Resist composition, method for forming a resist pattern, compound, acid generator, acid diffusion controller, and polymer compound

Abstract

To provide: a resist composition having high sensitivity and excellent lithography characteristics such as defect; a method for forming a resist pattern by using the resist composition; and a compound, an acid generator, a photodegradable base, and a polymer compound to be used for the resist composition.SOLUTION: A resist composition generates an acid by exposure and its solubility in a developer changes by an action of an acid, and contains a compound including a cation (C0) represented by general formula (c0). X01 is an electron-withdrawing group, X02 is an electron-withdrawing group different from X01, and R01 is an electron-donating group. R02 and R03 are mutually independently substituents. nx1 and nx2 are mutually independently integers of 1 to 4. n1 is an integer of 0 to 3. nx1+nx2+n1≤5. n2 and n3 are mutually independently integers of 0 to 4.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resist composition, a method of forming a resist pattern, a compound, an acid generator, an acid diffusion controller, and a polymer compound. [Background technology]

[0002] In recent years, advances in lithography technology have led to rapid advances in the miniaturization of patterns in the manufacturing of semiconductor devices and liquid crystal display devices. A common method for achieving this miniaturization is to shorten the wavelength (increase the energy) of the exposure light source.

[0003] Resist materials are required to have lithography properties such as sensitivity to these exposure light sources and resolution capable of reproducing patterns with minute dimensions. To satisfy these requirements, a chemically amplified resist composition has been used, which contains a base component whose solubility in a developer changes due to the action of acid, and an acid generator component that generates acid upon exposure.

[0004] Chemically amplified resist compositions generally contain resins having multiple structural units in order to improve lithography properties and the like. In the formation of a resist pattern, the behavior of the acid generated from the acid generator component upon exposure is also considered to be a factor that has a significant effect on lithography properties. A wide variety of acid generators have been proposed for use in chemically amplified resist compositions, including, for example, onium salt-based acid generators such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generators, diazomethane-based acid generators, nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

[0005] For example, Patent Document 1 discloses a resist composition that employs, as an acid generator, a compound in which an electron-withdrawing group is introduced into a sulfonium cation. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-207404 Summary of the Invention [Problem to be solved by the invention]

[0007] As resist patterns become increasingly finer, for example, in EUV and EB lithography, the goal is to form fine patterns of several tens of nanometers. As resist patterns become finer, improving sensitivity and reducing defects have become important issues.

[0008] The present invention has been made in light of the above circumstances, and an object of the present invention is to provide a resist composition that has high sensitivity and exhibits favorable lithography properties such as reduced defects; a method of forming a resist pattern that uses the resist composition; and a compound, an acid generator, an acid diffusion controller, and a polymeric compound that are used in the resist composition. [Means for solving the problem]

[0009] 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 due to the action of the acid, the resist composition comprising a compound that contains a cation (C0) represented by the following general formula (c0):

[0010] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.]

[0011] A second aspect of the present invention is a method of forming a resist pattern, comprising the steps of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film to light, and developing the exposed resist film to form a resist pattern.

[0012] A third aspect of the present invention is a compound represented by the following general formula (M0).

[0013] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.]

[0014] A third aspect of the present invention is an acid generator containing a compound represented by the following general formula (B0).

[0015] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same or different. - is the counter anion.

[0016] A fourth aspect of the present invention is an acid diffusion controller containing a compound represented by the following general formula (D0).

[0017] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same or different. - is the counter anion.

[0018] A fifth aspect of the present invention is a polymeric compound having a structural unit (a0) represented by the following general formula (A0-1).

[0019] [ka] [In the formula, R is a hydrogen atom, a carbon atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.] 0 is a group containing an anion. 01 is an electron-withdrawing group, and X 02 is X 01 R is an electron-withdrawing group different from 01 is an electron-donating group. 02 and R 03are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.] [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a resist composition that has high sensitivity and exhibits favorable lithography properties such as low defect levels, a method of forming a resist pattern that uses the resist composition, and a compound, an acid generator, an acid diffusion controller, and a polymeric compound that are used in the resist composition. DETAILED DESCRIPTION OF THE INVENTION

[0021] In this specification and claims, the term "aliphatic" is defined as a relative concept to aromatic, and refers to groups, compounds, etc. that do not have aromaticity. Unless otherwise specified, the term "alkyl group" includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to alkyl groups in alkoxy groups. Unless otherwise specified, the term "alkylene group" includes linear, branched and cyclic divalent saturated hydrocarbon groups. The "halogen atom" includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The term "structural unit" refers to a monomer unit that constitutes a polymeric compound (resin, polymer, copolymer). The phrase "may have a substituent" includes both the case where a hydrogen atom (-H) is replaced with a monovalent group and the case where a methylene group (-CH2-) is replaced with a divalent group. The term "exposure" is a general concept that includes irradiation with radiation.

[0022] The term "acid-decomposable group" refers to a group having acid decomposability in which at least some of the bonds in the structure of the acid-decomposable group can be cleaved by the action of an acid. Examples of acid-decomposable groups whose polarity increases under the action of an acid include groups that decompose under the action of an acid to generate a polar group. Examples of polar groups include a carboxy group, a hydroxyl group, an amino group, and a sulfo group (-SO3H). More specific examples of the acid-decomposable group include groups in which the polar group is protected with an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).

[0023] The term "acid-dissociable group" refers to either (i) a group having acid dissociability such that the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group can be cleaved by the action of an acid, or (ii) a group in which a portion of the bond is cleaved by the action of an acid, and then a decarboxylation reaction occurs, thereby cleaving the bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group. The acid-dissociable group constituting the acid-decomposable group must be a group with lower polarity than the polar group generated by dissociation of the acid-dissociable group. Therefore, 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 component (A1) increases. The increase in polarity relatively changes the solubility in the developer, increasing the solubility when the developer is an alkaline developer and decreasing the solubility when the developer is an organic developer.

[0024] A "base component" is an organic compound that has film-forming ability. Organic compounds used as base components are broadly divided into non-polymers and polymers. Non-polymers typically have a molecular weight of 500 or more and less than 4000. Hereinafter, the term "low molecular weight compound" refers to a non-polymer with a molecular weight of 500 or more and less than 4000. Polymers typically have a molecular weight of 1000 or more. Hereinafter, the terms "resin," "high molecular weight compound," or "polymer" refer to a polymer with a molecular weight of 1000 or more. The molecular weight of a polymer is determined by the weight average molecular weight converted into polystyrene by GPC (gel permeation chromatography).

[0025] The term "derived structural unit" refers to a structural unit formed by cleavage of a multiple bond between carbon atoms, such as an ethylenic double bond. In the "acrylic acid ester", the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. αx ) is an atom or group other than a hydrogen atom. αx ) is substituted with a substituent containing an ester bond, or αx This also includes α-hydroxyacrylic esters in which the hydroxyl group is substituted with a hydroxyalkyl group or a group that modifies the hydroxyl group. Unless otherwise specified, the α-carbon atom of an acrylic ester refers to the carbon atom to which the carbonyl group of acrylic acid is bonded. Hereinafter, an acrylic ester in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic ester.

[0026] The term "derivative" encompasses compounds in which the 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 compounds in which the hydrogen atom of a hydroxyl group of a target compound, which may have the hydrogen atom at the α-position substituted with a substituent, is substituted with an organic group; and compounds in which a substituent other than a hydroxyl group is bonded to a target compound, which may have the hydrogen atom at the α-position substituted with a substituent. Unless otherwise specified, the α-position refers to the first carbon atom adjacent to the functional group. The substituents that replace the hydrogen atom at the α-position of hydroxystyrene include R αx The same can be mentioned.

[0027] In this specification and claims, some structures represented by chemical formulas may have asymmetric carbon atoms, and may exist as enantiomers or diastereomers. In such cases, a single chemical formula represents all isomers. These isomers may be used alone or as a mixture.

[0028] (Resist composition) The resist composition according to the first aspect of the present invention generates an acid upon exposure, and the solubility in a developer changes due to the action of the acid. The resist composition contains a compound (hereinafter also referred to as "compound C") containing a cation (C0) represented by general formula (c0). Compound (C) may be a substrate component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer changes under the action of acid. Compound (C) may be an acid generator component (B) (hereinafter also referred to as "component (B)") that generates acid upon exposure. Compound (C) may be an acid diffusion controller component (D) (hereinafter also referred to as "component (D)") that traps the acid generated upon exposure (i.e., controls the diffusion of the acid).

[0029] The resist composition of this embodiment has the acid generating ability to generate an acid upon exposure, and either the component (A) or the component (B) may generate an acid upon exposure. Specifically, the resist composition of this embodiment comprises: (1) The component (B) may be contained as a component that generates acid upon exposure, (2) The component (A) may be a component that generates an acid upon exposure to light, (3) The component (A) is a component that generates an acid upon exposure, and may also contain the component (B). That is, in the cases of (2) and (3) above, the component (A) is a "base component that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid." When the component (A) is a base component that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, the component (A1) described below is preferably a polymeric compound that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid. As such a polymeric compound, a resin having a structural unit that generates acid upon exposure can be used. As the structural unit that generates acid upon exposure, known compounds can be used.

[0030] When a resist film is formed using the resist composition of this embodiment and then subjected to selective exposure, an acid is generated from component (A) or component (B) in the exposed areas of the resist film, and the solubility of component (A) in a developer changes due to the action of the acid, whereas the solubility of component (A) in a developer does not change in the unexposed areas of the resist film, resulting in a difference in solubility in a developer between the exposed and unexposed areas. Therefore, when the resist film is developed, if the resist composition is positive, the exposed areas of the resist film are dissolved and removed, forming a positive resist pattern, whereas if the resist composition is negative, the unexposed areas of the resist film are dissolved and removed, forming a negative resist pattern.

[0031] In this specification, a resist composition that dissolves and removes exposed portions of a resist film to form a positive resist pattern is referred to as a positive resist composition, and a resist composition that dissolves and removes unexposed portions of a resist film to form a negative resist pattern is referred to as a negative resist composition. The resist composition of this embodiment may be a positive resist composition or a negative resist composition. Furthermore, the resist composition of this embodiment may be for use in an alkaline development process in which an alkaline developer is used for the development treatment during resist pattern formation, or may be for use in a solvent development process in which a developer containing an organic solvent (organic developer) is used for the development treatment.

[0032] <Compound (C) containing cation (C0)> The resist composition of this embodiment contains a compound (C) containing a cation (C0) represented by the following general formula (c0).

[0033] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.]

[0034] In the formula (c0), X 01 is an electron-withdrawing group. Examples of electron-withdrawing groups include an acyl group, a methanesulfonyl group (mesyl group), a halogen atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, and a thiocarbonyl group. Examples of the halogen atom in the halogenated alkyl group, halogenated alkoxy group, halogenated aryloxy group, halogenated alkylamino group, and halogenated alkylthio group include a fluorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred. The alkyl group in the halogenated alkyl group, halogenated alkoxy group, halogenated alkylamino group, halogenated alkylthio group, dialkylphosphono group, and alkylsulfonyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 or 2 carbon atoms. Of these, the electron-withdrawing group is preferably a fluorine atom or a fluorinated alkyl group, more preferably a fluorine atom or a fluorinated alkyl group having 1 to 3 carbon atoms, and even more preferably a fluorine atom or a trifluoromethyl group. Specific examples of the electron-withdrawing group are shown below.

[0035] [ka]

[0036] In the formula (c0), X 02 is X 01 is an electron-withdrawing group different from X 02 The electron-withdrawing group in 01 The electron-withdrawing groups in X may be the same as those listed above. 02 The electron-withdrawing group of X 01 The electron-withdrawing group X is different from the electron-withdrawing group X. 01 and X02 and are not the same electron-withdrawing group.

[0037] X 01 and X 02 Examples of the combination of X include a combination of a halogen atom and a halogenated alkyl group, a combination of a halogen atom and a methanesulfonyl group, a combination of a halogenated alkyl group and a methanesulfonyl group, a combination of a halogen atom and a cyano group, and a combination of a halogenated alkyl group and a cyano group. 01 and X 02 A preferred combination is a combination of a fluorine atom and a fluorinated alkyl group.

[0038] In the formula (c0), nx1 and nx2 each independently represent an integer of 1 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same as or different from each other. nx1 and nx2 are preferably integers of 1 to 3, more preferably 1 or 2, and even more preferably 1. nx1 and nx2 are preferably 1 from the viewpoint of preventing the hydrophobicity from becoming too high.

[0039] The cation (C0) is attached to the phenyl group bonded to the sulfur atom of the dibenzothiophene skeleton by X. 01 and X 02 By containing two or more electron-withdrawing groups represented by the formula (I), the symmetry of the electron density of the phenyl group is disrupted. In the cation (C0), the phenyl group bonded to the sulfur atom of the dibenzothiophene skeleton has a high degree of rotational freedom. It is believed that disruption of the electron density of this phenyl group with a high degree of rotational freedom improves solubility in solvents. Therefore, the compound (C) containing the cation (C0) has improved solubility in organic solvents used to prepare resist compositions. Furthermore, the cation (C0) decomposed by exposure has improved solubility in developing solutions. As a result, defects are reduced.

[0040] X 01and X 02 The bonding position of X in the phenyl group is not particularly limited. From the viewpoint of disturbing the symmetry of the electron density in the phenyl group, 01 and X 02 is preferably bonded to the phenyl group so that the balance of electron-withdrawing groups in the phenyl group is asymmetric. For example, it is preferable that the same electron-withdrawing group is not bonded to the two ortho positions of the phenyl group. It is also preferable that the same electron-withdrawing group is not bonded to the two meta positions of the phenyl group. 01 and X 02 Examples of combinations of bonding positions to the phenyl group include a combination of meta and meta positions, a combination of para and meta positions, a combination of meta and ortho positions, and a combination of ortho and para positions. Examples of combinations of meta and ortho positions include a combination of 1 and 2 positions, a combination of 1 and 4 positions, a combination of 2 and 5 positions, and a combination of 4 and 5 positions. Examples of combinations of meta and ortho positions include a combination of 1 and 4 positions, or a combination of 2 and 5 positions.

[0041] In the formula (c0), R 01 is an electron-donating group. 01 The electron-donating group in is not particularly limited. Examples of the electron-donating group include an alkyl group and an alkoxy group. The alkyl group and alkoxy group preferably have 1 to 5 carbon atoms, more preferably have 1 to 3 carbon atoms, and even more preferably have 1 or 2 carbon atoms. Specific examples of the electron-donating group include a methyl group, an ethyl group, a tert-butyl group, an n-butyl group, and a methoxy group.

[0042] In (c0), n1 is an integer of 0 to 3. n1 is preferably 0 to 2, more preferably 0 or 1. When n1 is 2 or more, a plurality of R 01 may be the same as or different from each other. nx1+nx2+n1≦5.

[0043] In the formula (c0), R 02 and R 03 are each independently a substituent. 02 and R03 The substituent in R may be an electron-withdrawing group or an electron-donating group. 02 and R 03 Examples of the substituent in include the same groups as those exemplified above as the electron-withdrawing group and electron-donating group.

[0044] In the formula (c0), n2 and n3 each independently represent an integer of 0 to 4. n2 and n3 are preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and even more preferably 0 or 1. When n2 is 2 or greater, a plurality of R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.

[0045] Specific examples of the cation (C0) are shown below, but are not limited to these.

[0046] [ka]

[0047] [ka]

[0048] [First embodiment] The resist composition of the first embodiment contains a compound (C) as the component (B). The resist composition of the first embodiment contains a component (A) that generates an acid upon exposure and whose solubility in a developer changes due to the action of the acid, and an acid generator component (B) that generates an acid upon exposure. The acid generator component (B) includes a compound represented by the following general formula (b0):

[0049] [ka] [In the formula, M b+ is the cation (C0). - is the counter anion.

[0050] <Component (A)> In the resist composition of this embodiment, the component (A) preferably contains a resin component (A1) (hereinafter also referred to as "component (A1)") whose solubility in a developer changes under the action of acid. By using the component (A1), the polarity of the base component changes before and after exposure, and therefore good development contrast can be obtained not only in an alkaline development process but also in a solvent development process. As the component (A), at least the component (A1) is used, and other polymeric compounds and / or low molecular weight compounds may be used in combination with the component (A1).

[0051] When an alkaline development process is applied, the base component containing the component (A1) is poorly soluble in an alkaline developer before exposure, but when an acid is generated from the component (B) upon exposure, for example, the acid increases the polarity and the solubility in the alkaline developer. Therefore, in forming a resist pattern, when a resist film obtained by applying the resist composition to a support is selectively exposed to light, the exposed areas of the resist film change from being poorly soluble in an alkaline developer to being soluble, while the unexposed areas of the resist film remain poorly soluble in alkali, and therefore a positive resist pattern is formed by alkaline development.

[0052] On the other hand, when a solvent development process is applied, the base component containing the component (A1) is highly soluble in organic developers before exposure, but when, for example, an acid is generated from the component (B) upon exposure, the acid increases the polarity and reduces the solubility in organic developers. Therefore, in forming a resist pattern, when a resist film obtained by applying the resist composition to a support is selectively exposed to light, the exposed areas of the resist film change from soluble to sparingly soluble in organic developers, while the unexposed areas of the resist film remain soluble. Therefore, by developing with an organic developer, a contrast can be created between the exposed and unexposed areas, and a negative resist pattern can be formed.

[0053] In the resist composition of this embodiment, the component (A) may use either a single type of compound, or a combination of two or more types of compounds.

[0054] About component (A1) The component (A1) is a resin component whose solubility in a developer changes under the action of an acid. The component (A1) preferably has a structural unit (a1) that includes an acid-decomposable group whose polarity increases upon the action of an acid. The component (A1) may contain other structural units in addition to the structural unit (a1), as necessary.

[0055] <Constituent unit (a1)> The structural unit (a1) is a structural unit that contains an acid-decomposable group whose polarity increases upon the action of an acid.

[0056] Examples of the acid-dissociable group include those that have been proposed as acid-dissociable groups for base resins used in chemically amplified resist compositions. Specific examples of acid-dissociable groups that have been proposed for use in base resins for chemically amplified resist compositions include the "acetal-type acid-dissociable groups," "tertiary alkyl ester-type acid-dissociable groups," and "tertiary alkyloxycarbonyl acid-dissociable groups," which are described below.

[0057] Acetal type acid dissociable group: Among the polar groups, examples of the acid-dissociable group that protects a carboxy group or a hydroxyl group include acid-dissociable groups represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as "acetal-type acid-dissociable groups").

[0058] [ka] [In the formula, Ra' 1 , Ra' 2 is a hydrogen atom or an alkyl group. 3 is a hydrocarbon group, and Ra' 3 Ra' 1 , Ra' 2may be bonded to any one of the following to form a ring.]

[0059] In formula (a1-r-1), Ra' 1 and Ra' 2 At least one of these is preferably a hydrogen atom, and both are more preferably hydrogen atoms. Ra' 1 or Ra' 2 When is an alkyl group, examples of the alkyl group include the same alkyl groups as those exemplified as the substituent that may be bonded to the carbon atom at the α-position in the description of the α-substituted acrylic acid ester above, and an alkyl group having 1 to 5 carbon atoms is preferred. Specific examples include linear or branched alkyl groups. More specific examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl groups, with methyl and ethyl groups being more preferred, and methyl being particularly preferred.

[0060] In formula (a1-r-1), Ra' 3 Examples of the hydrocarbon group include a linear or branched alkyl group, and 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. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Of these, a methyl group, an ethyl group, or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

[0061] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, with an isopropyl group being preferred.

[0062] Ra' 3When 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. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0063] Ra' 3 When the cyclic hydrocarbon group is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further 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 heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in the aromatic heterocycle include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of the aromatic heterocycle include pyridine rings and thiophene rings. Ra' 3Specific examples of the aromatic hydrocarbon group in the formula (I) include a group (aryl group or heteroaryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle; a group in which one hydrogen atom has been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle has been substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group). The alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0064] Ra' 3 The cyclic hydrocarbon group in may have a substituent. Examples of the substituent include -R P1 , -R P2 -OR P1 , -R P2 -CO-R P1 , -R P2 -CO-OR P1 , -R P2 -O-CO-R P1 , -R P2 -OH, -R P2 -CN or -R P2 -COOH (hereinafter these substituents are collectively referred to as "Ra x5 ") are also examples. where R P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent alicyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. P2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent alicyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. P1 and R P2Some or all of the hydrogen atoms in the chain saturated hydrocarbon group, the alicyclic saturated hydrocarbon group, and the aromatic hydrocarbon group may be substituted with fluorine atoms. The alicyclic hydrocarbon group may have one or more of the above-mentioned substituents, or may have one or more of each of multiple types of the above-mentioned substituents. Examples of the monovalent chain 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, and a decyl group. 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, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, and cyclododecyl group; and polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group, tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and adamantyl group. Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups in which one hydrogen atom has been removed from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, or phenanthrene.

[0065] Ra' 3 But Ra' 1 , Ra' 2 When the cyclic group is bonded to any of the above to form a ring, the cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

[0066] Tertiary alkyl ester-type acid-labile group: Among the 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 constituted by an alkyl group may be referred to as "tertiary alkyl ester-type acid-dissociable groups" hereinafter for convenience.

[0067] [ka] [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.

