Resist composition and method for forming resist pattern

Abstract

The present invention provides: a resist composition capable of achieving high sensitivity, reducing roughness, and reducing the incidence of defects in resist pattern formation; and a resist pattern formation method in which the resist composition is used. The present invention relates to a resist composition that generates an acid upon exposure to light and exhibits changed solubility in a developing solution under the action of an acid. The resist composition contains a base component (A) that exhibits changed solubility in a developing solution under the action of an acid, an acid generator component (B) that generates an acid upon exposure to light, and an acid diffusion control component (D). The acid diffusion control component (D) contains a compound (D1) represented by general formula (d0-1) described in the description.

Description

Resist composition and method for forming a resist pattern

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

[0002] In lithography technology, for example, a resist film made of a resist material is formed on a substrate, the resist film is selectively exposed to light, and a developing process is performed to form a resist pattern of a predetermined shape on the resist film. A resist material in which the exposed area of ​​the resist film changes its properties to dissolve in the developing solution is called a positive type, and a resist material in which the exposed area changes its properties to not dissolve in the developing solution is called a negative type.

[0003] In recent years, advances in lithography technology have led to rapid miniaturization of patterns in the manufacturing of semiconductor devices and liquid crystal display elements. Generally, miniaturization is achieved by shortening the wavelength (increasing the energy) of the exposure light source. Specifically, while ultraviolet light, such as the g-line and i-line, was traditionally used for miniaturization, mass production of semiconductor devices using KrF excimer lasers and ArF excimer lasers has now begun. Furthermore, research is being conducted on even shorter wavelengths (higher energy) than these excimer lasers, such as EUV (extreme ultraviolet), EB (electron beam), and X-rays. In this context, resist materials require lithographic characteristics such as sensitivity to these exposure light sources or energy sources, and resolution capable of reproducing patterns of fine dimensions.

[0004] Conventionally, chemically amplified resist compositions have been used as resist materials that satisfy these requirements, and these compositions contain an acid generator component that generates acid upon exposure, and a substrate component whose solubility in the developer solution changes due to the action of the acid.

[0005] Furthermore, the base resin used in chemically amplified resist compositions generally has multiple constituent units to improve lithography characteristics and the like. For example, Patent Document 1 investigates a resist composition and a resist pattern formation method that can form a resist pattern with a good shape. Patent Document 1 describes a resist composition containing a base component (A) whose solubility in an alkaline developer changes due to the action of an acid, an acid generating agent component (B) that generates acid upon exposure, and a nitrogen-containing organic compound (D1) having a specific structure and a molecular weight of 200 or more.

[0006] Japanese Patent Application Publication No. 2009-109963

[0007] As lithography technology continues to advance and resist patterns become increasingly miniaturized, resist compositions are required to possess excellent lithographic properties that achieve high sensitivity to exposure light sources, reduced roughness, and reduced defect generation during development.

[0008] However, these lithography properties are in a trade-off relationship, and it is difficult to satisfy all of them. In conventional resist compositions such as the one described in Patent Document 1 above, there was still room for improvement in order to satisfy all of these properties at a high level.

[0009] The present invention has been made in view of the above circumstances, and aims to provide a resist composition that can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects in resist pattern formation, and a resist pattern formation method using the resist composition.

[0010] As a result of diligent research to solve the above problems, the present inventors have found that a resist composition and a resist pattern formation method using the resist composition can be obtained with the following configuration, which enables high sensitivity, reduction of roughness, and reduction of defect occurrence in resist pattern formation, and have completed the present invention.

[0011] In other words, the present invention is as follows. The resist composition according to the embodiment of the present invention is a resist composition that generates acid upon exposure and whose solubility in a developer changes due to the action of the acid, comprising a base component (A) whose solubility in a developer changes due to the action of the acid, an acid generating agent component (B) that generates acid upon exposure, and an acid diffusion control component (D), wherein the acid diffusion control component (D) comprises a compound (D1) represented by the following general formula (d0-1).

[0012]

[0013] [In general formula (d0-1), R １ R represents an organic group that does not have a hydrogen atom or a nitrogen atom. ２ R represents a hydrogen atom or a hydrocarbon group. ３ [where n1 represents a substituent, and n1 represents an integer between 0 and 5.]

