W 2 In the polymerizable group-containing group, the "polymerizable group" refers to the polymerizable group W in the constituent unit (a0). 0 Similar examples include the above.

[0298] Ya x2 and W 2 The condensed ring formed by these is W 2 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.

[0299] 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.

[0300] [ka]

[0301] 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).

[0302] 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 0 to 50 mol%, more preferably 0 to 30 mol%, and even more preferably 5 to 15 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0303] The (A1) component contained in the resist composition may be used alone or in combination of two or more types.

[0304] Examples of component (A1) include polymer compounds having a constituent unit (a0); polymer compounds having a constituent unit (a0) and a constituent unit (a10); polymer compounds having a constituent unit (a0), a constituent unit (a10), and a constituent unit (a2); polymer compounds having a constituent unit (a0), a constituent unit (a10), and a constituent unit (a5); polymer compounds having a constituent unit (a0), a constituent unit (a10), and a constituent unit (a8), etc. Component (A1) is preferably a polymer compound consisting of structural unit (a0) and structural unit (a10); a polymer compound consisting of structural unit (a0) and structural unit (a10) and structural unit (a2); a polymer compound consisting of structural unit (a0) and structural unit (a10) and structural unit (a5); or a polymer compound consisting of structural unit (a0) and structural unit (a10) and structural unit (a8).

[0305] In a polymer compound consisting of constituent units (a0) and (a10), the proportion of constituent unit (a0) is more preferably 30 to 90 mol%, even more preferably 40 to 80 mol%, and even 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 10 to 70 mol%, more preferably 20 to 60 mol%, and even more preferably 30 to 50 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0306] In a polymer compound consisting of constituent units (a0), (a10), and (a2), the proportion of constituent unit (a0) is more preferably 30 to 90 mol%, even more preferably 40 to 80 mol%, and even 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 10 to 50 mol%, more preferably 15 to 45 mol%, and even more preferably 20 to 40 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of constituent units (a2) in the polymer compound is preferably 1 to 20 mol%, more preferably 1 to 15 mol%, and even more preferably 5 to 15 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0307] In a polymer compound consisting of constituent units (a0), (a10), and (a5), the proportion of constituent unit (a0) is more preferably 30 to 90 mol%, even more preferably 40 to 80 mol%, and even 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 10 to 50 mol%, more preferably 15 to 45 mol%, and even more preferably 20 to 40 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of constituent units (a5) in the polymer compound is preferably 1 to 25 mol%, more preferably 1 to 20 mol%, and even more preferably 5 to 15 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0308] In a polymer compound consisting of constituent units (a0), (a10), and (a8), the proportion of constituent unit (a0) is more preferably 30 to 90 mol%, even more preferably 40 to 80 mol%, and even 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 10 to 50 mol%, more preferably 15 to 45 mol%, and even more preferably 20 to 40 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound. The proportion of constituent units (a8) in the polymer compound is preferably 1 to 50 mol%, more preferably 1 to 30 mol%, and even more preferably 5 to 15 mol%, relative to the total amount (100 mol%) of all constituent units that make up the polymer compound.

[0309] 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. Examples of monomers that induce each constituent unit include monomers that induce constituent unit (a0) and monomers that induce other constituent units as needed (e.g., constituent units (a10), (a2), (a5), (a8), etc.). These monomers (e.g., monomers that induce constituent unit (a10)) may have their hydroxyl groups or the like protected as needed. In this case, component (A1) can be produced by carrying out a deprotection reaction after the polymerization reaction as described above. 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 in this way are effective in reducing development defects and LER (line edge roughness: uneven unevenness of the line sidewall).

[0310] 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 1,500 to 40,000, and even more preferably 2,000 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.

[0311] (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.

[0312] 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 also be 100% by mass, based on the total mass of component (A). When the proportion is 25% by mass or more, sensitivity tends to improve, and a resist pattern with excellent lithography characteristics such as resolution and roughness is more easily formed.