[0068] Ra' 4 Examples of the hydrocarbon group include a linear or branched alkyl group, a linear or cyclic alkenyl group, and a cyclic hydrocarbon group. Ra' 4 The linear or branched alkyl group and the cyclic hydrocarbon group (a monocyclic aliphatic hydrocarbon group, a polycyclic aliphatic hydrocarbon group, and an aromatic hydrocarbon group) in 3 The same can be mentioned. Ra' 4 The chain or cyclic alkenyl group in the formula (I) is preferably an alkenyl group having 2 to 10 carbon atoms. Ra' 5 , Ra' 6 The hydrocarbon group of Ra' 3 The same can be mentioned.

[0069] Ra' 5 and Ra' 6 and (a1-r2-3) are preferably substituted or unsubstituted by the alkyl group. On the other hand, Ra' 4 ~Ra' 6 When are not bonded to each other and are independent hydrocarbon groups, preferred examples include groups represented by the following general formula (a1-r2-4).

[0070] [ka] [In formula (a1-r2-1), Ra' 10 Ra' represents a linear or branched alkyl group having 1 to 12 carbon atoms, some of which may be substituted with a halogen atom or a heteroatom-containing group. 11 Ra' 10 represents a group that forms an aliphatic cyclic group together with the carbon atom to which Ya 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 in 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 cyclic aliphatic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms in the linear saturated hydrocarbon group and the cyclic aliphatic saturated hydrocarbon group may be substituted. 101 ~Ra 103 Two or more of these may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group which forms an aliphatic cyclic group together with Yaa. Ra 104 In formula (a1-r2-4), Ra' is an aromatic hydrocarbon group which may have a substituent. 12 and Ra' 13 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Some or all of the hydrogen atoms in this chain saturated hydrocarbon group may be substituted. 14 is a hydrocarbon group which may have a substituent. * indicates a bond.]

[0071] In the above formula (a1-r2-1), Ra' 10 is a linear or branched alkyl group having 1 to 12 carbon atoms, some of which may be substituted with a halogen atom or a heteroatom-containing group.

[0072] Ra' 10The linear alkyl group in the formula (I) has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. Ra' 10 In the formula (I), the branched alkyl group is the above-mentioned Ra' 3 The same can be mentioned.

[0073] Ra' 10 The alkyl group in may be partially substituted with a halogen atom or a heteroatom-containing group. For example, some of the hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. Furthermore, some of the carbon atoms (e.g., methylene groups) constituting the alkyl group may be substituted with a heteroatom-containing group. Examples of heteroatoms include oxygen, sulfur, and nitrogen atoms. Examples of heteroatom-containing groups include (-O-), -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -S-, -S(=O)2-, and -S(=O)2-O-.

[0074] In formula (a1-r2-1), Ra' 11 (Ra' 10 The aliphatic cyclic group formed together with the carbon atom to which the carbon atom is bonded is represented by Ra' in formula (a1-r-1). 3 Among these, a monocyclic alicyclic hydrocarbon group is preferred, and specifically, a cyclopentyl group or a cyclohexyl group is more preferred, with a cyclopentyl group being even more preferred.

[0075] In the formula (a1-r2-2), the cyclic hydrocarbon group formed by Xa together with Ya includes Ra' in the formula (a1-r-1). 3 Examples of such groups include groups in which one or more hydrogen atoms have been further removed from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) shown above. The cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. The substituent may be any of the above-mentioned Ra' 3Examples of the substituents include the same as those that the cyclic hydrocarbon group in the above may have. In formula (a1-r2-2), Ra 101 ~Ra 103 In the formula (I), examples of the monovalent chain 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, and a decyl group. Ra 101 ~Ra 103 In the formula (I), 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, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, and cyclododecyl group; and polycyclic aliphatic saturated hydrocarbon groups such as a bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.02,6]decanyl group, tricyclo[3.3.1.13,7]decanyl group, tetracyclo[6.2.1.13,6.02,7]dodecanyl group, and adamantyl group. Ra 101 ~Ra 103 Among these, from the viewpoint of ease of synthesis, a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms is preferred, and among these, a hydrogen atom, a methyl group, or an ethyl group is more preferred, with a hydrogen atom being particularly preferred.

[0076] The above Ra 101 ~Ra 103 Examples of the substituents that the chain saturated hydrocarbon group or the aliphatic cyclic saturated hydrocarbon group represented by the formula: x5 The same groups as those shown below can be mentioned.

[0077] Ra 101 ~Ra 103Examples of the group containing a carbon-carbon double bond formed by two or more of the above being bonded to each other to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methylcyclohexenyl group, a cyclopentylidene-ethenyl group, a cyclohexylidene-ethenyl group, etc. Among these, from the viewpoint of ease of synthesis, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylidene-ethenyl group are preferred.

[0078] In formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is Ra' in formula (a1-r-1). 3 The groups mentioned above as the aliphatic hydrocarbon group are preferably monocyclic or polycyclic groups. In formula (a1-r2-3), Ra 104 Examples of the aromatic hydrocarbon group in the formula include a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. 104 is preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from benzene or naphthalene, and most preferably a group in which one or more hydrogen atoms have been removed from benzene.

[0079] Ra in formula (a1-r2-3) 104 Examples of the substituent that may be possessed by include 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, or a butoxy group), and an alkyloxycarbonyl group.

[0080] In formula (a1-r2-4), Ra' 12 and Ra' 13 are each independently a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. 12 and Ra' 13In the formula, the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms includes the above-mentioned Ra 101 ~Ra 103 Examples include the same monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms as in the above. Some or all of the hydrogen atoms in this chain saturated hydrocarbon group may be substituted. Ra' 12 and Ra' 13 Among these, a hydrogen atom or an alkyl group having 1 to 5 carbon atoms is preferred, an alkyl group having 1 to 5 carbon atoms is more preferred, a methyl group or an ethyl group is even more preferred, and a methyl group is particularly preferred. The above Ra' 12 and Ra' 13 When the chain saturated hydrocarbon group represented by the formula: is substituted, examples of the substituent include the above-mentioned Ra x5 The same groups as those shown below can be mentioned.

[0081] In formula (a1-r2-4), Ra' 14 Ra' is a hydrocarbon group which may have a substituent. 14 The hydrocarbon group in the formula (I) includes a linear or branched alkyl group, or a cyclic hydrocarbon group.

[0082] Ra' 14 The linear alkyl group in the formula (I) preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific 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 preferred, and a methyl group or an ethyl group is more preferred.

[0083] Ra' 14 The branched alkyl group in the formula (I) preferably has 3 to 10 carbon atoms, more preferably 3 to 5. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, with an isopropyl group being preferred.

[0084] Ra'14 When 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. The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The aliphatic hydrocarbon group that is a polycyclic group is preferably a group in which one hydrogen atom has been removed from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0085] Ra' 14 As the aromatic hydrocarbon group in 104 Among them, the aromatic hydrocarbon groups Ra' are the same as those in 14 is preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from naphthalene or anthracene, and most preferably a group in which one or more hydrogen atoms have been removed from naphthalene. Ra' 14 Examples of the substituent that may be possessed by Ra include 104 Examples of the substituents include the same as those that may be possessed by the group.

[0086] Ra' in formula (a1-r2-4) 14 When is a naphthyl group, the position at which it is bonded to the tertiary carbon atom in the formula (a1-r2-4) may be either the 1st or 2nd position of the naphthyl group. Ra' in formula (a1-r2-4) 14When is an anthryl group, the position at which it is bonded to the tertiary carbon atom in the formula (a1-r2-4) may be any one of the 1st, 2nd, or 9th position of the anthryl group.

[0087] Specific examples of the group represented by the formula (a1-r2-1) are listed below.

[0088] [ka]

[0089] [ka]

[0090] [ka]

[0091] Specific examples of the group represented by the formula (a1-r2-2) are listed below.

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] Specific examples of the group represented by the formula (a1-r2-3) are listed below.

[0096] [ka]

[0097] Specific examples of the group represented by the formula (a1-r2-4) are listed below.

[0098] [ka]

[0099] Tertiary alkyloxycarbonyl acid dissociating group: Among the polar groups, examples of the acid-dissociable group that protects the hydroxyl group include acid-dissociable groups represented by the following general formula (a1-r-3) (hereinafter, for convenience, may be referred to as "tertiary alkyloxycarbonyl acid-dissociable group").

[0100] [ka] [In the formula, Ra' 7 ~Ra' 9 are each alkyl groups.

[0101] In formula (a1-r-3), Ra' 7 ~Ra' 9 are each preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms. The total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0102] Examples of the structural unit (a1) include 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; a structural unit derived from acrylamide; a structural unit derived from hydroxystyrene or a hydroxystyrene derivative in which at least some of the hydrogen atoms in the hydroxyl groups are protected with a substituent containing the above-mentioned acid-decomposable group; and a structural unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative in which at least some of the hydrogen atoms in -C(═O)-OH are protected with a substituent containing the above-mentioned acid-decomposable group.

[0103] Of the above, preferred structural units (a1) are structural units derived from acrylate esters in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent. Preferred specific examples of the structural unit (a1) include structural units represented by the following general formula (a1-1) or (a1-2).

[0104] [ka] [wherein 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. 1 is a divalent hydrocarbon group which may have an ether bond. a1 is an integer between 0 and 2. 1 is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-2). 1 is n a2 + is a monovalent hydrocarbon group, n a2 is an integer between 1 and 3, and Ra 2 is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

[0105] In the formula (a1-1), the alkyl group of 1 to 5 carbon atoms represented by R is preferably a linear or branched alkyl group of 1 to 5 carbon atoms, and specific examples thereof 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, and a neopentyl group. The halogenated alkyl group of 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group of 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferred. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and is most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.

[0106] In the formula (a1-1), Va 1The divalent hydrocarbon group in may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0107] Va 1 The aliphatic hydrocarbon group as the divalent hydrocarbon group in may be saturated or unsaturated, and is usually preferably saturated. More specifically, the aliphatic hydrocarbon group may be a straight-chain or branched-chain aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in its structure.

[0108] The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred, and specific examples include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group, and specific examples thereof include alkyl alkylene groups such as alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0109] Examples of the aliphatic hydrocarbon group containing a ring in its structure include an alicyclic hydrocarbon group (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group is interposed in the middle of a straight-chain or branched-chain aliphatic hydrocarbon group. Examples of the straight-chain or branched-chain aliphatic hydrocarbon group include the same as the straight-chain aliphatic hydrocarbon group or the branched-chain aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be polycyclic or monocyclic. A preferred monocyclic alicyclic hydrocarbon group is a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. A preferred polycyclic alicyclic hydrocarbon group is a group in which two hydrogen atoms have been removed from a polycycloalkane, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0110] Va 1 The aromatic hydrocarbon group as the divalent hydrocarbon group in the formula (I) 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, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12. However, this number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring contained in the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring (an arylene group); a group in which one hydrogen atom of a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring (an aryl group) has been substituted with an alkylene group (for example, a group in which one hydrogen atom has been further removed 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 (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0111] In the formula (a1-1), Ra 1 is an acid-dissociable group represented by the above formula (a1-r-1) or (a1-r-2).

[0112] In the formula (a1-2), Wa 1 n in a2The monovalent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group refers to a hydrocarbon group that does not have aromaticity and may be saturated or unsaturated, but is usually preferably saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, aliphatic hydrocarbon groups containing a ring in their structure, and groups that combine linear or branched aliphatic hydrocarbon groups with aliphatic hydrocarbon groups containing a ring in their structure. The n a2 The +1 valence is preferably 2 to 4, more preferably 2 or 3.

[0113] In the formula (a1-2), Ra 2 is an acid-dissociable group represented by the above general formula (a1-r-1) or (a1-r-3).

[0114] Specific examples of the structural unit represented by formula (a1-1) are shown below. In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0115] [ka]

[0116] [ka]

[0117] [ka]

[0118] [ka]

[0119] [ka]

[0120] [ka]

[0121] [ka]

[0122] [ka]

[0123] The structural unit (a1) contained in the component (A1) may be of one type, or may be of two or more types. As the structural unit (a1), a structural unit represented by the above formula (a1-1) is more preferred, as it is more likely to further improve the properties (sensitivity, shape, etc.) in lithography using electron beams or EUV. Among these, as the structural unit (a1), those containing a structural unit represented by the following general formula (a1-1-1) are particularly preferred.

[0124] [ka] [In the formula, Ra 1 " is an acid-dissociable group represented by general formula (a1-r2-1), (a1-r2-3), or (a1-r2-4).

[0125] In the formula (a1-1-1), R, Va 1 and n a1 represents R and Va in the formula (a1-1). 1 and n a1 is the same as: The acid-dissociable group represented by general formula (a1-r2-1), (a1-r2-3), or (a1-r2-4) is as described above. Among these, it is preferable to select an acid-dissociable group that is a cyclic group, since this is suitable for use with EB or EUV and can enhance reactivity.

[0126] In the formula (a1-1-1), Ra 1Among the above, " is preferably an acid-dissociable group represented by general formula (a1-r2-1).

[0127] The proportion of the structural unit (a1) in the component (A1) is preferably 5 to 80 mol %, more preferably 10 to 75 mol %, even more preferably 30 to 70 mol %, and particularly preferably 40 to 70 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). By ensuring that the proportion of the structural unit (a1) is at least as large as the lower limit of the aforementioned preferred range, lithography properties such as sensitivity, resolution, and roughness can be improved. On the other hand, by ensuring that the proportion is at most the upper limit of the aforementioned preferred range, a balance with other structural units can be achieved, resulting in various favorable lithography properties.

[0128] Other structural units The component (A1) may contain other structural units in addition to the structural unit (a1) described above, as necessary. Examples of other structural units include structural units (a2) containing a lactone-containing cyclic group, an -SO2- containing cyclic group, or a carbonate-containing cyclic group; structural units (a3) ​​containing a polar group-containing aliphatic hydrocarbon group; structural units (a4) containing an acid-non-dissociable aliphatic cyclic group; structural units (a10) represented by the general formula (a10-1) described below; structural units (st) derived from styrene or a styrene derivative; and structural units derived from hydroxystyrene or a hydroxystyrene derivative.

[0129] Regarding the structural unit (a2): In addition to the structural unit (a1), the component (A1) may further contain a structural unit (a2) containing a lactone-containing cyclic group, an —SO—-containing cyclic group, or a carbonate-containing cyclic group (provided that this does not apply to structural unit (a1)). The lactone-containing cyclic group, -SO2-containing cyclic group, or carbonate-containing cyclic group of the structural unit (a2) is effective in improving the adhesion of the resist film to the substrate when the component (A1) is used to form a resist film. Furthermore, the presence of the structural unit (a2) results in favorable lithography properties, for example, by appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development.

[0130] A "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -OC(=O)- in its ring skeleton. The lactone ring is counted as the first ring, and a group consisting of only a lactone ring is called a monocyclic group. If a group further contains other ring structures, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group. The lactone-containing cyclic group in the structural unit (a2) is not particularly limited and any suitable group can be used. Specific examples include groups represented by the following general formulae (a2-r-1) to (a2-r-7).

[0131] [ka] [In the formula, Ra' 21 are 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; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or an -SO2- containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (-O-) or a sulfur atom (-S-), an oxygen atom, or a sulfur atom; n' is an integer of 0 to 2, and m' is 0 or 1.

[0132] In the general formulas (a2-r-1) to (a2-r-7), Ra' 21The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific 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 a hexyl group. Among these, a methyl group or an ethyl group is preferred, and a methyl group is particularly preferred. Ra' 21 The alkoxy group in the formula (1) is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the alkoxy group in the formula (1) is preferably linear or branched. 21 Examples of the alkyl group include a group in which the alkyl groups mentioned above are linked to an oxygen atom (—O—). Ra' 21 The halogen atom in is preferably a fluorine atom. Ra' 21 The halogenated alkyl group in the formula Ra' is 21 Examples of the halogenated alkyl group include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferred, and a perfluoroalkyl group is particularly preferred.

[0133] Ra' 21 In -COOR" and -OC(=O)R", R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or an -SO2- containing cyclic group. The alkyl group in 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 is 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. Specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; and groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as a bicycloalkane, a tricycloalkane, or a tetracycloalkane. More specific examples include groups in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; and groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples of the lactone-containing cyclic group in R″ include the same groups as those represented by the general formulae (a2-r-1) to (a2-r-7) above. The carbonate-containing cyclic group in R″ is the same as the carbonate-containing cyclic group described below, and specific examples include groups represented by the general formulae (ax3-r-1) to (ax3-r-3). The -SO2-containing cyclic group in R'' is the same as the -SO2-containing cyclic group described below, and specific examples include groups represented by general formulae (a5-r-1) to (a5-r-4). Ra' 21 The hydroxyalkyl group in the formula (I) preferably has 1 to 6 carbon atoms, and specifically, the hydroxyalkyl group in the formula (I) is preferably a hydroxyalkyl group having 1 to 6 carbon atoms. 21 and a group in which at least one hydrogen atom of the alkyl group is substituted with a hydroxyl group.

[0134] Ra' 21 Among the above, each of the groups is preferably independently a hydrogen atom or a cyano group.

[0135] In the general formulae (a2-r-2), (a2-r-3), and (a2-r-5), the alkylene group having 1 to 5 carbon atoms for A" is preferably a straight-chain or branched-chain alkylene group, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include groups in which -O- or -S- is present at the terminal or between carbon atoms of the alkylene group, such as 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.

[0136] Specific examples of the groups represented by the general formulae (a2-r-1) to (a2-r-7) are listed below.

[0137] [ka]

[0138] [ka]

[0139] The term "-SO2-containing cyclic group" refers to a cyclic group containing a ring containing -SO2- in its ring skeleton, specifically a cyclic group in which the sulfur atom (S) in -SO2- forms part of the ring skeleton of the cyclic group. The ring containing -SO2- in the ring skeleton is counted as the first ring, and if it contains only that ring, it is called a monocyclic group. If it contains other ring structures, it is called a polycyclic group regardless of the structure. The -SO2- containing cyclic group may be a monocyclic group or a polycyclic group. The -SO2- containing cyclic group is preferably a cyclic group containing -O-SO2- in its ring skeleton, i.e., a cyclic group containing a sultone ring in which -OS- in -O-SO2- forms part of the ring skeleton. More specific examples of the —SO2—-containing cyclic group include groups represented by the following general formulae (a5-r-1) to (a5-r-4).

[0140] [ka] [In the formula, Ra' 51 are 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; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or an -SO2- containing cyclic group; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom, and n' is an integer of 0 to 2.

[0141] In the general formulae (a5-r-1) and (a5-r-2), A" is the same as A" in the general formulae (a2-r-2), (a2-r-3), and (a2-r-5). Ra' 51 The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in the general formulae (a2-r-1) to (a2-r-7) are each represented by Ra' 21 Examples of the above include those mentioned in the explanation of the above. Specific examples of the groups represented by general formulae (a5-r-1) to (a5-r-4) are listed below, in which "Ac" represents an acetyl group.

[0142] [ka]

[0143] [ka]

[0144] [ka]

[0145] The term "carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -OC(=O)-O- in its ring skeleton. The carbonate ring is counted as the first ring, and when there is only a carbonate ring, it is called a monocyclic group. When there is further ring structure, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group. The carbonate-containing cyclic group is not particularly limited and any one can be used. Specific examples include groups represented by the following general formulae (ax3-r-1) to (ax3-r-3).

[0146] [ka] [In the formula, Ra' x31 are 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; R" is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or an -SO2- containing cyclic group; A" 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; p' is an integer of 0 to 3, and q' is 0 or 1.

[0147] In the general formulae (ax3-r-2) to (ax3-r-3), A" is the same as A" in the general formulae (a2-r-2), (a2-r-3) and (a2-r-5). Ra' 31 The alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in the general formulae (a2-r-1) to (a2-r-7) are each represented by Ra' 21 Examples of the above include those mentioned in the explanation of the above. Specific examples of the groups represented by the general formulae (ax3-r-1) to (ax3-r-3) are listed below.

[0148] [ka]

[0149] Of the structural units (a2), structural units derived from acrylate esters in which the hydrogen atom bonded to the α-position carbon atom may be substituted with a substituent are particularly preferred. Such a structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

[0150] [ka] [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.] 21 is a single bond or a divalent linking group. 21 is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO- or -CONHCS-, where R' represents a hydrogen atom or a methyl group. 21 If -O-, Ya 21 does not become -CO-. Ra 21 is a lactone-containing cyclic group, a carbonate-containing cyclic group, or an —SO—-containing cyclic group.

[0151] In the formula (a2-1), R is the same as defined above. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is particularly preferred.

[0152] In the formula (a2-1), Ya 21 The divalent linking group in is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

[0153] Optionally substituted divalent hydrocarbon groups: Ya 21When is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0154] Ya 21 Aliphatic hydrocarbon groups in The aliphatic hydrocarbon group refers to a hydrocarbon group that does not have 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, and an aliphatic hydrocarbon group containing a ring in its structure.

[0155] Linear or branched aliphatic hydrocarbon groups The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred, and specific examples include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group, and specific examples thereof include alkyl alkylene groups such as alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0156] The linear or branched aliphatic hydrocarbon group may or may not have a substituent, such as a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms and substituted with a fluorine atom, or a carbonyl group.

[0157] Aliphatic hydrocarbon groups containing rings in the structure Examples of the aliphatic hydrocarbon group containing a ring in its structure include a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a heteroatom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a straight-chain or branched-chain aliphatic hydrocarbon group. Examples of the straight-chain or branched-chain aliphatic hydrocarbon group include the same as those described above. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms. The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0158] The cyclic aliphatic hydrocarbon group may or may not have a substituent, such as an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, or a carbonyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. 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. The halogen atom as the substituent is preferably a fluorine atom. Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group have been 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 heteroatom, and the heteroatom-containing substituent is preferably -O-, -C(=O)-O-, -S-, -S(=O)2-, or -S(=O)2-O-.