[0014] Another embodiment of the present invention relates to a resist pattern formation method which includes the steps of forming a resist film on a support using the resist composition described in claim 1 or 2, exposing the resist film, and developing the resist film to form a resist pattern.

[0015] The present invention provides a resist composition that can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects in resist pattern formation, as well as a resist pattern formation method using the resist composition.

[0016] The embodiments for carrying out the present invention will be described in detail below. However, the present invention is not limited to the embodiments described below.

[0017] In this disclosure, "aliphatic" is defined as a concept relative to aromatic, meaning groups, compounds, etc., that do not possess aromaticity. Unless otherwise specified, "alkyl group" includes linear, branched, and cyclic monovalent saturated hydrocarbon groups. The same applies to alkyl groups in alkoxy groups. Unless otherwise specified, "alkylene group" includes linear, branched, and cyclic divalent saturated hydrocarbon groups. "Halogenated alkyl group" is a group in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms, and examples of such halogen atoms include fluorine, chlorine, bromine, and iodine atoms. "Fluorinated alkyl group" or "fluorinated alkylene group" means a group in which some or all of the hydrogen atoms of the alkyl group or alkylene group are substituted with fluorine atoms.

[0018] "Constituent unit" refers to the monomer unit (monomer unit) that makes up a polymer compound (resin, polymer, copolymer). When it is written as "may have substituents" or "may have substituents," it refers to the substitution of a hydrogen atom (-H) with a monovalent group, or a methylene group (-CH ２ This includes both cases where the negative (-) is substituted with a divalent group. "Exposure" is a concept that includes all forms of radiation irradiation.

[0019] "Constituent units derived from acrylic acid esters" refers to constituent units formed when the ethylenic double bond of an acrylic acid ester is cleaved. "Acrylic acid esters" are derived from acrylic acid (CH4). ２ This is a compound in which the hydrogen atom at the carboxyl group terminus of (=CH-COOH) is replaced by an organic group. In acrylic acid esters, the hydrogen atom bonded to the carbon atom at the α position may be replaced by a substituent. Substituents that replace the hydrogen atom bonded to the carbon atom at the α position (R α ) is an atom or group other than a hydrogen atom, such as an alkyl group having 1 to 5 carbon atoms, or an alkyl halogenated group having 1 to 5 carbon atoms. Also, acrylic acid esters have substituents (R α Itaconic acid diesters in which the substituent (R) is substituted with substituents containing an ester bond, or substituents (R αThis also includes α-hydroxyacrylic esters in which the α-hydroxyalkyl group is substituted with a hydroxyalkyl group or a group that modifies the hydroxyl group thereof. Unless otherwise specified, the α-carbon atom of the acrylic ester refers to the carbon atom to which the carbonyl group of the acrylic ester is bonded. Hereinafter, an acrylic ester in which the hydrogen atom bonded to the α-carbon atom is substituted with a substituent may be called an α-substituted acrylic ester. Furthermore, acrylic esters and α-substituted acrylic esters may be collectively referred to as "(α-substituted) acrylic esters".

[0020] The alkyl group as the α-substituent is preferably a linear or branched alkyl group, specifically an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc.). Furthermore, the halogenated alkyl group as the α-substituent is specifically a group in which some or all of the hydrogen atoms of the alkyl group as the α-substituent are replaced with halogen atoms. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc., with fluorine atoms being particularly preferred. Furthermore, the hydroxyalkyl group as the α-substituent is specifically a group in which some or all of the hydrogen atoms of the alkyl group as the α-substituent are replaced with hydroxyl groups. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, with 1 being the most preferred.

[0021] In this disclosure, a numerical range expressed using "~" means a range that includes the numbers before and after "~" as the lower and upper limits, respectively. Furthermore, in this disclosure, the amount of each component in a composition means the total amount of multiple substances corresponding to each component present in the composition, unless otherwise specified.

[0022] In addition, the chemical structural formulas in the present disclosure may be described as simplified structural formulas with hydrogen atoms omitted. In the present disclosure, depending on the structure represented by the chemical formula, an asymmetric carbon may exist, and some structures may have enantiomers or diastereomers. In such cases, these isomers are represented collectively by a single chemical formula. These isomers may be used alone or as a mixture. In the present disclosure, "mass%" and "weight%" are synonymous, and "parts by mass" and "parts by weight" are synonymous.

