Resist composition, resist pattern forming method, and polymer compound

Abstract

To provide a resist composition or the like which is good in both sensitivity and roughness.SOLUTION: A resist composition generates an acid upon exposure, changes its solubility in a developer by the action of an acid, and contains a resin component (A1) which changes its solubility in a developer by the action of an acid. The resin component (A1) has a constituent unit (a01) represented by a formula (a01) and a constituent unit (a02) represented by a formula (a02).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resist composition, a method for forming a resist pattern, and a polymer compound.

Background Art

[0002] In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, pattern miniaturization has been rapidly progressing due to the advancement of lithography technology. As a miniaturization technique, generally, the wavelength of the exposure light source is shortened (energy is increased).

[0003] Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with fine dimensions. As a resist material that satisfies such requirements, a chemically amplified resist composition containing a base material component whose solubility in a developer changes by the action of an acid and an acid generator component that generates an acid upon exposure has been conventionally used.

[0004] In the chemically amplified resist composition, as the base material component, a resin having a structural unit containing an acid-decomposable group whose polarity increases by the action of an acid is used. For example, Patent Document 1 discloses a resist composition containing a resin having a structural unit having a styrene carboxylic acid skeleton as a structural unit containing an acid-decomposable group.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As the miniaturization of resist patterns progresses, for example, in lithography using EUV (extreme ultraviolet light) or EB (electron beam), the formation of fine patterns with a size of several tens of nm is targeted. Along with such miniaturization of resist patterns, there is a demand for a resist composition having good lithography characteristics such as roughness while maintaining good sensitivity. However, sensitivity and roughness usually have a trade-off relationship, and when either characteristic is improved, the other characteristic tends to deteriorate.

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a resist composition having good sensitivity and roughness, a method for forming a resist pattern using the resist composition, and a polymer compound that can be used in the resist composition.

Means for Solving the Problems

[0008] In order to solve the above problems, the present invention employs the following configuration. That is, a first aspect of the present invention is a resist composition that generates an acid upon exposure and whose solubility in a developer changes by the action of the acid, containing a resin component (A1) whose solubility in a developer changes by the action of the acid, and the resin component (A1) has a structural unit (a01) represented by the following general formula (a01) and a structural unit (a02) represented by the following general formula (a02).

[0009]

Chemical formula

[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 polymer compound having a structural unit (a01) represented by the following general formula (a01) and a structural unit (a02) represented by the following general formula (a02).

[0012] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Ar 01 represents an aromatic hydrocarbon group which may have a substituent. m0 represents an integer of 1 or more as long as the valence allows. Y 02 represents a single bond or a divalent linking group. Rf 02 represents a divalent linking group containing a fluorine atom. m is an integer of 1 or more, and M m+ is an m-valent cation. [Advantages of the Invention]

[0013] According to the present invention, it is possible to provide a resist composition having both good sensitivity and roughness, a resist pattern forming method using the resist composition, and a polymer compound usable in the resist composition. [Modes for Carrying Out the Invention]

[0014] In the present specification and the claims, "aliphatic" is a relative concept with respect to aromatic, and is defined to mean a group, a compound, etc. having no aromaticity. "Alkyl group" shall include linear, branched, and cyclic monovalent saturated hydrocarbon groups unless otherwise specified. The same applies to the alkyl group in an alkoxy group. "Alkylene group" shall include linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified. "Halogen atom" includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. "Constituent unit" means a monomer unit (monomeric unit) that constitutes a polymer 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.

[0015] "Acid-decomposable group" is a group having acid-decomposability such that 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 the acid-decomposable group whose polarity increases by the action of an acid include a group that decomposes by the action of an acid to generate a polar group. Examples of the polar group include a carboxy group, a hydroxy group, an amino group, a sulfo group (-SO3H), and the like. More specifically, examples of the acid-decomposable group include a group 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).

[0016] "Acid-dissociable group" means both (i) a group having acid-dissociability such that the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group can be cleaved by the action of an acid, or (ii) a group in which, after a part of the bonds are cleaved by the action of an acid, a decarboxylation reaction further occurs, whereby the bond between the acid-dissociable group and the atom adjacent to the acid-dissociable group can be cleaved. 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, increasing the polarity. As a result, the polarity of the entire (A1) component 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.

[0017] The "substrate component" is an organic compound having film-forming ability. The organic compounds used as the substrate component are roughly classified into non-polymers and polymers. As non-polymers, those with a molecular weight of usually 500 or more and less than 4000 are used. Hereinafter, when referring to a "low molecular compound", it means a non-polymer with a molecular weight of 500 or more and less than 4000. As polymers, those with a molecular weight of usually 1000 or more are used. Hereinafter, when referring to a "resin", "high molecular compound" or "polymer", it means a polymer with a molecular weight of 1000 or more. The molecular weight of the polymer shall be the weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography).

[0018] 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. In the "acrylic acid ester", the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent. The substituent (R αx ) is an atom or group other than a hydrogen atom. Also, it shall include itaconic acid diesters in which the substituent (R αx ) is substituted with a substituent containing an ester bond, and α-hydroxyacrylic esters in which the substituent (R αx ) is substituted with a hydroxyalkyl group or a group obtained by modifying its hydroxyl group. Note that the α-position carbon atom of the acrylic acid ester is, unless otherwise specified, the carbon atom to which the carbonyl group of acrylic acid is bonded. Hereinafter, an acrylic ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic ester.

[0019] The term "derivative" refers to a concept that includes those in which a hydrogen atom at the α-position of the target compound is substituted with another substituent such as an alkyl group or a halogenated alkyl group, as well as derivatives thereof. Examples of such derivatives include those in which a hydrogen atom of the hydroxyl group of the target compound, which may have a hydrogen atom at the α-position substituted with a substituent, is substituted with an organic group; those in which a substituent other than a hydroxyl group is bonded to the target compound, which may have a hydrogen atom at the α-position substituted with a substituent, and the like. Here, the α-position refers to the first carbon atom adjacent to the functional group, unless otherwise specified. Examples of the substituent that substitutes the hydrogen atom at the α-position of hydroxystyrene include those similar to R αx as described above.

[0020] In this specification and the claims of the present patent, depending on the structure represented by the chemical formula, there may be an asymmetric carbon, and enantiomers or diastereomers may exist. In that case, those isomers are represented by one chemical formula. Those isomers may be used alone or as a mixture.

[0021] (Resist composition) The resist composition according to the first aspect of the present invention generates an acid upon exposure and changes its solubility in a developer by the action of the acid. Such a resist composition contains a base material component (A) (hereinafter also referred to as “component (A)”) whose solubility in a developer changes by the action of an acid. In the resist composition of the present embodiment, component (A) contains a resin component (hereinafter, this resin component is also referred to as “component (A1)”) that generates an acid upon exposure and whose solubility in a developer changes by the action of the acid. Component (A1) has a structural unit (a01) represented by the general formula (a01) described below and a structural unit (a02) represented by the general formula (a02) described below. The structural unit (a01) is a structural unit containing a proton source. The structural unit (a02) is a structural unit that generates an acid upon exposure. In addition to component (A1), the resist composition of the present embodiment may further contain a compound that generates an acid upon exposure (hereinafter also referred to as “component (B)”).

[0022] When a resist film is formed using the resist composition of the present embodiment and selective exposure is performed on the resist film, an acid is generated from component (A) in the exposed portion of the resist film, and the solubility of component (A) in the developer changes due to the action of the acid. On the other hand, in the unexposed portion of the resist film, the solubility of component (A) in the developer does not change. Therefore, a difference in solubility in the developer occurs between the exposed portion and the unexposed portion. Therefore, when the resist film is developed, when the resist composition is positive, the exposed portion of the resist film is dissolved and removed to form a positive resist pattern, and when the resist composition is negative, the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern.

[0023] In this specification, a resist composition in which the exposed portion of the resist film is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern is referred to as a negative resist composition. The resist composition of the present embodiment may be a positive resist composition or a negative resist composition. Further, the resist composition of the present embodiment may be for an alkali development process using an alkali developer for the development process during resist pattern formation, or may be for a solvent development process using a developer containing an organic solvent (organic-based developer) for the development process.

[0024] <Base material component (A)> In the resist composition of the present embodiment, it is preferable to use, as the component (A), a resin component (A1) ((A1) component) whose solubility in a developer changes by the action of an acid. By using the (A1) component, since the polarity of the base material component changes before and after exposure, good development contrast can be obtained not only in the alkali development process but also in the solvent development process. As the component (A), other high molecular compounds and / or low molecular compounds may be used in combination with the (A1) component.

[0025] In the resist composition of the present embodiment, the component (A) may be used alone or in combination of two or more.

[0026] ·Regarding the (A1) component The (A1) component is a resin component whose solubility in a developer changes by the action of an acid. The (A1) component has a structural unit (a01) represented by the general formula (a01) described later and a structural unit (a02) represented by the general formula (a02) described later. As the (A1) component, those having a structural unit (a1) containing an acid-decomposable group whose polarity increases by the action of an acid are preferable. The (A1) component may have other structural units as necessary in addition to the structural unit (a01), the structural unit (a02), and the structural unit (a1).

[0027] ≪Constituent unit (a01)≫ The constituent unit (a01) is a constituent unit represented by the following general formula (a01).

[0028] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Ar 01 represents an aromatic hydrocarbon group which may have a substituent. m0 represents an integer of 1 or more as long as the valence allows.]

[0029] In the formula (a01), the alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. can be mentioned. The halogenated alkyl group having 1 to 5 carbon atoms in R is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of easy availability in industry, a hydrogen atom or a methyl group is most preferable.

[0030] In the formula (a01), Ar 0Examples of the aromatic hydrocarbon group in [description] include a group obtained by removing two hydrogen atoms from an aromatic ring which may have a substituent. The aromatic ring herein is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Ar 0 Examples of the aromatic hydrocarbon group in [description] also include a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings which may have a substituent (for example, biphenyl, fluorene, etc.). Among the above, Ar 0 is preferably a group obtained by removing two hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, more preferably a group obtained by removing two hydrogen atoms from benzene or naphthalene, and still more preferably a group obtained by removing two hydrogen atoms from benzene.

[0031] Ar 0 The aromatic hydrocarbon group in [description] may or may not have a substituent. Examples of the substituent include a hydroxy group, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and the like. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and still more preferably a methoxy group or an ethoxy group. As the halogen atom as the substituent, a fluorine atom is preferable. Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, still more preferably an ethyl group or a methyl group, and particularly preferably a methyl group. Ar 0 The aromatic hydrocarbon group in Ar preferably has no substituent.

[0032] In the formula (a01), Ar 01 Examples of the aromatic hydrocarbon group in Ar include groups obtained by removing (m0 + 1) hydrogen atoms from an aromatic ring which may have a substituent. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Ar 01 Examples of the aromatic hydrocarbon group in Ar also include groups obtained by removing (m0 + 1) hydrogen atoms from an aromatic compound containing two or more aromatic rings which may have a substituent (for example, biphenyl, fluorene, etc.). Among the above, Ar 01 is preferably a group obtained by removing two or more hydrogen atoms from benzene, naphthalene, anthracene or biphenyl, more preferably a group obtained by removing two or more hydrogen atoms from benzene or naphthalene, and still more preferably a group obtained by removing two or more hydrogen atoms from benzene.

[0033] Ar 01The aromatic hydrocarbon group in [it] may or may not have a substituent. As the said substituent, those similar to the substituent in the aromatic hydrocarbon group in the said Ar 0 are exemplified. The said substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, still more preferably an ethyl group or a methyl group, and particularly preferably a methyl group. Ar 01 The aromatic hydrocarbon group in [it] preferably has no substituent.

[0034] In the said formula (a01), m0 is an integer of 1 or more as long as the valence permits, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably 1, 2 or 3, and particularly preferably 1 or 2.

[0035] The constitutional unit (a01) is preferably a constitutional unit represented by the following general formula (a01-1).

[0036]

Chemical formula

[0037] R, Ar 01 in the said formula (a01-1), and m0 are the same as R, Ar 01 in the said formula (a01), and m0 respectively.

[0038] As the substituent in R 011 in the said formula (a01-1), those in Ar 0Those similar to those listed as substituents of the aromatic hydrocarbon group in [are listed].

[0039] In the formula (a01-1) above, m011 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0040] Specific examples of the structural unit (a01) are shown below, but are not limited thereto. In the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0041] [Chemical formula]

[0042] The structural unit (a01) contained in the component (A1) may be one kind or two or more kinds. The proportion of the structural unit (a01) in the component (A1) is preferably 20 to 80 mol%, more preferably 25 to 70 mol%, still more preferably 30 to 60 mol%, and particularly preferably 30 to 50 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). By setting the proportion of the structural unit (a01) to be not less than the lower limit value, the sensitivity is more likely to be increased and the roughness is more likely to be reduced. On the other hand, by setting it to be not more than the upper limit value, it becomes easier to balance with other structural units.

[0043] The proportion of the structural unit (a01) with respect to the total (100 mol%) of the structural unit (a01) and the structural unit (a10) described later is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, even more preferably 90 to 100 mol%, and particularly preferably 100 mol%. By setting the proportion of the structural unit (a01) to be not less than the lower limit value with respect to the total (100 mol%) of the structural unit (a01) and the structural unit (a10) described later, the sensitivity is more likely to be increased and the roughness is more likely to be reduced.

[0044] <<Structural unit (a02)>> The structural unit (a02) is a structural unit represented by the following general formula (a02).

[0045] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Y 02 represents a single bond or a divalent linking group. Rf 02 represents a divalent linking group containing a fluorine atom. m is an integer of 1 or more, and M m+ is an m-valent cation.]

[0046] {Anion part} R and Ar in the formula (a02) 0 are the same as R and Ar in the formula (a01) 0 respectively.

[0047] In the formula (a02), the divalent linking group in Y 02 is not particularly limited, but examples of suitable ones include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a heteroatom, and the like.

[0048] ·Divalent hydrocarbon group which may have a substituent: The divalent hydrocarbon group which may have a substituent may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0049] ··Aliphatic hydrocarbon group The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in its structure, and the like.

[0050] ···Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferred. Specifically, examples include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], and the like. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred. Specifically, examples include alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-, and other alkylalkylene groups. The alkyl group in the alkylalkylene group preferably has 1 to 5 carbon atoms and is a linear alkyl group.

[0051] The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group, and the like.

[0052] ···an aliphatic hydrocarbon group containing a ring in the structure Examples of the aliphatic hydrocarbon group containing a ring in the structure include a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which may contain a substituent containing a hetero atom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, and the like. 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, more preferably 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically, cyclopentane, cyclohexane and the like can be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specifically, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane and the like can be mentioned.

[0053] The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group are more preferable. As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a tert-butoxy group are more preferable, and a methoxy group, an ethoxy group are even more preferable. As the halogen atom as the substituent, a fluorine atom is preferable. Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. Preferred examples of the substituent containing a hetero atom include -O-, -C(=O)-O-, -S-, -S(=O)2-, and -S(=O)2-O-. Specifically, examples include groups obtained by removing one hydrogen atom from the lactone-containing cyclic groups represented by general formulas (a2-r-1) to (a2-r-7) described below, groups obtained by removing one hydrogen atom from the -SO2-containing cyclic groups represented by general formulas (b5-r-1) to (b5-r-4) described below, and groups obtained by removing one hydrogen atom from the heterocyclic groups represented by chemical formulas (r-hr-1) to (r-hr-16) described below.

[0054] ··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 number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and particularly preferably 6 to 12. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with hetero atoms. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Specific examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (such as biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group) is substituted with an alkylene group (for example, a group obtained by further removing one hydrogen atom from the 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 of 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.

[0055] In the aromatic hydrocarbon group, the hydrogen atoms of the aromatic hydrocarbon group may be 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 the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, etc. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group is more preferable. Examples of the alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

[0056] · Divalent linking group containing a heteroatom: Examples of the divalent linking group containing a heteroatom include -O-, -C(=O)-O-, -O-C(=O)-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), -S-, -S(=O)2-, -S(=O)2-O-, general formula -Y 21 -O-Y22 -,-Y 21 -O-,-Y 21 -C(=O)-O-,-C(=O)-O-Y 21 -,-[Y 21 -C(=O)-O] m” -Y 22 -,-Y 21 -O-C(=O)-Y 22 -or -Y 21 -S(=O)2-O-Y 22 -represented group [wherein, Y 21 and Y 22 are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m” is an integer of 1 to 3.] etc. may be mentioned. When the divalent linking group containing the hetero atom is -C(=O)-NH-,-C(=O)-NH-C(=O)-,-NH-,-NH-C(=NH)-, the H thereof may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms. General formula -Y 21 -O-Y 22 -,-Y 21 -O-,-Y 21 -C(=O)-O-,-C(=O)-O-Y 21 -,-[Y 21 -C(=O)-O] m” -Y 22 -,-Y 21 -O-C(=O)-Y 22 -or -Y 21 -S(=O)2-O-Y 22 -in, Y 21 and Y 22 are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group are the same as those described above. Y 21 is preferably a cyclic aliphatic hydrocarbon group or an aromatic hydrocarbon group, and more preferably an aromatic hydrocarbon group. Y 22As for this, a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group or an alkylmethylene group is more preferable. 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 group represented by -, m” is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. Formula -[Y 21 -C(=O)-O] m” -Y 22 As the group represented by -, a group represented by the formula -Y 21 -C(=O)-O-Y 22 - is particularly preferable. Among them, a group represented by the formula -(CH2) a’ -C(=O)-O-(CH2) b’ - is preferable. 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.

[0057] In the formula (a02), as the divalent linking group containing a fluorine atom in Rf 02 , a linear or branched fluorinated alkylene group and a fluorinated arylene group can be mentioned. Rf 02 As the linear fluorinated alkylene group in, the number of carbon atoms is preferably 1 to 10, more preferably 1 to 6, still more preferably 1 to 4, still more preferably 1 to 3, and particularly preferably 1 or 2. Rf 02 As the branched fluorinated alkylene group in, the number of carbon atoms is preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, still more preferably 2 to 3, and particularly preferably 2.

[0058] Rf 02 As the fluorinated arylene group in 02 , a group obtained by removing two hydrogen atoms from an aromatic ring in which one or more hydrogen atoms are substituted with fluorine atoms is preferable. The aromatic ring may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still 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; aromatic heterocyclic rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom, and the like. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include, but are not limited to, a pyridine ring, a thiophene ring, and a furan ring. As the aromatic ring, benzene or naphthalene is preferable, and benzene is more preferable. As the fluorinated arylene group, a perfluoroarylene group is preferable, a perfluorophenylene group or a perfluoronaphthylene group is more preferable, and a perfluorophenylene group is still more preferable.

[0059] As the constitutional unit (a02), a constitutional unit represented by the following general formula (a02-1) is preferable.