[0159] Ya 21 Aromatic hydrocarbon groups in The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The 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. However, this 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 heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in the aromatic heterocycle include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of the aromatic heterocycle include pyridine rings and thiophene rings. Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene groups or heteroarylene groups); groups in which two hydrogen atoms have been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and groups in which one hydrogen atom of a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) has been substituted with an alkylene group (e.g., groups in which one hydrogen atom has been further removed from the aryl group in an arylalkyl group such as a benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, or 2-naphthylethyl group). The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0160] The aromatic hydrocarbon group may have a hydrogen atom substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Examples of the alkoxy group, halogen atom and halogenated alkyl group as the substituent include those exemplified as the substituent substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

[0161] Divalent linking groups containing heteroatoms: Ya 21 is a divalent linking group containing a hetero atom, preferred examples of the linking group include -O-, -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=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-, and groups represented by the general formula -Y 21 -OY 22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 -or- Y 21 -S(=O)2-OY 22 -, 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. When the divalent linking group containing a hetero atom is -C(=O)-NH-, -C(=O)-NH-C(=O)-, -NH-, or -NH-C(=NH)-, the H may be substituted with a substituent such as an alkyl group, an acyl group, etc. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 5 carbon atoms. General formula-Y 21 -OY22 -, -Y 21 -O-, -Y 21 -C(=O)-O-, -C(=O)-OY 21 -, -[Y 21 -C(=O)-O] m” -Y 22 -, -Y 21 -OC(=O)-Y 22 -or- Y 21 -S(=O)2-OY 22 -Medium, 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 above-mentioned Ya 21 Examples of the divalent linking group include the same groups as those (divalent hydrocarbon groups which may have a substituent) mentioned in the description of the divalent linking group in the above. Y 21 As the alkyl group, a straight-chain aliphatic hydrocarbon group is preferred, a straight-chain alkylene group is more preferred, a straight-chain alkylene group having 1 to 5 carbon atoms is even more preferred, and a methylene group or ethylene group is particularly preferred. 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. Formula − [Y 21 -C(=O)-O] m” -Y 22 In the group represented by -, 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 group represented by the formula -[Y 21 -C(=O)-O] m” -Y 22 The group represented by - is a group represented by the formula -Y 21 -C(=O)-OY 22 Particularly preferred is a group represented by the formula -(CH2) a’ -C(=O)-O-(CH2) b’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, even 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, even more preferably 1 or 2, and most preferably 1.

[0162] Among the above, 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.

[0163] In the above formula (a2-1), Ra 21 is a lactone-containing cyclic group, an —SO 2 —-containing cyclic group, or a carbonate-containing cyclic group. Ra 21 Suitable examples of the lactone-containing cyclic group, the -SO2- containing cyclic group, and the carbonate-containing cyclic group in the formula (a2-r-1), (a2-r-7), (a5-r-1), (a5-r-4), and (ax3-r-1), respectively, are the groups represented by the general formulas (ax3-r-3). Among these, lactone-containing cyclic groups or -SO2- containing cyclic groups are preferred, groups represented by the general formula (a2-r-1), (a2-r-2), (a2-r-6) or (a5-r-1) are more preferred, and groups represented by the general formula (a2-r-2) or (a5-r-1) are even more preferred. Specifically, any of the groups represented by the chemical formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r-lc-6-1), (r-sl-1-1), and (r-sl-1-18) are preferred, any of the groups represented by the chemical formulas (r-lc-2-1) to (r-lc-2-18), and (r-sl-1-1) are more preferred, and any of the groups represented by the chemical formulas (r-lc-2-1), (r-lc-2-12), and (r-sl-1-1) are even more preferred.

[0164] The structural unit (a2) contained in the component (A1) may be of one type, or may be of two or more types. When the component (A1) contains the structural unit (a2), the proportion of the structural unit (a2) relative to the total (100 mol%) of all structural units constituting the component (A1) is preferably 5 to 60 mol%, more preferably 10 to 60 mol%, even more preferably 20 to 60 mol%, and particularly preferably 30 to 60 mol%. When the proportion of the structural unit (a2) is at least as great as the preferred lower limit, the effects achieved by including the structural unit (a2) can be fully obtained due to the effects described above. When the proportion of the structural unit (a2) is at most the upper limit, a balance with other structural units can be achieved, and various lithography properties become favorable.

[0165] Regarding the structural unit (a3): In addition to the structural unit (a1), the component (A1) may further include a structural unit (a3) ​​(excluding those corresponding to the structural unit (a1) or the structural unit (a2)) that contains a polar group-containing aliphatic hydrocarbon group. The inclusion of the structural unit (a3) ​​in the component (A1) enhances the hydrophilicity of the component (A), contributing to improved resolution. Furthermore, the acid diffusion length can be appropriately adjusted.

[0166] Examples of the polar group include a hydroxyl group, a cyano group, a carboxyl group, and a hydroxyalkyl group in which some of the hydrogen atoms of an alkyl group have been substituted with fluorine atoms, with a hydroxyl group being particularly preferred. Examples of aliphatic hydrocarbon groups include linear or branched hydrocarbon groups (preferably alkylene groups) having 1 to 10 carbon atoms, and cyclic aliphatic hydrocarbon groups (cyclic groups). The cyclic group may be a monocyclic group or a polycyclic group, and can be appropriately selected from the many groups proposed for use in resins for resist compositions for ArF excimer lasers.

[0167] When the cyclic group is a monocyclic group, it more preferably has 3 to 10 carbon atoms. Among these, structural units derived from acrylate esters containing an aliphatic monocyclic group containing a hydroxyl group, a cyano group, a carboxy group, or a hydroxyalkyl group in which some of the alkyl group's hydrogen atoms are substituted with fluorine atoms are more preferred. Examples of such monocyclic groups include groups in which two or more hydrogen atoms have been removed from a monocycloalkane. Specific examples include groups in which two or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane, cyclohexane, or cyclooctane. Among these monocyclic groups, groups in which two or more hydrogen atoms have been removed from cyclopentane and groups in which two or more hydrogen atoms have been removed from cyclohexane are industrially preferred.

[0168] When the cyclic group is a polycyclic group, the polycyclic group preferably has 7 to 30 carbon atoms. Among these, structural units derived from acrylate esters containing an aliphatic polycyclic group containing a hydroxyl group, a cyano group, a carboxy group, or a hydroxyalkyl group in which some of the alkyl group's hydrogen atoms are substituted with fluorine atoms are more preferred. Examples of such polycyclic groups include groups in which two or more hydrogen atoms have been removed from bicycloalkanes, tricycloalkanes, tetracycloalkanes, etc. Specific examples include groups in which two or more hydrogen atoms have been removed from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane are industrially preferred.

[0169] There are no particular limitations on the structural unit (a3), and any structural unit can be used as long as it contains a polar group-containing aliphatic hydrocarbon group. As the structural unit (a3), 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, and which contains a polar group-containing aliphatic hydrocarbon group is preferred. When the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, the structural unit (a3) ​​is preferably a structural unit derived from a hydroxyethyl ester of acrylic acid. Furthermore, when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a polycyclic group, preferred examples of the structural unit (a3) ​​include structural units represented by the following formulas (a3-1), (a3-2), and (a3-3); and when the hydrocarbon group is a monocyclic group, preferred examples of the structural unit (a3) ​​include structural units represented by formula (a3-4).

[0170] [ka] [In the formula, R is the same as defined above, j is an integer of 1 to 3, k is an integer of 1 to 3, t' is an integer of 1 to 3, l is an integer of 0 to 5, and s is an integer of 1 to 3.]

[0171] In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, the hydroxyl groups are preferably bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, the hydroxyl group is preferably bonded to the 3rd position of the adamantyl group. j is preferably 1, and it is particularly preferred that the hydroxyl group is bonded to the 3-position of the adamantyl group.

[0172] In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5- or 6-position of the norbornyl group.

[0173] In formula (a3-3), t' is preferably 1. l is preferably 1. s is preferably 1. In these, a 2-norbornyl group or a 3-norbornyl group is preferably bonded to the terminal of the carboxyl group of the acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5- or 6-position of the norbornyl group.

[0174] In formula (a3-4), t' is preferably 1 or 2. l is preferably 0 or 1. s is preferably 1. The fluorinated alkyl alcohol is preferably bonded to the 3- or 5-position of the cyclohexyl group.

[0175] The structural unit (a3) ​​contained in the component (A1) may be of one type, or may be of two or more types. When the component (A1) contains the structural unit (a3), the proportion of the structural unit (a3) ​​relative to the total (100 mol%) of all structural units constituting the component (A1) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and even more preferably 5 to 20 mol%. By ensuring that the proportion of the structural unit (a3) ​​is at least as great as the preferred lower limit, the effects described above can be fully achieved by including the structural unit (a3). By ensuring that the proportion of the structural unit (a3) ​​is at most the preferred upper limit, a balance with other structural units can be achieved, and various lithography properties can be improved.

[0176] Regarding the structural unit (a4): In addition to the structural unit (a1), the component (A1) may further include a structural unit (a4) that contains an acid-non-dissociable aliphatic cyclic group. By including the structural unit (a4) in the component (A1), the dry etching resistance of the formed resist pattern is improved. Additionally, the hydrophobicity of the component (A) is enhanced. The improved hydrophobicity contributes to improvements in resolution, resist pattern shape, and the like, particularly in solvent development processes. The “acid-non-dissociable cyclic group” within the structural unit (a4) is a cyclic group that, when acid is generated in the resist composition upon exposure (for example, when acid is generated from a structural unit that generates acid upon exposure or from the component (B)), does not dissociate even when acted upon by the acid, and remains intact within the structural unit.

[0177] The structural unit (a4) is preferably, for example, a structural unit derived from an acrylate ester that contains an acid-non-dissociable aliphatic cyclic group. The cyclic group can be any of the many conventionally known resin components used in resist compositions for ArF excimer lasers, KrF excimer lasers (preferably ArF excimer lasers), and the like. The cyclic group is preferably at least one selected from the group consisting of a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group, in view of industrial availability, etc. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent. Specific examples of the structural unit (a4) include structural units represented by the following general formulas (a4-1) to (a4-7).

[0178] [ka] [In the formula, R α is the same as above.]

[0179] The structural unit (a4) contained in the component (A1) may be of one type, or may be of two or more types. When the component (A1) contains the structural unit (a4), the proportion of the structural unit (a4) relative to the total (100 mol %) of all structural units constituting the component (A1) is preferably 1 to 40 mol %, and more preferably 5 to 20 mol %. By ensuring that the proportion of the structural unit (a4) is at least as large as the preferred lower limit, the effects of including the structural unit (a4) can be fully achieved, while by ensuring that the proportion is at most the preferred upper limit, it becomes easier to achieve a balance with other structural units.

[0180] Regarding the structural unit (a10): The structural unit (a10) is a structural unit represented by the following general formula (a10-1).

[0181] [ka] [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.] x1 is a single bond or a divalent linking group. x1 is an aromatic hydrocarbon group which may have a substituent. ax1 is an integer greater than or equal to 1.]

[0182] In the formula (a10-1), 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 is the same as R in the formula (a0-1-1).

[0183] In the formula (a10-1), Ya x1 is a single bond or a divalent linking group. In the above chemical formula, Ya x1 The divalent linking group in is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom. x1 As the divalent linking group in the formula (a2-1), 21 Examples of the divalent linking group include the same as those exemplified above. Among them, Ya x1 is preferably a single bond, an ester bond [-C(=O)-O-, -OC(=O)-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof, and more preferably a single bond or an ester bond [-C(=O)-O-, -OC(=O)-].

[0184] In the formula (a10-1), Wa x1 is an aromatic hydrocarbon group which may have a substituent. Wa x1 The aromatic hydrocarbon group in the formula (n) is an aromatic ring which may have a substituent. ax14n+1) hydrogen atoms are removed. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, even 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 heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of aromatic heterocycles include pyridine rings and thiophene rings. Wa x1 The aromatic hydrocarbon group in the formula (n) may be selected from aromatic compounds containing an aromatic ring which may have two or more substituents (e.g., biphenyl, fluorene, etc.). ax1 +1) hydrogen atoms may also be removed. Among them, Wa x1 As examples, benzene, naphthalene, anthracene, or biphenyl (n ax1 A group in which (n +1) hydrogen atoms have been removed from benzene or naphthalene is preferred. ax1 A group obtained by removing (n +1) hydrogen atoms from benzene is more preferred. ax1 A group in which +1) hydrogen atoms have been removed is more preferred.

[0185] 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, and a halogenated alkyl group. Examples of the alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent include Ya x1 Examples of the substituent include the same as those exemplified as the substituent of the cyclic aliphatic hydrocarbon group in Wa. 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, further preferably an ethyl group or a methyl group, and particularly preferably a methyl group.x1 The aromatic hydrocarbon group in the formula (I) preferably does not have a substituent.

[0186] 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, further preferably 1, 2 or 3, and particularly preferably 1 or 2.

[0187] Specific examples of the structural unit (a10) represented by the formula (a10-1) are shown below. In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0188] [ka]

[0189] [ka]

[0190] [ka]

[0191] The structural unit (a10) contained in the component (A1) may be of one type, or may be of two or more types. When the component (A1) contains the structural unit (a10), the proportion of the structural unit (a10) in the component (A1) is preferably 10 to 80 mol %, more preferably 20 to 70 mol %, even more preferably 30 to 60 mol %, and particularly preferably 30 to 50 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). When the proportion of the structural unit (a10) is at least as large as the aforementioned preferable lower limit, sensitivity is likely to be further improved.When the proportion of the structural unit (a10) is no more than the aforementioned preferable upper limit, it is easier to achieve a balance with the other structural units.

[0192] Regarding the structural units (st): The structural unit (st) is a structural unit derived from styrene or a styrene derivative. A "structural unit derived from styrene" refers to a structural unit formed by cleavage of the ethylenic double bond of styrene. A "structural unit derived from a styrene derivative" refers to a structural unit formed by cleavage of the ethylenic double bond of a styrene derivative (however, this does not include those that fall under the category of structural unit (a10)).

[0193] The term "styrene derivative" refers to a compound in which at least some of the hydrogen atoms of styrene have been substituted with a substituent. Examples of styrene derivatives include those in which the hydrogen atom at the α-position of styrene has been substituted with a substituent, those in which one or more hydrogen atoms on the benzene ring of styrene have been substituted with a substituent, and those in which the hydrogen atom at the α-position of styrene and one or more hydrogen atoms on the benzene ring have been substituted with a substituent.

[0194] Examples of the substituent that substitutes the hydrogen atom at the α-position of styrene include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms. The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof 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, and a neopentyl group. 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 have been substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferred. The substituent substituting the hydrogen atom at the α-position of styrene is preferably an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or a fluorinated alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group from the viewpoint of industrial availability.

[0195] Examples of the substituent that substitutes the hydrogen atom on the benzene ring of styrene include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. 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. The halogen atom as the substituent is preferably a fluorine atom. Examples of the halogenated alkyl group as the substituent include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms. The substituent substituting the hydrogen atom on the benzene ring of styrene is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0196] The structural unit (st) is preferably a structural unit derived from styrene, or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms, more preferably a structural unit derived from styrene, or a structural unit derived from a styrene derivative in which the hydrogen atom at the α-position of styrene is substituted with a methyl group, and even more preferably a structural unit derived from styrene.

[0197] The structural unit (st) contained in the component (A1) may be of one type, or may be of two or more types. When the component (A1) contains the structural unit (st), the proportion of the structural unit (st) relative to the total (100 mol%) of all structural units constituting the component (A1) is preferably 1 to 30 mol%, and more preferably 3 to 20 mol%.

[0198] The component (A1) contained in the resist composition may use either a single type of compound, or a combination of two or more types of compounds. In the resist composition of this embodiment, the component (A1) can be a polymeric compound that has a repeating structure of the structural unit (a1), and preferably a polymeric compound that has a repeating structure of the structural unit (a1) and the structural unit (a10). Of the above, preferred examples of the component (A1) include polymeric compounds comprising a repeating structure of the structural unit (a1) and the structural unit (a10); and polymeric compounds comprising a repeating structure of the structural unit (a1), the structural unit (a10), and the structural unit (a3).

[0199] In polymeric compounds having a repeating structure of the structural unit (a1) and the structural unit (a10), the proportion of the structural unit (a1) relative to the total (100 mol%) of all structural units constituting the polymeric compound is preferably 10 to 90 mol%, more preferably 20 to 80 mol%, even more preferably 30 to 70 mol%, and particularly preferably 40 to 70 mol%. In polymeric compounds having a repeating structure of the structural unit (a1) and the structural unit (a10), the proportion of the structural unit (a10) relative to the total (100 mol%) of all structural units constituting the polymeric compound is preferably 10 to 90 mol%, more preferably 20 to 80 mol%, even more preferably 30 to 70 mol%, and particularly preferably 30 to 60 mol%.

[0200] In polymeric compounds having a repeating structure of the structural unit (a1), the structural unit (a10), and the structural unit (a3), the proportion of the structural unit (a1) relative to the total (100 mol%) of all structural units constituting the polymeric compound is preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 70 mol%, and particularly preferably 45 to 65 mol%. In polymeric compounds having a repeating structure of the structural unit (a1), the structural unit (a10), and the structural unit (a3), the proportion of the structural unit (a10) relative to the total (100 mol%) of all structural units constituting the polymeric compound is preferably 10 to 70 mol%, more preferably 20 to 60 mol%, even more preferably 20 to 50 mol%, and particularly preferably 25 to 45 mol%. Furthermore, in polymeric compounds having a repeating structure of the structural unit (a1), the structural unit (a10), and the structural unit (a3), the proportion of the structural unit (a3) ​​relative to the total (100 mol%) of all structural units constituting the polymeric compound is preferably 1 to 30 mol%, more preferably 5 to 25 mol%, even more preferably 5 to 20 mol%, and particularly preferably 5 to 15 mol%.

[0201] The molar ratio of the structural unit (a1) to the structural unit (a10) in the polymer compound (structural unit (a1):structural unit (a10)) is preferably 2:8 to 8:2, more preferably 3:7 to 7:3, and even more preferably 4:6 to 6:4.

[0202] The component (A1) can be produced by dissolving the monomers that derive the respective structural units in a polymerization solvent, and then adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate (e.g., V-601) to the solution and polymerizing the resulting mixture. Alternatively, the component (A1) can be produced by dissolving a monomer that derives the structural unit (a1) and, if necessary, a monomer that derives a structural unit other than the structural unit (a1) (for example, the structural unit (a10)) in a polymerization solvent, and then adding the above-mentioned radical polymerization initiator to the solution to carry out polymerization. During polymerization, a chain transfer agent such as HS-CH2-CH2-CH2-C(CF3)2-OH may be used in combination to introduce a -C(CF3)2-OH group to the terminal. Copolymers incorporating hydroxyalkyl groups in which some of the alkyl group's hydrogen atoms have been substituted with fluorine atoms are effective in reducing development defects and LER (line edge roughness: unevenness on the line sidewalls).

[0203] The weight average molecular weight (Mw) of the component (A1) (based on polystyrene standards measured by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and even more preferably 3,000 to 20,000. When the Mw of the component (A1) is less than or equal to the preferred upper limit of this range, the compound has sufficient solubility in a resist solvent for use as a resist, and when it is at least the preferred lower limit of this range, the compound exhibits good dry etching resistance and the cross-sectional shape of the resist pattern. The dispersity (Mw / Mn) of the component (A1) is not particularly limited, but is preferably from 1.0 to 4.0, more preferably from 1.0 to 3.0, and particularly preferably from 1.0 to 2.0, where Mn represents the number average molecular weight.

[0204] About ingredient (A2) The resist composition of this embodiment may also use, as the component (A), a base component (hereafter referred to as “component (A2)”) that does not fall under the category of the component (A1) and whose solubility in a developer changes upon the action of an acid. There are no particular restrictions on the component (A2), and it can be selected from the many conventional base components for chemically amplified resist compositions. The component (A2) may be a high molecular weight compound or a low molecular weight compound, and may be used alone or in combination of two or more types.

[0205] The proportion of the component (A1) within the component (A), relative to the total mass of the component (A), is preferably 25 mass% or more, more preferably 50 mass% or more, even more preferably 75 mass% or more, and may even be 100 mass%. When this proportion is 25 mass% or more, a resist pattern that is excellent in various lithography properties, such as high sensitivity, resolution, and improved roughness, is more likely to be formed.

[0206] The amount of the component (A) in the resist composition of this embodiment may be adjusted depending on factors such as the thickness of the resist film to be formed.

[0207] <Acid generator component (B)> The resist composition of this embodiment contains an acid generator component (B) that generates acid upon exposure. The component (B) includes a compound (B0) (hereinafter also referred to as "component (B0)") represented by the following general formula (b0):

[0208] <(B0) component> The component (B0) is a compound represented by the following general formula (b0).

[0209] [ka] [In the formula, M b+ is the cation (C0). - is the counter anion.

[0210] {cation part} In the general formula (b0), M b+ is the cation (C0).

[0211] {anion part} In the general formula (b0), Xb - is the counter anion. Xb - There are no particular restrictions on the anion moiety, and any of those proposed as an anion moiety in an acid generator for a chemically amplified resist composition can be used.