[0023] [Resist composition] A resist composition according to an embodiment of the present invention is a resist composition that generates an acid upon exposure and exhibits a change in solubility in a developer by the action of the acid, and comprises a base component (A) that exhibits a change in solubility in a developer by the action of the acid, an acid generator component (B) that generates an acid upon exposure, and an acid diffusion control component (D), wherein the acid diffusion control component (D) comprises a compound (D1) represented by the following general formula (d0-1).

[0024]

[0025] [In general formula (d0-1), R １ represents a hydrogen atom or an organic group having no nitrogen atom, R ２ represents a hydrogen atom or a hydrocarbon group, R ３ represents a substituent, and n1 represents an integer of 0 to 5.]]

[0026] When a resist film is formed using the resist composition of the present embodiment and selective exposure is performed on the resist film, an acid is generated in the exposed area of the resist film, and the action of the acid causes a change in the solubility of component (A) in the developer, while in the unexposed area of the resist film, the solubility of component (A) in the developer does not change. This results in a difference in solubility in the developer between the exposed area and the unexposed area of the resist film. Therefore, when the resist film is developed, if the resist composition is a positive type, the exposed area of the resist film is dissolved and removed to form a positive resist pattern, and if the resist composition is a negative type, the unexposed area of the resist film is dissolved and removed to form a negative resist pattern.

[0027] In this disclosure, a resist composition in which the exposed portion of the resist film is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern is referred to as a negative resist composition.

[0028] The resist composition of this embodiment may be a positive-type resist composition or a negative-type resist composition.

[0029] Furthermore, the resist composition of this embodiment may be for an alkaline development process that uses an alkaline developer for the development treatment during resist pattern formation, or it may be for a solvent development process that uses a developer containing an organic solvent (organic developer) for the development treatment.

[0030] In other words, the resist composition of this embodiment may be a "positive-type resist composition for alkaline development processes" that forms a positive-type resist pattern in an alkaline development process, or it may be a "negative-type resist composition for solvent development processes" that forms a negative-type resist pattern in a solvent development process.

[0031] The resist composition of this embodiment is a resist composition that generates acid upon exposure and whose solubility in a developer solution changes due to the action of the acid, and contains a base component (A) whose solubility in a developer solution changes due to the action of the acid, an acid generating agent component (B) that generates acid upon exposure, and an acid diffusion control component (D).

[0032] The resist composition of this embodiment includes a base component (A) whose solubility in the developer changes due to the action of an acid. Component (A) may generate acid upon exposure, in which case component (A) becomes a "base component that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid." When component (A) is a base component that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid, it is preferable that component (A1), described later, is a polymer compound that generates acid upon exposure and whose solubility in the developer changes due to the action of the acid. As such a polymer compound, a copolymer having a constituent unit that generates acid upon exposure can be used. Examples of constituent units that generate acid upon exposure include those that are known.

[0033] The resist composition of this embodiment includes an acid generator component (B) that generates acid upon exposure. Component (B) is not particularly limited, and any acid generator conventionally known for chemically amplified resist compositions can be used.

[0034] Furthermore, the resist composition of this embodiment contains an acid diffusion control component (D), the acid diffusion control component (D) contains a compound (D1) represented by the general formula (d0-1). The nucleophilicity of the nitrogen atom in compound (D1) is appropriately adjusted by the anilide structure. Therefore, compound (D1) acts as an acid diffusion control agent (quencher) that traps the acid generated by exposure in the resist composition, without hindering the efficient generation of acid. Thus, when used in a resist composition, high sensitivity and reduced roughness in resist pattern formation are achieved. Moreover, because the nucleophilicity of the nitrogen atom is appropriately adjusted, it can be used in combination with other components that would easily decompose with conventional acid diffusion control agents. Therefore, even when combined with other components that would cause defects with conventional acid diffusion control agents, it is possible to reduce defects in resist pattern formation. From the above, it is presumed that the resist composition of this embodiment can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects in resist pattern formation.