[0060]

Chemical formula

[0061] R and Ar in the formula (a02-1) 0 are the same as R and Ar in the formula (a02), respectively. 0

[0062] In the formula (a02-1), Ra 021 The cyclic group which may have a substituent in is preferably a cyclic hydrocarbon group. The cyclic hydrocarbon group may be an aromatic hydrocarbon group or a cyclic aliphatic hydrocarbon group. The cyclic aliphatic hydrocarbon group is preferably saturated.

[0063] Ra 021 The aromatic hydrocarbon group in is a hydrocarbon group having an aromatic ring. The number of carbon atoms of the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, still more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Ra 021 The aromatic ring of the aromatic hydrocarbon group in may be polycyclic or monocyclic. Specific examples of the aromatic ring include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic ring in which a part of the carbon atoms constituting these aromatic rings is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Ra 021 Specific examples of the aromatic hydrocarbon group in include a group obtained by removing two hydrogen atoms from the aromatic ring (arylene group: for example, phenylene group, naphthylene group, etc.).

[0064] Ra 021 The aromatic hydrocarbon group in may have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxy group, a nitro group, etc. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms. ​As the alkoxy group as a substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a tert-butoxy group are more preferable, and a methoxy group and an ethoxy group are most preferable. As the halogen atom as a substituent, a fluorine atom, a bromine atom, and an iodine atom are preferable. As the halogenated alkyl group as a substituent, there may be mentioned a group in which a part or all of hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, etc., are substituted with the above halogen atom.

[0065] Ra 021 The aromatic hydrocarbon group in preferably has an iodine atom as a substituent. Examples of the number of iodine atoms as a substituent include 1 to 3, and 1 or 2 is preferable.

[0066] Ra 021 The cyclic aliphatic hydrocarbon group in includes an aliphatic hydrocarbon group containing a ring in its structure. Examples of the aliphatic hydrocarbon group containing a ring in its structure include an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a group 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. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two or more hydrogen atoms from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specifically, cyclopentane, cyclohexane and the like can be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and as the polycycloalkane, those having 7 to 30 carbon atoms are preferable. Among them, as the polycycloalkane, polycycloalkanes having a bridged-ring polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane; polycycloalkanes having a condensed-ring polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferable.

[0067] Ra 021 The cyclic aliphatic hydrocarbon group in Ra is preferably a group obtained by removing two hydrogen atoms from monocycloalkane or polycycloalkane, more preferably a group obtained by removing two hydrogen atoms from polycycloalkane, still more preferably an adamantandiyl group or a norbornandiyl group, and particularly preferably an adamantandiyl group.

[0068] Ra 021 The cyclic aliphatic hydrocarbon group in Ra may contain a hetero atom such as a heterocyclic ring. Specifically, a group obtained by removing one hydrogen atom from a lactone-containing cyclic group represented by general formulas (a2-r-1) to (a2-r-7) described later, a group obtained by removing one hydrogen atom from a -SO2-containing cyclic group represented by general formulas (b5-r-1) to (b5-r-4) described later, and a group obtained by removing one hydrogen atom from a heterocyclic group represented by chemical formulas (r-hr-1) to (r-hr-16) described later can be mentioned.

[0069] Ra 021The cyclic aliphatic hydrocarbon group in [description] may have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a nitro group, etc. Specific examples of these substituents are the same as those listed as the substituents of the aromatic hydrocarbon group in Ra 021 The same groups as those listed as the substituents of the aromatic hydrocarbon group in [description] can be mentioned. A group obtained by removing one hydrogen atom from [description] can be mentioned.

[0070] Ra 021 is preferably an aromatic hydrocarbon group, and more preferably an aromatic hydrocarbon group containing an iodine atom as a substituent.

[0071] Y in the formula (a02-1) 021 The divalent linking group containing an oxygen atom in [description] may contain atoms other than the oxygen atom. Examples of the atoms other than the oxygen atom include a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom, etc. Y 021 Examples of the divalent linking group containing an oxygen atom in [description] include non-hydrocarbon-based oxygen atom-containing linking groups such as an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxycarbonyl group (-O-C(=O)-), an amide bond (-C(=O)-NH-), a carbonyl group (-C(=O)-), a carbonate bond (-O-C(=O)-O-); combinations of the non-hydrocarbon-based oxygen atom-containing linking group and an alkylene group, etc. A sulfonyl group (-SO2-) may be further linked to this combination.

[0072] Y 021 Examples of Y include linking groups represented by the following general formulas (L-al-1) to (L-al-8). In the following general formulas (L-al-1) to (L-al-8), Ra in the formula (a02-1) 021 binds to V' in the following general formulas (L-al-1) to (L-al-8). 101 is as follows.

[0073]

Chemical formula

[0074] The divalent saturated hydrocarbon group in V' 102 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.

[0075] The alkylene group in V' 101 and V' 102 may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferred. Specific examples of the alkylene group in V' 101 and V' 102 include a methylene group [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; an ethylene group [-CH2CH2-]; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-; a trimethylene group (n-propylene group) [-CH2CH2CH2-]; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; a tetramethylene group [-CH2CH2CH2CH2-]; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-; a pentamethylene group [-CH2CH2CH2CH2CH2-], and the like. In addition, some of the methylene groups in the alkylene group in V' 101 or V' 102 may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is Ra' in the formula (a1-r-1) 3A divalent group obtained by further removing one hydrogen atom from a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group) is preferred, and a cyclohexylene group, a 1,5-adamantylene group or a 2,6-adamantylene group is more preferred.

[0076] Y 021 As [it], a divalent linking group containing an ester bond or a divalent linking group containing an ether bond is preferred, and the linking groups represented by the above formulas (L-al-1) to (L-al-5), (L-al-8) are more preferred, and the linking group represented by the above formula (L-al-3) or (L-al-8) is even more preferred.

[0077] In the above formula (a02-1), V 021 The alkylene group or fluorinated alkylene group in [it] may be linear or branched, but a linear one is preferred. The alkylene group or fluorinated alkylene group in V 021 Examples of the alkylene group or fluorinated alkylene group in [it] include an alkylene group or fluorinated alkylene group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 or 2 carbon atoms. V 021 is preferably a single bond or a linear alkylene group.

[0078] In the above formula (a02-1), Rf 021 The fluorinated alkylene group in [it] may be linear or branched, but a linear one is preferred. The fluorinated alkylene group in Rf 021 Examples of the fluorinated alkylene group in [it] include those having 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms, and even more preferably 1 carbon atom. The fluorinated alkylene group in Rf 021 Specific examples of the fluorinated alkylene group in [it] include -CF2-, -CHF-, -CF(CF3)-, -CF2CF2-, -CHFCF2-, -CH(CF3)CF2- and the like.

[0079] In the above formula (a02-1), the fluorinated arylene group in Rf 021 is the same as the Rf in the above formula (a02) 02Examples of those similar to the fluorinated arylene group include those where the aromatic ring contained may be a monocyclic or polycyclic aromatic ring. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings where some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. As the fluorinated arylene group, a perfluoroarylene group is preferred, a perfluorophenylene group or a perfluoronaphthylene group is more preferred, and a perfluorophenylene group is even more preferred.

[0080] As the constitutional unit (a02), a constitutional unit represented by the following general formula (a02-11) is preferred.

[0081] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R 021 represents a substituent. Ra 021 represents a single bond or a cyclic group which may have a substituent. Y 021 represents a divalent linking group containing an oxygen atom or a single bond. V 021 represents a single bond, an alkylene group or a fluorinated alkylene group. Rf 021 represents a fluorinated alkylene group or a fluorinated arylene group. m021 represents an integer of 0 to 4. When m021 is an integer of 2 or more, two or more R 021 may be the same as or different from each other. m is an integer of 1 or more, and M m+ is an m-valent cation.]

[0082] R, Ra 021 , Y 021 , V 021 , and Rf 021 in the formula (a02-11) are the same as R, Ra 021 in the formula (a02-1), Y021 , V 021 , and Rf 021 is the same as each of them.

[0083] R in the formula (a02 - 11) 021 As the substituent in, the same ones as those exemplified as the substituent of the aromatic hydrocarbon group in Ar in the formula (a01) 0 are exemplified.

[0084] In the formula (a02 - 11), m021 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0085] Specific examples of the anion part of the constitutional unit (a02) are shown below, but are not limited thereto. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[0086]

Chemical formula

[0087]

Chemical formula

[0088] {Cation part} In the formula (a2), M m+ represents an m-valent onium cation. Among these, M m+ is preferably a sulfonium cation or an iodonium cation. m is an integer of 1 or more.

[0089] Preferred cation parts ((M m+ )) 1 / m ) include organic cations respectively represented by the following general formulas (ca - 1) to (ca - 3).

[0090]

Chemical formula

[0091] In the above general formulas (ca-1) to (ca-3), R 201 ~R 207 Examples of the aryl group include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferred. R 201 ~R 207 Examples of the alkyl group include a linear or cyclic alkyl group, and those having 1 to 30 carbon atoms are preferred. R 201 ~R 207 The alkenyl group preferably has 2 to 10 carbon atoms. R 201 ~R 207 、およびR 210 Examples of the substituent which may be possessed by, and include, for example, an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, a group represented by each of the following general formulas (ca-r-1) to (ca-r-7), etc.

[0092]

Chemical formula

[0093] Cyclic group which may have a substituent: The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0094] R’ 201 The aromatic hydrocarbon group in R’ is a hydrocarbon group having an aromatic ring. The number of carbon atoms of the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, still more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. R’ 201 Specific examples of the aromatic ring of the aromatic hydrocarbon group in R’ include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic ring in which a part of the carbon atoms constituting these aromatic rings is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, a nitrogen atom, etc. R’ 201 Specific examples of the aromatic hydrocarbon group in R’ include a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc., arylalkyl groups). The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0095] R’ 201 The cyclic aliphatic hydrocarbon group in 201 includes aliphatic hydrocarbon groups containing a ring in the structure. Examples of the aliphatic hydrocarbon group containing a ring in this structure include alicyclic hydrocarbon groups (groups obtained by removing one hydrogen atom 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, groups in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, and the like. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically includes cyclopentane, cyclohexane, and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, as the polycycloalkane, polycycloalkanes having a crosslinked ring system polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane; and polycycloalkanes having a condensed ring system polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferred.

[0096] Among them, as the cyclic aliphatic hydrocarbon group in R’ 201 a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane is preferred, a group obtained by removing one hydrogen atom from a polycycloalkane is more preferred, an adamantyl group and a norbornyl group are particularly preferred, and an adamantyl group is most preferred.

[0097] The linear or branched aliphatic hydrocarbon group, which may be bonded to an alicyclic hydrocarbon group, preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], etc. can be mentioned. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2-, etc. can be mentioned. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

[0098] Also, R' 201 The cyclic hydrocarbon group in may contain a hetero atom such as a heterocyclic ring. Specifically, a lactone-containing cyclic group represented by the general formulas (a2-r-1) to (a2-r-7) described later, a -SO2-containing cyclic group represented by the general formulas (b5-r-1) to (b5-r-4) described later, and a heterocyclic group represented by the following chemical formulas (r-hr-1) to (r-hr-16) can be mentioned.

[0099]

Chemical formula

[0100] R’ 201 Examples of the substituent in the cyclic group of 201 include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, and the like. As the alkyl group as a substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are most preferable. As the alkoxy group as a substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, 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 preferable, and a methoxy group and an ethoxy group are most preferable. As the halogen atom as a substituent, a fluorine atom is preferable. Examples of the halogenated alkyl group as a substituent include a group in which part or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group, are substituted with the halogen atom. The carbonyl group as a substituent is a group that substitutes the methylene group (-CH2-) constituting the cyclic hydrocarbon group.

[0101] The chain-like alkyl group which may have a substituent: R’ 201 The chain-like alkyl group of 201 may be either linear or branched. As the linear alkyl group, it is preferably having 1 to 20 carbon atoms, more preferably having 1 to 15 carbon atoms, and most preferably having 1 to 10 carbon atoms. As the branched alkyl group, it is preferably having 3 to 20 carbon atoms, more preferably having 3 to 15 carbon atoms, and most preferably having 3 to 10 carbon atoms. Specifically, for example, 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, 4-methylpentyl group, and the like can be mentioned.

[0102] A chain alkenyl group which may have a substituent: R’ 201 The chain alkenyl group of 201 may be either linear or branched, preferably having 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, still more preferably 2 to 4 carbon atoms, and particularly preferably 3 carbon atoms. Examples of the linear alkenyl group include vinyl group, propenyl group (allyl group), butenyl group, etc. Examples of the branched alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group, etc. Among them, as the chain alkenyl group, a linear alkenyl group is preferred, a vinyl group or a propenyl group is more preferred, and a vinyl group is particularly preferred.

[0103] R’ 201 Examples of the substituent in the chain alkyl group or alkenyl group of 201 include alkoxy group, halogen atom, halogenated alkyl group, hydroxyl group, carbonyl group, nitro group, amino group, and the cyclic group in the above R’ 201 etc.

[0104] R’ 201 The cyclic group which may have a substituent, the chain alkyl group which may have a substituent, or the chain alkenyl group which may have a substituent, in addition to those described above, as the cyclic group which may have a substituent or the chain alkyl group which may have a substituent, also includes those similar to the acid dissociable group represented by the following formula (a1-r-2).

[0105] Among them, R’ 201 Preferably has a cyclic group which may have a substituent, and more preferably is a cyclic hydrocarbon group which may have a substituent. More specifically, for example, a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane; a lactone-containing cyclic group represented by the following general formulas (a2-r-1) to (a2-r-7) respectively; a -SO2-containing cyclic group represented by the following general formulas (b5-r-1) to (b5-r-4) respectively, etc. are preferred.

[0106] In the above general formulas (ca-1) to (ca-3), R 201 ~R 203 , R 206 ~R 207 When they are bonded to each other to form a ring together with the sulfur atom in the formula, they do not include a heteroatom such as a sulfur atom, an oxygen atom, or a nitrogen atom, a carbonyl group, -SO-, -SO2-, -SO3-, -COO-, -CONH-, or -N(R N )-(the R N is an alkyl group having 1 to 5 carbon atoms.) The ring formed is preferably a 3- to 10-membered ring, including the sulfur atom, and particularly preferably a 5- to 7-membered ring, in which a ring containing a sulfur atom in the ring skeleton in the formula is a 3- to 10-membered ring, inclusive of the sulfur atom. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.

[0107] R 208 ~R 209 each 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, and when they are alkyl groups they may be bonded to each other to form a ring.

[0108] R 210 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 The aryl group in the formula (I) may be an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group or a naphthyl group is preferred. R 210 The alkyl group in is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. R 210 The alkenyl group in the formula (I) preferably has 2 to 10 carbon atoms. R210 In the formula, as the -SO2-containing cyclic group, any group can be used without particular limitation. Specifically, groups represented by the following general formulas (b5-r-1) to (b5-r-4) can be mentioned, and a "-SO2-containing polycyclic group" is preferred, and a group represented by the general formula (b5-r-1) is more preferred.

[0109]

Chemical formula

[0110] In the 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, an oxygen atom or a sulfur atom. As B”, 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 even more preferred.

[0111] In the general formulas (b5-r-1) to (b5-r-4), Rb’ 51 is each 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 them, it is preferably each independently a hydrogen atom or a cyano group.

[0112] Specific examples of the groups represented by the general formulas (b5-r-1) to (b5-r-4) are given below. “Ac” in the formula represents an acetyl group.

[0113] [Chemistry]

[0114] [Chemistry]

[0115] [Chemistry]

[0116] Specific examples of the preferred cation represented by the formula (ca-1) include cations represented by the following chemical formulas, respectively.

[0117] [Chemistry]

[0118] [Chemistry]

[0119] [Chemistry] [In the formula, g1, g2, and g3 represent the number of repetitions, g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20.]

[0120] [Chemistry]

[0121] [Chemistry]

[0122] [Chemistry] [In the formula, R” 201is a hydrogen atom or a substituent, and examples of the substituent include the aforementioned R 201 ~R 207 , and the same as those exemplified as the substituents that R 210 ~R 212 may have.]

[0123]

Chemical formula

[0124] Specific examples of the preferred cation represented by the formula (ca-2) include a diphenyliodonium cation, a bis(4-tert-butylphenyl)iodonium cation, and the like.

[0125] Specific examples of the preferred cation represented by the formula (ca-3) include cations respectively represented by the following formulas (ca-3-1) to (ca-3-6).

[0126]

Chemical formula

[0127] As the cation moiety ((M m+ )) 1 / m ) in the formula (a02), a sulfonium cation is preferred, cations respectively represented by the formulas (ca-1) to (ca-3) are more preferred, the cation represented by the formula (ca-1) is still more preferred, and cations respectively represented by the formulas (ca-1-1) to (ca-1-84) are particularly preferred. Particularly from the viewpoint of high sensitivity, as the preferred cation represented by the formula (ca-1), those having an electron-withdrawing group such as a fluorine atom, a fluorinated alkyl group, or a sulfonyl group as a substituent are preferred. For example, cations selected from the group consisting of cations respectively represented by the above chemical formulas (ca-1-44), (ca-1-71) to (ca-1-84) are particularly preferred.

[0128] The structural unit (a02) contained in the component (A1) may be one type or two or more types. (When the component (A1) has the structural unit (a02), the proportion of the structural unit (a02) in the component (A1) is preferably 3 to 25 mol%, more preferably 5 to 20 mol%, still more preferably 8 to 20 mol%, based on the total (100 mol%) of all the structural units constituting the component (A1). When the proportion of the structural unit (a02) is at least the lower limit of the above-mentioned preferred range, it becomes easier to achieve high sensitivity and reduction of roughness. On the other hand, when it is at most the upper limit of the above-mentioned preferred range, it becomes easier to balance with other structural units.

[0129] The proportion of the structural unit (a02) with respect to the total (100 mol%) of the structural unit (a02) and the structural unit (a5) described later is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, even more preferably 90 to 100 mol%, and particularly preferably 100 mol%. By setting the proportion of the structural unit (a02) to be at least the lower limit with respect to the total (100 mol%) of the structural unit (a02) and the structural unit (a5) described later, the sensitivity can be more easily increased and the reduction of roughness can be easily achieved.

[0130] <<Structural unit (a1)>> The structural unit (a1) is a structural unit containing an acid-dissociable group whose polarity increases by the action of an acid. The component (A1) preferably has the structural unit (a1).

[0131] Examples of the acid-dissociable group include those proposed as the acid-dissociable group of the base resin for chemically amplified resist compositions. Specific examples of those proposed as the acid-dissociable group of the base resin for chemically amplified resist compositions include the "acetal-type acid-dissociable group", "tertiary alkyl ester-type acid-dissociable group", "tertiary alkyloxycarbonyl acid-dissociable group", and "secondary alkyloxycarbonyl acid-dissociable group" described below.