[0212] Xb -Examples of the anions include those represented by the following general formula (b-1-an), general formula (b-2-an), or general formula (b-3-an).

[0213] [ka] [In the formula, R 101 and R 104 ~R 108 R 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. 104 and R 105 R may be bonded to each other to form a ring structure. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 101 is a divalent linking group containing an oxygen atom or a single bond. 101 ~V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group. 101 ~L 102 are each independently a single bond or an oxygen atom. 103 ~L 105 are each independently a single bond, —CO—, or —SO—.

[0214] Anion represented by the formula (b-1-an) In formula (b-1-an), R 101 represents 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.

[0215] Optionally substituted cyclic groups: 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. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0216] R101 The aromatic hydrocarbon group in the formula (I) is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, the number of carbon atoms does not include the number of carbon atoms in the substituent. R 101 Specific examples of the aromatic ring contained in the aromatic hydrocarbon group in the above formula include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. R 101 Specific examples of the aromatic hydrocarbon group in the formula (I) include a group in which one hydrogen atom has been removed 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 has been substituted with an alkylene group (for example, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0217] R 101 The cyclic aliphatic hydrocarbon group in R may be an aliphatic hydrocarbon group containing a ring in the structure. 101 The cyclic aliphatic hydrocarbon group in the formula (I) preferably has 3 to 50 carbon atoms, more preferably 4 to 45 carbon atoms, and even more preferably 5 to 40 carbon atoms. Examples of aliphatic hydrocarbon groups that contain a ring in their structure include alicyclic hydrocarbon groups (groups in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is interposed in the middle of a straight-chain or branched-chain 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. The monocyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among these, the polycycloalkane is more preferably a polycycloalkane having a bridged ring polycyclic skeleton, such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; or a polycycloalkane having a fused ring polycyclic skeleton, such as a cyclic group having a steroid skeleton.

[0218] Among them, R 101 The cyclic aliphatic hydrocarbon group in is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, further preferably an adamantyl group or a norbornyl group, and particularly preferably an adamantyl group.

[0219] The linear aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. The linear aliphatic hydrocarbon group is preferably a linear alkylene group, and specific examples thereof include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, even more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. The branched aliphatic hydrocarbon group is preferably a branched alkylene group, and specific examples thereof include alkyl alkylene groups such as alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0220] Also, R 101 The cyclic hydrocarbon group in may contain a heteroatom, such as a heterocycle. Specific examples include lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7), -SO2- containing cyclic groups represented by the general formulae (a5-r-1) to (a5-r-4), and heterocyclic groups represented by the following chemical formulae (r-hr-1) to (r-hr-16). * in the formula represents Y in formula (b-1-an). 101 represents a bond bonded to

[0221] [ka]

[0222] R 101 Examples of the substituent in the cyclic group include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a 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 most preferably a methoxy group or an ethoxy group. Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred. Examples of halogenated alkyl groups as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms. The carbonyl group as a substituent is a group that substitutes a methylene group (-CH2-) that constitutes a cyclic hydrocarbon group.

[0223] R 101 The cyclic hydrocarbon group in may be a fused ring group containing a fused ring in which an aliphatic hydrocarbon ring and an aromatic ring are fused. Examples of the fused ring include a polycycloalkane having a polycyclic skeleton of a bridged ring system to which one or more aromatic rings are fused. Specific examples of the bridged ring system polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused ring group is preferably a group containing a fused ring in which two or three aromatic rings are fused to a bicycloalkane, and more preferably a group containing a fused ring in which two or three aromatic rings are fused to a bicyclo[2.2.2]octane. 101 Specific examples of the fused cyclic group in the formula (b-1-an) include those represented by the following formulas (r-br-1) to (r-br-2). In the formula, * represents Y in the formula (b-1-an). 101 represents a bond bonded to

[0224] [ka]

[0225] R 101 Examples of the substituent that the fused cyclic group in the formula (I) may 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, and an alicyclic hydrocarbon group. The alkyl group, alkoxy group, halogen atom, and halogenated alkyl group as the substituent of the fused cyclic group are the same as those described above in R 101 Examples of the substituents for the cyclic group in the formula (I) include the same as those listed above. Examples of the aromatic hydrocarbon group as the substituent of the fused ring group include a group in which one hydrogen atom has been removed from an aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), a group in which one hydrogen atom of the aromatic ring has been substituted with an alkylene group (for example, 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.), and heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-6). Examples of the alicyclic hydrocarbon group as a substituent of the fused cyclic group include groups in which one hydrogen atom has been removed from a monocycloalkane such as cyclopentane or cyclohexane; groups in which one hydrogen atom has been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane; lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7) above; —SO2- containing cyclic groups represented by the general formulae (a5-r-1) to (a5-r-4) above; and heterocyclic groups represented by the formulae (r-hr-7) to (r-hr-16) above.

[0226] R 101The cyclic hydrocarbon group in may be a group in which two or more aliphatic rings and / or aromatic rings are linked by a linear or branched aliphatic hydrocarbon group which may have a substituent. In the linear or branched aliphatic hydrocarbon group linking the alicyclic hydrocarbon groups, a methylene group (-CH-) constituting the aliphatic hydrocarbon chain may be substituted with a divalent group containing a heteroatom. Examples of the divalent group containing a heteroatom include (-O-), -C(=O)-O-, -OC(=O)-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH-, -S-, -S(=O)-, and -S(=O)-O-.

[0227] A chain alkyl group which may have a substituent: R 101 The chain alkyl group may be either a straight chain or a branched chain. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10. Specific examples include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0228] An optionally substituted chain alkenyl group: R 101 The chain alkenyl group may be either linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group. Of the chain alkenyl groups mentioned above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0229] R 101 Examples of the substituent in the chain alkyl or alkenyl group include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the above-mentioned R 101 Examples of the cyclic groups include the cyclic groups shown in the formula:

[0230] Among the above, R 101 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, the cyclic hydrocarbon group is preferably a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane; a lactone-containing cyclic group represented by each of the general formulae (a2-r-1) to (a2-r-7); or an -SO2- containing cyclic group represented by each of the general formulae (a5-r-1) to (a5-r-4), more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane or an -SO2- containing cyclic group represented by each of the general formulae (a5-r-1) to (a5-r-4), and even more preferably an adamantyl group or an -SO2- containing cyclic group represented by the general formula (a5-r-1).

[0231] When the cyclic hydrocarbon group has a substituent, the substituent is preferably a hydroxyl group.

[0232] In formula (b-1-an), Y 101 is a single bond or a divalent linking group containing an oxygen atom. Y 101 is a divalent linking group containing an oxygen atom, 101 may contain atoms other than oxygen atoms. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms. Examples of the divalent linking group containing an oxygen atom include non-hydrocarbon 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-); and combinations of such non-hydrocarbon oxygen-atom-containing linking groups with alkylene groups. A sulfonyl group (-SO2-) may be further linked to this combination. Examples of such divalent linking groups containing an oxygen atom include linking groups represented by the following general formulae (y-al-1) to (y-al-7). In the following general formulae (y-al-1) to (y-al-7), R in the above formula (b-1-an) 101 The bond to V' in the following general formulas (y-al-1) to (y-al-7) is 101 is.

[0233] [ka] [In the formula, V' 101 is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' 102 is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.

[0234] V' 102 The divalent saturated hydrocarbon group in is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

[0235] V' 101 and V' 102 The alkylene group in may be a straight-chain alkylene group or a branched-chain alkylene group, and is preferably a straight-chain alkylene group. V' 101 and V' 102Specific examples of the alkylene group in the formula (I) include a methylene group [-CH2-]; alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; an ethylene group [-CH2CH2-]; -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, and -CH(CH2CH3)CH2 -, etc.; a trimethylene group (n-propylene group) [-CH2CH2CH2-]; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; a tetramethylene group [-CH2CH2CH2CH2-]; alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-; and a pentamethylene group [-CH2CH2CH2CH2CH2-]. Also, V' 101 or V' 102 In the formula (a1-r-1), some of the methylene groups in the alkylene group may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is represented by Ra' in the formula (a1-r-1). 3 A divalent group obtained by removing one more hydrogen atom from a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group) of the above is preferred, and a cyclohexylene group, a 1,5-adamantylene group or a 2,6-adamantylene group is more preferred.

[0236] Y 101 As the linking group, 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 (y-al-1) to (y-al-5) are more preferred.

[0237] In formula (b-1-an), V 101 is a single bond, an alkylene group, or a fluorinated alkylene group. 101 The alkylene group and fluorinated alkylene group in the formula (V) preferably have 1 to 4 carbon atoms. 101 The fluorinated alkylene group in 101In particular, groups in which some or all of the hydrogen atoms of the alkylene group in the formula (I) are substituted with fluorine atoms are preferred. 101 is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

[0238] In formula (b-1-an), R 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 102 is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

[0239] Specific examples of the anion moiety represented by the formula (b-1-an) include, for example, Y 101 When Y is a single bond, examples of the anion include a fluorinated alkylsulfonate anion such as a trifluoromethanesulfonate anion or a perfluorobutanesulfonate anion; 101 When is a divalent linking group containing an oxygen atom, examples of the anions include those represented by any of the following formulae (an-1) to (an-3).

[0240] [ka] [In the formula, R” 101 R" is an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by each of the above chemical formulas (r-hr-1) to (r-hr-6), a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), or a chain alkyl group which may have a substituent. 102 R" is an aliphatic cyclic group which may have a substituent, a fused cyclic group represented by the formula (r-br-1) or (r-br-2) above, a lactone-containing cyclic group represented by each of the general formulae (a2-r-1), (a2-r-3) to (a2-r-7) above, or an -SO2- containing cyclic group represented by each of the general formulae (a5-r-1) to (a5-r-4) above. 103 V" 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. 101is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms; each v" is independently an integer of 0 to 3, each q" is independently an integer of 0 to 20, and n" is 0 or 1.

[0241] R” 101 , R” 102 and R” 103 The aliphatic cyclic group which may have a substituent is represented by R 101 The substituent is preferably a group exemplified as the cyclic aliphatic hydrocarbon group in the formula (b-1-an). 101 Examples of the substituents that may be substituted on the cyclic aliphatic hydrocarbon group in the above formula (1) include the same as those that may be substituted on the cyclic aliphatic hydrocarbon group in the above formula (1).

[0242] R” 103 The aromatic cyclic group which may have a substituent in the formula (b-1-an) is R 101 The substituent is preferably a group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in the formula (b-1-an). 101 Examples of the substituents that may substitute the aromatic hydrocarbon group in the above formula (1) include the same as those in the above formula (1).

[0243] R” 101 The chain alkyl group which may have a substituent in the formula (b-1-an) is R 101 The alkyl group is preferably one of the groups exemplified as the chain alkyl group in the above formula. R” 103 The chain alkenyl group which may have a substituent in the formula (b-1-an) is R 101 Preferably, it is a group exemplified as the chain alkenyl group in the above formula.

[0244] Specific examples of the anion moiety represented by formula (b-1-an) are shown below, but are not limited to these.

[0245] [ka]

[0246] Anion represented by the formula (b-2-an) In formula (b-2-an), 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 represented by R 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 chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and even more preferably 1 to 3 carbon atoms. 104 , R 105 The number of carbon atoms in the chain alkyl group of R is preferably as small as possible within the above range of carbon atoms, for reasons such as good solubility in resist solvents. 104 , R 105 In the chain alkyl group, the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength and the improved transparency to high-energy light of 250 nm or less and electron beams, which is preferable. The proportion of fluorine atoms in the chain alkyl group, i.e., 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 formula (b-2-an), V 102 , V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each represents V in formula (b-1-an). 101 The same can be mentioned. In formula (b-2-an), L 101 , L 102 are each independently a single bond or an oxygen atom.

[0247] Anion represented by the formula (b-3-an) In formula (b-3-an), R 106 ~R 108 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 represented by R 101 The same can be mentioned. In formula (b-3-an), L 103 ~L 105 are each independently a single bond, —CO— or —SO2—.

[0248] Among the above, Xb - As the anion, anions represented by formula (b-1-an) are preferred. Among these, anions represented by any of the above general formulas (an-1) to (an-3) are more preferred, anions represented by any of general formulas (an-1) or (an-2) are even more preferred, and anions represented by general formula (an-1) are particularly preferred.

[0249] Specific examples of the component (B0) are shown below, but are not limited to these.

[0250] [ka]

[0251] [ka]

[0252] [ka]

[0253] [ka]

[0254] In the resist composition of this embodiment, as the component (B0), one type of compound may be used alone, or two or more types may be used in combination. In the resist composition of this embodiment, the amount of the component (B0) relative to 100 parts by mass of the component (A) is preferably 5 to 40 parts by mass, more preferably 10 to 40 parts by mass, even more preferably 12 to 40 parts by mass, and particularly preferably 15 to 35 parts by mass. When the amount of component (B0) is at least as large as the lower limit of the above-mentioned preferred range, lithography properties such as sensitivity, reduced LWR (line width roughness), pattern shape, and reduced defects are further improved during resist pattern formation. On the other hand, when the amount is at most the upper limit of the preferred range, a homogeneous solution is more easily obtained when the components of the resist composition are dissolved in an organic solvent, and the storage stability of the resist composition is further improved.

[0255] In the resist composition of this embodiment, the proportion of the component (B0) within the entire component (B) is, for example, 50 mass % or more, preferably 70 mass % or more, and even more preferably 95 mass % or more, and may even be 100 mass %.

[0256] The component (B) in the resist composition of this embodiment may also contain an acid generator component (B1) (hereafter, also referred to as "component (B1)") other than the above-mentioned component (B0).

[0257] ≪(B1) Component≫ Examples of the component (B1) include onium salt-based acid generators such as iodonium salts and sulfonium salts (excluding those corresponding to the component (B0)); oxime sulfonate-based acid generators; diazomethane-based acid generators such as bisalkyl- or bisarylsulfonyldiazomethanes and poly(bissulfonyl)diazomethanes; nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

[0258] Examples of the onium salt acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1)"), a compound represented by general formula (b-2) (hereinafter also referred to as "component (b-2)"), or a compound represented by general formula (b-3) (hereinafter also referred to as "component (b-3)").

[0259] [ka] [In the formula, R 101 and R 104 ~R 108 R each independently represents 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. 104 and R 105 R may be bonded to each other to form a ring structure. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 101 is a divalent linking group containing an oxygen atom or a single bond. 101 ~V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group. 101 ~L 102 are each independently a single bond or an oxygen atom. 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.

[0260] {anion part} Anion in component (b-1) The anion moiety in the component (b-1) is an anion represented by the above formula (b-1-an).

[0261] Anion in component (b-2) The anion moiety in the component (b-2) is an anion represented by the above formula (b-2-an).

[0262] Anion in component (b-3) The anion moiety in the component (b-3) is an anion represented by the above formula (b-3-an).

[0263] Among the above, the anion moiety of component (B1) is preferably an anion represented by formula (b-1-an).Of these, an anion represented by any of the above general formulae (an-1) to (an-3) is more preferred, an anion represented by either general formula (an-1) or (an-2) is even more preferred, and an anion represented by general formula (an-2) is particularly preferred.

[0264] {cation part} In the formula (b-1), formula (b-2), and formula (b-3), M m+ represents an m-valent onium cation. Among these, sulfonium cation and iodonium cation are preferred. m is an integer of 1 or greater.

[0265] Preferred cationic moieties ((M m+ ) 1 / m ) includes organic cations represented by the following general formulas (ca-1) to (ca-5) (excluding those corresponding to the cation (C0)).

[0266] [ka] [In the formula, R 201 ~R 207 , and R 211 ~R 212 R each independently represents an aryl group, an alkyl group, or an alkenyl group which may have a substituent. 201 ~R 203 , R 206 ~R 207 , R 211 ~R 212 may be bonded to each other to form a ring together with the sulfur atom in the formula. 208 ~R 209 R each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 210is an optionally substituted aryl group, an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted SO2-containing cyclic group. 201 represents -C(=O)- or -C(=O)-O-. Y 201 each independently represents an arylene group, an alkylene group, or an alkenylene group. x is 1 or 2. W 201 represents a (x+1)-valent linking group.

[0267] In the above general formulas (ca-1) to (ca-5), R 201 ~R 207 , and R 211 ~R 212 The aryl group in the formula (I) includes an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group or a naphthyl group is preferred. R 201 ~R 207 , and R 211 ~R 212 The alkyl group in the formula (I) is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms. R 201 ~R 207 , and R 211 ~R 212 The alkenyl group in the formula (I) preferably has 2 to 10 carbon atoms. R 201 ~R 207 , and R 210 ~R 212 Examples of the substituent that may be possessed by the group include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and groups represented by the following general formulae (ca-r-1) to (ca-r-7).

[0268] [ka] [In the formula, R' 201 are each independently a hydrogen atom, 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.

[0269] Optionally substituted cyclic groups: 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. An aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

[0270] R' 201 The aromatic hydrocarbon group in the formula (I) is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, even more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. However, this number of carbon atoms does not include the number of carbon atoms in the substituent. R' 201 Specific examples of the aromatic ring contained in the aromatic hydrocarbon group in the above formula include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. R' 201 Specific examples of the aromatic hydrocarbon group in include a group in which one hydrogen atom has been removed 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 has been substituted with an alkylene group (for example, arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The alkylene group (the alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

[0271] R' 201 The cyclic aliphatic hydrocarbon group in the formula (I) is an aliphatic hydrocarbon group containing a ring in the structure. Examples of aliphatic hydrocarbon groups that contain a ring in their structure include alicyclic hydrocarbon groups (groups in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is interposed in the middle of a straight-chain or branched-chain 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. The monocyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among these, the polycycloalkane is more preferably a polycycloalkane having a bridged ring polycyclic skeleton, such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; or a polycycloalkane having a fused ring polycyclic skeleton, such as a cyclic group having a steroid skeleton.

[0272] Among them, R' 201 The cyclic aliphatic hydrocarbon group in is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, particularly preferably an adamantyl group or a norbornyl group, and most preferably an adamantyl group.

[0273] The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferred, and specific examples include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-]. The branched aliphatic hydrocarbon group is preferably a branched alkylene group, and specific examples thereof include alkyl alkylene groups such as alkylmethylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0274] Also, R' 201 The cyclic hydrocarbon group in may contain a heteroatom, such as a heterocycle. Specific examples include the lactone-containing cyclic groups represented by the general formulae (a2-r-1) to (a2-r-7) above, the —SO—-containing cyclic groups represented by the general formulae (a5-r-1) to (a5-r-4) above, and other heterocyclic groups represented by the chemical formulae (r-hr-1) to (r-hr-16) above.

[0275] R' 201 Examples of the substituent in the cyclic group include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group. The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. The alkoxy group as a 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 most preferably a methoxy group or an ethoxy group. As the halogen atom as a substituent, a fluorine atom is preferred. Examples of halogenated alkyl groups as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms. The carbonyl group as a substituent is a group that substitutes a methylene group (-CH2-) that constitutes a cyclic hydrocarbon group.

[0276] A chain alkyl group which may have a substituent: R' 201 The chain alkyl group may be either a straight chain or a branched chain. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0277] An optionally substituted chain alkenyl group: R' 201The chain alkenyl group may be either linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, even more preferably 2 to 4 carbon atoms, and particularly preferably 3 carbon atoms. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group. Of the chain alkenyl groups mentioned above, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

[0278] R' 201 Examples of the substituent in the chain alkyl or alkenyl group include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, the above-mentioned R' 201 Examples of the cyclic groups include the cyclic groups shown in the formula:

[0279] R' 201 In addition to those mentioned above, the optionally substituted cyclic group, the optionally substituted chain alkyl group, or the optionally substituted chain alkenyl group also includes the same as the acid-dissociable group represented by formula (a1-r-2) above as the optionally substituted cyclic group or the optionally substituted chain alkyl group.

[0280] Among them, R' 201 is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, for example, a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane, a lactone-containing cyclic group represented by each of the general formulae (a2-r-1) to (a2-r-7), or an —SO2- containing cyclic group represented by each of the general formulae (a5-r-1) to (a5-r-4) is preferred.

[0281] In the above general formulas (ca-1) to (ca-5), R 201 ~R203 , R 206 ~R 207 , R 211 ~R 212 When they are bonded to each other to form a ring together with the sulfur atom in the formula, they may not contain a heteroatom such as a sulfur atom, an oxygen atom, or a nitrogen atom, or 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, inclusive of the sulfur atom. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene 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.

[0282] 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.

[0283] 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) includes 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 the formula (I) 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. R 210As the optionally substituted SO2-containing cyclic group in the above, an "-SO2-containing polycyclic group" is preferred, and a group represented by the above general formula (a5-r-1) is more preferred.

[0284] Y 201 each independently represents an arylene group, an alkylene group, or an alkenylene group. Y 201 The arylene group in the formula (b-1-an) is R 101 Examples of the aromatic hydrocarbon group in the above formula include groups in which one hydrogen atom has been removed from the aryl groups exemplified above. Y 201 The alkylene group and alkenylene group in the above formula (b-1-an) are the same as R 101 Examples of the chain alkyl group and the chain alkenyl group include groups in which one hydrogen atom has been removed from the groups exemplified above as the chain alkyl group and the chain alkenyl group.