[0313] In the resist composition of this embodiment, the content of component (A) may be adjusted according to the resist film thickness to be formed.

[0314] <Acid generating agent component (B)> The resist composition of this embodiment may 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.

[0315] 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)").

[0316] [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 102 Each of these is independently either a single bond or an oxygen atom. 103 ~L 105These 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.

[0317] {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.

[0318] Cyclic groups that may have substituents: The cyclic group is preferably a cyclic hydrocarbon group, which may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group is preferably saturated.

[0319] R 101 The aromatic hydrocarbon group in this formula is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in substituents. R 101 Specific examples of aromatic rings in aromatic hydrocarbon groups include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, nitrogen atoms, etc. R 101Specific examples of aromatic hydrocarbon 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.

[0320] 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.

[0321] Among them, R 101The 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.

[0322] 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.

[0323] Also, R 101The 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).

[0324] 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.

[0325] R 101The 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.

[0326] [ka]

[0327] R 101 Examples 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 hydrocarbon 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 include those similar to those listed in [reference]. Examples of aromatic hydrocarbon 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 of the hydrogen atoms 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).

[0328] 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.

[0329] 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 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.

[0330] 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.

[0331] 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) below, R in formula (b-1) above 101 The combination with this is V' in the following general formulas (L-al-1)~(L-al-8). 101 That is the case.

[0332] 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 chain having 1 to 4 carbon atoms.

[0333] 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.

[0334] A specific example of the anion part represented by the above 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).

[0335] [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. 102 R” 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.]

[0336] R" 101 , R” 102 and R” 103 The aliphatic cyclic group which may have substituents is R in formula (b-1) above. 101It 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.

[0337] 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 aromatic hydrocarbon group exemplified in the cyclic hydrocarbon group in formula (b-1). 101 Examples include substituents similar to those that may be substituted for the aromatic hydrocarbon group in the above.

[0338] 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.

[0339] • 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 higher 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.

[0340] • 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-.

[0341] 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).

[0342] {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.

[0343] 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-1-91) are particularly preferred.

[0344] 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 5 to 70 parts by mass, more preferably 10 to 60 parts by mass, and even more preferably 15 to 50 parts by mass, per 100 parts by mass of component (A). (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.

[0345] <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.

[0346] • 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.

[0347] [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 Mm+ These are each independently m-valent organic cations.

[0348] {(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 1 Preferred 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 2,6It 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.

[0349] 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.

[0350] The following are some preferred specific examples of the anionic portion of component (d1-1).

[0351] [ka]

[0352] ··Cation section In formula (d1-1), M m+ This is an m-valent organic cation. M m+ Suitable organic cations include those similar to the cations represented by the general formulas (ca-1) to (ca-3), respectively, 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-1-84) being even more preferred. (d1-1) Component may be used alone or in combination of two or more types.

[0353] {(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.

[0354] 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.

[0355] Rd 2 The hydrocarbon group may have substituents, and such substituents may be Rd of formula (d1-1). 1 Examples 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.

[0356] The following are preferred specific examples of the anionic portion of component (d1-2).

[0357] [ka]

[0358] ··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.

[0359] {(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 to the above, it is preferable that the group is a cyclic group containing a fluorine atom, a linear alkyl group, or a linear alkenyl group. Among these, a fluorinated alkyl group is preferred, and the above Rd 1 A fluorinated alkyl group similar to the one shown is more preferable.

[0360] 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 4 The 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 4The 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.

[0361] 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.

[0362] Rd 4 The cyclic group in is 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.

[0363] In formula (d1-3), Yd 1 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. 21Examples include divalent hydrocarbon groups that may have substituents, and divalent linking groups containing heteroatoms, as mentioned in the explanation of divalent linking groups in [reference]. 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.

[0364] The following are preferred specific examples of the anionic parts of components (d1-3).

[0365] [ka]

[0366] [ka]

[0367] ··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.