[0132] Acetal-type acid-dissociable group: As the acid dissociable group that protects a carboxy group or a hydroxy group among the polar groups, for example, an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as an "acetal type acid dissociable group") can be mentioned.

[0133] [Chemical formula] [In the formula, Ra’ 1 , Ra’ 2 is a hydrogen atom or an alkyl group. Ra’ 3 is a hydrocarbon group, and Ra’ 3 may be bonded to either Ra’ 1 , Ra’ 2 to form a ring.]

[0134] In formula (a1-r-1), it is preferable that at least one of Ra’ 1 and Ra’ 2 is a hydrogen atom, and it is more preferable that both are hydrogen atoms. When Ra’ 1 or Ra’ 2 is an alkyl group, examples of the alkyl group include the same ones as the alkyl groups listed as the substituents that may be bonded to the carbon atom at the α-position in the description of the above α-substituted acrylic acid ester, and an alkyl group having 1 to 5 carbon atoms is preferable. Specifically, a linear or branched alkyl group is preferably mentioned. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. can be mentioned, a methyl group or an ethyl group is more preferable, and a methyl group is particularly preferable.

[0135] In formula (a1-r-1), examples of the hydrocarbon group of Ra’ 3 include a linear or branched alkyl group or a cyclic hydrocarbon group. 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.

[0136] The branched alkyl group preferably has 3 to 10 carbon atoms, 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., and isopropyl group is preferred.

[0137] Ra’ 3 When Ra’ 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 aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically, examples include cyclopentane, cyclohexane, etc. As the aliphatic hydrocarbon group which is a polycyclic group, a group obtained by removing one hydrogen atom from polycycloalkane is preferred. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically, examples include adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane, etc.

[0138] Ra’ 3 When the cyclic hydrocarbon group of Ra’ is 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 has a cyclic conjugated system with 4n + 2 π electrons, and it may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still 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; aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms, and the like. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring, a thiophene ring, and the like. Ra’ 3 Specific examples of the aromatic hydrocarbon group in include a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group); a group obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (such as biphenyl, fluorene, etc.); a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (such as an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0139] Ra’ 3 The cyclic hydrocarbon group in may have a substituent. Examples of this substituent include -RP1, -RP2-O-RP1, -RP2-CO-RP1, -RP2-CO-ORP1, -RP2-O-CO-RP1, -RP2-OH, -RP2-CN, or -RP2-COOH (hereinafter, these substituents are also collectively referred to as "Rax5"). Here, R P1 is a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Also, RP2 is a single bond, a divalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. However, R P1 and R P2 Some or all of the hydrogen atoms of the linear saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group may be substituted with fluorine atoms. The above-mentioned aliphatic cyclic hydrocarbon group may have one or more of the above-mentioned substituents alone, or may have one or more of a plurality of types of the above-mentioned substituents. Examples of the monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, and the like. Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, a cyclododecyl group, etc.; polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7]decanyl group, a tetracyclo[6.2.1.13,6.02,7]dodecanyl group, an adamantyl group, etc. Examples of the monovalent aromatic hydrocarbon group 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, phenanthrene, etc.

[0140] Ra’ 3 When Ra’ 1 and Ra’ 2 are bonded to each other to form a ring, the cyclic group is preferably a 4- to 7-membered ring, more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group, a tetrahydrofuranyl group, and the like.

[0141] Tertiary alkyl ester type acid dissociable group: Among the above polar groups, examples of the acid dissociable group that protects the carboxy group include acid dissociable groups represented by the following general formula (a1-r-2). Among the acid dissociable groups represented by the following formula (a1-r-2), those composed of an alkyl group may be hereinafter referred to as "tertiary alkyl ester type acid dissociable groups" for convenience.

[0142] [Chemical formula] [In the formula, Ra’ 4 ~Ra’ 6 are each a hydrocarbon group, and Ra’ 5 , Ra’ 6 may be bonded to each other to form a ring.]

[0143] Examples of the hydrocarbon group of Ra’ 4 include a linear or branched alkyl group, a linear or cyclic alkenyl group, or a cyclic hydrocarbon group. Examples of the linear or branched alkyl group and cyclic hydrocarbon group (aliphatic hydrocarbon group which is a monocyclic group, aliphatic hydrocarbon group which is a polycyclic group, aromatic hydrocarbon group) in Ra’ 4 are the same as those of the above Ra’ 3 . Examples of the linear or cyclic alkenyl group in Ra’ 4 preferably include an alkenyl group having 2 to 10 carbon atoms. Examples of the hydrocarbon group of Ra’ 5 , Ra’ 6 are the same as those of the above Ra’ 3 .

[0144] When Ra’ 5 and Ra’ 6 are bonded to each other to form a ring, groups represented by the following general formula (a1-r2-1), groups represented by the following general formula (a1-r2-2), and groups represented by the following general formula (a1-r2-3) are preferably mentioned. On the other hand, Ra’ 4 ~Ra’ 6When they are hydrocarbon groups that do not bond to each other and are independent, the group represented by the following general formula (a1-r2-4) is preferably cited.

[0145] [Chemical formula] [In formula (a1-r2-1), Ra’ 10 represents a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with a halogen atom or a heteroatom-containing group. Ra’ 11 is a group that forms an aliphatic cyclic group together with the carbon atom to which Ra’ 10 is bonded. In formula (a1-r2-2), Ya is a carbon atom. Xa is a group that forms a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of this cyclic hydrocarbon group may be substituted. Ra 101 ~Ra 103 are each 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 of this linear saturated hydrocarbon group and aliphatic cyclic saturated hydrocarbon group may be substituted. Ra 101 ~Ra 103 Two or more of them may bond to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group that forms an aliphatic cyclic group together with Yaa. Ra 104 is an aromatic hydrocarbon group that may have a substituent. In formula (a1-r2-4), Ra’ 12 and Ra’ 13 are each independently a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms of this linear saturated hydrocarbon group may be substituted. Ra’ 14 is a hydrocarbon group that may have a substituent. * represents a bond (the same applies hereinafter).]

[0146] In the above formula (a1-r2-1), Ra’ 10 is a linear or branched alkyl group having 1 to 12 carbon atoms, which may be partially substituted with a halogen atom or a heteroatom-containing group.

[0147] Ra’ 10 In the case of a linear alkyl group, the number of carbon atoms is 1 to 12, preferably 1 to 10, and particularly preferably 1 to 5. Ra’ 10 In the case of a branched alkyl group, examples thereof include the same ones as the above Ra’. 3 The same ones as those can be mentioned.

[0148] Ra’ 10 The alkyl group in may be partially substituted with a halogen atom or a heteroatom-containing group. For example, a part of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. Further, a part of the carbon atoms (such as a methylene group) constituting the alkyl group may be substituted with a heteroatom-containing group. Examples of the heteroatom herein include an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of the heteroatom-containing group include (-O-), -C(=O)-O-, -O-C(=O)-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -S-, -S(=O)2-, -S(=O)2-O-, and the like.

[0149] In formula (a1-r2-1), the aliphatic cyclic group formed together with the carbon atom to which Ra’ 11 (Ra’ 10 is bonded) is preferably a group exemplified as the aliphatic hydrocarbon group (alicyclic hydrocarbon group) which is a monocyclic group or a polycyclic group of Ra’ in formula (a1-r-1). Among them, a monocyclic alicyclic hydrocarbon group is preferable, and specifically, a cyclopentyl group and a cyclohexyl group are more preferable. 3 Among them, a monocyclic alicyclic hydrocarbon group is preferable, and specifically, a cyclopentyl group and a cyclohexyl group are more preferable.

[0150] In formula (a1-r2-2), examples of the cyclic hydrocarbon group formed by Xa and Ya together include a group obtained by further removing one or more hydrogen atoms from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) of Ra’ in the above formula (a1-r-1). 3 A group obtained by further removing one or more hydrogen atoms from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) of Ra’ in the above formula (a1-r-1) can be mentioned. The cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. Examples of this substituent include the same substituents as those that the cyclic hydrocarbon group in the above Ra’ 3 may have. In formula (a1-r2-2), examples of the monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms in Ra 101 ~Ra 103 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, and the like. Ra 101 ~Ra 103 Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra 2,6 ~Ra 3,7 include monocyclic aliphatic saturated hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, a cyclododecyl group; polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.0 3,6 .0 2,7 decanyl group, a tricyclo[3.3.1.1 Ra 101 ~Ra 103 Among them, from the viewpoint of ease of synthesis, a hydrogen atom and a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms are preferable, and among them, a hydrogen atom, a methyl group, and an ethyl group are more preferable, and a hydrogen atom is particularly preferable.

[0151] Examples of the substituent of the linear saturated hydrocarbon group or the aliphatic cyclic saturated hydrocarbon group represented by the above Ra 101 ~Ra 103 include, for example, the same groups as those of the above Ra x5 and the like.

[0152] Ra 101 ~Ra 103Examples of the group containing a carbon-carbon double bond formed by the combination of two or more of them to form a cyclic structure include, for example, a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methylcyclohexenyl group, a cyclopentylideneethenyl group, a cyclohexylideneethenyl group, and the like. Among these, from the viewpoint of ease of synthesis, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneethenyl group are preferred.

[0153] In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is preferably the group exemplified as the aliphatic hydrocarbon group which is a monocyclic group or a polycyclic group of Ra' in formula (a1-r-1). 3 In formula (a1-r2-3), Ra 104 Examples of the aromatic hydrocarbon group in include a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra 104 is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene, still more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene, particularly preferably a group obtained by removing one or more hydrogen atoms from benzene or naphthalene, and most preferably a group obtained by removing one or more hydrogen atoms from benzene.

[0154] Examples of the substituent that Ra in formula (a1-r2-3) may have include, for example, a methyl group, an ethyl group, a propyl group, a hydroxy group, a carboxy group, a halogen atom, an alkoxy group (such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, etc.), an alkyloxycarbonyl group, and the like. 104

[0155] In formula (a1-r2-4), Ra' 12 and Ra' 13 are each independently a monovalent chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. Ra' 12 and Ra' 13 ​​In the case of a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, examples of the above Ra 101 ~Ra 103 include the same ones as the monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms in the above. Some or all of the hydrogen atoms of this linear saturated hydrocarbon group may be substituted. Ra’ 12 and Ra’ 13 are preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, still more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. When the linear saturated hydrocarbon group represented by the above Ra’ 12 and Ra’ 13 is substituted, examples of the substituent include, for example, the same groups as the above Ra x5 .

[0156] In formula (a1-r2-4), Ra’ 14 is a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group in Ra’ 14 include a linear or branched alkyl group, or a cyclic hydrocarbon group.

[0157] Ra’ 14 The linear alkyl group in Ra’

[0158] preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and still more preferably 1 or 2 carbon atoms. Specifically, examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, etc. Among these, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable. 14 The branched alkyl group in Ra’

[0159] Ra’14 When it 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 aliphatic hydrocarbon group which is a monocyclic group, a group obtained by removing one hydrogen atom from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specifically, cyclopentane, cyclohexane and the like can be mentioned. As the aliphatic hydrocarbon group which is a polycyclic group, a group obtained by removing one hydrogen atom from polycycloalkane is preferable. As the polycycloalkane, those having 7 to 12 carbon atoms are preferable, and specifically, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane and the like can be mentioned.

[0160] Ra’ 14 As the aromatic hydrocarbon group in, Ra 104 The same ones as the aromatic hydrocarbon group in can be mentioned. Among them, Ra’ 14 Is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene, and further preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene or anthracene, particularly preferably a group obtained by removing one or more hydrogen atoms from naphthalene or anthracene, and most preferably a group obtained by removing one or more hydrogen atoms from naphthalene. Ra’ 14 As the substituent that Ra’ 104 May have, the same ones as the substituent that Ra

[0161] Ra’ in formula (a1-r2-4) 14 When it is a naphthyl group, the position bonding to the tertiary carbon atom in the formula (a1-r2-4) may be either the 1-position or the 2-position of the naphthyl group. Ra’ in formula (a1-r2-4) 14When it is an antryl group, the position bonding to the tertiary carbon atom in the formula (a1-r2-4) may be any of the 1-position, 2-position, or 9-position of the antryl group.

[0162] Specific examples of the group represented by the formula (a1-r2-1) are listed below.

[0163]

Chemical formula

[0164]

Chemical formula

[0165]

Chemical formula

[0166] Specific examples of the group represented by the formula (a1-r2-2) are listed below.

[0167]

Chemical formula

[0168]

Chemical formula

[0169]

Chemical formula

[0170] Specific examples of the group represented by the formula (a1-r2-3) are listed below.

[0171]

Chemical formula

[0172] Specific examples of the group represented by the formula (a1-r2-4) are given below.

[0173]

Chemical formula

[0174] Tertiary alkyloxycarbonyl acid dissociable group: Among the above polar groups, examples of the acid dissociable group that protects the hydroxyl group include the acid dissociable group represented by the following general formula (a1-r-3) (hereinafter sometimes referred to as "tertiary alkyloxycarbonyl acid dissociable group" for convenience).

[0175]

Chemical formula

[0176] In the formula (a1-r-3), Ra’ 7 ~Ra’ 9 are each preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Also, the total number of carbon atoms of each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0177] Secondary alkyl ester type acid dissociable group: Among the above polar groups, examples of the acid dissociable group that protects the carboxy group include the acid dissociable group represented by the following general formula (a1-r-4).

[0178]

Chemical formula

[0179] In the formula, Ra’ 10 and Ra’ 12 Examples of the hydrocarbon group in Ra’ 3 are the same as those of the above Ra’ In the formula, Ra’ 11a and Ra’ 11b Examples of the alkyl group in Ra’ 1 are the same as those of the alkyl group in the above Ra’ In the formula, Ra’ 10 and Ra’ 12 The hydrocarbon group in Ra’ 11a and Ra’ 11b and the alkyl group in Ra’ x5 and Ra’

[0180] Ra’ 10 and Ra’ 11a or Ra’ 11b and Ra’ The ring formed by bonding with each other may be a polycyclic ring or a monocyclic ring, and may be an alicyclic ring or an aromatic ring. The alicyclic ring and the aromatic ring may contain heteroatoms.

[0181] Ra’ 10 and Ra’ 11a or Ra’ 11b Among the above, the rings formed by bonding with each other are preferably monocycloalkene, a ring in which a part of the carbon atoms of monocycloalkene is substituted with heteroatoms (oxygen atom, sulfur atom, etc.), and monocycloalkadiene, preferably cycloalkene having 3 to 6 carbon atoms, and preferably cyclopentene or cyclohexene.

[0182] Ra’ 10 and Ra’ 11a or Ra’ 11b The ring formed by combining with each other may be a condensed ring. Specific examples of the condensed ring include indane and the like.

[0183] Ra’ 10 and Ra’ 11a or Ra’ 11b The ring formed by combining with each other may have a substituent. Examples of this substituent include, for example, Ra x5 and the like.

[0184] Ra’ 11a or Ra’ 11b and Ra’ 12 and Ra’ 10 and Ra’ 11a or Ra’ 11b and may combine with each other to form a ring. Examples of the ring include those similar to the ring formed by combining Ra’

[0185] Specific examples of the group represented by the formula (a1-r-4) are given below.

[0186]

Chemical formula

[0187] Examples of the constitutional unit (a1) include a constitutional unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, a constitutional unit derived from acrylamide, a constitutional unit in which at least a part of the hydrogen atoms in the hydroxyl group of a constitutional unit derived from hydroxystyrene or a hydroxystyrene derivative is protected by a substituent containing the acid-decomposable group, a constitutional unit in which at least a part of the hydrogen atoms in the -C(=O)-OH of a constitutional unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative is protected by a substituent containing the acid-decomposable group, and the like.

[0188] As the structural unit (a1), among the above, a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent is preferable. Preferable specific examples of such a structural unit (a1) include structural units represented by the following general formulas (a1-1), (a1-2), or (a1-3).

[0189] [Chemical formula] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va 1 is a divalent hydrocarbon group which may have an ether bond. n a1 is an integer of 0 to 2. Ra 1 is an acid dissociable group represented by the above general formula (a1-r-1), (a1-r-2), or (a1-r-4). Wa 1 is n a2 + a monovalent hydrocarbon group. n a2 is an integer of 1 to 3. Ra 2 is an acid dissociable group represented by the above general formula (a1-r-1) or (a1-r-3). Ya 001 is a single bond or a divalent linking group. Ya 01 is a single bond or a divalent linking group. Rax 01 is an acid dissociable group represented by the above general formula (a1-r-1), (a1-r-2), or (a1-r-4). Rz 01 is an alkyl group, a halogen atom, a halogenated alkyl group, a hydroxy group, or an alkoxy group. q is an integer of 0 to 3. n is an integer of 0 or more. However, n ≦ q × 2 + 4.]

[0190] In the formulas (a1-1) to (a1-3), the alkyl group having 1 to 5 carbon atoms for R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specifically, examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like. 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. As the halogen atom, a fluorine atom is particularly preferable. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of easy availability in industry, a hydrogen atom or a methyl group is most preferable.

[0191] In the formula (a1-1), Va 1 The divalent hydrocarbon group in may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0192] Va 1 The aliphatic hydrocarbon group as the divalent hydrocarbon group in may be saturated or unsaturated, and is usually preferably saturated. More specifically, examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in its structure.

[0193] The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, examples include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], and the like. The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferred. Specifically, alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2- and other alkylalkylene groups can be mentioned. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0194] Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched-chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched-chain aliphatic hydrocarbon group. Examples of the linear or branched-chain aliphatic hydrocarbon group are the same as those of the linear aliphatic hydrocarbon group or the branched-chain aliphatic hydrocarbon group described above. 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 polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically, cyclopentane, cyclohexane, etc. may be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specifically, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane, etc. may be mentioned.

[0195] Va 1 The aromatic hydrocarbon group as the divalent hydrocarbon group in is a hydrocarbon group having an aromatic ring. Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 12 carbon atoms. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring of the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group in which one hydrogen atom of a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group) is substituted with an alkylene group (for example, a group obtained by further removing one hydrogen atom from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group). The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0196] In the formula (a1-1), Ra 1 is preferably an acid dissociable group represented by the above general formula (a1-r-2) or (a1-r-4). Among these, a group represented by the general formula (a1-r2-1) or an acid dissociable group represented by the general formula (a1-r-4) is more preferable.

[0197] In the formula (a1-2), Wa 1 The n a2 The +1-valent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a group combining a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in the structure. The said n a2 The +1-valent is preferably divalent to tetravalent, more preferably divalent or trivalent. In the formula (a1-2), Ra 2 is preferably an acid dissociable group represented by the above general formula (a1-r-1).