[0285] In the formula (ca-4), x is 1 or 2. W 201 is an (x+1)-valent, i.e., a divalent or trivalent linking group. W 201 The divalent linking group in the formula (a2-1) is preferably a divalent hydrocarbon group which may have a substituent. 21 Examples of the divalent hydrocarbon groups include those shown below, which may have a substituent. 201 The divalent linking group in may be linear, branched, or cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group is preferred. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferred. W 201 The trivalent linking group in 201 Examples of the divalent linking group include a group in which one hydrogen atom has been removed from the divalent linking group shown in the formula (1), and a group in which the divalent linking group is further bonded to the divalent linking group shown in the formula (1). 201 The trivalent linking group in the formula (I) is preferably a group in which two carbonyl groups are bonded to an arylene group.

[0286] Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following chemical formulas (ca-1-1) to (ca-1-70).

[0287] [ka]

[0288] [ka]

[0289] [ka] [In the formula, g1, g2, and g3 represent the number of repeating units, where g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20.]

[0290] [ka]

[0291] [ka]

[0292] [ka] [In the formula, R” 201 is a hydrogen atom or a substituent, and the substituent is the same as R 201 ~R 207 , and R 210 ~R 212 The substituents are the same as those exemplified as the substituents that may be possessed by the group

[0293] Specific examples of suitable cations represented by the formula (ca-2) include diphenyliodonium cation, bis(4-tert-butylphenyl)iodonium cation, and the like.

[0294] Specific examples of suitable cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

[0295] [ka]

[0296] Specific examples of suitable cations represented by the formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

[0297] [ka]

[0298] Specific examples of suitable cations represented by the formula (ca-5) include cations represented by the following general formulas (ca-5-1) to (ca-5-3).

[0299] [ka]

[0300] Among the above, the cation part ((M m+ ) 1 / m ) is preferably a cation represented by general formula (ca-1).

[0301] In the resist composition of this embodiment, the component (B1) may be used either as a single type, or in combination of two or more types. When the resist composition contains the component (B1), the amount of the component (B1) in the resist composition is preferably less than 40 parts by mass, more preferably 1 to 30 parts by mass, and even more preferably 1 to 20 parts by mass, per 100 parts by mass of the component (A). By ensuring that the amount of the component (B1) falls within this preferred range, defects are likely to be reduced. Furthermore, when the components of the resist composition are dissolved in an organic solvent, a homogeneous solution is likely to be obtained, and the storage stability of the resist composition is improved. The resist composition of this embodiment preferably does not contain the component (B1).

[0302] <Other ingredients> The resist composition of this embodiment may further contain other components in addition to the above-described components (A) and (B). Examples of other components include the following components (D), (E), (F), and (S).

[0303] <Acid diffusion controller component (D)> In addition to the component (A), the resist composition of this embodiment may further contain an acid diffusion controller component (component (D)) that traps the acid generated upon exposure (i.e., controls the diffusion of the acid). The component (D) acts as a quencher (acid diffusion controller) that traps the acid generated in the resist composition upon exposure. Examples of the component (D) include a photodegradable base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its acid diffusion controllability, and a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not fall under the category of component (D1). Among these, the photodegradable base (component (D1)) is preferred because it is likely to enhance all of the properties of high sensitivity, reduced roughness, and suppressed occurrence of coating defects.

[0304] Regarding component (D1) By using a resist composition that contains the component (D1), the contrast between exposed and unexposed areas of the resist film can be further improved when forming a resist pattern. The component (D1) is not particularly limited as long as it decomposes upon exposure to light and loses its acid diffusion controllability, and is preferably one or more compounds selected from the group consisting of a compound represented by the following general formula (d1-1) (hereinafter referred to as "component (d1-1)"), a compound represented by the following general formula (d1-2) (hereinafter referred to as "component (d1-2)"), and a compound represented by the following general formula (d1-3) (hereinafter referred to as "component (d1-3)"): The components (d1-1) to (d1-3) do not act as quenchers in the exposed areas of the resist film because they decompose and lose their acid diffusion control properties (basicity), but act as quenchers in the unexposed areas of the resist film.

[0305] [ka] [In the formula, Rd 1 ~Rd 4 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. 2 In this case, no fluorine atom is bonded to the carbon atom adjacent to the S atom. 1 is a single bond or a divalent linking group; m is an integer of 1 or more; M m+ are each independently an m-valent organic cation.

[0306] {(d1-1) component} Anion part In formula (d1-1), Rd 1 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 each of the R' 201 The same can be mentioned. Among these, Rd 1is preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like 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 the above general formulas (a2-r-1) to (a2-r-7), an ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is contained as a substituent, it may be via an alkylene group, and in this case, the substituent is preferably a linking group represented by the above formulas (y-al-1) to (y-al-5). Note that Rd 1 When the aromatic hydrocarbon group, the aliphatic cyclic group, or the chain alkyl group in the formula (d3-1) has a linking group represented by the general formulas (y-al-1) to (y-al-7) as a substituent, in the general formulas (y-al-1) to (y-al-7), Rd 1 The carbon atom constituting the aromatic hydrocarbon group, the aliphatic cyclic group, or the chain alkyl group in the formula (y-al-1) to (y-al-7) is bonded to V' 101 is. Suitable examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and another ring structure). The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. The chain alkyl group preferably has 1 to 10 carbon atoms, and specific examples thereof include straight-chain alkyl groups such as 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 nonyl group, and a decyl group; and branched-chain alkyl groups such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

[0307] When the chain-like alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms in the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and even more preferably 1 to 4. The fluorinated alkyl group may contain atoms other than fluorine atoms. Examples of atoms other than fluorine atoms include oxygen atoms, sulfur atoms, and nitrogen atoms.

[0308] Preferred examples of the anion moiety of the component (d1-1) are shown below.

[0309] [ka]

[0310] Cation part In formula (d1-1), M m+ is an m-valent organic cation. M m+ Suitable organic cations include those similar to those represented by the general formulae (ca-1) to (ca-5), with the cation represented by the general formula (ca-1) being more preferred, and the cations represented by the general formulae (ca-1-1) to (ca-1-78) being even more preferred.

[0311] The component (d1-1) may be used alone or in combination of two or more.

[0312] {(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 R' 201 The same can be mentioned. However, Rd 2In this case, the carbon atom adjacent to the S atom is not bonded to a fluorine atom (is not fluorinated), which makes the anion of component (d1-2) an appropriately weak acid anion, thereby improving the quenching ability of component (D). Road 2 is preferably a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent. The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 3 to 10. The aliphatic cyclic group is more preferably a group (which may have a substituent) in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc.; or a group in which one or more hydrogen atoms have been removed from camphor, etc. Road 2 The hydrocarbon group may have a substituent, and the substituent may be Rd 1 Examples of the substituents include the same as those that may be contained in the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in the above.

[0313] Preferred examples of the anion moiety of the component (d1-2) are shown below.

[0314] [ka]

[0315] Cation part In formula (d1-2), M m+ is an m-valent organic cation, and M in the formula (d1-1) m+ is the same as: The component (d1-2) may be used alone or in combination of two or more.

[0316] {(d1-3) component} Anion part In formula (d1-3), Rd 3is 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 201 The Rd is preferably a fluorine atom-containing cyclic group, a chain alkyl group, or a chain alkenyl group. Among these, a fluorinated alkyl group is preferred, and the Rd 1 The same fluorinated alkyl groups as those mentioned above are more preferred.

[0317] In formula (d1-3), Rd 4 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 R' 201 The same can be mentioned. Among these, alkyl groups, alkoxy groups, alkenyl groups and cyclic groups which may have a substituent are preferred. Road 4 The alkyl group in Rd is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof 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, and a neopentyl group. 4 A portion of the hydrogen atoms of the alkyl group may be substituted with a hydroxyl group, a cyano group, or the like. Road 4 The alkoxy group in is preferably an alkoxy group having 1 to 5 carbon atoms, and 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. Of these, a methoxy group and an ethoxy group are preferred.

[0318] Road 4 The alkenyl group in R' 201 Examples include the same alkenyl groups as those in the above, and vinyl, propenyl (allyl), 1-methylpropenyl, and 2-methylpropenyl groups are preferred. These groups may further have an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms as a substituent.

[0319] Road 4 The cyclic group in the formula (I) is the same as the R' 201 Examples of the cyclic group include the same as the cyclic group in the above, and preferred are alicyclic groups obtained by removing one or more hydrogen atoms from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane, or aromatic groups such as a phenyl group or a naphthyl group. 4 When Rd is an alicyclic group, the resist composition dissolves well in an organic solvent, resulting in excellent lithography properties. 4 When is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition exhibits excellent light absorption efficiency, and exhibits favorable sensitivity and lithography properties.

[0320] 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, but examples thereof include a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, and a divalent linking group containing a hetero atom. 21 Examples of the divalent linking group include the same divalent hydrocarbon groups which may have a substituent and divalent linking groups containing a hetero atom as those mentioned in the description of the divalent linking group in the above. Yd 1 is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, and further preferably a methylene group or an ethylene group.

[0321] Preferred examples of the anion moiety of the component (d1-3) are shown below.

[0322] [ka]

[0323] [ka]

[0324] Cation part In formula (d1-3), M m+ is an m-valent organic cation, and M in the formula (d1-1) m+ is the same as: The component (d1-3) may be used alone or in combination of two or more.

[0325] The component (D1) may be any one of the components (d1-1) to (d1-3) above, or a combination of two or more of them. When the resist composition contains the component (D1), the amount of the component (D1) in the resist composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 8 parts by mass, per 100 parts by mass of the component (A1). When the amount of the component (D1) is at least as large as the preferred lower limit, particularly good lithography properties and resist pattern shape are likely to be obtained, while when it is at most the upper limit, good sensitivity can be maintained and excellent throughput can be achieved.

[0326] Manufacturing method of component (D1): The method for producing the components (d1-1) and (d1-2) is not particularly limited, and they can be produced by known methods. The method for producing component (d1-3) is not particularly limited, and it can be produced, for example, in a manner similar to that described in US2012-0149916.

[0327] Regarding component (D2) The component (D) may contain a nitrogen-containing organic compound component (hereinafter referred to as "component (D2)") that does not fall under the category of the component (D1) described above. The component (D2) is not particularly limited as long as it acts as an acid diffusion controller and does not fall under the category of component (D1), and any known component may be used. Among these, aliphatic amines are preferred, and among these, secondary aliphatic amines and tertiary aliphatic amines are particularly preferred. An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms. Examples of aliphatic amines include amines in which at least one hydrogen atom of ammonia NH3 has been substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms (alkylamines or alkyl alcohol amines), and cyclic amines. Specific examples of alkylamines and alkyl alcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkyl alcoholamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

[0328] Examples of cyclic amines include heterocyclic compounds containing a nitrogen atom as a heteroatom. The heterocyclic compounds may be monocyclic (aliphatic monocyclic amines) or polycyclic (aliphatic polycyclic amines). Specific examples of the aliphatic monocyclic amine include piperidine and piperazine. The aliphatic polycyclic amine is preferably one having 6 to 10 carbon atoms, and specific examples thereof 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.

[0329] 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, and triethanolamine triacetate, with triethanolamine triacetate being preferred.

[0330] Furthermore, an aromatic amine may be used as the component (D2). Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, and N-tert-butoxycarbonylpyrrolidine.

[0331] The component (D2) may be used alone or in combination of two or more. When the resist composition contains the component (D2), the amount of the component (D2) within the resist composition is typically within a range from 0.01 to 5 parts by mass per 100 parts by mass of the component (A1). By ensuring this range, the resist pattern shape and stability over time during storage can be improved.

[0332] <<At least one compound (E) selected from the group consisting of organic carboxylic acids, phosphorus oxoacids, and derivatives thereof>> The resist composition of this embodiment may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids, and phosphorus oxo acids and derivatives thereof (hereafter referred to as "component (E)") for the purposes of preventing sensitivity degradation and improving the resist pattern shape and stability over time after exposure. Specific examples of organic carboxylic acids include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid, with salicylic acid being preferred. Examples of phosphorus oxoacids include phosphoric acid, phosphonic acid, and phosphinic acid, with phosphonic acid being particularly preferred. Examples of derivatives of phosphorus oxoacids include esters in which the hydrogen atoms of the above oxoacids are substituted with hydrocarbon groups, and examples of the hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms and aryl groups having 6 to 15 carbon atoms. Examples of the derivatives of phosphoric acid include phosphoric acid esters such as di-n-butyl phosphoric acid ester and diphenyl phosphoric acid ester. Examples of the derivatives of phosphonic acid include phosphonic acid esters such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, and dibenzyl phosphonate. Derivatives of phosphinic acid include phosphinic acid esters and phenylphosphinic acid. In the resist composition of this embodiment, the component (E) may be used either as a single type, or in combination of two or more types. When the resist composition contains the component (E), the amount of the component (E) per 100 parts by mass of the component (A) is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass. By ensuring that the amount is within this range, the sensitivity, lithography properties, and the like are improved.

[0333] <Fluorine additive component (F)> The resist composition of this embodiment may contain a fluorine additive component (hereafter referred to as “component (F)”) in order to impart water repellency to the resist film or to improve lithography properties. As the component (F), for example, the fluorine-containing polymer compounds described in JP-A Nos. 2010-002870, 2010-032994, 2010-277043, 2011-13569, and 2011-128226 can be used. More specifically, component (F) may be a polymer having a structural unit (f1) represented by the following general formula (f1-1): This polymer is preferably a polymer (homopolymer) consisting solely of the structural unit (f1) represented by the following formula (f1-1); a copolymer of the structural unit (f1) with the structural unit (a1); or a copolymer of the structural unit (f1) with a structural unit derived from acrylic acid or methacrylic acid and the structural unit (a1), more preferably a copolymer of the structural unit (f1) with the structural unit (a1). Here, the structural unit (a1) copolymerized with the structural unit (f1) is preferably a structural unit derived from 1-ethyl-1-cyclooctyl(meth)acrylate or a structural unit derived from 1-methyl-1-adamantyl(meth)acrylate, more preferably a structural unit derived from 1-ethyl-1-cyclooctyl(meth)acrylate.

[0334] [ka] [wherein R is the same as defined above, and Rf 102 and Rf 103 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; Rf 102 and Rf 103 may be the same or different. 1 is an integer from 0 to 5, and Rf 101 is an organic group containing a fluorine atom.

[0335] In formula (f1-1), R bonded to the carbon atom at the α-position is the same as defined above. R is preferably a hydrogen atom or a methyl group. In formula (f1-1), Rf 102 and Rf 103The halogen atom in Rf is preferably a fluorine atom. 102 and Rf 103 Examples of the alkyl group having 1 to 5 carbon atoms in Rf include the same alkyl groups having 1 to 5 carbon atoms as those in R, and a methyl group or an ethyl group is preferred. 102 and Rf 103 Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is preferred. Among these, Rf 102 and Rf 103 is preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom. In formula (f1-1), nf 1 is an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.

[0336] In formula (f1-1), Rf 101 is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom. The fluorine atom-containing hydrocarbon group may be linear, branched, or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and particularly preferably 1 to 10 carbon atoms. Furthermore, in the fluorine atom-containing hydrocarbon group, preferably 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more, and particularly preferably 60% or more, because this increases the hydrophobicity of the resist film during immersion exposure. Among them, Rf 101 is more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, and particularly preferably a trifluoromethyl group, -CH2-CF3, -CH2-CF2-CF3, -CH(CF3)2, -CH2-CH2-CF3, or -CH2-CH2-CF2-CF2-CF2-CF3.

[0337] The weight-average molecular weight (Mw) of component (F) (based on polystyrene standards measured by gel permeation chromatography) is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and most preferably 10,000 to 30,000. When the Mw is below the upper limit of this range, the component has sufficient solubility in a resist solvent for use as a resist, and when the Mw is above the lower limit of this range, the resulting resist film has good water repellency. 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.

[0338] In the resist composition of this embodiment, the component (F) may be used either as a single type, or in combination of two or more types. When the resist composition contains the component (F), the amount of the component (F) is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of the component (A).

[0339] <Organic solvent component (S)> The resist composition of this embodiment can be produced by dissolving the resist materials in an organic solvent component (hereafter referred to as “component (S)”). The component (S) can be any solvent that is capable of dissolving the individual components used and forming a homogeneous solution, and any solvent that is appropriately selected from among those known as solvents for conventional chemically amplified resist compositions can be used. Examples of the component (S) include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; and compounds having an ether bond such as monoalkyl ethers or monophenyl ethers of the above polyhydric alcohols or compounds having an ester bond, such as monomethyl ether, monoethyl ether, monopropyl ether, and monobutyl ether. Examples of suitable solvents include derivatives of polyhydric alcohols (among which, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred); cyclic ethers such as dioxane, and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, and mesitylene, and dimethyl sulfoxide (DMSO). In the resist composition of this embodiment, the component (S) may be used either alone or as a mixed solvent of two or more different solvents. Of these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0340] A mixed solvent of PGMEA and a polar solvent is also preferred as component (S). The blending ratio (mass ratio) may be determined appropriately taking into consideration the compatibility of PGMEA with the polar solvent, but is preferably within the range of 1:9 to 9:1, and more preferably 2:8 to 8:2. More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA:EL or cyclohexanone is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. When PGME is blended as the polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, and even more preferably 3:7 to 7:3. Furthermore, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferred. Another preferred component (S) is a mixed solvent of at least one selected from PGMEA and EL with γ-butyrolactone, in which the mass ratio of the former to the latter is preferably 70:30 to 95:5. There are no particular restrictions on the amount of component (S) used, and it is set appropriately depending on the coating film thickness so as to provide a concentration that allows application to a substrate, etc. Generally, the component (S) is used so that the solids concentration of the resist composition falls within the range of 0.1 to 20 mass %, and preferably 0.2 to 15 mass %.

[0341] The resist composition of this embodiment may further contain, if desired, compatible additives such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, or a dye.

[0342] The resist composition of this embodiment may be prepared by dissolving the resist material in component (S) and then removing impurities using a polyimide porous film, a polyamideimide porous film, or the like. For example, the resist composition may be filtered using a filter made of a polyimide porous film, a filter made of a polyamideimide porous film, or a filter made of a polyimide porous film and a polyamideimide porous film. Examples of such polyimide porous films and polyamideimide porous films include those described in JP 2016-155121 A.

[0343] The resist composition of this embodiment described above contains, as the component (B), a compound (B0) that includes a cation (C0). The cation (C0) is a low LUMO cation with a planar structure. By including the cation (C0), the compound (B0) improves the efficiency of acid generation upon exposure. As a result, the sensitivity of a resist composition containing the compound (B0) is improved. Furthermore, the cation (C0) has two or more electron-withdrawing groups in the phenyl group, which improves its solubility in the component (S). Furthermore, during development after exposure, its solubility in a developer is improved. This allows a resist composition containing the compound (B0) to reduce defects. As described above, the resist composition of this embodiment can achieve both high sensitivity and reduced defects.

[0344] [Second embodiment] The resist composition of the second embodiment contains a compound (C) as the component (D). The resist composition of the second embodiment contains a component (A) whose solubility in a developer changes under the action of an acid, and an acid diffusion controller component (D) that controls the diffusion of acid generated by exposure. The acid diffusion controller component (D) includes a compound represented by the following general formula (d0):

[0345] [ka] [In the formula, M d+ is the cation (C0). Xd - is the counter anion.

[0346] <Component (A)> The component (A) may be the same as the component (A) in the first embodiment. The component (A) preferably contains a resin component (A1) whose solubility in a developer changes under the action of an acid. The component (A1) may be the same as the component (A1) in the first embodiment. One type of component (A1) may be used alone, or two or more types may be used in combination.

[0347] The amount of the component (A) in the resist composition of this embodiment may be adjusted depending on factors such as the thickness of the resist film to be formed.

[0348] <(D) component> The resist composition of this embodiment contains an acid diffusion controller component (D) that traps acid generated by exposure (i.e., controls the diffusion of acid). The component (D) includes a compound (D0) (hereinafter also referred to as "component (D0)") represented by the following general formula (d0). Compound (D0) is a photodegradable base that decomposes upon exposure and loses its acid diffusion controllability.

[0349] ≪(D0) component≫ The component (D0) is a compound represented by the following general formula (d0).

[0350] [ka] [In the formula, M d+ is the cation (C0). Xd - is the counter anion.

[0351] {cation part} In the general formula (d0), M d+ is the cation (C0).

[0352] {anion part} In the general formula (d0), Xd - is the counter anion. Xd - is not particularly limited, and any of those proposed as the anion moiety of a photodegradable base for a chemically amplified resist composition can be used.

[0353] Xd - Examples of the anions include those represented by the following general formula (d-1-an), general formula (d-2-an), and general formula (d-3-an).

[0354] [ka] [In the formula, Rd1 ~Rd 4 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. 2 In this case, no fluorine atom is bonded to the carbon atom adjacent to the S atom. 1 is a single bond or a divalent linking group; m is an integer of 1 or more; M m+ are each independently an m-valent organic cation.

[0355] Anion represented by the formula (d-1-an) The anion represented by formula (d-1-an) is the same as the anion moiety of the component (d1-1).

[0356] Anion represented by the formula (d-2-an) The anion represented by formula (d-2-an) is the same as the anion moiety of the component (d1-2).

[0357] Anion represented by the formula (d-3-an) The anion represented by formula (d-3-an) is the same as the anion moiety of the component (d1-3).

[0358] Among the above, Xd - is preferably an anion represented by formula (d-1-an).

[0359] Specific examples of the component (D0) are shown below, but are not limited to these.