[0035] (A) Ingredients

[0036] In the resist composition of this embodiment, component (A) is a substrate component whose solubility in the developer changes due to the action of an acid. Component (A) may have increased solubility in the developer due to the action of an acid, or it may have decreased solubility in the developer due to the action of an acid. By using component (A), the polarity of the substrate component changes before and after exposure, so that good development contrast can be obtained not only in the alkaline development process but also in the solvent development process.

[0037] When an alkaline development process is applied, component (A) is poorly soluble in the alkaline developer before exposure. When acid is generated from component (B) upon exposure, the polarity of the substrate component (A) increases due to the action of the acid, and its solubility in the alkaline developer increases. Therefore, when a resist film obtained by coating the resist composition onto a support is selectively exposed during the formation of a resist pattern, the exposed parts of the resist film change from poorly soluble to soluble in the alkaline developer, while the unexposed parts of the resist film remain poorly soluble in the alkali. Thus, a positive-type resist pattern is formed by alkaline development.

[0038] On the other hand, when a solvent development process is applied, component (A) is highly soluble in organic developer before exposure. When acid is generated from component (B) upon exposure, the polarity of the substrate component (A) increases due to the action of the acid, and its solubility in organic developer decreases. Therefore, when selectively exposing a resist film obtained by coating the resist composition onto a support during the formation of a resist pattern, the exposed parts of the resist film change from soluble to poorly soluble in organic developer, while the unexposed parts of the resist film remain soluble. Thus, by developing with an organic developer, a contrast can be created between the exposed and unexposed parts, forming a negative-type resist pattern.

[0039] In the resist composition of this embodiment, component (A) may be used alone or in combination of two or more types.

[0040] (A) Component is a lactone-containing cyclic group, -SO ２- The polymer compound (A1) may include a structural unit containing either a cyclic group containing a carbonate or a cyclic group containing a carbonate.

[0041] Regarding component (A1), in the resist composition according to the embodiment of the present invention, component (A) is a lactone-containing cyclic group, -SO ２ - The polymer compound (A1) may include a constituent unit (a1) containing a cyclic group or a carbonate-containing cyclic group.

[0042] (Constituent unit (a1)) Lactone-containing cyclic group of constituent unit (a1), -SO ２ - The cyclic group containing or carbonate-containing cyclic group is effective in improving the adhesion of the resist film to the substrate when component (A1) is used to form the resist film. Furthermore, having the constituent unit (a1) improves lithography characteristics, etc., by having effects such as appropriately adjusting the acid diffusion length, improving the adhesion of the resist film to the substrate, and appropriately adjusting the solubility during development.

[0043] A "lactone-containing cyclic group" refers to a cyclic group that contains a ring (lactone ring) containing -O-C(=O)- within its cyclic skeleton. The lactone ring is counted as the first ring. If it consists only of a lactone ring, it is called a monocyclic group. If it also has other ring structures, it is called a polycyclic group regardless of those structures. A lactone-containing cyclic group may be a monocyclic group or a polycyclic group.

[0044] The lactone-containing cyclic group in the constituent unit (a1) is not particularly limited and any group can be used. Specifically, examples of lactone-containing cyclic groups include the groups represented by the following general formulas (a1-1-1) to (a1-1-7).

[0045]

[0046] [In the formula, Ra' ２１ Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ２- A cyclic group containing an oxygen atom (-O-) or a sulfur atom (-S-) is an alkylene group having 1 to 5 carbon atoms, an oxygen atom, or a sulfur atom, n' is an integer from 0 to 2, and m' is 0 or 1. * represents a bond.

[0047] In the above general formulas (a1-1-1) to (a1-1-7), Ra' ２１ The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, examples of alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, etc. Among these, the methyl group or ethyl group is preferred, and the methyl group is particularly preferred.

[0048] Ra' ２１ The alkoxy group in is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, the alkoxy group is the Ra' ２１ Examples of alkyl groups in this context include groups formed by linking an alkyl group with an oxygen atom (-O-).

[0049] Ra' ２１ Examples of halogen atoms in this compound include fluorine, chlorine, bromine, and iodine atoms, with fluorine being preferred. ２１ The halogenated alkyl group in is the Ra' ２１ Examples include groups in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms. Fluorinated alkyl groups are preferred as the halogenated alkyl group, and perfluoroalkyl groups are particularly preferred. Ra' ２１ In -COOR'' and -OC(=O)R'', R'' is either a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ２ - It contains a cyclic group.