[0198] In the formula (a1-3), Ya 001 The divalent linking group in is not particularly limited, but examples of suitable ones include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom. Ya 001 As, an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, an aromatic hydrocarbon group or a combination thereof, or a single bond is preferable. The number of carbon atoms of the alkylene group is preferably 1 to 10, more preferably 1 to 6, still more preferably 1 to 4, and particularly preferably 1 to 3. Among these, Ya 001As the [bond], a combination of an ester bond [-C(=O)-O-, -O-C(=O)-] and a linear alkylene group, or a single bond is more preferable, and a single bond is even more preferable.

[0199] In the formula (a1-3), Ya 01 The divalent linking group in [the relevant part] is not particularly limited, but examples of preferable ones include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a heteroatom, and the like. Ya 01 Among these, Ya 01 is preferably an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, an aromatic hydrocarbon group, or a combination thereof, or a single bond. Among these, Ya

[0200] In the formula (a1-3), Rax 01 is preferably an acid dissociable group represented by the above general formula (a1-r-2) or (a1-r-4). Among these, an acid dissociable group represented by the general formula (a1-r-2) is more preferable, and a group represented by the general formula (a1-r2-1) is even more preferable.

[0201] In the formula (a1-3), Rz 01 The alkyl group, halogenated alkyl group, and alkoxy group in [the relevant part] 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, halogenated alkyl group, and alkoxy group may be linear or branched. Rz 01 The halogen atom in [the relevant part] is preferably an iodine atom. The halogen atom of the halogenated alkyl group in [the relevant part] 01 is preferably a fluorine atom, an iodine atom, or a bromine atom, and more preferably a fluorine atom. Rz01 is preferably an alkoxy group or a hydroxy group, more preferably a hydroxy group.

[0202] In the formula (a1-3), q is an integer of 0 to 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; when q is 3, it is a tetracene structure. In the formula (a1-3), n is an integer of 0 or more, preferably 0 to 5, more preferably 0 to 3, and still more preferably 1 or 2. When n is an integer of 2 or more, two or more Rz 01 may be the same as or different from each other. In the formula (a1-3), n ≦ q × 2 + 4. For example, when q is 1 and it is a naphthalene structure, all six hydrogen atoms of the naphthalene may be substituted with hydroxy groups. Also, in the naphthalene, Ya 001 , -Ya 01 -C(=O)-O-Ra 01 groups, and the substitution positions of the hydroxy groups are not particularly limited.

[0203] Specific examples of the constitutional unit (a1) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0204]

Chemical formula

[0205]

Chemical formula

[0206]

Chemical formula

[0207]

Chemical formula

[0208] [Chemistry]

[0209] [Chemistry]

[0210] [Chemistry]

[0211] [Chemistry]

[0212] [Chemistry]

[0213] Specific examples of the structural unit represented by the above formula (a1-3) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group. Each Rz independently represents a hydrogen atom, an alkyl group, a halogen atom, a halogenated alkyl group, a hydroxy group, or an alkoxy group.

[0214] [Chemistry]

[0215] [Chemistry]

[0216] [Chemistry]

[0217] [Chemistry]

[0218]

Chem.

[0219] The structural unit (a1) is preferably a structural unit represented by the following general formula (a1-0) (hereinafter, also referred to as "structural unit (a1-0)").

[0220]

Chem.

[0221] R and Ar in the formula (a1-0) 0 are the same as R and Ar in the formula (a01) 0 respectively.

[0222] In the formula (a1-0), Y 10 The hydrocarbon group which may have a substituent in is the same as the divalent hydrocarbon group in Va 1 in the formula (a1-1). Y 10 As the divalent linking group in, an aliphatic hydrocarbon group is preferable, a linear or branched alkylene group is more preferable, a linear alkylene group having 1 to 3 carbon atoms is further preferable, and a methylene group or an ethylene group is particularly preferable.

[0223] In the formula (a1-0), m10 is preferably 0 or 1, and more preferably 0.

[0224] In the formula (a1-0), Rx 10Examples of the acid dissociable group in [the compound] include the acid dissociable groups represented by the formula (a1-r-1), (a1-r-2) or (a1-r-4), and the acid dissociable groups represented by the formula (a1-r-2) or (a1-r-4) are more preferred. Rx 10 Examples of the acid dissociable group in [the compound] further preferably include the acid dissociable groups represented by the formula (a1-r2-1), (a1-r2-3), (a1-r2-4) or (a1-r-4).

[0225] As the structural unit (a1-0), the structural unit represented by the following general formula (a1-01) is preferred.

[0226] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R 11 represents a substituent. Y 10 represents a hydrocarbon group which may have a substituent. Rx 10 represents an acid dissociable group. m10 represents an integer of 0 to 2. m11 represents an integer of 0 to 4. When m11 is an integer of 2 or more, two or more R 11 may be the same as or different from each other.]

[0227] R, Y in the formula (a1-01) 10 , Rx 10 , and m10 are the same as R, Y in the formula (a1-0) 10 , Rx 10 , and m10, respectively.

[0228] R in the formula (a1-01) 11 Examples of the substituent in [R] include the same ones as those listed as the substituents of the aromatic hydrocarbon group in Ar in the formula (a01). 0

[0229] In the formula (a1-01), m11 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0230] Specific examples of the structural unit (a1-10) include those exemplified as the specific examples of the structural unit represented by the formula (a1-3). Further, specific examples of the structural unit (a1-0) are shown below, but are not limited thereto. In the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0231] [Chemical formula]

[0232] [Chemical formula]

[0233] The structural unit (a1) contained in the component (A1) may be one kind or two or more kinds. The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol%, more preferably 10 to 75 mol%, still more preferably 30 to 70 mol%, and particularly preferably 40 to 70 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). By setting the proportion of the structural unit (a1) to be not less than the lower limit value of the above-mentioned preferable range, lithography characteristics such as sensitivity, resolution, and CDU improvement are improved. On the other hand, when it is not more than the upper limit value of the above-mentioned preferable range, a balance with other structural units can be achieved, and various lithography characteristics become good.

[0234] The proportion of the structural unit (a1-0) with respect to the total (100 mol%) of all the structural units (a1) is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, and particularly preferably 100 mol%. That is, it is preferable that all of the structural units (a1) are the structural unit (a1-0). By setting the proportion of the structural unit (a1-0) to be not less than the above-mentioned lower limit value with respect to the total (100 mol%) of the structural unit (a1), the sensitivity is more easily increased, and the reduction of roughness is more easily achieved.

[0235] <<Other Structural Units>> (Component (A1)) may have other structural units in addition to the above-described structural unit (a1), if necessary. Examples of other structural units include, for example, a structural unit (a10) represented by the general formula (a10-1) described later; a structural unit (a2) containing a lactone-containing cyclic group; a structural unit (a5) that generates an acid upon exposure; a structural unit (a6) having acid diffusion control properties; a structural unit (a8) derived from a compound represented by the general formula (a8-1) described later, and the like.

[0236] Structural unit (a10): The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

[0237] [Chemical formula] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya x1 is a single bond or a divalent linking group. Wa x1 is an aromatic hydrocarbon group which may have a substituent. n ax1 is an integer of 1 or more.]

[0238] In the formula (a10-1), R is the same as R in the general formula (a1-1). As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of easy availability in industry, a hydrogen atom or a methyl group is particularly preferable.

[0239] In the formula (a10-1), Ya x1 is a single bond or a divalent linking group. In the above chemical formula, the divalent linking group for Ya x1 is not particularly limited, but examples of preferable ones include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like.

[0240] ·A divalent hydrocarbon group which may have a substituent: The divalent hydrocarbon group which may have a substituent may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0241] ··Aliphatic hydrocarbon group The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in its structure.

[0242] ···Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, and specifically includes a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], and the like. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferred. Specifically, alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2- and other alkylalkylene groups can be mentioned. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0243] The linear or branched-chain aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group, etc.

[0244] ··· an aliphatic hydrocarbon group containing a ring in the structure As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which may contain a substituent containing a hetero atom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched-chain aliphatic hydrocarbon group, a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched-chain aliphatic hydrocarbon group, etc. can be mentioned. Examples of the linear or branched-chain aliphatic hydrocarbon group are the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specifically, cyclopentane, cyclohexane and the like can be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and as the polycycloalkane, those having 7 to 12 carbon atoms are preferable, and specifically, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane and the like can be mentioned.

[0245] The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group are more preferable. As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a tert-butoxy group are more preferable, and a methoxy group, an ethoxy group are even more preferable. As the halogen atom as the substituent, a fluorine atom is preferable. Examples of the halogenated alkyl group as the substituent include a group in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom. In the cyclic aliphatic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing a hetero atom, -O-, -C(=O)-O-, -S-, -S(=O)2-, -S(=O)2-O- are preferable.

[0246] ··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 number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and particularly preferably 6 to 12. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Specific examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (for example, biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group) is substituted with an alkylene group (for example, a group obtained by further removing one hydrogen atom from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). 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.

[0247] In the aromatic hydrocarbon group, the hydrogen atoms possessed by the aromatic hydrocarbon group may be 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 the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group is more preferable. Examples of the alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those exemplified as the substituent that substitutes the hydrogen atom of the cyclic aliphatic hydrocarbon group.

[0248] · Divalent linking group containing a heteroatom: Examples of the divalent linking group containing a heteroatom include -O-, -C(=O)-O-, -O-C(=O)-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -NH-C(=NH)- (H may be substituted with a substituent such as an alkyl group or an acyl group), -S-, -S(=O)2-, -S(=O)2-O-, general formula -Y 21 -O-Y 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-O-Y 21 -,-[Y 21 -C(=O)-O] m” -Y 22 -,-Y 21 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 -represented group [wherein Y 21 and Y 22 are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m” is an integer of 0 to 3.], etc. are exemplified. When the divalent linking group containing a heteroatom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, -NH-C(=NH)-, the H thereof may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms. General formula -Y 21 -O-Y 22 -,-Y 21 -O-,-Y21 -C(=O)-O-, -C(=O)-O-Y 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -O-C(=O)-Y 22 - or -Y 21 -S(=O)2-O-Y 22 - Among them, Y 21 and Y 22 are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same ones as described above. Y 21 is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. Y 22 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. In the group represented by the formula -[Y 21 -C(=O)-O] m” -Y 22 -, m” is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, in the formula -[Y 21 -C(=O)-O] m” -Y 22 - As the group represented by, the group represented by the formula -Y 21 -C(=O)-O-Y 22 - is particularly preferred. Among them, the formula -(CH2) a’ -C(=O)-O-(CH2) b’A 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.

[0249] Ya x1 Examples of include a single bond, an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof, with a single bond, an ester bond [-C(=O)-O-, -O-C(=O)-] being more preferred.

[0250] In the formula (a10-1), Wa x1 is an aromatic hydrocarbon group which may have a substituent. Wa x1 Examples of the aromatic hydrocarbon group in include a group obtained by removing (n ax1 +1) hydrogen atoms from an aromatic ring which may have a substituent. The aromatic ring here is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 π electrons. The number of carbon atoms of the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still 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 heterocyclic rings in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring. Also, examples of the aromatic hydrocarbon group in include a group obtained by removing (n x1 +1) hydrogen atoms from an aromatic compound (such as biphenyl or fluorene) containing an aromatic ring which may have two or more substituents. ax1 Among the above, examples of Wa include a group obtained by removing (n x1 from benzene, naphthalene, anthracene or biphenylax1 A group excluding (+1) hydrogen atoms is preferred, and a group excluding (n ax1 +1) hydrogen atoms from benzene or naphthalene is more preferred, and a group excluding (n ax1 +1) hydrogen atoms from benzene is even more preferred.

[0251] Wa x1 The aromatic hydrocarbon group in may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, etc. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent are the same as those listed as the substituent of the cyclic aliphatic hydrocarbon group in Ya x1 The same ones as those listed can be mentioned. The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, even more preferably an ethyl group or a methyl group, and particularly preferably a methyl group. Wa x1 The aromatic hydrocarbon group in is preferably unsubstituted.

[0252] In the formula (a10-1), n ax1 is an integer of 1 or more, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably 1, 2 or 3, and particularly preferably 1 or 2.

[0253] Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[0254]

Chemical formula

[0255]

Chemical formula

[0256] [Chemical]

[0257] (A1) component may have one or more structural units (a10). (A1) component may or may not have the structural unit (a10), but preferably has the structural unit (a10). When the (A1) component has the structural unit (a10), the proportion of the structural unit (a10) in the (A1) component is preferably 20 to 80 mol%, more preferably 25 to 70 mol%, still more preferably 30 to 60 mol%, and particularly preferably 30 to 50 mol% with respect to the total (100 mol%) of all the structural units constituting the (A1) component. By setting the proportion of the structural unit (a10) to be not less than the lower limit value, the sensitivity is more likely to be enhanced. On the other hand, by setting it to be not more than the upper limit value, it is easier to balance with other structural units. Preferably, the (A1) component does not have a structural unit (a10) other than the above structural unit (a01).

[0258] Structural unit (a2): (A1) component may or may not have a structural unit (a2) containing a lactone-containing cyclic group (excluding those corresponding to the structural unit (a1)). The lactone-containing cyclic group of the structural unit (a2) is effective in enhancing the adhesion of the resist film to the substrate when the (A1) component is used for forming the resist film. Further, by having the structural unit (a2), for example, effects such as appropriately adjusting the acid diffusion length, enhancing the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development, etc., the lithography characteristics and the like become good.

[0259] The "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -O-C(=O)- in its ring skeleton. Counting the lactone ring as the first ring, in the case of only the lactone ring, it is a monocyclic group, and in the case of having other ring structures, regardless of the structure, it is called a polycyclic group. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group. As the lactone-containing cyclic group in the structural unit (a2), any group can be used without particular limitation. Specifically, groups represented by the following general formulas (a2-r-1) to (a2-r-7) can be mentioned.

[0260]

Chemical formula

[0261] In the general formulas (a2-r-1) to (a2-r-7), Ra’ 21 as the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable. The alkyl group is preferably linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group, etc. can be mentioned. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable. Ra’ 21 as the alkoxy group, an alkoxy group having 1 to 6 carbon atoms is preferable. The alkoxy group is preferably linear or branched. Specifically, a group in which the alkyl group mentioned as the alkyl group in the above Ra’ 21 is linked to an oxygen atom (-O-) can be mentioned. Ra’ 21 as the halogen atom, a fluorine atom is preferable. Ra’ 21 as the halogenated alkyl group, the alkyl group mentioned as the alkyl group in the above Ra’ 21Examples of the group include those in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

[0262] Ra’ 21 In -COOR” and -OC(=O)R” in, R” is each a hydrogen atom, an alkyl group, or a lactone-containing cyclic group. The alkyl group for R” may be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms. When R” is a linear or branched alkyl group, it preferably has 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 preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a group obtained by removing one or more hydrogen atoms from a monocycloalkane which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as bicycloalkane, tricycloalkane, and tetracycloalkane can be exemplified. More specifically, a group obtained by removing one or more hydrogen atoms from a monocycloalkane such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as tetracyclododecane, etc. can be mentioned. Examples of the lactone-containing cyclic group for R” include the same groups as those represented by the general formulas (a2-r-1) to (a2-r-7) respectively. Ra’ 21 The hydroxyalkyl group in is preferably one having 1 to 6 carbon atoms, and specifically, a group in which at least one of the hydrogen atoms of the alkyl group in the above Ra’ 21 is substituted with a hydroxyl group.

[0263] Ra’ 21 Among them, each is preferably independently a hydrogen atom or a cyano group.

[0264] In the general formulas (a2-r-2), (a2-r-3), and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A” is preferably a linear or branched alkylene group, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropyl group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include groups in which -O- or -S- is interposed at the terminal or between carbon atoms of the alkylene group, and examples thereof include -O-CH2-, -CH2-O-CH2-, -S-CH2-, and -CH2-S-CH2-. A” is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0265] Specific examples of the groups represented by the general formulas (a2-r-1) to (a2-r-7) are given below.

[0266]

Chemical formula

[0267]

Chemical formula

[0268] As the constitutional unit (a2), among others, a constitutional unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent is preferable. Such a constitutional unit (a2) is preferably a constitutional unit represented by the following general formula (a2-1).

[0269]

Chemical formula

[0270] In the formula (a2-1), R is the same as described above. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and from the viewpoint of easy availability in industry, a hydrogen atom or a methyl group is particularly preferable.

[0271] In the formula (a2-1), the divalent linking group in Ya 21 is not particularly limited, but examples thereof preferably include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a heteroatom, and the like. The divalent linking group in Ya 21 is the same as the divalent linking group in Ya x1 in the general formula (a10-1).

[0272] Ya 21 is preferably a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0273] In the formula (a2-1), Ya 21 is a single bond, and La 21 is preferably -COO- or -OCO-.

[0274] In the formula (a2-1), Ra 21 is a lactone-containing cyclic group. Ra 21As the lactone-containing cyclic group in [the compound], the groups represented by the general formulas (a2-r-1) to (a2-r-7) described above are preferably exemplified respectively.

[0275] The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-0) (hereinafter, also referred to as "structural unit (a2-0)").

[0276] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Y 20 represents a single bond or a divalent linking group. Rx 20 represents a lactone-containing cyclic group. ]

[0277] R and Ar in the formula (a2-0) 0 are the same as R and Ar in the formula (a01) 0 respectively.

[0278] In the formula (a2-0), Y 20 Examples of the divalent linking group in [the compound] include the same ones as the divalent linking group in Y 02 in the formula (a02). Examples of the divalent linking group in Y 20 include a group represented by the general formula -Y 21 -O-Y 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -O-C(=O)-Y 22 -, or -Y 21 -S(=O)2-O-Y 22 -[In the formula, Y 21 and Y 22 are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m" is an integer of 1 to 3. ] is preferable, -Y21 -O- or -Y 21 A group represented by -C(=O)-O- is more preferred.

[0279] In the formula (a2-0), Rx 20 As the lactone-containing cyclic group in, the groups represented by the formulas (a2-r-1) to (a2-r-7) are preferred respectively.

[0280] As the structural unit (a2-0), the structural unit represented by the following general formula (a2-01) is preferred.

[0281] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R 21 represents a substituent. Y 20 represents a single bond or a divalent linking group. Rx 20 represents a lactone-containing cyclic group. m21 represents an integer of 0 to 4. When m21 is an integer of 2 or more, two or more R 21 may be the same as or different from each other.]

[0282] R and Y in the formula (a2-01) 20 , and Rx 20 are the same as R, Y 20 , and Rx 20 in the formula (a2-0) respectively.

[0283] R in the formula (a2-01) 21 As the substituent in, the same ones as those exemplified as the substituent of the aromatic hydrocarbon group in Ar 0 in the formula (a01) can be mentioned.