[0368] 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 0.5 to 50 parts by mass, more preferably 1 to 40 parts by mass, and even more preferably 2 to 20 parts by mass, per 100 parts by mass of component (A).

[0369] 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).

[0370] (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).

[0371] • 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.

[0372] 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.

[0373] 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.

[0374] 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.

[0375] (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 (A). By using this range, the resist pattern shape, aging stability, etc., are improved.

[0376] <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.

[0377] 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 (A). By setting the content within the above range, the lithography characteristics are further improved.

[0378] <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.

[0379] [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.

[0380] 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.

[0381] 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.

[0382] 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.

[0383] 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 (A).

[0384] <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.

[0385] 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.

[0386] The resist composition of this embodiment may be subjected to removal of impurities after dissolving the resist material in component (S), 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.

[0387] The resist composition of this embodiment described above contains a resin component (A1) having a constituent unit (a0) derived from a compound represented by the general formula (a0). The constituent unit (a0) has an acid-degradable group -C(=O)-O-Rpg as a substituent on the arylene group. 0 Because it has two or more of these groups, the solubility of the exposed areas of the resist film in the developer is improved during resist pattern formation. Furthermore, the constituent unit (a0) has an amide bond between the arylene group and the polymerizable group. Since the amide bond is hydrophilic, the solubility of the exposed areas of the resist film in the developer is improved during resist pattern formation. It is presumed that the improved solubility of the exposed areas of the resist film in the developer leads to increased sensitivity and improved resolution. Generally, as the number of acid-degradable groups in the substrate components increases, acid tends to diffuse more easily during exposure. However, amide bonds have a moderate proton affinity. Therefore, when forming a resist pattern, the constituent unit (a0) is the acid-degradable group -C(=O)-O-Rpg 0 Despite having two or more amide bonds, it is presumed that acid diffusion is controlled by the amide bond, improving the dissolution contrast between the exposed and unexposed areas and thus improving roughness. Therefore, it is presumed that the resist composition of this embodiment works synergistically, resulting in increased sensitivity, reduced roughness, and improved resolution when forming a resist pattern.

[0388] (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.

[0389] 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 ArF 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.

[0390] 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.

[0391] 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.

[0392] 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).

[0393] The method for exposing the resist film may be conventional exposure (dry exposure) performed in an inert gas such as air or nitrogen, or it may be liquid immersion lithography. Immersion lithography is an exposure method in which the space between the resist film and the lens at the lowest position of the exposure apparatus is first filled with a solvent (immersion medium) that has a refractive index greater than that of air, and then exposure (immersion exposure) is performed in that state. As the immersion medium, a solvent having a refractive index greater than that of air and less than that of the resist film being exposed is preferred. Examples include water, fluorinated inert liquids, silicon-based solvents, and hydrocarbon-based solvents. Water is preferably used as the immersion medium.

[0394] 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.

[0395] 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.

[0396] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0397] 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.

[0398] 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).

[0399] 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.

[0400] 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).

[0401] As described above, the resist pattern formation method of this embodiment uses the above-mentioned resist composition, so it is presumed that high sensitivity can be achieved, roughness can be reduced, and a resist pattern can be formed with high resolution.

[0402] The resist compositions of the embodiments described above, and the various materials used in the pattern forming methods of the embodiments described above (for example, resist solvents, developers, rinse solutions, anti-reflective film forming compositions, topcoat forming compositions, etc.) are preferably free from impurities such as metals, metal salts containing halogens, acids, alkalis, sulfur atoms, or phosphorus atoms. Examples of metal atom-containing impurities include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The impurity content 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).

[0403] (compound) The compound according to the third aspect of the present invention is a compound represented by the following general formula (m0) (hereinafter also referred to as "compound (m0)").