[0050] The alkyl group in R'' may be linear, branched, or cyclic, and preferably has 1 to 15 carbon atoms. If R'' is a linear or branched alkyl group, it is preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. If R'' is a cyclic alkyl group, it is preferably 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, examples of cyclic alkyl groups include groups obtained by removing one or more hydrogen atoms from monocycloalkanes, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specifically, examples of cyclic alkyl groups include groups obtained by removing one or more hydrogen atoms from monocycloalkanes such as cyclopentane and cyclohexane; and adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Examples include groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as decane and tetracyclododecane.

[0051] Examples of lactone-containing cyclic groups in R'' include those similar to the groups represented by the general formulas (a1-1-1) to (a1-1-7) above. Examples of carbonate-containing cyclic groups in R'' include those similar to the carbonate-containing cyclic groups described later, specifically the groups represented by the general formulas (a1-3-1) to (a1-3-3) above. Examples of -SO in R'' ２ - The cyclic group containing it is -SO, which will be described later. ２ - Similar to the contained cyclic groups, specifically the groups represented by general formulas (a1-2-1) to (a1-2-4), respectively. Ra' ２１ The hydroxyalkyl group in is preferably one with 1 to 6 carbon atoms, specifically the Ra' ２１ Examples include groups in which at least one hydrogen atom of the alkyl group is substituted with a hydroxyl group.

[0052] In the general formulas (a1-1-2), (a1-1-3), and (a1-1-5) above, the alkylene group having 1 to 5 carbon atoms in A'' is preferably a linear or branched alkylene group, such as a methylene group, ethylene group, n-propylene group, isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, a specific example is a group in which -O- or -S- is interposed at the end or between carbon atoms of the alkylene group, such as -O-CH ２ -ien-CH ２ -O-CH ２ -, -S-CH ２ -ien-CH ２ -S-CH ２ Examples include the following. A'' is preferably an alkylene group or -O- having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0053] The following are specific examples of the groups represented by the general formulas (a1-1-1) to (a1-1-7), as well as other lactone-containing cyclic groups. * indicates a bond.

[0054]

[0055]

[0056] "-SO ２ - A "cyclic group containing -SO" refers to a group whose ring skeleton contains -SO ２ This indicates a cyclic group containing a ring with -, specifically -SO ２ - is a cyclic group in which the sulfur atom (S) forms part of the cyclic skeleton. ２ The ring containing the - group is counted as the first ring. If only this ring exists, it is called a monocyclic group. If it also has other ring structures, it is called a polycyclic group regardless of those structures. -SO ２ - The contained cyclic group may be a monocyclic group or a polycyclic group. - SO ２ - The contained cyclic group, in particular, has -O-SO in its cyclic skeleton. ２ A cyclic group containing -, i.e., -O-SO ２ Preferably, the -O-S- in the - group is a cyclic group containing a sultone ring that forms part of the cyclic skeleton.

[0057] -SO ２ - More specifically, the cyclic groups included are those represented by the following general formulas (a1-2-1) to (a1-2-4).

[0058]

[0059] [In the formula, Ra' ５１ Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ２ - It is a cyclic group containing; 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 from 0 to 2. * represents a bond.

[0060] In the general formulas (a1-2-1) to (a1-2-2) above, A'' is the same as A'' in the general formulas (a1-1-2), (a1-1-3), and (a1-1-5). Ra' ５１ In this context, the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR'', -OC(=O)R'', and hydroxyalkyl group are, respectively, Ra' in the general formulas (a1-1-1) to (a1-1-7). ２１ The same things mentioned in the explanation about this topic can be cited.

[0061] Specific examples of the groups represented by the general formulas (a1-2-1) to (a1-2-4) are given below. In the formulas, "Ac" indicates an acetyl group. * indicates a bond.

[0062]

[0063]

[0064]

[0065] A "carbonate-containing cyclic group" refers to a cyclic group that contains a ring (carbonate ring) containing -O-C(=O)-O- within its cyclic framework. The carbonate ring is counted as the first ring. If it consists only of a carbonate ring, it is called a monocyclic group. If it also has other ring structures, it is called a polycyclic group regardless of those structures. A carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.