[0284] In the formula (a2-01), m21 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0285] Specific examples of the structural unit (a2-0) are shown below, but are not limited thereto. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[0286]

Chemical formula

[0287] The structural unit (a2) contained in the component (A1) may be one kind or two or more kinds. The component (A1) may or may not have the structural unit (a2). When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 20 mol%, more preferably 1 to 15 mol%, still more preferably 1 to 12 mol%, based on 100 mol% of the total of all the structural units constituting the component (A1). When the proportion of the structural unit (a2) is set to be not less than the preferable lower limit value, the effects of containing the structural unit (a2) can be sufficiently obtained due to the above-described effects. When it is not more than the upper limit value, a balance with other structural units can be achieved, and various lithography characteristics become good.

[0288] The proportion of the structural unit (a2-0) with respect to the total (100 mol%) of all the structural units (a2) is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, even more preferably 90 to 100 mol%, and particularly preferably 100 mol%. That is, it is preferable that all of the structural units (a2) are the structural unit (a2-0). By setting the proportion of the structural unit (a2-0) to be not less than the lower limit value with respect to the total (100 mol%) of the structural units (a2), the sensitivity can be more easily increased and the roughness can be more easily reduced.

[0289] Structural unit (a5): (Component (A1) may or may not have a structural unit (a5) that generates an acid upon exposure. Known structural units can be used for (a5). By having the structural unit (a5), the acid generated upon exposure is more likely to be uniformly distributed within the resist film. Examples of the structural unit (a5) include structural units containing the structures described in component (B) below. For example, structural units containing the structures represented by any of the general formulas (b-1) to (b-3) described below can be mentioned.) Examples of the structural unit (a5) preferably include a structural unit represented by the following general formula (a5-1).

[0290] [Chemical formula] [In the formula, R m is an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La 50 is a divalent linking group or a single bond. Ra 50 is an optionally substituted divalent hydrocarbon group. n a5 is an integer from 0 to 2. La 51 is a divalent linking group. Ya 5 is a divalent linking group that may have a hetero atom, or a single bond. Ra 51 and Ra 52 are each 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+ is an m-valent onium cation.]

[0291] {Anion part} In the formula (a5-1), R m is an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. R mThe alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. can be mentioned. The alkyl halide group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, iodine atom, etc. Among the halogen atoms in the alkyl halide group, a fluorine atom is particularly preferable. R m 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 from the viewpoint of easy availability in industry, a hydrogen atom or a methyl group is most preferable.

[0292] In the formula (a5-1), La 50 is a divalent linking group or a single bond. La 50 The divalent linking group in La is not particularly limited, but examples thereof preferably include a divalent hydrocarbon group which may have a substituent and a divalent linking group containing a hetero atom, and are the same as the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom exemplified as the divalent linking group in Ya x1 above. Among the above, La 50 is preferably an ester bond [-C(=O)-O-, -O-C(=O)-], an ether bond (-O-), a linear or branched alkylene group, an aromatic hydrocarbon group or a combination thereof, or a single bond. Among these, La 5 is more preferably an ester bond [-C(=O)-O-, -O-C(=O)-] or a single bond, and even more preferably an ester bond [-C(=O)-O-, -O-C(=O)-].

[0293] In the formula (a5-1), Ra 50is a divalent hydrocarbon group which may have a substituent. Ra 50 The divalent hydrocarbon group in 50 may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0294] ··Ra 50 The aliphatic hydrocarbon group in 50 The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure.

[0295] ···linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, and specifically includes a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], and the like. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferred. Specifically, alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2- and other alkylalkylene groups can be mentioned. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0296] The above-mentioned linear or branched-chain aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group, and the like.

[0297] ···an aliphatic hydrocarbon group containing a ring in the structure As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which may contain a substituent containing a hetero atom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched-chain aliphatic hydrocarbon group, a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched-chain aliphatic hydrocarbon group, and the like can be mentioned. As the above-mentioned linear or branched-chain aliphatic hydrocarbon group, the same ones as those described above can be mentioned. 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. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specifically, cyclopentane, cyclohexane and the like can be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and as the polycycloalkane, those having 7 to 12 carbon atoms are preferable, and specifically, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane and the like can be mentioned.

[0298] The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable. As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, 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 preferable, and a methoxy group and an ethoxy group are most preferable. Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable. Examples of the halogenated alkyl group as the substituent include a group in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom. In the cyclic aliphatic hydrocarbon group, a part of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing a hetero atom, -O-, -C(=O)-O-, -S-, -S(=O)2-, -S(=O)2-O- are preferable.

[0299] ··Ra 50Aromatic hydrocarbon group in 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 number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and particularly preferably 6 to 12. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. Specifically, as the aromatic ring, aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocyclic rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a heteroatom, and the like can be mentioned. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. Specifically, as the aromatic heterocyclic ring, a pyridine ring, a thiophene ring, and the like can be mentioned. Specific examples of the aromatic hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group); a group obtained by removing two hydrogen atoms from an aromatic compound containing two or more aromatic rings (for example, biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (aryl group or heteroaryl group) is substituted with an alkylene group (for example, a group obtained by further removing one hydrogen atom from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group), and the like. The number of carbon atoms of 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.

[0300] In the aromatic hydrocarbon group, the hydrogen atoms possessed by the aromatic hydrocarbon group may be 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 the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and the like. As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are most preferable. Examples of the alkoxy group, halogen atom, and halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

[0301] In the formula (a5-1), n a5 is an integer of 0 to 2. Among the above, Ra 50 is preferably an aliphatic hydrocarbon group containing a ring in the structure, more preferably a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure, and still more preferably an alicyclic hydrocarbon group which may have a substituent and is a polycyclic group or a monocyclic group. Alternatively, among the above, Ra 50 is preferably an aromatic hydrocarbon group.

[0302] n a5 When it is 2, the two Ra 50 may both be alicyclic hydrocarbon groups which may have a substituent, may both be aromatic hydrocarbon groups, or may be a combination of an alicyclic hydrocarbon group which may have a substituent and an aromatic hydrocarbon group.

[0303] In the formula (a5-1), La 51 is a divalent linking group. La 51 Examples of the divalent linking group in La include non-hydrocarbon-based oxygen atom-containing linking groups such as an oxygen atom (ether bond: -O-), an ester bond (-C(=O)-O-), an oxycarbonyl group (-O-C(=O)-), an amide bond (-C(=O)-NH-), a carbonyl group (-C(=O)-), and a carbonate bond (-O-C(=O)-O-); combinations of the non-hydrocarbon-based oxygen atom-containing linking group and an alkylene group, etc. A sulfonyl group (-SO2-) may be further linked to this combination. Examples of such a divalent linking group include the linking groups represented by the general formulas (L-al-1) to (L-al-8) respectively. In the general formulas (L-al-1) to (L-al-8), Ra in the above formula (a5-1) 50 is bonded to V' in the general formulas (L-al-1) to (L-al-8). 101

[0304] La 51 is preferably 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).

[0305] In the above formula (a5-1), Ya 5 is a divalent linking group which may have a hetero atom or a single bond. Ya 5 The divalent linking group in is not particularly limited, and preferably includes a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, etc. Ya 5 For the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom in, it is the same as the divalent linking group exemplified as the divalent linking group in the above Ya x1 Among the above, Ya 5 is preferably a linear or branched alkylene group or a single bond, and more preferably a single bond.

[0306] In the above formula (a5-1), Ra 51 and Ra 52 are each independently a hydrogen atom, a fluorine atom or a fluorinated alkyl group. Ra 51 and Ra 52 ​​As the fluorinated alkyl group in the formula, a linear or branched fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a trifluoromethyl group is more preferable. In the formula (a5-1), SO3 - Ra bonded to the carbon atom adjacent to 51 and Ra 52 At least one of them is preferably a fluorine atom from the viewpoint of acid strength.

[0307] In the formula (a5-1), n5 is an integer of 1 to 4, and 1, 2 or 3 is preferable.

[0308] {Cation part} In the formula (a5-1), M’ m+ represents an m-valent onium cation. Among these, M’ m+ is preferably a sulfonium cation or an iodonium cation. m is an integer of 1 or more.

[0309] Preferred cation parts ((M’ m+ )) 1 / m ) include organic cations represented by the general formulas (ca-1) to (ca-3), respectively.

[0310] The cation part ((M’ m+ )) 1 / m ) in the formula (a5-1) is preferably a sulfonium cation, more preferably a cation represented by the general formulas (ca-1) to (ca-3), still more preferably a cation represented by the formula (ca-1), and particularly preferably a cation represented by the formulas (ca-1-1) to (ca-1-84).

[0311] Preferred specific examples of the constitutional unit (a5) are shown below. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group. m and M’ m+ are the same as m and M’ m+ in the above general formula (a5-1).

[0312] [Chemical]

[0313] [Chemical]

[0314] [Chemical]

[0315] The structural unit (a5) contained in the component (A1) may be one type or two or more types. When the component (A1) has the structural unit (a5), the proportion of the structural unit (a5) in the component (A1) is preferably 5 to 25 mol%, more preferably 10 to 20 mol%, and still more preferably 15 to 20 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). When the proportion of the structural unit (a5) is at least the lower limit of the above-mentioned preferred range, it becomes easier to achieve further increased sensitivity and improved resolution. On the other hand, when it is at most the upper limit of the above-mentioned preferred range, it becomes easier to balance with other structural units. Preferably, the component (A1) does not have a structural unit (a5) other than the above structural unit (a02).

[0316] Structural unit (a6): The structural unit (a6) is a structural unit having acid diffusion controllability. The component (A1) may or may not have the structural unit (a6). Known structural units can be used as the structural unit (a6). Examples of the structural unit (a6) include structural units containing the structures described in the following components (D1) and (D2). For example, structural units containing a structure represented by any of the following general formulas (d1-1) to (d1-3) can be mentioned.

[0317] As the structural unit (a6), a structural unit represented by the following general formula (a6-0) (hereinafter, also referred to as "structural unit (a6-0)") is preferable.

[0318] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Y 60 represents a divalent linking group. m is an integer of 1 or more, and M m+ is an m-valent cation.]

[0319] {Anion part} R and Ar in the formula (a6-0) 0 are the same as R and Ar in the formula (a01) 0 respectively.

[0320] In the formula (a6-0), Y 60 as the divalent linking group in is the same as the divalent linking group in Y 02 in the formula (a02). Y 60 as the divalent linking group in preferably has a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group which may have a substituent include a cyclic group which may have a substituent, a linear alkylene group which may have a substituent, or a linear alkenylene group which may have a substituent. Among these, a hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a linear alkylene group which may have a substituent is preferable.

[0321] Examples of the aromatic hydrocarbon group preferably include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure composed of a bicyclooctane skeleton and another ring structure). Examples of the aliphatic cyclic group include a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, and tetracyclododecane is more preferable. As the chain-like alkylene group, those having 1 to 10 carbon atoms are preferred, and it may be a linear alkylene group or a branched alkylene group.

[0322] Y 60 Examples of the substituent that the hydrocarbon group in may optionally have include a hydroxy group, an oxo group, an alkyl group, an aryl group, a halogen atom, a fluorinated alkyl group, a lactone-containing cyclic group represented by each of the formulas (a2-r-1) to (a2-r-8), an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is included as a substituent, it may be via an alkylene group, and in this case, as the substituent, a linking group represented by each of the above formulas (L-al-1) to (L-al-5) is preferred. Incidentally, Y 60 When the hydrocarbon group in has, as a substituent, a linking group represented by each of the formulas (L-al-1) to (L-al-7), in the formulas (L-al-1) to (L-al-7), Y 60 is bonded to the carbon atom constituting the hydrocarbon group in Y 101 through V' in the above formulas (L-al-1) to (L-al-7).

[0323] Y 60 is preferably one of those exemplified as the cyclic group that may have a substituent in Ra in the formula (a02-1), and more preferably an aromatic hydrocarbon group that may have a substituent. The aromatic hydrocarbon group in Y 021 preferably has an iodine atom as a substituent. Examples of the number of iodine atoms as a substituent include 1 to 3, and 1 or 2 is preferred. 60 As the constitutional unit (a6-0), a constitutional unit represented by the following general formula (a6-01) is preferred.

[0324]

Chemical formula

[0325]

Chemical formula

[0326] R and Y in the formula (a6-01) 60 are the same as R and Y in the formula (a6-0) 60 respectively.

[0327] R in the formula (a6-01) 61 Examples of the substituents in include the same ones as those exemplified as the substituents of the aromatic hydrocarbon group in Ar in the formula (a01) 0 .

[0328] In the formula (a6-01), m61 is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0329] {Cation part} In the formula (a6-0), M m+ represents an m-valent onium cation. Among these, M m+ is preferably a sulfonium cation or an iodonium cation. m is an integer of 1 or more.

[0330] Preferred cation parts ((M m+ )) 1 / m include organic cations respectively represented by the general formulas (ca-1) to (ca-3).

[0331] The cation part ((M m+ )) in the formula (a6-0) 1 / mAs for this, a sulfonium cation is preferable, a cation represented by each of the formulas (ca-1) to (ca-3) is more preferable, a cation represented by the formula (ca-1) is still more preferable, and a cation represented by each of the formulas (ca-1-1) to (ca-1-84) is particularly preferable.

[0332] Specific examples of the structural unit (a6-0) are shown below, but are not limited thereto. In the following formulas, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group. m and M m+ are the same as m and M m+ in the above general formula (a6-0).

[0333]

Chemical formula

[0334] The structural unit (a6) contained in the component (A1) may be one kind or two or more kinds. When the component (A1) has the structural unit (a6), the proportion of the structural unit (a6) in the component (A1) is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, still more preferably 3 to 10 mol% with respect to the total (100 mol%) of all the structural units constituting the component (A1). When the proportion of the structural unit (a6) is at or above the lower limit value of the above-mentioned preferable range, it becomes easier to achieve further higher sensitivity. On the other hand, when it is at or below the upper limit value of the above-mentioned preferable range, it becomes easier to balance with other structural units.

[0335] The ratio of the constitutional unit (a6-0) to the total (100 mol%) of all constitutional units (a6) is preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%, even more preferably 90 to 100 mol%, and particularly preferably 100 mol%. That is, it is preferable that all of the constitutional units (a6) are the constitutional unit (a6-0). By setting the ratio of the constitutional unit (a6-0) to be equal to or higher than the lower limit value with respect to the total (100 mol%) of the constitutional units (a6), the sensitivity is more easily increased and the roughness is more easily reduced.

[0336] Constitutional unit (a8): The constitutional unit (a8) is a constitutional unit derived from a compound represented by the following general formula (a8-1). The component (A1) may or may not have the constitutional unit (a8).

[0337] [Chemical formula] [In the formula, W 2 is a polymerizable group-containing group. Ya x2 is a single bond or an (n ax2 +1)-valent linking group. Ya x2 and W 2 may form a condensed ring. R 1 is a fluorinated alkyl group having 1 to 12 carbon atoms. R 2 is an organic group having 1 to 12 carbon atoms which may have a fluorine atom or a hydrogen atom. R 2 and Ya x2 may be bonded to each other to form a ring structure. n ax2 is an integer of 1 to 3. ]

[0338] W 2 In the polymerizable group-containing group of W, the "polymerizable group" is a group that enables a compound having a 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.

[0339] As the group containing a polymerizable group, it may be a group composed only of polymerizable groups, or a group composed of a polymerizable group and other groups other than the polymerizable group. Examples of the other groups other than the polymerizable group include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a heteroatom, and the like. Examples of the group containing a polymerizable group include, for example, a group represented by the chemical formula: C(R X11 )(R X12 )=C(R X13 )-Ya x0 -. 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.

[0340] Examples of the condensed ring formed by Ya x2 and W 2 include a condensed ring formed by the polymerizable group at the W 2 site and Ya x2 , and a condensed ring formed by a group other than the polymerizable group at the W 2 site and Ya x2 . The condensed ring formed by Ya x2 and W 2 may have a substituent.

[0341] Specific examples of the structural unit (a8) are shown below. In the following formula, R α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[0342]

Chemical formula

[0343] Among the above examples, the structural unit (a8) is preferably at least one selected from the group consisting of structural units represented by 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 structural units represented by chemical formulas (a8-1-01) to (a8-1-04), (a8-1-09).

[0344] (A1) component may have one or more than two structural units (a8). (A1) component may or may not have the structural unit (a8). The proportion of the structural unit (a8) in the (A1) component is preferably 0 to 50 mol%, more preferably 0 to 30 mol%, based on the total (100 mol%) of all the structural units constituting the (A1) component.

[0345] The (A1) component contained in the resist composition may be used alone or in combination of two or more.

[0346] (A1) component, among all the structural units constituting the (A1) component, it is preferable that the proportion of the structural unit represented by the following general formula (a0-z) (hereinafter, also referred to as "structural unit (a0-z)") is larger.

[0347] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar 0 represents an aromatic hydrocarbon group which may have a substituent. Rz 0 represents an organic group.]

[0348] R and Ar in the formula (a0-z) 0 are the same as R and Ar in the formula (a01) 0 respectively.

[0349] Rz in the formula (a0-z) 0The organic group in it is not particularly limited. Rz 0 Examples thereof include a group containing a hydroxyaromatic ring, a group containing a sulfonate, a group containing an acid dissociable group, a group containing a lactone-containing cyclic group, a group containing a carboxylate, and the like.

[0350] As the constituent unit (a0-z), the constituent unit represented by the following general formula (a0-z1) is preferable.

[0351] [Chemical formula] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Rz 0 represents an organic group. Rz 1 represents a substituent. mz1 represents an integer of 0 to 4. When mz1 is an integer of 2 or more, two or more Rz 1 may be the same as or different from each other.]

[0352] R and Rz in the formula (a0-z1) 0 are the same as R and Rz 0 in the formula (a0-z), respectively.

[0353] Rz in the formula (a0-z1) 1 Examples of the substituent in it are the same as those exemplified as the substituent of the aromatic hydrocarbon group in Ar 0 in the formula (a01).

[0354] In the formula (a0-z1), mz1 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

[0355] The component (A1) has at least the constitutional unit (a01) and the constitutional unit (a02) as the constitutional units (a0-z). The component (A1) preferably has one or more selected from the group consisting of the constitutional unit (a1-0), the constitutional unit (a2-0), and the constitutional unit (a6-0) as the constitutional units (a0-z). The component (A1) preferably has the constitutional unit (a01), the constitutional unit (a02), and the constitutional unit (a1-0) as the constitutional units (a0-z), and more preferably has the constitutional unit (a6-0). The component (A1) may further have the constitutional unit (a2-0) as the constitutional units (a0-z).

[0356] The plurality of types of constitutional units (a0-z) possessed by the component (A1) are Ar in the formula (a0-z). 0 It is preferable that the structures are the same structure. For example, it is preferable that all of the plurality of types of constitutional units (a0-z) possessed by the component (A1) are constitutional units represented by the formula (a0-z1).