[0404] [ka] [In the formula, W 0 X represents a polymerizable group-containing group; 0 represents a hydrogen atom or alkyl group; Ar 01 represents an arylene group which may have substituents; La 01 represents a single bond or a divalent linking group; Rpg 0 n0 represents an acid-dissociable group; n0 represents an integer greater than or equal to 2, as long as the valence allows. Multiple Rpg 0 They may be the same or they may be different.

[0405] In the general formula (m0), W 0 , X 0 Ar 01 , L 01 , and RPG 0 This is W in the above general formula (a0). 0 , X 0 Ar 01 , L01 , and RPG 0 These are the same.

[0406] Specific examples of compound (m0) are given below, but are not limited to these. In each of the following formulas, Rβ represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0407] [ka]

[0408] [ka]

[0409] [ka]

[0410] <Method for producing compounds> Compound (m0) can be produced by appropriately combining known methods, as shown in the <Synthesis Example of Compound> in the [Examples] section below.

[0411] The compounds of this embodiment described above can be used in the production of the resist composition according to the first embodiment. Furthermore, the compounds of this embodiment can be used in the production of the polymer compound according to the fourth embodiment, which will be described later.

[0412] (polymer compound) A polymer compound according to a fourth aspect of the present invention has a constituent unit (a0) derived from the compound (m0). The constituent unit (a0) is the same as described above. The polymer compound of this embodiment can be used in the manufacture of the resist composition according to the first embodiment described above. By incorporating the polymer compound of this embodiment into the resist composition, sensitivity can be increased during resist pattern formation, and the effect of reducing roughness and improving resolution can be enhanced. [Examples]

[0413] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0414] <Examples of compound synthesis> (Example of compound (m0-1) synthesis) 6.9 g of compound (m0-1a) was dissolved in 40 g of dimethylformamide (DMF), and 14.3 g of carbonyldiimidazole (CDI) was added to the solution. After stirring at room temperature for 30 minutes, a solution of 5.7 g of compound (m0-1b) and 2.5 g of diazabicycloundecene (DBU) in 20 g of DMF was added. After stirring at 30°C for 20 hours, 80 g of dichloromethane was added and the mixture was washed with 80 g of water. After removing the solvent by distillation, compound (m0-1) was obtained by purification by column chromatography (6.8 g, yield 68%).

[0415] [ka]

[0416] The obtained compound (m0-1) was subjected to NMR measurement, and its structure was identified based on the analytical results shown below. 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar, 1H),5.90(s,-C=CH2,1H),5.58(s,-C=CH2,1H),1.98(s,-CH3,3H),1.49(s,-CH3,18H)

[0417] (Synthesis of compounds (m0-2) to (m0-6)) Compounds (m0-2) to (m0-6) were synthesized in the same manner as compound (m0-1), except that compounds (m0-2b) to (m0-6b) were used instead of compound (m0-1b).

[0418] [ka]

[0419] The obtained compounds (m0-2) to (m0-6) are shown below.

[0420] [ka]

[0421] (Synthesis of compounds (m0-7), (m0-9), and (m0-10)) Compounds (m0-7), (m0-9), and (m0-10) were synthesized in the same manner as compound (m0-1), except that compounds (m0-2a) to (m0-4a) were used instead of compound (m0-1a), and compound (m0-2b) was used instead of compound (m0-1b).

[0422] [ka]

[0423] The obtained compounds (m0-2) to (m0-6) are shown below.

[0424] [ka]

[0425] (Synthesis of compound m0-8) 5.8 g of compound (m0-2) was dissolved in 40 g of DMF, and 0.8 g of sodium hydride (60%) and 2.8 g of iodomethane were added to the solution. After stirring at room temperature for 24 hours, 60 g of dichloromethane was added, and the mixture was washed with 40 g of water. After removing the solvent by distillation, compound (m0-8) was obtained by purification by column chromatography (3.6 g, yield 60%).

[0426] [ka]

[0427] The compounds (m0-2)~(m0-10) were obtained, and the NMR measurement was carried out. The following analysis results showed that the structure of the compound was the same as that of the compound.