[0360] [ka]

[0361] [ka]

[0362] [ka]

[0363] [ka]

[0364] In the resist composition of this embodiment, as the component (D0), one type of compound may be used alone, or two or more types may be used in combination. In the resist composition of this embodiment, the amount of the component (D0) relative to 100 parts by mass of the component (A) is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 8 parts by mass. When the amount of the component (D0) is at least as large as the lower limit of the above preferred range, good lithography properties and good resist pattern shape are likely to be obtained, while when it is at most the upper limit, good sensitivity can be maintained and excellent throughput can be achieved.

[0365] In the resist composition of this embodiment, the proportion of the component (D0) within the entire component (D) is, for example, 50 mass% or more, preferably 70 mass% or more, and even more preferably 95 mass% or more, and may even be 100 mass%.

[0366] The component (D) in the resist composition of this embodiment may contain an acid diffusion controller component other than the above-mentioned component (D0). Examples of acid diffusion controller components other than component (D0) include a photodegradable base (D1) (hereinafter referred to as "component (D1)") that decomposes upon exposure and loses its acid diffusion control properties (excluding those that fall under the category of component (D0)), and a nitrogen-containing organic compound (D2) (hereinafter referred to as "component (D2)") that does not fall under the category of component (D1).

[0367] <Component (D1)> The component (D1) can be the same as the component (D1) in the first embodiment.

[0368] The component (D1) may be used alone or in combination of two or more. When the resist composition of this embodiment contains the component (D1), the amount of the component (D1) in the resist composition is preferably less than 20 parts by mass, more preferably less than 15 parts by mass, and even more preferably less than 8 parts by mass, per 100 parts by mass of the component (A1). By adjusting the content of the component (D1) within the above-mentioned preferred range, defects are likely to be reduced. The resist composition of this embodiment preferably does not contain the component (D1).

[0369] ≪(D2) component≫ The component (D2) can be the same as the component (D2) in the first embodiment.

[0370] The component (D2) may be used alone or in combination of two or more. When the resist composition of this embodiment contains the component (D2), the amount of the component (D2) in the resist composition is preferably less than 10 parts by mass, and more preferably less than 5 parts by mass, per 100 parts by mass of the component (A1). By adjusting the content of the component (D2) within the above-mentioned preferred range, defects are likely to be reduced. The resist composition of this embodiment preferably does not contain the component (D2).

[0371] <Other ingredients> The resist composition of this embodiment may further contain other components in addition to the above-described components (A) and (D). Examples of other components include the following components (B), (E), (F), and (S).

[0372] ≪(B) Component≫ The resist composition of this embodiment preferably contains the component (B). The component (B) can be the same as the component (B1) in the first embodiment.

[0373] In the resist composition of this embodiment, the component (B) may be used either as a single type, or in combination of two or more types. In the resist composition of this embodiment, the amount of the component (B) relative to 100 parts by mass of the component (A) is preferably 5 to 40 parts by mass, more preferably 10 to 40 parts by mass, even more preferably 12 to 40 parts by mass, and particularly preferably 15 to 35 parts by mass. By ensuring that the amount of component (B) falls within the above-mentioned preferred range, sufficient pattern formation is achieved. Furthermore, when the components of the resist composition are dissolved in an organic solvent, a homogeneous solution is easily obtained, and the storage stability of the resist composition is also favorable.

[0374] ≪(E) Component≫ The resist composition of this embodiment may contain a component (E). The component (E) can be the same as the component (E) in the first embodiment. In the resist composition of this embodiment, the component (E) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (E), the amount of the component (E) relative to 100 parts by mass of the component (A) is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass. By ensuring that the amount is within this range, the sensitivity, lithography properties, and the like are improved.

[0375] <(F) Component> The resist composition of this embodiment may contain a component (F). The component (F) can be the same as the component (E) in the first embodiment. In the resist composition of this embodiment, the component (F) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (F), the amount of the component (F) relative to 100 parts by mass of the component (A) is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass.

[0376] ≪(S) component≫ The component (S) can be the same as the component (S) in the first embodiment. There are no particular restrictions on the amount of component (S) used, and it is set appropriately depending on the coating film thickness so as to provide a concentration that allows application to a substrate, etc. Generally, the component (S) is used so that the solids concentration of the resist composition falls within the range of 0.1 to 20 mass %, and preferably 0.2 to 15 mass %.

[0377] The resist composition of this embodiment may further contain, if desired, compatible additives such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, or a dye.

[0378] As with the resist composition of the first embodiment, the resist material of the resist composition of this embodiment may be dissolved in component (S), and then impurities and the like may be removed using a polyimide porous film, a polyamideimide porous film, or the like.

[0379] The resist composition of this embodiment described above contains, as the component (D), a compound (D0) that includes a cation (C0). The cation (C0) is a planar low LUMO cation. The compound (D0) containing the cation (C0) is prone to decomposition upon exposure and to loss of its acid diffusion control ability. This improves the sensitivity of the resist composition containing the compound (D0). Furthermore, the cation (C0) has two or more electron-withdrawing groups in the phenyl group, which improves its solubility in the component (S). Furthermore, during development after exposure, its solubility in a developer is improved. This allows a resist composition containing the compound (D0) to reduce defects. As described above, the resist composition of this embodiment can achieve both high sensitivity and reduced defects.

[0380] [Third embodiment] The resist composition of the third embodiment contains a compound (C) as the component (A). The resist composition of the third embodiment contains the component (A) whose solubility in a developer changes under the action of an acid. The component (A) includes a resin component (A0) (hereinafter also referred to as "component (A0)") that has a structural unit (a0) represented by the following general formula (a0-1):

[0381] [ka] [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. M a+ is the cation (C0). 0- is a group containing an anion.

[0382] <Component (A)> In the resist composition of this embodiment, the component (A) includes the component (A0).

[0383] (A0) component The component (A0) is a resin component having the structural unit (a0).

[0384] <Constituent unit (a0)> The structural unit (a0) is a structural unit represented by the general formula (a0-1). 0- Depending on the type of structural unit (a0), it may function as an acid generator or as an acid diffusion controller. Hereinafter, a structural unit (a0) that functions as an acid generator will also be referred to as "structural unit (a0b)." A structural unit (a0) that functions as an acid diffusion controller will also be referred to as "structural unit (a0d)."

[0385] Building blocks (a0b): {cation part} In the general formula (a0-1), M a+ is the cation (C0).

[0386] {anion part} In the general formula (a0-1), 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 is the same as R in the formula (a1-1).

[0387] In the general formula (a0-1), Rx 0- is a group containing an anion. In the structural unit (a0b), Rx 0- is a group containing an anion that generates an acid upon exposure to light. Rx 0- Examples of the anion contained in include an anion represented by the formula (b-1-an), the formula (b-2-an), or the formula (b-3-an).

[0388] Examples of the anionic moiety of the structural unit (a0b) include anionic moieties represented by the following general formula (a0-1-b).

[0389] [ka] [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.] 01 is a single bond or a divalent linking group. 01 represents a single bond, -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, and R' represents a hydrogen atom or a methyl group. 01 If -O-, Ya 01 does not become -CO-. Rx 0b is a group represented by the following general formula (b1-an), general formula (b2-an), or general formula (b3-an).

[0390] [ka] [In the formula, Rx 101 , Rx 104 , and Rx 107 R are each independently a cyclic group which may have a substituent, a chain alkylene group which may have a substituent, or a chain alkenediyl group which may have a substituent.105 , R 106 , and R 108 Rx each independently represents 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. 104 and R 105 R may be bonded to each other to form a ring structure. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. 101 is a divalent linking group containing an oxygen atom or a single bond. 101 ~V 103 are each independently a single bond, an alkylene group, or a fluorinated alkylene group. 101 ~L 102 are each independently a single bond or an oxygen atom. 103 ~L 105 are each independently a single bond, -CO- or -SO2-. * represents La in formula (a0-1-b). 01 represents a bond to the atom.]

[0391] In the formula (a0-1-b), 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 is the same as R in the formula (a1-1).

[0392] In the formula (a0-1-b), Ya 01 is a single bond or a divalent linking group. The divalent linking group is not particularly limited, but examples thereof include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom. Examples of the divalent hydrocarbon group which may have a substituent include Ya in the formula (a2-1). 21 Examples of the divalent linking group containing a hetero atom include the groups represented by the formula (a2-1) above. 21 The same as those mentioned above can be mentioned. Ya 01 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, and more preferably a single bond.

[0393] In the formula (a0-1-b), La 01 is -O-, -COO-, -CON(R')-, -OCO-, -CONHCO- or -CONHCS-. R' represents a hydrogen atom or a methyl group. However, La 01 If -O-, Ya 01 does not become -CO-. La 01 As the alkyl group, —COO— is preferred.

[0394] In the formula (a0-1-b), Rx 0b is a group represented by the general formula (b1-an), (b2-an), or (b3-an).

[0395] A group represented by formula (b1-an) In the formula (b1-an), Rx 101 represents an optionally substituted cyclic group, an optionally substituted chain alkylene group, or an optionally substituted chain alkenediyl group. Rx 101 represents R in the formula (b-1-an). 101 Rx is a group formed by removing one hydrogen atom from 101 As the group, R in the formula (b-1-an) 101 Examples of Rx include groups in which one hydrogen atom has been removed from the groups listed above. 101 Rx is preferably a cyclic group which may have a substituent, and more preferably an alicyclic hydrocarbon group which may have a substituent. 101 is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane or polycycloalkane. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specific examples of which include cyclopentane and cyclohexane. The polycycloalkane is preferably one having 7 to 30 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0396] R 102 , Y 101 , and V 101 represents R in the formula (b-1-an).102 , Y 101 , and V 101 are the same as

[0397] Examples of the group represented by formula (b1-an) include groups represented by any of the following general formulae (b1-an1) to (b1-an3).

[0398] [ka] [In the formula, Rx” 101 Rx" is an aliphatic cyclic group which may have a substituent, a group in which one hydrogen atom has been removed from a monovalent heterocyclic group represented by each of the above chemical formulas (r-hr-1) to (r-hr-6), a group in which one hydrogen atom has been removed from a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), or a chain alkylene group which may have a substituent. 102 Rx" is an aliphatic cyclic group which may have a substituent, a group in which one hydrogen atom has been removed from a fused cyclic group represented by the above formula (r-br-1) or (r-br-2), a group in which one hydrogen atom has been removed from a lactone-containing cyclic group represented by each of the above general formulas (a2-r-1), (a2-r-3) to (a2-r-7), or a group in which one hydrogen atom has been removed from an -SO2- containing cyclic group represented by each of the above general formulas (a5-r-1) to (a5-r-4). 103 V" is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenediyl group which may have a substituent. 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. 102 is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms; each v" is independently an integer of 0 to 3, each q" is independently an integer of 0 to 20, and n" is 0 or 1.

[0399] Rx" in the formula (a-1-an1) 101 is R" in the formula (an-1). 101 It is a group obtained by removing one hydrogen atom from Rx" in the formula (a-1-an2)102 is R" in the formula (an-2). 102 It is a group obtained by removing one hydrogen atom from Rx" in the formula (a-1-an3) 103 is R" in the formula (an-3). 103 It is a group obtained by removing one hydrogen atom from

[0400] V” 10 , R 102 , v″, q″, and n″ are the V″ in the formula (an-1), the formula (an-1), and the formula (an-1). 10 , R 102 , v”, q”, and n”, respectively.

[0401] A group represented by formula (b2-an) In the above formula (b2-an), Rx 104 represents an optionally substituted cyclic group, an optionally substituted chain alkylene group, or an optionally substituted chain alkenediyl group. Rx 104 represents R in the formula (b-2-an). 104 Rx is a group formed by removing one hydrogen atom from 104 As the R in the formula (b-2-an), 104 Examples of such groups include those obtained by removing one hydrogen atom from the groups listed above.

[0402] R 105 , L 101 , L 102 , V 102 , and V 103 represents R in the formula (b-2-an). 105 , L 101 , L 102 , V 102 , and V 103 are the same as

[0403] A group represented by formula (b3-an) In the formula (b3-an), Rx 107 represents an optionally substituted cyclic group, an optionally substituted chain alkylene group, or an optionally substituted chain alkenediyl group. Rx 107 represents R in the formula (b-3-an). 107 Rx is a group formed by removing one hydrogen atom from 107 As the R in the formula (b-3-an), 107 Examples of such groups include those obtained by removing one hydrogen atom from the groups listed above.

[0404] R 106 , R 108 , L 103 , L 104 , and L 105 represents R in the formula (b-3-an). 106 , R 108 , L 103 , L 104 , and L 105 are the same as

[0405] Rx 0b is preferably a group represented by formula (b1-an). 0b is more preferably a group represented by any one of the above formulae (b1-an1) to (b1-an3), further preferably a group represented by either formula (b1-an1) or (b-an2), and particularly preferably a group represented by formula (b1-an1).

[0406] Rx 0b When R is a group represented by the formula (b1-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0407] [ka]

[0408] [ka]

[0409] Rx 0bWhen R is a group represented by the formula (b2-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0410] [ka]

[0411] Rx 0b When R is a group represented by the formula (b3-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0412] [ka]

[0413] [ka]

[0414] <Constituent unit (a0d)> {cation part} In the general formula (a0-1), M a+ is the cation (C0).

[0415] {anion part} In the general formula (a0-1), Rx 0- is a group containing an anion. In the structural unit (a0d), Rx 0- is a group containing an anion that traps acid generated by exposure to light. Rx 0- Examples of the anion contained in include an anion represented by the formula (d-1-an), the formula (d-2-an), or the formula (d-3-an).

[0416] Examples of the anionic moiety of the structural unit (a0d) include anionic moieties represented by the following general formula (a0-1-d).

[0417] [ka] [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.] 01 is a single bond or a divalent linking group. 01 represents a single bond, -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, and R' represents a hydrogen atom or a methyl group. 01 If -O-, Ya 01 does not become -CO-. Rx 0d is a group represented by the following general formula (d1-an), general formula (d2-an), or general formula (d3-an). * represents La in the above formula (a0-1-d). 01 represents a bond to the atom.]

[0418] [ka] [In the formula, Rd 01 ~Rd 03 represents a single bond, a cyclic group which may have a substituent, a chain alkylene group which may have a substituent, or a chain alkenediyl group which may have a substituent. 02 In Rd, the carbon atom adjacent to the S atom does not have a fluorine atom bonded to it. 4 represents 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. 1 is a single bond or a divalent linking group.

[0419] In the formula (a0-1-d), R, Ya 01 , and La 01 represents R and Ya in the formula (a0-1-b). 01 , and La 01 are the same as

[0420] In the formula (a0-1-d), Rx 0d is a group represented by the general formula (d1-an), (d2-an), or (d3-an).

[0421] A group represented by formula (d1-an) In the above formula (d1-an), Rd 01 represents a single bond, a cyclic group which may have a substituent, a chain alkylene group which may have a substituent, or a chain alkenediyl group which may have a substituent. Road 01 is Rd in the formula (d-1-an). 1 A group in which one hydrogen atom has been removed from Rd is preferred. 01 As the group, Rd in the formula (d-1-an) 1 Examples of such groups include those obtained by removing one hydrogen atom from the groups listed above. 01 Rx is preferably a cyclic group which may have a substituent. 101 As the aromatic hydrocarbon group, a group in which two hydrogen atoms have been removed from a monocycloalkane or polycycloalkane, or an aromatic hydrocarbon group (for example, an arylene group) is preferred. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specific examples of which include cyclopentane and cyclohexane. The polycycloalkane is preferably one having 7 to 30 carbon atoms, specific examples of which include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, and a polycyclic structure containing a bicyclooctane skeleton (a polycyclic structure consisting of a bicyclooctane skeleton and another ring structure).

[0422] A group represented by the formula (d2-an) In the above formula (d2-an), Rd 02 represents a single bond, a cyclic group which may have a substituent, a chain alkylene group which may have a substituent, or a chain alkenediyl group which may have a substituent. Road 02 is Rd in the formula (d-2-an). 2A group in which one hydrogen atom has been removed from Rd is preferred. 02 As the Rd in the formula (d-2-an), 2 Examples of such groups include those obtained by removing one hydrogen atom from the groups listed above.

[0423] A group represented by the formula (d3-an) In the formula (d3-an), Rd 03 represents a single bond, a cyclic group which may have a substituent, a chain alkylene group which may have a substituent, or a chain alkenediyl group which may have a substituent. Road 03 is Rd in the formula (d-3-an). 2 A group in which one hydrogen atom has been removed from Rd is preferred. 03 As the group, Rd in the formula (d-3-an) 2 Examples of such groups include those obtained by removing one hydrogen atom from the groups listed above.

[0424] Road 4 and Yd 1 is Rd in the formula (d-3-an). 4 and Yd 1 are the same as

[0425] Rx 0d is preferably a group represented by formula (d1-an) or formula (d2-an), and more preferably a group represented by formula (d1-an).

[0426] Rx 0d When R is a group represented by the formula (d1-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group. m″ is an integer of 0 to 3.

[0427] [ka]

[0428] Rx 0dWhen R is a group represented by the formula (d2-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0429] [ka]

[0430] Rx 0d When R is a group represented by the formula (d2-an), specific examples of the anion moiety of the structural unit (a0) are shown below, but are not limited to these. α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0431] [ka]

[0432] Specific examples of the structural unit (a0) are shown below, but are not limited to these.

[0433] [ka]

[0434] The structural unit (a0) contained in the component (A0) may be of one type, or may be of two or more types. The proportion of the structural unit (a0) in the component (A0) is preferably 3 to 90 mol %, more preferably 5 to 75 mol %, even more preferably 10 to 70 mol %, and particularly preferably 10 to 60 mol %, based on the total (100 mol %) of all structural units constituting the component (A0).The proportion of the structural unit (a0) in the component (A0) may be 100 mol %.

[0435] The component (A0) may be used alone or in combination of two or more types.

[0436] The weight average molecular weight (Mw) of the component (A0) (based on polystyrene standards measured by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and even more preferably 3,000 to 20,000. When the Mw of the component (A0) is less than or equal to the preferred upper limit of this range, the compound has sufficient solubility in a resist solvent for use as a resist, and when it is at least the preferred lower limit of this range, the compound exhibits good dry etching resistance and the cross-sectional shape of the resist pattern. The dispersity (Mw / Mn) of the component (A0) is not particularly limited, but is preferably from 1.0 to 4.0, more preferably from 1.0 to 3.0, and particularly preferably from 1.0 to 2.0.

[0437] Component (A1) The resist composition of this embodiment preferably contains a resin component (A1) (component (A1)) whose solubility in a developer changes under the action of an acid. As the component (A1), the same components as those used in the first embodiment can be used. As the component (A1), one type may be used alone, or two or more types may be used in combination.

[0438] Component (A1) having structural unit (a0) (component (A1-0)) The component (A1) may contain a structural unit (a0). In this case, the component (A1) becomes the component (A0). Hereinafter, a component (A1) containing the structural unit (a0) will also be referred to as the "component (A1-0)."

[0439] The structural unit (a0) contained in the component (A1-0) may be of one type, or may be of two or more types. When the component (A1-0) contains the structural unit (a0), the proportion of the structural unit (a0) in the component (A1-0) is preferably 3 to 50 mol %, more preferably 5 to 40 mol %, even more preferably 10 to 30 mol %, and particularly preferably 15 to 20 mol %, based on the total (100 mol %) of all structural units constituting the component (A1-0). When the proportion of the structural unit (a0) is at least as large as the lower limit of the aforementioned preferred range, lithography properties such as sensitivity and reduced defects are improved. On the other hand, when the proportion of the structural unit (a0) is no greater than the upper limit of the aforementioned preferred range, a balance with other structural units can be achieved, resulting in various favorable lithography properties.

[0440] <Constituent unit (a1)> The component (A1-0) preferably has a structural unit (a1) containing an acid-decomposable group whose polarity increases when acted upon by an acid. As the structural unit (a1), the same structural units as those in the first embodiment can be used.

[0441] The structural unit (a1) contained in the component (A1-0) may be of one type, or may be of two or more types. The proportion of the structural unit (a1) in the component (A1-0) is preferably 5 to 80 mol %, more preferably 10 to 75 mol %, even more preferably 20 to 70 mol %, and particularly preferably 25 to 60 mol %, based on the total (100 mol %) of all structural units constituting the component (A1). When the proportion of the structural unit (a1) is at least as large as the lower limit of the aforementioned preferred range, lithography properties such as sensitivity, resolution, and roughness are improved. On the other hand, when the proportion of the structural unit (a1) is no greater than the upper limit of the aforementioned preferred range, a balance with other structural units can be achieved, and various lithography properties become favorable.

[0442] Other structural units In addition to the structural units (a0) and (a1), the component (A1-0) may also contain other structural units as necessary. Examples of other structural units include the structural units (a2), (a3), (a4), (a10), and (st).

[0443] Building block (a2): The component (A1-0) may also contain a structural unit (a2). As the structural unit (a2), the same structural unit (a2) as in the first embodiment can be used.

[0444] The structural unit (a2) contained in the component (A1-0) may be of one type, or may be of two or more types. When the component (A1-0) contains the structural unit (a2), the proportion of the structural unit (a2) relative to the total (100 mol%) of all structural units constituting the component (A1) is preferably 5 to 60 mol%, more preferably 10 to 60 mol%, even more preferably 20 to 60 mol%, and particularly preferably 30 to 60 mol%. When the proportion of the structural unit (a2) is at least the aforementioned preferred lower limit, the effects of including the structural unit (a2) are fully achieved.On the other hand, when the proportion of the structural unit (a2) is no more than the aforementioned preferred upper limit, a balance with other structural units can be achieved, and various lithography properties become excellent.