[0357] The number of types of the constitutional units (a0-z) possessed by the component (A1) is preferably 50% or more, more preferably 60% or more, still more preferably 70% or more, still more preferably 80% or more, still more preferably 90% or more, and particularly preferably 100% with respect to the total number of types (100%) of the constitutional units possessed by the component (A1). For example, when the component (A1) has X types of constitutional units and Y types of them are constitutional units corresponding to the constitutional units (a0-z), Y / X is preferably 0.5 or more, more preferably 0.6 or more, still more preferably 0.7 or more, still more preferably 0.8 or more, still more preferably 0.9 or more, and particularly preferably 1. When the ratio of the number of types of the constitutional units (a0-z) to the total number of types (100%) of the constitutional units possessed by the component (A1) is equal to or higher than the above lower limit value, roughness is more likely to be reduced. This is presumably because the participation rates of various monomers during polymerization become uniform and the distribution of various constitutional units is likely to become uniform.

[0358] The constituent units (a0-z) in the (A1) component are preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more, still more preferably 80 mol% or more, still more preferably 90 mol% or more, and particularly preferably 100 mol% with respect to the total (100 mol%) of all the constituent units constituting the (A1) component. That is, it is preferable that all the constituent units constituting the (A1) component are the constituent units (a0-z).

[0359] In the resist composition of the present embodiment, among all the solid components contained in the resist composition, as the constituent units (a0-z), it is preferable that the ratio of the components incorporated in the (A1) component is large. For example, with respect to the total (100 mol%) of all the solid components, the ratio of the components incorporated in the (A1) component as the constituent units (a0-z) is preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more, still more preferably 80 mol% or more, still more preferably 90 mol% or more, and particularly preferably 100 mol%. By setting the ratio of the components incorporated in the (A1) component as the constituent units (a0-z) to be equal to or higher than the above lower limit value with respect to the total (100 mol%) of all the solid components, the roughness can be further reduced. This is presumably because the distribution of each component in the resist composition tends to be uniform. Note that the solid components are components other than the organic solvent component ((S) component) in the resist composition. Examples of the solid components include the (A) component, the (B) component described later, and the (D) component described later.

[0360] Examples of the component (A1) include a polymer compound having structural units (a01), (a02), and (a1); a polymer compound having structural units (a01), (a02), (a1), and (a2); a polymer compound having structural units (a01), (a02), (a1), (a2), and (a6); a polymer compound having structural units (a01), (a02), (a1), and (a6); a polymer compound having structural units (a01), (a02), (a1), and (a10); a polymer compound having structural units (a01), (a02), (a1), (a2), and (a10); and the like. The structural units (a1), (a2), and (a6) are preferably structural units (a1-0), (a2-0), and (a6-0), respectively. Among these, examples of the component (A1) preferably include a polymer compound composed of structural units (a01), (a02), and (a1-0); a polymer compound composed of structural units (a01), (a02), (a1-0), and (a2-0); a polymer compound composed of structural units (a01), (a02), (a1-0), and (a6-0); and a polymer compound composed of structural units (a01), (a02), (a1-0), (a2-0), and (a6-0).

[0361] Such a component (A1) can be produced by dissolving monomers that induce each structural unit in a polymerization solvent, and adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (e.g., V-601, etc.) thereto and performing polymerization. Alternatively, such component (A1) can be produced by dissolving each monomer that induces constitutional unit (a01) and constitutional unit (a02), and each monomer that induces an arbitrary constitutional unit (for example, constitutional unit (a1), constitutional unit (a2), constitutional unit (a6), etc.) in a polymerization solvent, adding a radical polymerization initiator as described above thereto, performing polymerization, and then performing a deprotection reaction. In addition, during polymerization, for example, 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. Thus, a copolymer into which a hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms is introduced is effective in reducing development defects and LER (Line Edge Roughness: non-uniform unevenness on the sidewall of the line).

[0362] The weight average molecular weight (Mw) of component (A1) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, and is preferably 1000 to 50000, more preferably 5000 to 40000, and even more preferably 5000 to 30000. When the Mw of component (A1) is below the preferable upper limit of this range, there is sufficient solubility in a resist solvent for use as a resist, and when it is above the preferable lower limit of this range, the dry etching resistance and the cross-sectional shape of the resist pattern are good. The dispersity (Mw / Mn) of component (A1) is not particularly limited, and is preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and particularly preferably 1.0 to 2.0. Note that Mn represents the number average molecular weight.

[0363] ·Regarding component (A2) The resist composition of this embodiment may also use, as component (A), a base material component whose solubility in a developer changes by the action of an acid and which does not correspond to the above-mentioned component (A1) (hereinafter referred to as "component (A2)"). Component (A2) is not particularly limited, and may be arbitrarily selected and used from a number of those conventionally known as base material components for chemically amplified resist compositions. (Component (A2)) may be used alone or in combination of two or more of a high molecular compound or a low molecular compound.

[0364] The proportion of component (A1) in component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, still more preferably 75% by mass or more, and particularly preferably 100% by mass based on the total mass of component (A). When the proportion is at least the above lower limit value, a resist pattern excellent in various lithography characteristics such as high sensitivity, resolution, and roughness improvement is likely to be formed.

[0365] In the resist composition of the present embodiment, the content of component (A) may be adjusted according to the resist film thickness to be formed and the like.

[0366] <Acid generator component (B)> The resist composition of the present embodiment may contain an acid generator component (B) that generates an acid upon exposure. Component (B) is not particularly limited, and those proposed as acid generators 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, oxime sulfonate-based acid generators; diazomethane-based acid generators such as bisalkyl or bisaryl sulfonyldiazomethanes and poly(bissulfonyl)diazomethanes; nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators. The form of containing component (B) may be in the form of a compound, may be incorporated into component (A1) as the above structural unit (a5), or may be in both of these forms.

[0367] Examples of the onium salt-based acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as "(b-1) component"), a compound represented by the general formula (b-2) (hereinafter also referred to as "(b-2) component"), or a compound represented by the general formula (b-3) (hereinafter also referred to as "(b-3) component").

[0368] Examples of the onium salt-based acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as "(b-1) component"), a compound represented by general formula (b-2) (hereinafter also referred to as "(b-2) component"), or a compound represented by general formula (b-3) (hereinafter also referred to as "(b-3) component").

[0369] [Chemical formula] [In the formula, R 101 and R 104 ~R 108 are each independently a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. R 104 and R 105 may be mutually bonded to form a ring structure. R 102 is a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. Y 101 is a divalent linking group containing an oxygen atom or a single bond. V 101 ~V 103 are each independently a single bond, an alkylene group or a fluorinated alkylene group. However, Y 101 and V 101 do not simultaneously become a single bond. L 101 ~L 102 are each independently a single bond or an oxygen atom. L 103 ~L 105 are each independently a single bond, -CO- or -SO2-. m is an integer of 1 or more, and M’ m+ is an m-valent onium cation.]

[0370] {Anion part} ·Anion in the (b-1) component In formula (b-1), R 101 is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.

[0371] Cyclic group which may have a substituent: The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. Further, the aliphatic hydrocarbon group is preferably saturated.

[0372] R 101 The aromatic hydrocarbon group in R is a hydrocarbon group having an aromatic ring. The number of carbon atoms of the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, still more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. R 101 Specific examples of the aromatic ring of the aromatic hydrocarbon group in R include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic ring in which a part of the carbon atoms constituting these aromatic rings is substituted with a hetero atom. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom. R 101 Specific examples of the aromatic hydrocarbon group in R include a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), and a group in which one hydrogen atom of the aromatic ring is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl group, etc.). The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0373] R 101 The cyclic aliphatic hydrocarbon group in R includes an aliphatic hydrocarbon group containing a ring in the structure. Examples of the aliphatic hydrocarbon group containing a ring in this structure include an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group 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, more preferably 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically, cyclopentane, cyclohexane, etc. may be mentioned. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, as the polycycloalkane, polycycloalkanes having a crosslinked ring system polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, and polycycloalkanes having a condensed ring system polycyclic skeleton such as a cyclic group having a steroid skeleton are more preferable.

[0374] Among them, R 101 The cyclic aliphatic hydrocarbon group in is preferably a group obtained by removing one or more hydrogen atoms from monocycloalkane or polycycloalkane, more preferably a group obtained by removing one hydrogen atom from polycycloalkane, even more preferably an adamantyl group or a norbornyl group, and particularly preferably an adamantyl group.

[0375] The linear aliphatic hydrocarbon group that 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 most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, methylene group [-CH2-], ethylene group [-(CH2)2-], trimethylene group [-(CH2)3-], tetramethylene group [-(CH2)4-], pentamethylene group [-(CH2)5-], etc. may be mentioned. The branched aliphatic hydrocarbon group, which may be bonded to an alicyclic hydrocarbon group, preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred. Specifically, alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-; alkyltrimethylene groups such as -CH(CH3)CH2CH2-, -CH2CH(CH3)CH2-; alkyltetramethylene groups such as -CH(CH3)CH2CH2CH2-, -CH2CH(CH3)CH2CH2- and other alkylalkylene groups can be mentioned. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0376] Also, R 101 The cyclic hydrocarbon group in may contain a hetero atom such as a heterocyclic ring. Specifically, 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) can be mentioned.

[0377] R 101 Examples of the substituent in the cyclic group of include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group and the like. As the alkyl group as a substituent, an alkyl group having 1 to 5 carbon atoms is preferred. As the alkoxy group as a substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a tert-butoxy group are more preferable, and a methoxy group and an ethoxy group are most preferable. As the halogen atom as a substituent, a fluorine atom, a bromine atom, and an iodine atom are preferable. As the halogenated alkyl group as a substituent, a group in which a part or all of hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, etc., are substituted with the halogen atom can be mentioned. The carbonyl group as a substituent is a group that substitutes the methylene group (-CH2-) constituting the cyclic hydrocarbon group.

[0378] R 101 The cyclic hydrocarbon group in may be a condensed ring type group containing a condensed ring in which an aliphatic hydrocarbon ring and an aromatic ring are condensed. Examples of the condensed ring include those in which one or more aromatic rings are condensed to a polycycloalkane having a bridged ring system polycyclic skeleton. Specific examples of the bridged ring system polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. As the condensed ring type, a group containing a condensed ring in which two or three aromatic rings are condensed to a bicycloalkane is preferable, and a group containing a condensed ring in which two or three aromatic rings are condensed to bicyclo[2.2.2]octane is more preferable. R 101 Specific examples of the condensed ring type group in include those represented by the following formulas (r-br-1) to (r-br-2). In the formula, * represents a bond that binds to Y in the formula (b-1). 101 represents the bond that binds to.

[0379]

Chemical formula

[0380] R 101Examples of the substituent that the condensed cyclic group in [[ ]] may optionally have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an aromatic hydrocarbon group, an alicyclic hydrocarbon group, and the like. Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the condensed cyclic group are the same as those exemplified as the substituent of the cyclic group in the above R 101 Examples of the aromatic hydrocarbon group as the substituent of the condensed cyclic group include a group obtained by removing one hydrogen atom from an aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring is substituted with an alkylene group (for example, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc., arylalkyl groups), and heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-6), respectively. Examples of the alicyclic hydrocarbon group as the substituent of the condensed cyclic group include a group obtained by removing one hydrogen atom from a monocycloalkane such as cyclopentane or cyclohexane; a group obtained by removing one hydrogen atom from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane or tetracyclododecane; lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), respectively; -SO2-containing cyclic groups represented by the general formulas (b5-r-1) to (b5-r-4), respectively; and heterocyclic groups represented by the formulas (r-hr-7) to (r-hr-16), respectively.

[0381] Optionally substituted chain alkyl group: R 101 The chain alkyl group of [[ ]] 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-chain 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, for example, 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, 4-methylpentyl group, etc. may be mentioned.

[0382] Optionally substituted chain alkenyl group: R 101 The chain alkenyl group of may be linear or branched, preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, still more preferably 2 to 4 carbon atoms, and particularly preferably 3 carbon atoms. Examples of the linear alkenyl group include vinyl group, propenyl group (allyl group), butenyl group, etc. Examples of the branched-chain alkenyl group include 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group, etc. Among the above, the linear alkenyl group is preferred as the chain alkenyl group, and the vinyl group and propenyl group are more preferred, and the vinyl group is particularly preferred.

[0383] R 101 Examples of the substituent in the chain alkyl group or alkenyl group of include alkoxy group, halogen atom, halogenated alkyl group, hydroxyl group, carbonyl group, nitro group, amino group, cyclic group in the above R 101 etc.

[0384] In formula (b-1), Y 101 is a single bond or a divalent linking group containing an oxygen atom. Y 101 When is a divalent linking group containing an oxygen atom, the Y 101 may contain atoms other than the oxygen atom. Examples of the atoms other than the oxygen atom include carbon atom, hydrogen atom, sulfur atom, nitrogen atom, etc. Examples of the divalent linking group containing an oxygen atom include the linking groups represented by the above general formulas (L-al-1) to (L-al-8), respectively. In the following general formulas (L-al-1) to (L-al-8), R in the above formula (b-1) 101 is bonded to V' in the following general formulas (L-al-1) to (L-al-8). 101 That is.

[0385] In the formula (b-1), V 101 is a single bond, an alkylene group or a fluorinated alkylene group. Among them, V 101 is preferably a single bond or a linear fluorinated alkylene group having 1 to 4 carbon atoms.

[0386] In the formula (b-1), R 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R 102 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0387] Specific examples of the anion part represented by the formula (b-1) include, for example, when Y 101 is a single bond, fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anion and perfluorobutanesulfonate anion; when Y 101 is a divalent linking group containing an oxygen atom, anions represented by any of the following formulas (an-1) to (an-3).

[0388] [In the formula, R'' [wherein, R'' 101 is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by the above chemical formulas (r-hr-1) to (r-hr-6), a condensed cyclic group represented by the formula (r-br-1) or (r-br-2), a chain alkyl group which may have a substituent or an aromatic cyclic group which may have a substituent. R'' 102is an aliphatic cyclic group which may have a substituent, a condensed cyclic group represented by the formula (r-br-1) or (r-br-2), a lactone-containing cyclic group represented by the general formula (a2-r-1), (a2-r-3) to (a2-r-7), or a -SO2-containing cyclic group represented by the general formula (b5-r-1) to (b5-r-4). R” 103 is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent. V” 101 is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. v” are each independently an integer of 0 to 3, q” are each independently an integer of 0 to 20, and n” is 0 or 1.]

[0389] R” 101 , R” 102 and R” 103 The aliphatic cyclic group which may have a substituent of R”, R” and R” is preferably a group exemplified as the cyclic aliphatic hydrocarbon group in R in the formula (b-1). Examples of the substituent include the same substituents as those which may substitute the cyclic aliphatic hydrocarbon group in R in the formula (b-1). 101 in the formula (b-1). 101 in the formula (b-1).

[0390] R” 101 and R” 103 The aromatic cyclic group which may have a substituent of R” and R” is preferably a group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in R in the formula (b-1). Examples of the substituent include the same substituents as those which may substitute the aromatic hydrocarbon group in R in the formula (b-1). 101 in the formula (b-1). 101 in the formula (b-1).

[0391] R” 101 The chain alkyl group which may have a substituent in is preferably a group exemplified as the chain alkyl group in R in the formula (b-1). 101 in the formula (b-1). R” 103 The chain alkenyl group which may have a substituent in 103 is preferably a group exemplified as the chain alkenyl group in R in the formula (b-1). 101

[0392] · Anion in the component (b-2) In the formula (b-2), R 104 , R 105 are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each is the same as R in the formula (b-1). 101 However, R 104 , R 105 may be bonded to each other to form a ring. R 104 , R 105 is preferably a chain alkyl group which may have a substituent, more preferably a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. The number of carbon atoms of the chain alkyl group is preferably 1 to 10, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. For the chain alkyl groups of R 104 , R 105 , the smaller the number of carbon atoms within the above range, the better the solubility in the resist solvent and other reasons. Also, in the chain alkyl groups of R 104 , R 105 , the more hydrogen atoms are substituted with fluorine atoms, the stronger the acid strength, and the better the transparency to high-energy light or electron beams of 250 nm or less. The ratio of fluorine atoms in the chain alkyl group, that is, the fluorination rate, is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms. In the formula (b-2), V 102 , V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each is the same as V in the formula (b-1).​101 The same ones can be cited. In formula (b-2), L 101 , L 102 are each independently a single bond or an oxygen atom.

[0393] · Anion in the (b-3) component In formula (b-3), R 106 ~R 108 are each independently a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and each is the same as R in formula (b-1) 101 The same ones can be cited. In formula (b-3), L 103 ~L 105 are each independently a single bond, -CO- or -SO2-.

[0394] Among the above, as the anion part of the (B) component, the anion in the (b-1) component is preferable, and the anion represented by the above formula (an-1) is more preferable.

[0395] {Cation part} In the above formulas (b-1), (b-2), and (b-3), M' m+ represents an m-valent onium cation. Among these, a sulfonium cation and an iodonium cation are preferable. m is an integer of 1 or more.

[0396] As the cation part of the (B) component, a sulfonium cation is preferable, the cations respectively represented by the above formulas (ca-1) to (ca-3) are more preferable, the cation represented by the above formula (ca-1) is still more preferable, and the cations respectively represented by the above formulas (ca-1-1) to (ca-1-84) are particularly preferable.

[0397] In the resist composition of this embodiment, the (B) component may be used alone or in combination of two or more. When the resist composition contains the component (B), in the resist composition, the content of the component (B) is preferably less than 50 parts by mass, more preferably 5 to 45 parts by mass, and even more preferably 10 to 43 parts by mass with respect to 100 parts by mass of the component (A). By setting the content of the component (B) within the above-mentioned preferred range, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, and the storage stability as a resist composition is good, which is preferable.

[0398] In the resist composition of the present embodiment, the acid generator component is incorporated into the component (A1) as the structural unit (a02). Therefore, it is preferable that the resist composition of the present embodiment does not contain the component (B).

[0399] <Base component (D)> The resist composition of the present embodiment may contain a base component ((D) component) that traps (i.e., controls the diffusion of) the acid generated by exposure, in addition to the component (A). The component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure in the resist composition. Examples of the component (D) include a photo-dissociable base (D1) that decomposes upon exposure and loses acid diffusion controllability (hereinafter referred to as the "(D1) component"), a nitrogen-containing organic compound (D2) that does not correspond to the (D1) component (hereinafter referred to as the "(D2) component"), and the like. Among these, the photo-dissociable base ((D1) component) is preferable because it is easy to enhance the characteristics of high sensitivity, reduction of roughness, and suppression of the occurrence of coating defects. The forms of containing the (D1) component and the (D2) component may be in the form of a compound, may be in the form incorporated into the component (A1) as the above-mentioned structural unit (a6), or may be in both of these forms. The compound exemplified as the (D1) component below may be used as the acid generator component ((B) component) described below in combination with other compounds in some cases.