[0066] Any carbonate ring-containing cyclic group can be used without any particular limitations. Specifically, examples of carbonate ring-containing cyclic groups include the groups represented by the following general formulas (a1-3-1) to (a1-3-3).

[0067]

[0068] [In the formula, Ra' ｘ３１ Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC(=O)R'', a hydroxyalkyl group, or a cyano group; R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ２ - It is a cyclic group containing an oxygen atom or a sulfur atom; A'' is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom; p' is an integer from 0 to 3; and q' is 0 or 1. * represents a bond.

[0069] In the general formulas (a1-3-2) to (a1-3-3) above, A'' is the same as A'' in the general formulas (a1-1-2), (a1-1-3), and (a1-1-5). Ra' ３１ In this context, the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR'', -OC(=O)R'', and hydroxyalkyl group are, respectively, Ra' in the general formulas (a1-1-1) to (a1-1-7). ２１ The same things mentioned in the explanation about this topic can be cited.

[0070] Specific examples of the groups represented by the general formulas (a1-3-1) to (a1-3-3) are given below. * indicates a bond.

[0071]

[0072] Among the constituent units (a1), those derived from acrylic acid esters in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent are preferred.

[0073] The constituent unit (a1) is preferably a constituent unit represented by the following general formula (a1-1).

[0074]

[0075] [In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogen having 1 to 5 carbon atoms. Ya ２１ It is a single bond or a divalent linking group. La ２１ The elements are -O-, -COO-, -CON(R')-, -OCO-, -CONHCO-, or -CONHCS-, where R' represents a hydrogen atom or a methyl group. However, La ２１ If -O-, Ya ２１ It does not become -CO-. Ra ２１ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ２ - It contains a cyclic group.

[0076] In the above formula (a1-1), R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and a hydrogen atom or a methyl group is particularly preferred due to their industrial availability.

[0077] In the above formula (a1-1), Ya ２１ The divalent linking group in is not particularly limited, but preferably includes divalent hydrocarbon groups which may have substituents, and divalent linking groups which contain heteroatoms. Among the above, Ya ２１ Preferably, the group is a single bond, an ester bond [-C(=O)-O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0078] Ra ２１ Lactone-containing cyclic groups in -SO ２- Suitable examples of carbonate-containing cyclic groups include the groups represented by the general formulas (a1-1-1) to (a1-1-7), the groups represented by the general formulas (a1-2-1) to (a1-2-4), and the groups represented by the general formulas (a1-3-1) to (a1-3-3), respectively. Among these, lactone-containing cyclic groups or -SO ２ - A cyclic group containing -SO is preferred, and the groups represented by the general formulas (a1-1-1), (a1-1-2), (a1-1-6), or (a1-2-1) are more preferred. Lactone-containing cyclic group, -SO ２ Specifically, as the carbonate-containing cyclic group, 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 more preferred.

[0079] The constituent unit (a1) of component (A1) may be one type or two or more types. When component (A1) has constituent unit (a1), the proportion of constituent unit (a1) is preferably 5 to 60 mol%, more preferably 10 to 60 mol%, even more preferably 20 to 55 mol%, and particularly preferably 30 to 50 mol%, based on the total amount (100 mol%) of all constituent units that make up component (A1). If the proportion of constituent unit (a1) is above the preferred lower limit, the effects of including constituent unit (a1) are sufficiently obtained due to the effects described above, and if it is below the preferred upper limit, a balance with other constituent units can be achieved, resulting in good lithography characteristics in various fields.

[0080] (Constituent unit (a2)) Component (A1) may also have constituent unit (a2) containing a polar group-containing aliphatic hydrocarbon group in addition to constituent unit (a1) (excluding those corresponding to constituent unit (a1)). The presence of constituent unit (a2) in component (A1) increases the hydrophilicity of component (A), contributing to improved lithography properties. Furthermore, the acid diffusion length can be appropriately adjusted.

[0081] Examples of polar groups include hydroxyl groups, cyano groups, carboxyl groups, and hydroxyalkyl groups in which some of the hydrogen atoms of the alkyl group are replaced with fluorine atoms, with hydroxyl groups being particularly preferred. Examples of aliphatic hydrocarbon groups include linear or branched hydrocarbon groups having 1 to 10 carbon atoms (preferably alkylene groups) and cyclic aliphatic hydrocarbon groups (cyclic groups). The cyclic group may be monocyclic or polycyclic, and can be appropriately selected from among the many proposed cyclic groups, for example, in resins for ArF excimer laser resist compositions.