[0428] Compound (m0-2): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),5.90(s,-C=CH2, 1H),5.58(s,-C=CH2,1H),2.2(m,-CH2-,4H),1.98(s,-CH3,3H),1.6-1.8(m,-CH2-,12H),1.62(s,-CH3,6H)

[0429] Compound (m0-3): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),6.22(m,-CH=CH2,2H),5.90(s,-C=CH2,1H),5. 58(s,-C=CH2,1H),5.1-5.2(m,-CH=CH2,4H),2.15-2.25(m,-CH2-,4H),1.9-2.0(m,-CH2-,4H),1.98(s,-CH3,3H),1.6-1.8(m,-CH2-,8H)

[0430] Compound (m0-4): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),7.2-7.3(m,-Ar,5H),5.90(s,-C=CH2,1 H),5.58(s,-C=CH2,1H),2.4(m,-CH2-,4H),1.98(s,-CH3,3H),1.7-1.8(m,-CH2-,4H),1.5-1.7(m,-CH2-,10H),1.3(m,-CH2-,2H)

[0431] Compound (m0-5): 1H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),7.2-7.4(m,-Ar,5H),5.90(s,-C=CH2,1H),5. 58(s,-C=CH2,1H),3.82(m,-CH2-,4H),3.66(m,-CH2-,4H),2.38(m,-CH2-,4H),2.08(m,-CH2-,4H),1.98(s,-CH3,3H),1.95(s,-CH3,6H)

[0432] Compound (m0-6): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),5.90(s,-C=CH2,1H),5.58 (s,-C=CH2,2H),5.46(s,-CH-,2H),5.18(s,-CH-,1H),1.5-2.0(m,-CH2-,12H),1.98(s,-CH3,3H),1.70(s,-CH3,6H)

[0433] Compound (m0-7): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),7.92(d,-Ar,1H),7.8-7.9(m,-Ar,2H),5.90(s,-C=CH 2,1H),5.58(s,-C=CH2,1H),2.2(m,-CH2-,4H),1.98(s,-CH3,3H),1.6-1.8(m,-CH2-,12H),1.62(s,-CH3,6H)

[0434] Compound (m0-8): 1H-NMR (DMSO-d6, 400MHz): δ(ppm)=8.48(d,-Ar,2H),8.10(d,-Ar,1H),5.90(s,-C=CH2,1H),5.58(s,-C=CH 2,1H),3.10(s,-NH-,1H),2.2(m,-CH2-,4H),1.98(s,-CH3,3H),1.6-1.8(m,-CH2-,12H),1.62(s,-CH3,6H)

[0435] Compound (m0-9): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),7.92(d,-Ar,2H),7.58(d,-Ar,2H),6. 82(dd,-CH=CH2,1H),5.98(d,-CH=CH2,1H),5.38(d,-CH=CH2,1H),2.2(m,-CH2-,4H),1.6-1.8(m,-CH2-,12H),1.62(s,-CH3,6H)

[0436] Compound (m0-10): 1 H-NMR (DMSO-d6, 400MHz): δ(ppm)=10.78(s,-OH,1H),10.18(s,-NH-,1H),8.56(d,-Ar,2H),8.10(d,-Ar,1H),7.7-7.8(m,-Ar,1H),6.96(d, -Ar,1H),6.70(dd,-CH=CH2,1H),5.70(d,-CH=CH2,1H),5.16(d,-CH=CH2,1H),2.2(m,-CH2-,4H),1.6-1.8(m,-CH2-,12H),1.62(s,-CH3,6H)

[0437] <Manufacture of polymer compounds> (Synthesis of polymer compound (A1-1)) 9.4 g of compound (m0-1), 2.5 g of compound (m10-1-pre), and 0.7 g of azobis(isobutyrate)dimethyl (V-601) as a polymerization initiator were dissolved in 35 g of MEK (methyl ethyl ketone), and the mixture was heated to 80°C under a nitrogen atmosphere and stirred for 6 hours. Then, 0.8 g of trifluoroacetic acid and 50 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 600 g of heptane. The resulting white solid was filtered and dried under reduced pressure overnight to obtain 6.0 g of the target polymer compound (A1-1).