[0445] Building block (a3): The component (A1-0) may also contain a structural unit (a3). As the structural unit (a3), the same structural unit (a3) ​​as in the first embodiment can be used.

[0446] The structural unit (a3) ​​contained in the component (A1-0) may be of one type, or may be of two or more types. When the component (A1-0) contains the structural unit (a3), the proportion of the structural unit (a3) ​​relative to the total (100 mol%) of all structural units constituting the component (A1-0) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and even more preferably 5 to 20 mol%. When the proportion of the structural unit (a3) ​​is at least as large as the aforementioned preferable lower limit, the effects of including the structural unit (a3) ​​are fully achieved.On the other hand, when the proportion of the structural unit (a3) ​​is no greater than the aforementioned preferable upper limit, a balance with other structural units can be achieved, and various lithography properties become excellent.

[0447] Building block (a4): The component (A1-0) may also include a structural unit (a4). As the structural unit (a4), the same structural unit (a4) as in the first embodiment can be used.

[0448] The structural unit (a4) contained in the component (A1-0) may be of one type, or may be of two or more types. When the component (A1-0) contains the structural unit (a4), the proportion of the structural unit (a4) relative to the total (100 mol %) of all structural units constituting the component (A1-0) is preferably 1 to 40 mol %, and more preferably 5 to 20 mol %. When the proportion of the structural unit (a4) is at least as large as the aforementioned preferable lower limit, the effects of including the structural unit (a4) are fully achieved.On the other hand, when the proportion of the structural unit (a4) is no greater than the aforementioned preferable upper limit, a balance with other structural units can be achieved, and various lithography properties become excellent.

[0449] Building block (a10): The component (A1-0) preferably includes a structural unit (a10). As the structural unit (a10), the same structural unit (a10) as in the first embodiment can be used.

[0450] The structural unit (a10) contained in the component (A1-0) may be of one type, or may be of two or more types. When the component (A1-0) contains the structural unit (a10), the proportion of the structural unit (a10) relative to the total (100 mol%) of all structural units constituting the component (A1-0) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, even more preferably 30 to 60 mol%, and particularly preferably 30 to 55 mol%. When the proportion of the structural unit (a10) is at least as large as the aforementioned preferable lower limit, sensitivity is likely to be improved. On the other hand, when the proportion of the structural unit (a10) is no greater than the aforementioned preferable upper limit, a balance with other structural units can be achieved, and various lithography properties become favorable.

[0451] Units (st): The component (A1-0) may have a structural unit (st). As the structural unit (st), the same structural unit (st) as in the first embodiment can be used.

[0452] The structural unit (st) contained in the component (A1-0) may be of one type, or two or more types. When the component (A1-0) contains the structural unit (st), the proportion of the structural unit (st) relative to the total (100 mol%) of all structural units constituting the component (A1-0) is preferably 1 to 30 mol%, and more preferably 3 to 20 mol%. When the proportion of the structural unit (st) is at least the above-mentioned preferable lower limit, the effects of including the structural unit (st) are fully obtained. On the other hand, when the proportion of the structural unit (st) is no more than the above-mentioned preferable upper limit, a balance with other structural units can be achieved, and various lithography properties become excellent.

[0453] The component (A1-0) may be used alone or in combination of two or more types. Examples of the component (A1-0) include polymeric compounds having a repeating structure of the structural unit (a0) and the structural unit (a1), and preferably polymeric compounds having a repeating structure of the structural unit (a0), the structural unit (a1), and the structural unit (a10). Among the above, suitable examples of the component (A1-0) include polymeric compounds comprising a repeating structure of the structural unit (a0) and the structural unit (a1); and polymeric compounds comprising a repeating structure of the structural unit (a0), the structural unit (a1), and the structural unit (a10).

[0454] The weight average molecular weight (Mw) of the component (A1-0) (based on polystyrene standards measured by gel permeation chromatography (GPC)) is not particularly limited, but is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and even more preferably 3,000 to 20,000. When the Mw of the component (A1-0) is at most the upper limit of this preferred range, the compound has sufficient solubility in a resist solvent for use as a resist, and when it is at least the lower limit of this preferred range, the compound exhibits good dry etching resistance and the cross-sectional shape of the resist pattern. The dispersity (Mw / Mn) of the component (A1) is not particularly limited, but is preferably from 1.0 to 4.0, more preferably from 1.0 to 3.0, and particularly preferably from 1.0 to 2.0.

[0455] ·(A2) Component The resist composition of this embodiment may contain a component (A2) as the component (A). As the component (A2), the same compounds as the component (A2) in the first embodiment can be used.

[0456] The proportion of component (A1-0) within component (A), relative to the total mass of component (A), is preferably at least 25 mass%, more preferably at least 50 mass%, even more preferably at least 75 mass%, and may even be 100 mass%. A proportion of 25 mass% or greater facilitates the formation of a resist pattern that exhibits excellent lithography properties, such as high sensitivity, resolution, improved roughness, and reduced defects.

[0457] The amount of the component (A) in the resist composition of this embodiment may be adjusted depending on factors such as the thickness of the resist film to be formed.

[0458] <Other ingredients> The resist composition of this embodiment may further contain other components in addition to the component (A). Examples of other components include the following components (B), (D), (E), (F), and (S).

[0459] ≪(B) Component≫ The resist composition of this embodiment may contain a component (B). The component (B) can be the same as the component (B1) in the first embodiment.

[0460] In the resist composition of this embodiment, the component (B) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (B), the amount of the component (B) relative to 100 parts by mass of the component (A) is preferably 5 to 40 parts by mass, more preferably 10 to 40 parts by mass, even more preferably 12 to 40 parts by mass, and particularly preferably 15 to 35 parts by mass. By ensuring that the amount of component (B) falls within the above-mentioned preferred range, sufficient pattern formation is achieved. Furthermore, when the components of the resist composition are dissolved in an organic solvent, a homogeneous solution is easily obtained, and the storage stability of the resist composition is also favorable.

[0461] ≪(D) ​​Component≫ The resist composition of this embodiment preferably contains a component (D). The component (D) can be the same as the component (D) in the first embodiment.

[0462] In the resist composition of this embodiment, the component (D) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (D), the amount of the component (D) relative to 100 parts by mass of the component (A) is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 8 parts by mass. When the amount of component (D) is at least the above-mentioned preferable lower limit, good lithography properties and good resist pattern shape are likely to be obtained, while when the amount of component (D) is no more than the above-mentioned preferable upper limit, good sensitivity can be maintained.

[0463] ≪(E) Component≫ The resist composition of this embodiment may contain a component (E). The component (E) can be the same as the component (E) in the first embodiment. In the resist composition of this embodiment, the component (E) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (E), the amount of the component (E) relative to 100 parts by mass of the component (A) is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass. By ensuring that the amount is within this range, the sensitivity, lithography properties, and the like are improved.

[0464] <(F) Component> The resist composition of this embodiment may contain a component (F). The component (F) can be the same as the component (E) in the first embodiment. In the resist composition of this embodiment, the component (F) may be used either as a single type, or in combination of two or more types. When the resist composition of this embodiment contains the component (F), the amount of the component (F) relative to 100 parts by mass of the component (A) is preferably 0.5 to 10 parts by mass, and more preferably 1 to 10 parts by mass.

[0465] ≪(S) component≫ The component (S) can be the same as the component (S) in the first embodiment. There are no particular restrictions on the amount of component (S) used, and it is set appropriately depending on the coating film thickness so as to provide a concentration that allows application to a substrate, etc. Generally, the component (S) is used so that the solids concentration of the resist composition falls within the range of 0.1 to 20 mass %, and preferably 0.2 to 15 mass %.

[0466] The resist composition of this embodiment may further contain, if desired, compatible additives such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, or a dye.

[0467] As with the resist composition of the first embodiment, the resist material of the resist composition of this embodiment may be dissolved in component (S), and then impurities and the like may be removed using a polyimide porous film, a polyamideimide porous film, or the like.

[0468] The resist composition of this embodiment described above contains, as the component (A), a resin component (A0) that includes a cation (C0). The cation (C0) is a low LUMO cation with a planar structure. The resin component (A0) contains a structural unit (a0) that generates acid upon exposure. By including the cation (C0), the structural unit (a0) improves the efficiency of acid generation upon exposure, and as a result, the sensitivity of a resist composition containing the resin component (A0) is improved. Furthermore, the cation (C0) has two or more electron-withdrawing groups on the phenyl group, which improves its solubility in the component (S). Furthermore, during development after exposure, its solubility in the developer is improved. This allows the resist composition containing the resin component (A0) to reduce defects. As described above, the resist composition of this embodiment can achieve both high sensitivity and reduced defects.

[0469] [Fourth to Seventh Embodiments] The resist composition of the fourth embodiment contains compound (C) as the component (B) and the component (D). That is, the resist composition of the fourth embodiment contains the component (B0) and the component (D0). The resist composition of the fourth embodiment preferably contains the component (A1), the component (B0), and the component (D0). The resist composition of the fourth embodiment may contain the following other components: a component (E), a component (F), and a component (S). In the resist composition of the fourth embodiment, the content of each component can be the same as in the first to third embodiments.

[0470] The resist composition of the fifth embodiment contains compound (C) as the component (B) and the component (A). That is, the resist composition of the fifth embodiment contains the component (B0) and the component (A0). The component (A0) may contain either the structural unit (a0b) or the structural unit (a0d), or may contain both, but preferably contains the structural unit (a0d). The resist composition of the fifth embodiment preferably contains the component (A1-0) and the component (B0). The resist composition of the fifth embodiment may contain the following other components: a component (D), a component (E), a component (F), and a component (S). In the resist composition of the fifth embodiment, the content of each component can be the same as in the first to third embodiments.

[0471] The resist composition of the sixth embodiment contains compound (C) as the component (D) and the component (A). That is, the resist composition of the sixth embodiment contains the component (D0) and the component (A0). The component (A0) may contain either the structural unit (a0b) or the structural unit (a0d), or may contain both, but preferably contains the structural unit (a0b). The resist composition of the sixth embodiment preferably contains the component (A1-0) and the component (D0). The resist composition of the sixth embodiment may contain the following other components: the component (B), the component (E), the component (F), and the component (S). In the resist composition of the sixth embodiment, the content of each component can be the same as in the first to third embodiments.

[0472] The resist composition of the seventh embodiment contains compound (C) as the components (B), (D), and (A). That is, the resist composition of the seventh embodiment contains the component (B0), the component (D0), and the component (A0). The component (A0) may contain either the structural unit (a0b) or the structural unit (a0d), or may contain both. The resist composition of the seventh embodiment preferably contains the component (B0), the component (A1-0), and the component (D0). The resist composition of the seventh embodiment may contain the following other components: the component (E), the component (F), and the component (S). In the resist composition of the seventh embodiment, the content of each component can be the same as in the first to third embodiments.

[0473] (Method for forming a resist pattern) A method for forming a resist pattern according to a second aspect of the present invention is a method comprising the steps of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film to light, and developing the exposed resist film to form a resist pattern. One embodiment of the resist pattern forming method is, for example, a resist pattern forming method carried out as follows.

[0474] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and then baked (post-apply bake (PAB)) at a temperature of, for example, 80 to 150°C for 40 to 120 seconds, preferably 60 to 90 seconds, to form a resist film. Next, the resist film is selectively exposed using an exposure device such as an electron beam lithography device or an ArF exposure device, either through a mask (mask pattern) on which a predetermined pattern has been formed, or by direct irradiation with an electron beam without using a mask pattern, and then baked (post-exposure bake (PEB)) for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of 80 to 150°C. Next, the resist film is developed using an alkaline developer in the case of an alkaline development process, or a developer containing an organic solvent (organic developer) in the case of a solvent development process.

[0475] After the development process, a rinse process is preferably carried out. In the case of an alkaline development process, the rinse process is preferably a water rinse using pure water, and in the case of a solvent development process, it is preferable to use a rinse solution containing an organic solvent. In the case of a solvent development process, the developing treatment or rinsing treatment may be followed by a treatment of removing the developing solution or rinsing solution adhering to the pattern using a supercritical fluid. After the development treatment or rinsing treatment, the film is dried. In some cases, a baking treatment (post-baking) may be performed after the development treatment. In this manner, a resist pattern can be formed.

[0476] The support is not particularly limited, and conventionally known supports can be used, such as substrates for electronic components and those on which a predetermined wiring pattern is formed. More specifically, examples include silicon wafers, substrates made of metals such as copper, chromium, iron, and aluminum, and glass substrates. Materials that can be used for the wiring pattern include copper, aluminum, nickel, and gold. The support may also be a substrate as described above on which an inorganic and / or organic film is provided. Examples of inorganic films include inorganic anti-reflective coatings (inorganic BARCs). Examples of organic films include organic anti-reflective coatings (organic BARCs) and organic films such as lower organic films in multilayer resist methods. Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are provided on a substrate, and the lower organic film is patterned using the resist pattern formed on the upper resist film as a mask, and it is said to be able to form patterns with a high aspect ratio. In other words, with the multilayer resist method, the required thickness can be ensured by the lower organic film, so the resist film can be made thinner and fine patterns with a high aspect ratio can be formed. Multilayer resist methods are basically divided into a two-layer structure consisting of an upper resist film and a lower organic film (two-layer resist method), and a three-layer structure consisting of three or more layers with one or more intermediate layers (such as a metal thin film) between the upper resist film and the lower organic film (three-layer resist method).

[0477] The wavelength used for exposure is not particularly limited, and radiation such as an ArF excimer laser, a KrF excimer laser, an F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, soft X-rays, etc. The resist composition is highly useful for KrF excimer lasers, ArF excimer lasers, EB, or EUV, and is even more useful for ArF excimer lasers.

[0478] The exposure method for the resist film may be a normal exposure (dry exposure) performed in air or an inert gas such as nitrogen, or may be liquid immersion lithography, but liquid immersion lithography is preferred. Immersion exposure is an exposure method in which the space between the resist film and the lowest lens of the exposure device is filled with a solvent (immersion medium) that has a refractive index greater than that of air, and then exposure (immersion exposure) is performed in that state. The immersion medium is preferably a solvent having a refractive index greater than that of air and less than that of the resist film to be exposed. The refractive index of such a solvent is not particularly limited as long as it is within the above range. Examples of solvents having a refractive index greater than that of air and smaller than that of the resist film include water, fluorine-based inert liquids, silicon-based solvents, and hydrocarbon-based solvents. Specific examples of the fluorine-based inert liquid include liquids containing as a main component a fluorine-based compound such as C3HCl2F5, C4F9OCH3, C4F9OC2H5, or C5H3F7, and preferably have a boiling point of 70 to 180° C., more preferably 80 to 160° C. If the fluorine-based inert liquid has a boiling point within the above range, it is preferable because the medium used for immersion can be removed simply and easily after exposure is completed. As the fluorine-based inert liquid, particularly preferred are perfluoroalkyl compounds in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms, specifically perfluoroalkyl ether compounds and perfluoroalkylamine compounds. More specifically, the perfluoroalkyl ether compound may include perfluoro(2-butyl-tetrahydrofuran) (boiling point: 102°C), and the perfluoroalkylamine compound may include perfluorotributylamine (boiling point: 174°C). As the liquid immersion medium, water is preferably used from the viewpoints of cost, safety, environmental issues, versatility, and the like.

[0479] An example of an alkaline developer used in the development treatment in the alkaline development process is a 0.1 to 10 mass % aqueous solution of tetramethylammonium hydroxide (TMAH). The organic solvent contained in the organic developer used in the development treatment in the solvent development process may be any organic solvent capable of dissolving component (A) (component (A) before exposure), and may be appropriately selected from known organic solvents. Specific examples include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents. Ketone-based solvents are organic solvents that contain CC(=O)-C in their structure. Ester-based solvents are organic solvents that contain CC(=O)-OC in their structure. Alcohol-based solvents are organic solvents that contain an alcoholic hydroxyl group in their structure. "Alcoholic hydroxyl group" means a hydroxyl group bonded to a carbon atom of an aliphatic hydrocarbon group. Nitrile-based solvents are organic solvents that contain a nitrile group in their structure. Amide-based solvents are organic solvents that contain an amide group in their structure. Ether-based solvents are organic solvents that contain COC in their structure. Some organic solvents contain multiple types of functional groups that characterize the above-mentioned solvents in their structure, and in such cases, the term "organic solvent" refers to any solvent type containing the functional groups possessed by the organic solvent. For example, diethylene glycol monomethyl ether is considered to be both an alcohol-based solvent and an ether-based solvent in the above classification. The hydrocarbon solvent is a hydrocarbon solvent that is composed of a hydrocarbon that may be halogenated and has no substituents other than halogen atoms, and the halogen atoms are preferably fluorine atoms. Of the above, the organic solvent contained in the organic developer is preferably a polar solvent, and more preferably a ketone solvent, an ester solvent, a nitrile solvent, or the like.

[0480] Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), etc. Among these, methyl amyl ketone (2-heptanone) is preferred as the ketone solvent.

[0481] Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl ether ... Dibutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate Examples of the ester solvent include butyl acetate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl 3-methoxypropionate, etc. Among these, butyl acetate is preferred as the ester solvent.

[0482] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0483] Known additives can be blended into the organic developer as needed. Examples of such additives include surfactants. The surfactant is not particularly limited, but examples include ionic or nonionic fluorine-based and / or silicon-based surfactants. Nonionic surfactants are preferred, and nonionic fluorine-based surfactants or nonionic silicon-based surfactants are more preferred. When a surfactant is added, the amount added is usually 0.001 to 5 mass %, preferably 0.005 to 2 mass %, and more preferably 0.01 to 0.5 mass %, based on the total amount of the organic developer.

[0484] The development process can be carried out by a known development method, such as a method of immersing the support in a developer for a certain period of time (dip method), a method of piling up the developer on the surface of the support by surface tension and leaving it standing for a certain period of time (puddle method), a method of spraying the developer onto the surface of the support (spray method), or a method of continuously applying the developer while scanning a developer application nozzle at a constant speed onto a support rotating at a constant speed (dynamic dispense method).

[0485] The organic solvent contained in the rinse solution used in the rinsing treatment after development in the solvent development process can be appropriately selected from the organic solvents listed above as organic solvents used in the organic developer, and can be one that does not easily dissolve the resist pattern. Usually, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents, and ether solvents is used. Among these, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, and amide solvents is preferred, at least one solvent selected from alcohol solvents and ester solvents is more preferred, and alcohol solvents are particularly preferred. The alcohol-based solvent used in the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be linear, branched, or cyclic. Specific examples include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. Of these, 1-hexanol, 2-heptanol, and 2-hexanol are preferred, and 1-hexanol and 2-hexanol are more preferred. These organic solvents may be used alone or in combination of two or more. They may also be used in combination with other organic solvents or water. However, taking into consideration the development characteristics, the amount of water in the rinse solution is preferably 30% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less, based on the total amount of the rinse solution. The rinse solution may contain known additives as needed. Examples of such additives include surfactants. Examples of surfactants include those described above, with nonionic surfactants being preferred, and nonionic fluorine-based surfactants or nonionic silicone-based surfactants being more preferred. When a surfactant is added, the amount added is usually 0.001 to 5 mass %, preferably 0.005 to 2 mass %, and more preferably 0.01 to 0.5 mass %, based on the total amount of the rinse liquid.

[0486] The rinse treatment (cleaning treatment) using a rinse solution can be carried out by a known rinse method, such as a method of continuously applying the rinse solution onto a support rotating at a constant speed (spin coating method), a method of immersing the support in the rinse solution for a certain period of time (dipping method), or a method of spraying the rinse solution onto the surface of the support (spray method).

[0487] According to the method of forming a resist pattern of this embodiment described above, the resist composition of the first aspect is used, so a resist pattern with reduced defects can be formed.

[0488] (compound) The compound according to the third aspect of the present invention is a compound represented by the following general formula (M0) (hereinafter also referred to as "compound (M0)").

[0489] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same or different. X - is the counter anion.

[0490] {cation part} The cation moiety is the same as the cation (C0) represented by the general formula (c0) above.

[0491] {anion part} X - is the counter anion. X - Examples of the anion moiety include those exemplified as the anion moiety of the compound represented by general formula (b0), those exemplified as the anion moiety of the compound represented by general formula (d0), and those exemplified as the anion moiety of the structural unit represented by general formula (a0-1).

[0492] <Method of manufacturing the compound> The compound (M0) can be produced by a known method. An example of a method for producing the compound (M0) is a production method including the following first and second steps.

[0493] The compounds used in each step may be commercially available or synthesized. The solvent used in each reaction of Step 1 and Step 2 can be one that dissolves the compounds used in each step but does not react with these compounds, such as dichloromethane, dichloroethane, chloroform, tetrahydrofuran, N,N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, acetonitrile, and propionitrile.

[0494] 1st step: In the first step, compound (I), compound (II), and TMS-X″ are mixed in a solvent and reacted to obtain compound (pre). The solvent in the first step may be, for example, tetrahydrofuran. The reaction temperature is, for example, 0 to 50° C., preferably 10 to 40° C. The reaction time can be appropriately set depending on the reactivity and amount of the compound used, etc. The reaction time is, for example, from 10 minutes to 24 hours, preferably from 10 minutes to 12 hours.

[0495] After a desired reaction time has elapsed, the reaction may be stopped by adding water to the reaction solution. After completion of the reaction, the compound (pre) may be purified by solvent extraction, vacuum concentration, crystallization, or the like. Examples of solvents used for solvent extraction include dichloromethane. Examples of solvents used for crystallization include a mixed solvent of dichloromethane and tert-butyl ethyl ether.