[0082] When the cyclic group is a monocyclic group, it is more preferable that the number of carbon atoms be 3 to 10. Among these, structural units derived from acrylic acid esters containing an aliphatic monocyclic group containing a hydroxyl group, a cyano group, a carboxyl group, or a hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms are more preferred. Examples of such monocyclic groups include groups obtained by removing two or more hydrogen atoms from a monocycloalkane. Specifically, examples of such monocyclic groups include groups obtained by removing two or more hydrogen atoms from monocycloalkanes such as cyclopentane, cyclohexane, and cyclooctane. Among these monocyclic groups, groups obtained by removing two or more hydrogen atoms from cyclopentane and groups obtained by removing two or more hydrogen atoms from cyclohexane are industrially preferred.

[0083] When the cyclic group is a polycyclic group, it is more preferable that the number of carbon atoms in the polycyclic group be 7 to 30. Among these, structural units derived from acrylic acid esters containing an aliphatic polycyclic group containing a hydroxyl group, a cyano group, a carboxyl group, or a hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms are more preferable. Examples of the polycyclic group include groups obtained by removing two or more hydrogen atoms from bicycloalkanes, tricycloalkanes, tetracycloalkanes, etc. Specifically, examples of the polycyclic group include adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６Examples include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as decane and tetracyclododecane. Among these polycyclic groups, groups obtained by removing two or more hydrogen atoms from adamantane, norbornane, and tetracyclododecane are industrially preferred.

[0084] The constituent unit (a2) is not particularly limited and any unit can be used as long as it contains a polar group-containing aliphatic hydrocarbon group. Preferably, the constituent unit (a2) is a constituent unit derived from an acrylic acid ester in which the hydrogen atom bonded to the α-carbon atom may be substituted with a substituent, and which contains a polar group-containing aliphatic hydrocarbon group.

[0085] As for the constituent unit (a2), 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, a constituent unit derived from hydroxyethyl ester of acrylic acid is preferred.

[0086] Furthermore, as for the constituent unit (a2), when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a polycyclic group, the constituent unit represented by formula (a2-1), formula (a2-2), and formula (a2-3) below are preferred; when it is a monocyclic group, the constituent unit represented by formula (a2-4) is preferred.

[0087]

[0088] [In the formula, R is the same as above, j is an integer from 1 to 3, k is an integer from 1 to 3, t' is an integer from 1 to 3, l is an integer from 0 to 5, and s is an integer from 1 to 3.]

[0089] In formula (a2-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3rd position of the adamantyl group. It is preferable that j is 1, and it is particularly preferable that the hydroxyl group is bonded to the 3rd position of the adamantyl group.

[0090] In formula (a2-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.

[0091] In formula (a2-3), t' is preferably 1. l is preferably 1. s is preferably 1. In these cases, 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 5th or 6th position of the norbornyl group.

[0092] In formula (a2-4), 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.

[0093] The constituent units (a2) of component (A1) may be one type or two or more types. When component (A1) has constituent units (a2), the proportion of constituent units (a2) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and even more preferably 5 to 20 mol%, relative to the total amount (100 mol%) of all constituent units that make up component (A1).

[0094] By setting the proportion of constituent unit (a2) above a preferred lower limit, the effects of including constituent unit (a2) are fully obtained through the aforementioned effects. If it is below a preferred upper limit, a balance with other constituent units can be maintained, resulting in good lithography characteristics.

[0095] (Constituent unit (a3)) The polymer compound (A1) may further have a constituent unit (a3) ​​represented by the following general formula (a-3).

[0096]

[0097] [In general formula (a-3), R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halogen having 1 to 5 carbon atoms. Va ３ n represents a divalent hydrocarbon group which may have an ether bond. ａ３ This represents an integer between 0 and 2.３ This represents an acid-dissociable group having an alicyclic hydrocarbon group.