[0438] [ka]

[0439] (Synthesis of polymer compounds (A1-2) to (A1-15)) Polymer compounds (A1-2) to (A1-15) were synthesized in the same manner as polymer compound (A1-1), except that the compound used in the polymerization reaction was changed.

[0440] The obtained polymer compounds (A1-1) to (A1-15) are shown below. In the following formulas, l, m, and n represent the composition ratio (molar ratio) of each constituent unit.

[0441] [ka]

[0442] [ka]

[0443] [ka]

[0444] (Synthesis of comparative polymer compounds) Polymer compounds (A2-1) to (A2-6) were obtained using the same method as the synthesis of polymer compound (A1-1), except that the compounds used in the polymerization reaction were changed. The obtained polymer compounds (A2-1) to (A2-6) are shown below. In the following formulas, l and m represent the composition ratio (molar ratio) of each constituent unit.

[0445] [ka]

[0446] For the obtained polymer compounds (A1-1) to (A1-15) and polymer compounds (A2-1) to (A2-6), the weight-average molecular weight (Mw) and molecular weight dispersion (Mw / Mn) were determined by GPC measurement (standard polystyrene equivalent). Furthermore, for polymer compounds (A1-1) to (A1-15) and polymer compounds (A2-1) to (A2-6), the copolymerization composition ratio (proportion of each constituent unit in the structural formula (molar ratio)) was determined by carbon-13 nuclear magnetic resonance spectroscopy (600 MHz, 13 The results were determined by 13C-NMR. The results are shown in Table 1.

[0447] [Table 1]

[0448] <Preparation of the resist composition> (Examples 1-17, Comparative Examples 1-6) Each example of a resist composition was prepared by mixing and dissolving the components shown in Tables 2 and 3.

[0449] [Table 2]

[0450] [Table 3]

[0451] 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 to (A1)-15: The above polymer compounds (A1-1) to (A1-16). (A2)-1 to (A2)-5: the above-mentioned polymer compounds (A2-1) to (A2-5). (B)-1~(B)-2: Acid generators consisting of the following compounds (B-1)~(B-2).

[0452] [ka]

[0453] (D)-1~(D)-2: Acid diffusion control agents consisting of compounds represented by the following chemical formulas (D-1)~(D-2).

[0454] [ka]

[0455] (S)-1: A mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 20 / 80 (mass ratio).

[0456] <Resist pattern formation> Steps to form a resist film: Each example of the resist composition was applied to a silicon substrate treated with hexamethyldisilazane (HMDS) using a spinner, and a 60 nm thick resist film was formed by pre-baking (PAB) on a hot plate at 110°C for 60 seconds and drying.

[0457] 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, and a 1:1 line-and-space pattern (hereinafter referred to as "LS pattern") with a target size of 35nm line width was created. Subsequently, post-exposure heating (PEB) treatment was performed at 100°C for 60 seconds.

[0458] The process of developing the resist film after exposure: Next, alkaline development was performed at 23°C for 60 seconds using a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (product name, manufactured by Tokyo Ohka Kogyo Co., Ltd.). After that, a water rinse was performed with pure water for 15 seconds. As a result, a contact hole pattern (CH pattern) with a hole diameter of 26 nm and a pitch of 46 nm was formed.

[0459] [Evaluation of optimal exposure (Eop)] The optimal exposure amount Eop(μC / cm²) for forming a CH pattern of the target size through the above <resist pattern formation> method is to form a CH pattern of the target size. 2 We calculated this as "Eop(μC / cm²)". 2 )" is shown in Table 4.