[0400] ·Regarding the (D1) component (D1) The component is not particularly limited as long as it decomposes upon exposure and loses its acid diffusion controllability. One or more compounds selected from the group consisting of a compound represented by the following general formula (d1-1) (hereinafter referred to as "(d1-1) component"), a compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component"), and a compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-3) component") are preferred. In the exposed portion of the resist film, the (d1-1) to (d1-3) components decompose and lose their acid diffusion controllability (basicity), so they do not act as quenchers. In the unexposed portion of the resist film, they act as quenchers.

[0401] [Chemical formula] [In the formula, Rd 1 ~Rd 4 is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. However, it is assumed that no fluorine atom is bonded to the carbon atom adjacent to the S atom in Rd 2 in the formula (d1-2). Yd 1 is a single bond or a divalent linking group. m is an integer of 1 or more, and M m+ are each independently an m-valent organic cation.]

[0402] {(d1-1) component} ·· Anion part In the formula (d1-1), Rd 1 is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof are the same as those of the above R' 201 . Among these, Rd 1Examples thereof include an aromatic hydrocarbon group which may have a substituent, an alicyclic group which may have a substituent, or a chain alkyl group which may have a substituent. Examples of the substituent which these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, a lactone-containing cyclic group represented by each of the general formulas (a2-r-1) to (a2-r-8), an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is included as a substituent, it may be via an alkylene group, and in this case, as the substituent, a substituent containing a linking group represented by each of the above formulas (L-al-1) to (L-al-8) is preferable. Note that Rd 1 When the aromatic hydrocarbon group, alicyclic group, or chain alkyl group in Rd 1 has a linking group represented by each of the general formulas (L-al-1) to (L-al-8) as a substituent, in the general formulas (L-al-1) to (L-al-8), Rd in the formula (d3-1) 101 is such that it is bonded to a carbon atom constituting the aromatic hydrocarbon group, alicyclic group, or chain alkyl group in Rd Examples of the aromatic hydrocarbon group preferably include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure composed of a bicyclooctane skeleton and another ring structure). Examples of the alicyclic group preferably include a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, or tetracyclododecane. The linear alkyl group preferably has 1 to 10 carbon atoms. Specifically, examples thereof include linear alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, and decyl group; branched-chain alkyl groups such as 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.

[0403] When the linear alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms, and even more preferably 1 to 4 carbon atoms. The fluorinated alkyl group may contain an atom other than a fluorine atom. Examples of the atom other than a fluorine atom include an oxygen atom, a sulfur atom, and a nitrogen atom.

[0404] Preferred specific examples of the anionic part of the component (d1-1) are shown below.

[0405]

Chemical formula

[0406] ···Cationic part In formula (d1-1), M m+ is an m-valent organic cation. M m+ Examples of the organic cation of M preferably include the same cations as those represented by the general formulas (ca-1) to (ca-3) respectively. The cation represented by the general formula (ca-1) is more preferable, and the cations represented by the formulas (ca-1-1) to (ca-1-84) are even more preferable. The component (d1-1) may be used alone or in combination of two or more.

[0407] {(d1-2) component} ··Anion part In formula (d1-2), Rd 2 is a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the above R’ 201 is the same as that. However, it is assumed that a fluorine atom is not bonded (not fluorine-substituted) to the carbon atom adjacent to the S atom in Rd 2 . As a result, the anion of the (d1-2) component becomes a moderately weak acid anion, and the quenching ability as the (D) component is improved. Rd 2 is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent, and more preferably an aliphatic cyclic group which may have a substituent.

[0408] The chain alkyl group preferably has 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. The aliphatic cyclic group includes a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, tetracyclododecane, etc. (which may have a substituent); and more preferably a group obtained by removing one or more hydrogen atoms from camphor.

[0409] Rd 2 's hydrocarbon group may have a substituent, and examples of the substituent are the same as those which the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in Rd 1 in formula (d1-1) may have.

[0410] The following shows preferred specific examples of the anion part of the (d1-2) component.

[0411]

Chemical formula

[0412] ··Cation part In formula (d1-2), M m+ is an m-valent organic cation, which is the same as M in the above formula (d1-1). m+ The same applies. The component (d1-2) may be used alone or in combination of two or more.

[0413] {(d1-3) component} ·· Anion part In formula (d1-3), Rd 3 is a cyclic group which may have a substituent, a linear alkyl group which may have a substituent, or a linear alkenyl group which may have a substituent, and examples thereof include the same as R' 201 , and it is preferably a cyclic group, a linear alkyl group, or a linear alkenyl group containing a fluorine atom. Among them, a fluorinated alkyl group is preferable, and the same as the fluorinated alkyl group of Rd 1 is more preferable.

[0414] In formula (d1-3), Rd 4 is a cyclic group which may have a substituent, a linear alkyl group which may have a substituent, or a linear alkenyl group which may have a substituent, and examples thereof include the same as R' 201 . Among them, it is preferably an alkyl group, an alkoxy group, an alkenyl group, or a cyclic group which may have a substituent. Rd 4 The alkyl group in Rd is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. may be mentioned. Some of the hydrogen atoms of the alkyl group of Rd 4 may be substituted with a hydroxyl group, a cyano group, etc. Rd 4The alkoxy group in is preferably an alkoxy group having 1 to 5 carbon atoms. Specific examples of the alkoxy group having 1 to 5 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group. Among them, a methoxy group and an ethoxy group are preferred.

[0415] Rd 4 The alkenyl group in is the same as the alkenyl group in the above R'. 201 Examples thereof include the same as the alkenyl group in the above R'. A vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferred. These groups may further have, as a substituent, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

[0416] Rd 4 The cyclic group in is the same as the cyclic group in the above R'. 201 Examples thereof include the same as the cyclic group in the above R'. An alicyclic group obtained by removing one or more hydrogen atoms from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclo[5.2.1.0 2,6 decane, or tetracyclododecane, or an aromatic group such as a phenyl group or a naphthyl group is preferred. When Rd 4 is an alicyclic group, the resist composition dissolves well in an organic solvent, and thus the lithography characteristics are good. Also, when Rd 4 is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition has excellent light absorption efficiency, and the sensitivity and lithography characteristics are good.

[0417] In formula (d1-3), Yd 1 is a single bond or a divalent linking group. Yd 1 The divalent linking group in is not particularly limited, and examples thereof include a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, a divalent linking group containing a hetero atom, and the like. Each of these is the same as Ya in the above formula (a2-1). 21In the description of the divalent linking group, examples thereof include the same as those of the divalent hydrocarbon group which may have a substituent and the divalent linking group containing a hetero atom. Yd 1 Preferably, it is a carbonyl group, an ester bond, an amide bond, an alkylene group or a combination thereof. As the alkylene group, a linear or branched alkylene group is more preferable, and a methylene group or an ethylene group is even more preferable.

[0418] Specific preferable examples of the anionic part of the component (d1-3) are shown below.

[0419]

Chemical formula

[0420]

Chemical formula

[0421] ···Cationic part In formula (d1-3), M m+ is an m-valent organic cation, which is the same as M in the above formula (d1-1). m+ The component (d1-3) may be used alone or in combination of two or more.

[0422] The component (D1) may use only any one of the above components (d1-1) to (d1-3), or may use a combination of two or more. When the resist composition contains the component (D1), the content of the component (D1) in the resist composition is preferably 0.5 to 15 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 15 parts by mass with respect to 100 parts by mass of the component (A).

[0423] The component (D1) preferably contains the above component (d1-1). ​Among the whole components of (D1), the content of the component (d1-1) is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 90% by mass or more, and the component (D1) may consist only of the compound (d1-1) component.

[0424] Production method of component (D1): The production methods of the above-mentioned components (d1-1) and (d1-2) are not particularly limited and can be produced by known methods. Also, the production method of the component (d1-3) is not particularly limited and is produced, for example, in the same manner as the method described in US2012-0149916. As an example of the base component ((D) component) that traps the acid generated by exposure, the compound of the component (D1) was shown, but the compound of the component (D1) may be used as the component (B). For example, in the resist composition of the present embodiment, a compound of the component (D1) is used as the component (B), and a compound that generates an acid with a lower acidity than the acid generated by exposure of the compound of the component (D1) is used as the component (D). Also, in the resist composition of the present embodiment, a compound of the component (D1) is used as the component (B), and the component (D2) described later may be used as the component (D).

[0425] ·Regarding the component (D2) As the component (D), a nitrogen-containing organic compound component that does not correspond to the above-mentioned component (D1) (hereinafter referred to as "component (D2)") may be contained. The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not correspond to the component (D1), and can be arbitrarily used from known ones. Among them, 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 the aliphatic group preferably has 1 to 12 carbon atoms. Examples of the aliphatic amine include an amine (alkylamine or alkyl alcohol amine) in which at least one hydrogen atom of ammonia NH3 is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms, or a cyclic amine. Specific examples of the alkylamine and alkyl alcohol amine 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 alcohol amines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 6 to 30 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

[0426] Examples of the cyclic amine include, for example, a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine). Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable, and specific 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.

[0427] Examples of 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., and triethanolamine triacetate is preferred.

[0428] Also, as the component (D2), an aromatic amine may be used. Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine, 2,6-di-tert-butylpyridine, 2,6-di-tert-butylpyridine, etc.

[0429] The component (D2) may be used alone or in combination of two or more. When the resist composition contains the component (D2), the content of the component (D2) in the resist composition is usually in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the component (A). By setting the range as above, the resist pattern shape, standing stability over time, etc. are improved.

[0430] In the resist composition of this embodiment, it is preferable that the quencher component is incorporated into the component (A1) as the structural unit (a6-0). When the component (A1) has the structural unit (a6-0), it is preferable that the resist composition does not contain the component (D).

[0431] <At least one compound (E) selected from the group consisting of an organic carboxylic acid and an oxo acid of phosphorus and its derivatives> In the resist composition of the present embodiment, for the purpose of preventing sensitivity deterioration and improving resist pattern shape, standing stability over time, etc., as optional components, an organic carboxylic acid and at least one compound (E) selected from the group consisting of oxo acids of phosphorus and their derivatives (hereinafter referred to as "(E) component") can be contained. Specific examples of the organic carboxylic acid include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, etc. Among them, salicylic acid is preferred. Examples of the oxo acid of phosphorus include phosphoric acid, phosphonic acid, phosphinic acid, etc. Among them, phosphonic acid is particularly preferred.

[0432] In the resist composition of the present embodiment, the (E) component may be used alone or in combination of two or more. When the resist composition contains the (E) component, the content of the (E) component is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, based on 100 parts by mass of the (A) component. By setting the content within the above range, the lithography characteristics can be further improved.

[0433] <Fluorine additive component (F)> The resist composition of the present embodiment may contain a fluorine additive component (hereinafter referred to as "(F) component") as a hydrophobic resin. The (F) component is used to impart water repellency to the resist film, and by using it as a resin different from the (A) component, the lithography characteristics can be improved. As the (F) component, for example, fluorine-containing polymer compounds described in JP-A-2010-002870, JP-A-2010-032994, JP-A-2010-277043, JP-A-2011-13569, and JP-A-2011-128226 can be used. (F) More specifically as the component, polymers having a structural unit (f1) represented by the following general formula (f1-1) can be mentioned. As this polymer, a polymer (homopolymer) consisting only of the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) and the structural unit (a1); a copolymer of the structural unit (f1), a structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1) is preferable, and a copolymer of the structural unit (f1) and the structural unit (a1) is more preferable. Here, as the structural unit (a1) copolymerized with the structural unit (f1), a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate and a structural unit derived from 1-methyl-1-adamantyl (meth)acrylate are preferable, and a structural unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate is more preferable.

[0434] [Chemical formula] [In the formula, R is the same as above, Rf 102 and Rf 103 each independently represent 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 may be the same or different. nf 1 is an integer of 0 to 5, and Rf 101 is an organic group containing a fluorine atom. Lf 101 represents a divalent linking group.]

[0435] In formula (f1-1), R bonded to the carbon atom at the α-position is the same as above. As R, a hydrogen atom or a methyl group is preferable. In formula (f1-1), Rf 102 and Rf 103 As the halogen atom, a fluorine atom is preferable. As the alkyl group having 1 to 5 carbon atoms of Rf 102 and Rf 103 the same ones as the alkyl group having 1 to 5 carbon atoms of the above R can be mentioned, and a methyl group or an ethyl group is preferable. Rf102 and Rf 103 Examples of the C1-5 haloalkyl group of and Rf include groups in which some or all of the hydrogen atoms of the C1-5 alkyl group are substituted with halogen atoms. The halogen atom is preferably a fluorine atom. Among them, Rf 102 and Rf 103 are preferably a hydrogen atom, a fluorine atom, or a C1-5 alkyl group, 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 of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.

[0436] In formula (f1-1), Rf 101 is an organic group containing a fluorine atom, preferably a hydrocarbon group containing a fluorine atom. The hydrocarbon group containing a fluorine atom may be linear, branched, or cyclic, preferably having 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and particularly preferably 1 to 10 carbon atoms. In addition, in the hydrocarbon group containing a fluorine atom, 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 preferably 60% or more are fluorinated because the hydrophobicity of the resist film during immersion exposure is increased. Among them, Rf 101 is more preferably a C1-6 fluorinated hydrocarbon group, and particularly preferably a trifluoromethyl group, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, -CH2-CH2-CF2-CF2-CF2-CF3.

[0437] In formula (f1-1), examples of the divalent linking group in Lf 101 include the same ones as the divalent linking group in Ya x1 in the above formula (a10-1). Lf 101As the divalent linking group in [the relevant context], an aromatic hydrocarbon group which may have a substituent or a divalent linking group containing a heteroatom is preferable. As the aromatic hydrocarbon group which may have a substituent, a group in which one of the hydrogen atoms of an arylene group which may have a substituent is substituted with -COO- is preferable. For example, as the aromatic hydrocarbon group which may have a substituent, -Ar in the above formula (a0-z) 0 A group represented by -COO- is preferable. As the divalent linking group containing a heteroatom, a divalent linking group containing an ether bond or an ester bond is preferable, and -COO- is more preferable. For example, -Lf in the formula (f1-1) 10 -CRf 102 Rf 103 A group represented by - is preferably a group represented by -COO-CRf 102 Rf 103 - represented by.

[0438] The weight average molecular weight (Mw) (in terms of polystyrene conversion standard by gel permeation chromatography) of the component (F) is preferably from 1000 to 50000, more preferably from 5000 to 40000, and most preferably from 10000 to 30000. When it is below the upper limit value of this range, there is sufficient solubility in the resist solvent for use as a resist, and when it is above the lower limit value of this range, the water repellency of the resist film is good. The dispersity (Mw / Mn) of the component (F) is preferably from 1.0 to 5.0, more preferably from 1.0 to 3.0, and most preferably from 1.0 to 2.5.

[0439] In the resist composition of this embodiment, the component (F) may be used alone or in combination of two or more. When the resist composition contains the component (F), the content of the component (F) is preferably from 0.5 to 10 parts by mass, more preferably from 1 to 10 parts by mass, based on 100 parts by mass of the component (A).

[0440] <Organic solvent component (S)> The resist composition of the present embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as "(S) component"). In the resist composition of the present embodiment, the (S) component may be used alone or as a mixed solvent of two or more components. Among them, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), γ-butyrolactone, ethyl lactate (EL), and cyclohexanone are preferable.

[0441] Also, as the (S) component, a mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent. As the (S) component, a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, as the mixing ratio, the mass ratio of the former to the latter is preferably 70:30 to 95:5. The amount of the (S) component used is not particularly limited and is appropriately set according to the coating film thickness at a concentration that can be applied to a substrate or the like. Generally, the (S) component 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.

[0442] After dissolving the above resist material in the (S) component, the resist composition of the present embodiment may be subjected to removal of impurities or the like using a polyimide porous membrane, a polyamideimide 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 polyamideimide porous membrane, a filter made of a polyimide porous membrane and a polyamideimide porous membrane, or the like. Examples of the polyimide porous membrane and the polyamideimide porous membrane include those described in JP-A-2016-155121.

[0443] The resist composition of the present embodiment described above contains component (A1) having structural unit (a01) and structural unit (a02). Thereby, a resist composition with high sensitivity and reduced roughness is realized. The reason for such an effect is presumed as follows. Both structural unit (a01) and structural unit (a02) have a structure in which a group represented by -Ar is bonded to a carbon atom constituting the main chain of the polymer. 0 Therefore, when synthesizing component (A1) by polymerizing each monomer that induces each structural unit of component (A1), it is considered that the participation rates of the monomers that induce structural unit (a01) and structural unit (a02) become uniform. Thereby, in component (A1), it is considered that the distribution of structural unit (a01) and structural unit (a02) becomes uniform. In the exposed portion of the resist film, structural unit (a01) acts as a proton source, and structural unit (a02) acts as an acid generator. Therefore, it is considered that the variation in acid generation in the exposed portion is suppressed by the uniform distribution of structural unit (a01) and structural unit (a02). Furthermore, it is considered that the variation in solubility during development is suppressed. It is presumed that by the above-described actions working synergistically, the sensitivity and roughness can be freed from the trade-off relationship, and both an improvement in sensitivity and a reduction in roughness can be achieved.

[0444] In addition, when component (A1) has other structural units other than structural unit (a01) and structural unit (a02), it is preferable that the other structural units also have a structure represented by the general formula (a0-z). By increasing the proportion of the structural unit represented by the general formula (a0-z) in component (A1), it is considered that the distribution of each structural unit in component (A1) can be made more uniform. Thereby, it is considered that further reduction of roughness can be achieved.

[0445] Further, in the resist composition of the present embodiment, it is preferable that the proportion of the component contained as the structural unit (a0-z) represented by the general formula (a0-z) is larger among all solid components contained in the resist composition. By incorporating each component of the resist composition as the structural unit (a0-z) into the component (A1), it is considered that the distribution of each component can be made more uniform. Thereby, it is considered that further reduction of roughness can be achieved.

[0446] (Resist Pattern Formation Method) The resist pattern formation method according to the second aspect of the present invention includes a step of forming a resist film on a support using the resist composition according to the first aspect of the present invention described above, a step of exposing the resist film, and a step of developing the exposed resist film to form a resist pattern. As an embodiment of such a resist pattern formation method, for example, a resist pattern formation method performed as follows can be mentioned.

[0447] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and a baking (post-apply bake (PAB)) treatment is performed at a temperature condition of, for example, 80 to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds to form a resist film. Next, selective exposure is performed on the resist film by exposure through a mask (mask pattern) having a predetermined pattern formed thereon or by direct irradiation with an electron beam without passing through the mask pattern using an exposure apparatus such as an electron beam lithography apparatus or an ArF exposure apparatus. Then, a baking (post-exposure bake (PEB)) treatment is performed at a temperature condition of, for example, 80 to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds. Next, the resist film is developed. In the case of an alkali development process, an alkali developer is used, and in the case of a solvent development process, a developer containing an organic solvent (organic-based developer) is used.