[0496] [ka] [where, X 01 , X 02 , R 01 ~R 03 , nx1, nx2, and n1 to n3 are the same as those in the formula (M0). h represents a halogen atom. TMS represents a trimethylsilyl group. X” - represents the counter anion in the compound (pre).

[0497] In the reaction scheme, X h Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. X” - The counter anion in - , Cl - , CF3SO3 - Examples of the compound represented by TMS-X" include trimethylsilyl trifluoromethanesulfonate (TMSOTf).

[0498] Second step: In the second step, the compound (pre) and the compound (III) for salt exchange are mixed in a solvent to carry out a salt exchange reaction, thereby obtaining the compound (M0). The solvent in the second step may be, for example, dichloromethane. The reaction temperature is, for example, 0 to 100° C., preferably 0 to 50° C. The reaction time can be appropriately set depending on the reactivity and amount of the compound used, etc. The reaction time is, for example, from 10 minutes to 24 hours, preferably from 10 minutes to 12 hours.

[0499] After completion of the salt exchange reaction, compound (M0) may be isolated and / or purified. A known method can be used for isolating and / or purifying compound (M0). Examples of isolation and / or purification methods include concentration, solvent extraction, distillation, crystallization, recrystallization, and chromatography, and these methods can be used in appropriate combinations.

[0500] [ka] [where, X 01 , X 02 , R 01 ~R 03 , nx1, nx2, n1~n3, and X - are the same as those in the formula (MO). - represents a counter anion in the compound (pre). + represents an ammonium cation.]

[0501] In the above reaction scheme, M' + The ammonium cation in M' includes organic ammonium cations, and a quaternary ammonium cation is preferred. + The ammonium cation in the formula (III) can be appropriately selected depending on the counter anion in the compound (III).

[0502] The structure of the compound obtained as above is 1 H-nuclear magnetic resonance (NMR) spectroscopy, 13 C-NMR spectroscopy, 19 Identification can be achieved by common organic analysis methods such as F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass spectrometry (MS), elemental analysis, and X-ray crystal diffraction.

[0503] Specific examples of the compound (M0) include the same as those given as specific examples of the compound (B0) or the compound (D0).

[0504] (acid generator) The acid generator according to the fourth aspect of the present invention includes a compound represented by the following general formula (B0).

[0505] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same or different. - is the counter anion.

[0506] {cation part} The cation moiety is the same as the cation (C0) represented by the general formula (c0) above.

[0507] {anion part} Xb - is the counter anion. Xb - represents Xb in the general formula (b0). - is the same as

[0508] Specific examples of the compound represented by general formula (B0) include the same compounds as those given as specific examples of the compound (B0) above.

[0509] The acid generator of this embodiment includes a compound represented by general formula (B0). The cation moiety of this compound is a planar low LUMO cation, which provides high acid generation efficiency. Therefore, the resist composition containing the acid generator of this embodiment exhibits improved sensitivity. Furthermore, the compound has two or more electron-withdrawing groups in the phenyl group in the cationic moiety, which improves solubility in the component (S) when used in a resist composition. Furthermore, during development after exposure, solubility in a developer is improved. As a result, a resist composition containing the acid generator of this embodiment can reduce defects. As described above, the acid generator of this embodiment can achieve both increased sensitivity and reduced defects in the resist composition.

[0510] (acid diffusion controller) The acid diffusion controller according to the fifth aspect of the present invention includes a compound represented by the following general formula (D0).

[0511] [ka] [where, X 01 is an electron-withdrawing group, and X 02 is X 01 is an electron-withdrawing group different from R 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same or different. - is the counter anion.

[0512] {cation part} The cation moiety is the same as the cation (C0) represented by the general formula (c0) above.

[0513] {anion part} Xd - is the counter anion. Xd - represents Xd in the general formula (d0). - is the same as

[0514] Specific examples of the compound represented by general formula (D0) include the same as those given as specific examples of the compound (D0) above.

[0515] The acid diffusion controller of this embodiment includes a compound represented by general formula (D0). The cation moiety of this compound is a planar low LUMO cation, which is easily decomposed by exposure and loses its acid diffusion control ability. Therefore, the resist composition containing the acid diffusion controller of this embodiment has improved sensitivity. Furthermore, the compound has two or more electron-withdrawing groups in the phenyl group in the cationic moiety, which improves solubility in the component (S) when used in a resist composition. Furthermore, during development after exposure, the compound has improved solubility in a developer. This allows a resist composition containing the acid diffusion controller of this embodiment to reduce defects. As described above, the acid diffusion controller of this embodiment can achieve both increased sensitivity and reduced defects in the resist composition.

[0516] (polymer compound) The polymer compound according to the sixth aspect of the present invention has a constitutional unit represented by the following general formula (A0-1).

[0517] [ka] [In the formula, R is a hydrogen atom, a carbon atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.] 0 is a group containing an anion. 01 is an electron-withdrawing group, and X 02 is X01 R is an electron-withdrawing group different from 01 is an electron-donating group. 02 and R 03 are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X 01 may be the same or different. When nx2 is 2 or more, there are multiple X 02 may be the same or different. When n1 is 2 or more, multiple R 01 may be the same or different. When n2 is 2 or more, multiple R 02 may be the same or different. When n3 is 2 or more, multiple R 03 may be the same as or different from each other.]

[0518] {cation part} The cation moiety is the same as the cation (C0) represented by the general formula (c0) above.

[0519] {anion part} Rx 0 is a group containing an anion. 0 represents Rx in the general formula (a0-1). 0 is the same as

[0520] Specific examples of the structural unit represented by general formula (A0-1) include the same as those given above as specific examples of the structural unit (a0).

[0521] Examples of the polymer compound of this embodiment include those similar to the resin component (A-0) or the resin component (A1-0).

[0522] The polymer compound of this embodiment includes a structural unit represented by general formula (A0-1). The cation moiety of this structural unit is a planar low LUMO cation, which is easily decomposed by exposure. Therefore, when it functions as an acid generator, it has high acid generation efficiency. Furthermore, when it functions as an acid diffusion controller, it is likely to lose its acid diffusion control ability by exposure. Therefore, a resist composition containing the polymer compound of this embodiment has improved sensitivity. Furthermore, the structural unit has two or more electron-withdrawing groups in the phenyl group in the cationic moiety, which improves solubility in the component (S) when used in a resist composition. Furthermore, during development after exposure, solubility in a developer is improved. As a result, a resist composition containing the acid diffusion controller of this embodiment can reduce defects. As described above, the polymer compound of this embodiment can achieve both increased sensitivity and reduced defects in the resist composition.

[0523] <Method of manufacturing polymer compounds> The polymer compound of this embodiment can be obtained by polymerizing a monomer that derives the structural unit (a0) and, if necessary, a monomer that derives other structural units (structural units (a1) to (a4), (a10), (st), etc.) by known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). [Example]

[0524] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0525] <Production of Compounds> (Manufacturing example B1) Manufacturing example B1-1: Magnesium (4.2 g) and tetrahydrofuran (19 g) were stirred at 50°C, and a solution of compound (1) (38 g) in tetrahydrofuran (THF) (75 g) was added dropwise at the same temperature. After the addition was complete, the mixture was stirred for 2 hours and cooled to room temperature. Tetrahydrofuran (75 g) was added to obtain a THF solution of compound (1') (Solution 1). Dibenzothiophene 5-oxide (10 g) and THF (75 g) were placed in a separate container and stirred at room temperature. Trimethylsilyl trifluoromethanesulfonate (TMSOTf) (63 g) and Solution 1 were added dropwise to the mixture. After the addition was complete, the reaction was continued at room temperature for 1 hour to complete the reaction. Dichloromethane (100 g) and water (100 g) were then added, and the mixture was stirred for 30 minutes. The aqueous layer was then removed. The organic layer was washed three times with ultrapure water (100 g) and then concentrated under reduced pressure. The concentrated residue was crystallized from dichloromethane / tert-butyl methyl ether to obtain precursor (pre-1) (6.2 g) as a white solid. - " represents trifluoromethanesulfonate.

[0526] [ka]

[0527] Manufacturing example B1-2: Dichloromethane (50 g) and water (50 g) were added to precursor (pre-1) (6.2 g) and compound (B-an1) (5.8 g), and the mixture was thoroughly stirred and then separated. The organic layer was washed with 1% hydrochloric acid (50 g) and then with purified water (50 g) three times. Diethyl ether (150 g) was added to the organic layer, and the precipitated crystals were collected by vacuum filtration. The obtained crystals were dried under vacuum to obtain compound (B0-1) (17.1 g).

[0528] [ka]

[0529] (Manufacturing examples B2~B12) Precursors (pre-2) to (pre-12) were obtained in the same manner as in Production Example B1-1, except that compound (1) was replaced with compounds (2) to (12), respectively. Compounds (B0-2) to (B0-12) were obtained in the same manner as in Production Example B1-2, except that precursor (pre-1) was changed to precursors (pre-2) to (pre-12), respectively.

[0530] [ka]

[0531] [ka]

[0532] [ka]

[0533] [ka]

[0534] [ka]

[0535] (Manufacturing examples B13~B16) Compounds (B0-13) to (B0-16) were obtained in the same manner as in Production Example B1, except that compound (B-an1) was replaced with compounds (B-an13) to (B-an16), respectively.

[0536] [ka]

[0537] [ka]

[0538] (Manufacturing example D1) Dichloromethane (50 g) and water (50 g) were added to the precursor (pre-1) (36.2 g) and compound (D-an1) (5.2 g), and the mixture was thoroughly stirred and then separated. The organic layer was washed with 1% hydrochloric acid (50 g) and then with purified water (50 g) three times. Diethyl ether (150 g) was added to the organic layer, and the precipitated crystals were collected by vacuum filtration. The obtained crystals were dried under vacuum to obtain compound (D0-1) (5.9 g).

[0539] [ka]

[0540] (Manufacturing examples D2~D12) Compounds (D0-2) to (D0-12) were obtained in the same manner as in Production Example D1, except that precursor (pre-1) was changed to precursors (pre-2) to (pre-12), respectively.

[0541] [ka]

[0542] [ka]

[0543] [ka]

[0544] (Manufacturing Examples D13-D14) Compounds (D0-13) to (D0-14) were obtained in the same manner as in Production Example D1, except that compound (D-an1) was changed to compounds (D-an13) to (D-an14), respectively.

[0545] [ka]

[0546] [ka]

[0547] Tables 1 to 7 show the NMR measurement results of the compounds (B0-1) to (B0-16) and the compounds (D0-1) to (D0-14) produced in the above Production Examples.

[0548] [Table 1]

[0549] [Table 2]

[0550] [Table 3]

[0551] [Table 4]

[0552] [Table 5]

[0553] [Table 6]

[0554] [Table 7]

[0555] <Production of polymer compounds> The polymer compounds (A1-01) to (A1-02) used in this example were each obtained by radical polymerization using monomers that derive the structural units constituting each polymer compound in a predetermined molar ratio. The weight average molecular weight (Mw) and molecular weight dispersity (Mw / Mn) of each of the obtained polymer compounds were determined by GPC measurement (converted to standard polystyrene). The copolymer composition ratio (the ratio (molar ratio) of each structural unit in the structural formula) of each polymer compound obtained was determined by carbon-13 nuclear magnetic resonance spectroscopy (600 MHz 13 C-NMR).

[0556] [ka]

[0557] Polymer compound (A1-01): Weight average molecular weight (Mw) 9500, molecular weight dispersity (Mw / Mn) 1.72, l / m / n=55 / 30 / 15. Polymer compound (A1-02): Weight average molecular weight (Mw) 9500, molecular weight dispersity (Mw / Mn) 1.75, l / m / n=55 / 30 / 15.

[0558] <Preparation of Resist Composition> (Examples 1 to 60, Comparative Examples 1 to 24) The components shown in Tables 8 to 19 were mixed and dissolved to prepare the resist compositions of each example.

[0559] [Table 8]

[0560] [Table 9]

[0561] [Table 10]

[0562] [Table 11]

[0563] [Table 12]

[0564] [Table 13]

[0565] [Table 14]

[0566] [Table 15]

[0567] [Table 16]

[0568] [Table 17]

[0569] [Table 18]

[0570] [Table 19]

[0571] In Tables 8 to 19, the abbreviations have the following meanings: The numbers in brackets [ ] are the blend amounts (parts by mass). (A1)-01 to (A1)-02: The above polymer compounds (A1-01) to (A1-02). (A1)-1 to (A1)-5: The following polymer compounds (A1-1) to (A1-5). Polymer compound (A1-1): Weight average molecular weight (Mw) 5500, molecular weight dispersity (Mw / Mn) 1.76, l / m=40 / 60. Polymer compound (A1-2): Weight average molecular weight (Mw) 5500, molecular weight dispersity (Mw / Mn) 1.66, l / m=40 / 60. Polymer compound (A1-3): Weight average molecular weight (Mw) 5500, molecular weight dispersity (Mw / Mn) 1.72, l / m / n=30 / 60 / 10. Polymer compound (A1-4): Weight average molecular weight (Mw) 9500, molecular weight dispersity (Mw / Mn) 1.72, l / m / n=55 / 30 / 15. Polymer compound (A1-5): Weight average molecular weight (Mw) 9500, molecular weight dispersity (Mw / Mn) 1.75, l / m / n=55 / 30 / 15.

[0572] [ka]

[0573] [ka]

[0574] (B0)-1 to (B0)-16: Acid generators consisting of the above compounds (B0-1) to (B0-16).

[0575] (B1)-1 to (B1)-14: Acid generators consisting of the following compounds (B1-1) to (B1-14).

[0576] [ka]

[0577] [ka]

[0578] [ka]

[0579] [ka]

[0580] (D0)-1 to (D0)-14: Photodegradable bases consisting of the above compounds (D0-1) to (D0-14).

[0581] (D1)-1 to (D1)-13: Acid diffusion controllers consisting of compounds represented by the following chemical formulas (D1-1) to (D1-13).

[0582] [ka]

[0583] [ka]

[0584] [ka]

[0585] [ka]

[0586] (S)-1: A mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether=60 / 40 (mass ratio).

[0587] <Formation of resist pattern> Each resist composition of each example was applied using a spinner onto an 8-inch silicon substrate that had been treated with hexamethyldisilazane (HMDS), and then pre-baked (PAB) on a hot plate at 110°C for 60 seconds, followed by drying to form a resist film with a thickness of 50 nm. Next, the resist film was subjected to exposure to light using an electron beam lithography system JEOL-JBX-9300FS (manufactured by JEOL Ltd.) at an acceleration voltage of 100 kV to form a 1:1 line and space pattern (hereinafter referred to as "LS pattern") with a target size of 50 nm line width, followed by post-exposure baking (PEB) at 100°C for 60 seconds. Next, alkaline development was performed for 60 seconds using a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23°C. This was followed by a 15-second rinse using pure water. As a result, a 1:1 LS pattern with a line width of 50 nm was formed.

[0588] [Evaluation of optimal exposure (Eop)] The optimum exposure dose Eop (mJ / cm) for forming a target size LS pattern by the above <Resist pattern formation> 2 This is called "Eop (mJ / cm 2 )" are shown in Tables 13 to 24.

[0589] [Defect Rating] Each resist composition was applied using a spinner to an 8-inch silicon substrate that had been treated with hexamethyldisilazane (HMDS), and then pre-baked (PAB) on a hot plate at 110°C for 60 seconds, followed by drying to form a resist coating film with a thickness of 50 nm. The number of foreign particles / defects in this coating film was measured using a Surfscan SP2 (product name) manufactured by KLA-Tencor Corporation. The number of foreign particles / defects of 80 nm or less present on the coating film surface was calculated relative to the number in Comparative Example 1, which was set to 1.0, and evaluated according to the following evaluation criteria. The results are shown as "defects" in Tables 20 to 31. (Evaluation criteria) ◎: 0.2 or less ○: 0.2~0.5 △: 0.5~1.0 ×: over 1.0

[0590] Table 20

[0591] Table 21

[0592] Table 22

[0593] Table 23

[0594] Table 24

[0595] Table 25

[0596] Table 26

[0597] Table 27

[0598] Table 28

[0599] Table 29

[0600] Table 30

[0601] [Table 31]

[0602] As shown in Tables 20 to 31, it was confirmed that the resist compositions of the examples were superior in both sensitivity and defect reduction compared to the resist compositions of the comparative examples.

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, Contains a compound containing a cation (C0) represented by the following general formula (c0): Resist composition. 【Chemistry 1】 [In the formula, X ０１ and X 02 are each independently an acyl group, a mesyl group, a fluorine atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, or a thiocarbonyl group, and are different from each other. ０１ is an electron donating group. ０２ and R ０３ are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X ０１ may be the same or different. When nx2 is 2 or more, a plurality of X ０２ may be the same or different. When n1 is 2 or more, a plurality of R ０１ may be the same or different. When n2 is 2 or more, a plurality of R ０２ may be the same or different. When n3 is 2 or more, a plurality of R ０３ may be the same as or different from each other.

2. a resin component (A1) whose solubility in a developer changes under the action of an acid; and an acid generator component (B) that generates an acid upon exposure to light, The acid generator component (B) contains a compound represented by the following general formula (b0): The resist composition according to claim 1 . 【Chemistry 2】 [In the formula, M ｂ＋ is the cation (C0). － is the counter anion.

3. a resin component (A1) whose solubility in a developer changes under the action of an acid; and an acid diffusion controller component (D) that controls the diffusion of acid generated by exposure to light, The acid diffusion controller component (D) contains a compound represented by the following general formula (d0): The resist composition according to claim 1 . 【Transformation 3】 [In the formula, M ｄ＋ is the cation (C0). － is the counter anion.

4. It contains a resin component (A0) having a structural unit (a0) represented by the following general formula (a0-1): The resist composition according to claim 1 . 【Chemistry 4】 [wherein 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. M ａ＋ is the cation (C0). ０－ is a group containing an anion.

5. a resin component (A1) whose solubility in a developer changes under the action of an acid, the resin component (A1) has the structural unit (a0); The resist composition according to claim 4.

6. A method for forming a resist pattern, comprising: a step of forming a resist film on a support using the resist composition according to any one of claims 1 to 4; a step of exposing the resist film; and a step of developing the exposed resist film to form a resist pattern.

7. A compound represented by the following general formula (M0), which is used in the production of the resist composition according to claim 1: 【Transformation 5】 [In the formula, X ０１ and X 02 are each independently an acyl group, a mesyl group, a fluorine atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, or a thiocarbonyl group, and are different from each other. ０１ is an electron donating group. ０２ and R ０３ are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X ０１ may be the same or different. When nx2 is 2 or more, a plurality of X ０２ may be the same or different. When n1 is 2 or more, a plurality of R ０１ may be the same or different. When n2 is 2 or more, a plurality of R ０２ may be the same or different. When n3 is 2 or more, a plurality of R ０３ may be the same or different. － is the counter anion.

8. An acid generator comprising a compound represented by the following general formula (B0): 【Transformation 6】 [In the formula, X ０１ and X 02 are each independently an acyl group, a mesyl group, a fluorine atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, or a thiocarbonyl group, and are different from each other. ０１ is an electron donating group. ０２ and R ０３ are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X ０１ may be the same or different. When nx2 is 2 or more, a plurality of X ０２ may be the same or different. When n1 is 2 or more, a plurality of R ０１ may be the same or different. When n2 is 2 or more, a plurality of R ０２ may be the same or different. When n3 is 2 or more, a plurality of R ０３ may be the same or different. － is the counter anion.

9. An acid diffusion controller comprising a compound represented by the following general formula (D0): 【Transformation 7】 [In the formula, X ０１ and X 02 are each independently an acyl group, a mesyl group, a fluorine atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, or a thiocarbonyl group, and are different from each other. ０１ is an electron donating group. ０２ and R ０３ are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X ０１ may be the same or different. When nx2 is 2 or more, a plurality of X ０２ may be the same or different. When n1 is 2 or more, a plurality of R ０１ may be the same or different. When n2 is 2 or more, a plurality of R ０２ may be the same or different. When n3 is 2 or more, a plurality of R ０３ may be the same or different. － is the counter anion.

10. A polymeric compound having a structural unit (a0) represented by the following general formula (A0-1), which is used in the production of the resist composition according to claim 1: 【Transformation 8】 [In the formula, R is a hydrogen atom, a carbon atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. ０ is a group containing an anion. ０１ and X 02 are each independently an acyl group, a mesyl group, a fluorine atom, a halogenated alkyl group, a halogenated alkoxy group, a halogenated alkylamino group, a halogenated alkylthio group, a cyano group, a nitro group, a dialkylphosphono group, an alkylsulfonyl group, a sulfonyloxy group, an acylthio group, a sulfamoyl group, a thiocyanate group, or a thiocarbonyl group, and are different from each other. ０１ is an electron donating group. ０２ and R ０３ are each independently a substituent. nx1 and nx2 are each independently an integer of 1 to 4, n1 is an integer of 0 to 3, and nx1+nx2+n1≦5. n2 and n3 are each independently an integer of 0 to 4. When nx1 is 2 or more, a plurality of X ０１ may be the same or different. When nx2 is 2 or more, a plurality of X ０２ may be the same or different. When n1 is 2 or more, a plurality of R ０１ may be the same or different. When n2 is 2 or more, a plurality of R ０２ may be the same or different. When n3 is 2 or more, a plurality of R ０３ may be the same as or different from each other.

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