[0460] [Evaluation of in-plane uniformity (CDU) of pattern dimensions] For the CH pattern formed by the "resist pattern formation" described above, 3σ, a measure of CDU, was determined. The hole diameter (nm) of each hole was measured by observing the CH pattern from above using a length-measuring SEM (scanning electron microscope, acceleration voltage 500V, product name: CG5000, Hitachi High-Technologies Corporation). Then, three times the standard deviation (σ) calculated from the measurement results (3σ) was determined. The results are shown in Table 4 as "CDU (nm)". A smaller value of 3σ indicates higher uniformity of the dimensions (CD) of the multiple holes formed in the resist film, meaning that the pattern roughness (CDU) is superior.

[0461] [Evaluation of the finest limit resolution] In the evaluation conditions for "resist pattern formation" described above, the limit of the resolvable pattern size as the exposure amount was reduced was used as the evaluation of fine resolution. The results are shown in Table 4 as "limiting resolution (nm)".

[0462] [Table 4]

[0463] As shown in Table 4, the resist compositions of Examples 1 to 17 were confirmed to have good sensitivity, CDU, and resolution.

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 comprising a constituent unit (a0) derived from a compound represented by the following general formula (a0). 【Chemistry 1】 [In the formula, W ０ represents a polymerizable group; X ０ represents a hydrogen atom or an alkyl group; Ar ０１ represents an arylene group which may have substituents; La ０１ represents a single bond or a divalent linking group; Rpg ０ represents an acid-dissociable group; n0 represents an integer of 2 or more, as long as the valence allows. Multiple RPGs ０ They may be the same or they may be different.

2. In the above general formula (a0), Rpg ０ The resist composition according to claim 1, wherein the acid-dissociable group is represented by the following general formula (a0-r2). 【Chemistry 2】 [In the formula, Ra' ０１ is a hydrocarbon group. Ya ０ is a carbon atom. Xa ０ is a group that forms an aliphatic cyclic group together with Ya ０ . Some or all of the hydrogen atoms of this cyclic aliphatic cyclic group may be substituted. * indicates a bond.]

3. In the above general formula (a0), Rpg ０ The resist composition according to claim 2, wherein the acid-dissociable group is represented by the following general formula (a0-r2-3). 【Transformation 3】 [In formula (a0-r2-03), Yac ０ Xac is a carbon atom. ０ Yac ０ It is a group that forms an aliphatic cyclic group together with Ra. ００５ This is an aromatic hydrocarbon group that may have substituents. * indicates a bond.

4. In the above general formula (a0), Rpg ０ The resist composition according to claim 1, wherein the acid-dissociable group is represented by the following general formula (a0-r3). 【Chemistry 4】 [In the formula, Ra ０８１ and Ra ０９１ Each is independently either a hydrogen atom or a hydrocarbon group. Y' is a carbon atom. X' is a group that, together with Y', forms a cyclic hydrocarbon group. Some or all of the hydrogen atoms in this cyclic hydrocarbon group may be substituted. Ra ０８１ And, Ra ０９１ These may be joined together to form a ring. * indicates a bonding hand.

5. In the above general formula (a0), W ０ The resist composition according to claim 1, wherein the polymerizable group having a phenolic hydroxyl group is a polymerizable group containing a phenolic hydroxyl group.

6. 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; exposing the resist film; and developing the exposed resist film to form a resist pattern.

7. A compound represented by the following general formula (m0). 【Transformation 5】 [In the formula, W ０ represents a polymerizable group; X ０ represents a hydrogen atom or an alkyl group; Ar ０１ represents an arylene group which may have substituents; La ０１ represents a single bond or a divalent linking group; Rpg ０ represents an acid-dissociable group; n0 represents an integer of 2 or more, as long as the valence allows. Multiple RPGs ０ They may be the same or they may be different.

8. A polymer compound having a constituent unit (a0) derived from the compound described in claim 7.

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