[0448] After the development process, preferably a rinsing process is performed. In the case of an alkaline development process, water rinsing with pure water is preferred, and in the case of a solvent development process, it is preferable to use a rinsing solution containing an organic solvent. In the case of a solvent development process, after the development process or the rinsing process, a process of removing the developer or the rinsing solution adhering to the pattern with a supercritical fluid may be performed. After the development process or the rinsing process, drying is performed. Also, in some cases, a baking process (post-bake) may be performed after the above development process.

[0449] The support is not particularly limited, and conventionally known ones can be used. For example, substrates for electronic components and those with a predetermined wiring pattern formed thereon can be mentioned. More specifically, silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, and glass substrates can be mentioned. As the material for the wiring pattern, for example, copper, aluminum, nickel, gold, etc. can be used.

[0450] The wavelength used for exposure is not particularly limited, and it can be performed using radiation such as ArF excimer laser, KrF excimer laser, F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. The resist pattern forming method of the present embodiment is particularly useful in the method of exposing the resist film to EUV (extreme ultraviolet) or EB (electron beam) in the step of exposing the resist film.

[0451] The exposure method of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or liquid immersion exposure (Liquid Immersion Lithography). Liquid immersion exposure is an exposure method in which the space between the resist film and the lens at the lowest position of the exposure apparatus is filled with a solvent (liquid immersion medium) having a refractive index greater than that of air in advance, and 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 to be exposed is preferable. For example, water, fluorine-based inert liquids, silicon-based solvents, hydrocarbon-based solvents, etc. may be mentioned. Water is preferably used as the immersion medium.

[0452] As the alkaline developer used for development in the alkaline development process, for example, a 0.1 to 10 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) may be mentioned. As the organic solvent contained in the organic developer used for development in the solvent development process, any one can be used as long as it can dissolve the component (A) (component (A) before exposure), and it can be appropriately selected from known organic solvents. Specifically, polar solvents such as ketone-based solvents, ester-based solvents, alcohol-based solvents, nitrile-based solvents, amide-based solvents, ether-based solvents, etc., hydrocarbon-based solvents, etc. may be mentioned.

[0453] Examples of the ester-based solvent 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.

[0454] Examples of the nitrile-based solvent include acetonitrile, propionitrile, valeronitrile, butyronitrile, etc.

[0455] Known additives can be incorporated into the organic developer as necessary. Examples of such additives include surfactants. The surfactant is not particularly limited, and for example, ionic or non-ionic fluorine-based and / or silicon-based surfactants can be used.

[0456] The development process can be carried out by known development methods. For example, a method of immersing the support in the developer for a certain period of time (dip method), a method of raising the developer on the surface of the support by surface tension and allowing it to stand still for a certain period of time (paddle method), a method of spraying the developer on the surface of the support (spray method), a method of continuously discharging the developer while scanning the developer discharge nozzle at a constant speed on a support rotating at a constant speed (dynamic dispense method), etc. can be mentioned.

[0457] As the organic solvent contained in the rinse liquid used for the rinse treatment after the development process in the solvent development process, for example, among the organic solvents mentioned as the organic solvent used for the organic developer, those that are difficult to dissolve the resist pattern can be appropriately selected and used. Usually, 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 alone or in combination of two or more. Also, they may be used in mixture with organic solvents other than the above and water.

[0458] The rinse treatment (cleaning treatment) using the rinse liquid can be carried out by known rinse methods. Examples of the method of this rinse treatment include a method of continuously discharging the rinse liquid on a support rotating at a constant speed (spin coating method), a method of immersing the support in the rinse liquid for a certain period of time (dip method), a method of spraying the rinse liquid on the surface of the support (spray method), etc.

[0459] According to the resist pattern forming method of the present embodiment described above, since the above-described resist composition is used, when forming a resist pattern, a resist pattern with improved sensitivity and suppressed roughness of the resist pattern can be formed.

[0460] In the resist composition of the above-described embodiment and various materials used in the pattern forming method of the above-described embodiment (for example, resist solvent, developer, rinse liquid, composition for forming an antireflection film, composition for forming a top coat, etc.), it is preferable that they do not contain impurities such as metals, metal salts containing halogens, acids, alkalis, components containing sulfur atoms or phosphorus atoms. Here, examples of impurities containing metal atoms include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The content of impurities contained in these materials is preferably 200 ppb or less, more preferably 1 ppb or less, still more preferably 100 ppt (parts per trillion) or less, particularly preferably 10 ppt or less, and most preferably substantially not contained (below the detection limit of the measuring device).

[0461] (Polymer compound) The polymer compound according to the third aspect of the present invention has a structural unit (a01) represented by the general formula (a01) and a structural unit (a02) represented by the general formula (a02). The structural unit (a01) and the structural unit (a02) are the same as those described above. The polymer compound of the present embodiment is the same as the component (A) described in the resist composition according to the first aspect. The polymer compound of the present embodiment can be used for the production of the resist composition according to the first aspect.

Examples

[0462] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0463] <Synthesis example of compound> (Synthesis example of compound (M-1)) ≪Synthesis of compound (Pre-M1a)≫ 3,5-Diiodosalicylic acid (40.0 g) and tetrahydrofuran (THF) (160.0 g) were charged and stirred until dissolved. To this, 1,1'-carbonyldiimidazole (CDI) (20.0 g) was added, and then the temperature was raised to 60 °C in a water bath and stirred for 1 hour. Compound (1a) (38.3 g) was added thereto and aged for 1 hour. Thereafter, ultrapure water (160.0 g) and dichloromethane (160.0 g) were charged and stirred. After stopping the stirring, the aqueous layer was removed and further washed with ultrapure water (160 g). The organic layer was concentrated under reduced pressure, and the concentrated residue was crystallized from acetonitrile / tert-butyl methyl ether to obtain 43.2 g of a white intermediate (Pre-M1a).

[0464] ≪Synthesis of Compound (Pre-M1b)≫ 4-Vinylbenzoic acid (9.6 g), compound (Pre-M1a) (40.0 g), 4-dimethylaminopyridine (DMAP) (0.7 g), and dichloromethane (400.0 g) were mixed and stirred at 0 °C. 1,3-Diisopropylcarbodiimide (DIC) (8.9) was added thereto. After stirring at room temperature for 3 hours, it was concentrated under reduced pressure. The concentrated residue was crystallized from acetonitrile / tert-butyl methyl ether to obtain 31.5 g of a white compound (Pre-M1b).

[0465] ≪Synthesis of Compound (M-1)≫ Compound (Pre-M1b) (30.0 g), compound (1b) (21.3 g), dichloromethane (150.0 g), and ultrapure water (60.0 g) were mixed, stirred at room temperature, and separated. The organic layer was washed 5 times with ultrapure water (60.0 g) and then concentrated under reduced pressure to obtain 30.5 g of compound (M-1).

[0466]

Chemical formula

[0467] For the obtained compound (M-1), NMR measurement was performed, and its structure was identified from the following analysis results. 1H-NMR (DMSO-d6, 400 MHz): δ (ppm) = 8.58 (m, 3H), 8.31 (m, 3H), 8.13 (d, 2H), 8.00 - 7.72 (m, 11H), 6.92 - 6.85 (m, 1H), 6.07 (d, 1H), 5.49 (d, 1H), 4.67 (t, 2H)

[0468] (Synthesis Example of Compound (M-2)) Compound (M-2) was synthesized in the same manner as in the synthesis example of the above-mentioned (Compound (M-1)), except that compound (1c) was used instead of 4-vinylbenzoic acid.

[0469] [Chemical Structure Diagram]

[0470] For the obtained compound (M-2), NMR measurement was carried out, and its structure was identified from the following analysis results.

[0471] Compound (B0-2): 1H-NMR (DMSO-d6, 400 MHz): δ (ppm) = 10.63 (s, 1H), 8.25 (d, 1H), 8.04 (d, 1H), 8.01 - 7.64 (m, 17H), 7.23 (s, 1H), 6.81 - 6.763 (m, 1H), 5.97 (d, 1H), 5.35 (d, 1H), 4.83 (t, 2H)

[0472] (Synthesis Example of Compound (M-3)) <<Synthesis of Compound (Pre-M3a)>> 100 g of 4-vinylbenzoic acid, 331 g of 2,4-diiodo-5-tert-butoxycarbonylphenol, and 8.3 g of dimethylaminopyridine were dissolved in 800 g of dichloromethane, and 102 g of N,N'-diisopropylcarbodiimide (DIC) was added dropwise to the solution under ice cooling. After stirring at room temperature for 4 hours, the reaction solution was filtered. 308 g of trifluoroacetic acid (TFA) was added to the filtrate, and the mixture was stirred at room temperature for 24 hours. The solvent was distilled off, and 200 g of methanol was added to the residue. The solution was added dropwise to 800 g of t-methylbutyl ether, and the precipitated crystals were filtered and dried to obtain 252 g of compound (Pre-M3a).

[0473] ≪Synthesis of Compound (Pre-M3b)≫ 100 g of compound (Pre-M3a) was dissolved in 800 g of methyl isobutyl ketone, and 88.4 g of a 40% aqueous solution of benzyltrimethylammonium hydroxide and 600 g of ultrapure water were added. After stirring at room temperature for 2 hours, the aqueous layer was removed, and the organic layer was washed 3 times with 600 g of ultrapure water. Then, the solvent was distilled off from the organic layer to obtain 122 g of compound (Pre-M3b).

[0474] ≪Synthesis of Compound (M-3)≫ 85 g of compound (Pre-M3b) was dissolved in 800 g of dichloromethane, 51.3 g of compound (1b) and 800 g of ultrapure water were added, and the mixture was stirred at room temperature for 1 hour. After removing the aqueous layer, the organic layer was washed 3 times with 800 g of ultrapure water. The solvent was distilled off from the organic layer to obtain 96 g of compound (M-3).

Chemical Structure

[0475] For the obtained compound (M-3), NMR measurement was performed, and its structure was identified from the following analysis results.

[0476] Compound (B0-4): 1H-NMR (DMSO-d6, 400 MHz): δ (ppm) = 8.12 (d, 2H), 8.00 - 7.70 (m, 19H), 6.70 (t, 1H), 5.71 (d, 1H), 5.19 (d, 1H)

[0477] <Production of Polymer Compound> (Synthesis of Polymer Compound (A1-1)) Compound (M-1) (24.0 g), Compound (M-2) (28.8 g), Compound (M-3) (28.9 g), and 2,2'-Azobis(2-methylpropionitrile) dimethyl (V-601, 5.75 g) as a polymerization initiator were dissolved in methyl ethyl ketone (MEK) (145 g) to prepare a dropping solution. MEK (100 g) was added to a three-necked flask equipped with a thermometer, a reflux tube, and a nitrogen inlet tube, heated to 85°C under a nitrogen atmosphere, and the above dropping solution was added dropwise over 4 hours. After completion of the addition, the reaction solution was stirred at 85°C for 1 hour. Then, the reaction solution was cooled to room temperature. After completion of the reaction, the obtained reaction solution was precipitated with heptane (500 g), and the precipitate was washed. The obtained white solid was filtered and dried under reduced pressure overnight to obtain a polymer compound (A1-1).

[0478]

Chemical Structure

[0479] (Synthesis of Polymer Compounds (A1-2) to (A1-25)) Polymer compounds (A1-2) to (A1-25) were each synthesized in the same manner as the synthesis of polymer compound (A1-1), except that the compounds used in the polymerization reaction were changed.

[0480] Polymer compounds (A1-1) to (A1-25) are shown below. In the following formula, l, m, n, o, and q represent the composition ratios (molar ratios) of the respective structural units.

[0481]

Chemical Structure

[0482]

Chemical Structure

[0483]

Chemical Structure

[0484] [Chemical formula]

[0485] [Chemical formula]

[0486] [Chemical formula]

[0487] [Chemical formula]

[0488] (Synthesis of Polymer Compounds (A2-1) to (A2-3) in Comparative Examples) Polymer compounds (A2-1) to (A2-3) were synthesized in the same manner as the synthesis of polymer compound (A1-1), except that the compounds used in the polymerization reaction were changed.

[0489] Polymer compounds (A2-1) to (A2-3) are shown below. In the following formulae, l, m, and n represent the composition ratios (molar ratios) of the respective structural units.

[0490] [Chemical formula]

[0491] For the obtained polymer compounds (A1-1) to (A1-25) and (A2-1) to (A2-3), the weight-average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were determined by GPC measurement (in terms of standard polystyrene). Also, for the polymer compounds (A1-1) to (A1-25) and (A2-1) to (A2-3), the copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) was determined by carbon-13 nuclear magnetic resonance spectrum (600 MHz,13 It was determined by 13C-NMR). The results are shown in Table 1.

[0492] [Table 1]

[0493] <Preparation of Resist Composition> (Examples 1 to 25, Comparative Examples 1 to 3) The resist compositions of each example were prepared by mixing and dissolving the components shown in Tables 1 to 3, respectively.

[0494] [Table 2]

[0495] [Table 3]

[0496] [Table 4]

[0497] In Tables 1 to 3, each abbreviation has the following meaning. The numerical values in [ ] are the blending amounts (parts by mass). (A1)-1 to (A1)-25: The above polymer compounds (A1-1) to (A1-25). (A2)-1 to (A2)-3: The above polymer compounds (A2-1) to (A2-3).

[0498] (D1)-1: An acid diffusion control agent composed of a compound represented by the following chemical formula (D1-1).

[0499] [Chemical Formula]

[0500] (S)-1: Propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 / 40 (mass ratio) mixed solvent.

[0501] <Formation of resist pattern> Step of forming a resist film: On an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS), each resist composition was applied using a spinner, and pre-baked (PAB) at a temperature of 110 °C for 60 seconds on a hot plate and dried to form a resist film with a thickness of 50 nm.

[0502] Step of exposing the resist film: Next, using an electron beam lithography apparatus JEOL-JBX-9300FS (manufactured by JEOL Ltd.), the resist film was exposed (lithographed) at an acceleration voltage of 100 kV with a target size of a 1:1 line and space pattern (hereinafter referred to as "LS pattern") with a line width of 50 nm, and then post-exposure bake (PEB) treatment was performed at 100 °C for 60 seconds.

[0503] Step of developing the exposed resist film: Next, at 23 °C, using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.), alkali development was performed for 60 seconds, and then water rinsing treatment was performed for 15 seconds using pure water. As a result, a 1:1 LS pattern with a line width of 50 nm was formed.

[0504] [Evaluation of optimum exposure dose (Eop)] The optimum exposure dose Eop (μC / cm 2 ) at which the CH pattern of the target size is formed by the above <Formation of resist pattern> was determined. This is shown in Tables 4 to 6 as "Eop (μC / cm 2 )".

[0505] [Evaluation of LWR (Line Width Roughness)] For the LS pattern formed in the above <formation of resist pattern>, 3σ, which is a measure indicating LWR, was determined. "3σ" is a three-fold value (3σ) (unit: nm) of the standard deviation (σ) obtained from measuring the line positions at 400 locations in the longitudinal direction of the line using a scanning electron microscope (acceleration voltage: 800 V, product name: S-9380, manufactured by Hitachi High-Technologies Corporation). The smaller the value of 3σ, the smaller the roughness of the line sidewall, meaning that a more uniform-width LS pattern was obtained. The results are shown in Tables 4 to 6 as "LWR (nm)".

[0506]

Table 5

[0507]

Table 6

[0508]

Table 7

[0509] As shown in Tables 4 to 6, it was confirmed that the resist compositions of Examples 1 to 25 are superior in both sensitivity and LWR compared to the resist compositions of Comparative Examples 1 to 3.

Claims

1. A resist composition that generates an acid upon exposure and whose solubility in a developer changes due to the action of the acid, containing a resin component (A1) whose solubility in a developer changes due to the action of the acid, wherein the resin component (A1) has a structural unit (a01) represented by the following general formula (a01) and a structural unit (a02) represented by the following general formula (a02), resist composition. 【Chemical Formula 1】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Ar ０１ represents an aromatic hydrocarbon group which may have a substituent. m0 represents an integer of 1 or more as long as the valence allows. Y ０２ represents a single bond or a divalent linking group. Rf ０２ represents a divalent linking group containing a fluorine atom. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

2. The resist composition according to claim 1, wherein the resin component (A1) further has a structural unit represented by the following general formula (a1-0). 【Chemical Formula 2】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y １０ represents a hydrocarbon group which may have a substituent. Rx １０ represents an acid dissociable group. m10 represents an integer of 0 to 2. ]

3. The resist composition according to claim 1 or 2, wherein the resin component (A1) further has a structural unit represented by the following general formula (a2-0). 【Chemical Formula 3】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ２０ represents a single bond or a divalent linking group. Rx ２０ represents a lactone-containing cyclic group. ]

4. The resist composition according to claim 1 or 2, wherein the resin component (A1) further has a structural unit represented by the following general formula (a6-0). [Chemical Formula 4] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ６０ represents a divalent linking group. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

5. The resist composition according to claim 3, wherein the resin component (A1) further has a structural unit represented by the following general formula (a6-0). [Chemical Formula 5] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ６０ represents a divalent linking group. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

6. A resist pattern forming method, comprising a step of forming a resist film using the resist composition according to claim 1 or 2 on a support, a step of exposing the resist film, and a step of developing the resist film after the exposure to form a resist pattern.

7. A polymer compound having a structural unit (a01) represented by the following general formula (a01) and a structural unit (a02) represented by the following general formula (a02). [Chemical Formula 6] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Ar ０１ represents an aromatic hydrocarbon group which may have a substituent. m0 represents an integer of 1 or more as long as the valence allows. Y ０２ represents a single bond or a divalent linking group. Rf ０２ represents a divalent linking group containing a fluorine atom. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

8. The polymer compound according to claim 7, further having a structural unit represented by the following general formula (a1-0). 【Chemical formula 7】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y １０ represents a hydrocarbon group which may have a substituent. Rx １０ represents an acid dissociable group. m10 represents an integer of 0 to 2. ]

9. The polymer compound according to claim 7 or 8, further having a structural unit represented by the following general formula (a2-0). 【Chemical formula 8】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ２０ represents a single bond or a divalent linking group. Rx ２０ represents a lactone-containing cyclic group. ]

10. The polymer compound according to claim 7 or 8, further having a structural unit represented by the following general formula (a6-0). 【Chemical formula 9】 [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ６０ represents a divalent linking group. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

11. The polymer compound according to claim 9, further having a structural unit represented by the following general formula (a6-0). [Chemical Formula 10] [In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ar ０ represents an aromatic hydrocarbon group which may have a substituent. Y ６０ represents a divalent linking group. m is an integer of 1 or more, and M ｍ＋ is an m-valent cation. ]

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