[0098] R in equation (a-3) is the same as R in equation (a-1) above. Va in equation (a-3) ３ The divalent hydrocarbon group represented by may have an ether bond, which is preferably an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

[0099] The constituent unit (a3) ​​is an acid-degradable group whose polarity increases upon the action of an acid, and is a constituent unit that includes an acid-degradable group having an alicyclic hydrocarbon group (excluding those corresponding to constituent units (a1) and (a2)).

[0100] An "acid-degradable group" is a group that is acid-degradable, meaning that at least some of the bonds in its structure can be cleaved by the action of an acid. Examples of acid-degradable groups whose polarity increases by the action of an acid include groups that decompose by the action of an acid to produce polar groups. Examples of polar groups include carboxyl groups, hydroxyl groups, amino groups, and sulfo groups (-SO4). ３ Examples include H). Among these, polar groups containing -OH in their structure (hereinafter sometimes referred to as "OH-containing polar groups") are preferred, carboxyl groups or hydroxyl groups are more preferred, and carboxyl groups are particularly preferred.

[0101] More specifically, examples of acid-degradable groups include groups in which the aforementioned polar group is protected by an acid-dissociable group (for example, a group in which the hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group). Here, "acid-dissociable group" refers to both (i) a group having acid-dissociability in which the bond between the acid-dissociable group and an atom adjacent to it can be cleaved by the action of an acid, or (ii) a group in which, after some of the bonds are cleaved by the action of an acid, a decarboxylation reaction occurs, further causing the bond between the acid-dissociable group and an atom adjacent to it to be cleaved.

[0102] The acid-dissociable group constituting the acid-degradable group must be less polar than the polar group generated by its dissociation. This ensures that when the acid-dissociable group dissociates due to the action of acid, a polar group with higher polarity is generated, increasing the polarity. As a result, the overall polarity of component (A1) increases. This increase in polarity relatively alters the solubility in the developer; solubility increases when the developer is an alkaline developer, and decreases when the developer is an organic developer.

[0103] The constituent unit (a3) ​​contains an acid-degradable group having an alicyclic hydrocarbon group, preferably an acid-degradable group having a monocyclic alicyclic hydrocarbon group, and more preferably an acid-dissociable group having a monocyclic alicyclic hydrocarbon group. The acid-degradable group (acid-dissociable group) in the constituent unit (a3) ​​has an appropriate bulkiness, which allows for appropriate control of acid diffusion and solubility of the developer, thereby reducing roughness when forming the resist pattern. Examples of acid-dissociable groups in the constituent unit (a3) ​​include those previously proposed as acid-dissociable groups for base resins used in chemically amplified resists. Specifically, examples of acid-dissociable groups proposed for base resins used in chemically amplified resists include the "acetal-type acid-dissociable group" and the "tertiary alkyl ester-type acid-dissociable group" described below.

[0104] - Acetal-type acid-dissociating group: Among the polar groups, an example of an acid-dissociating group that protects a carboxyl group or a hydroxyl group is the acid-dissociating group represented by the following formula (a3-r-1) (hereinafter sometimes referred to as an "acetal-type acid-dissociating group").

[0105]

[0106] [In formula (a3-r-1), Ra' ０１ , Ra' ０２ Each represents either a hydrogen atom or an alkyl group. Ra' ０３ Ra' is an alicyclic hydrocarbon group. ０３ Ra' ０１ , Ra' ０２ It may combine with any of the following to form a ring.

[0107] In formula (a3-r-1), Ra' ０１ and Ra' ０２ , it is preferable that at least one is a hydrogen atom, and more preferable that both are hydrogen atoms. Ra' ０１ or Ra' ０２ is an alkyl group, examples of the alkyl group include the same alkyl groups as those recited as substituents that may be bonded to the carbon atom at the α-position in the description of the above α-substituted acrylic acid ester, and an alkyl group having 1 to 5 carbon atoms is preferable. Specifically, linear or branched alkyl groups are preferably mentioned. More specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and the like. A methyl group or an ethyl group is more preferable, and a methyl group is particularly preferable.

[0108] In formula (a3-r-1), Ra' ０３ represents an alicyclic hydrocarbon group, which may be a polycyclic group or a monocyclic group, and is preferably a monocyclic group. As the alicyclic hydrocarbon group that is a monocyclic group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like.

[0109] As the alicyclic hydrocarbon group that is a polycyclic group, a group obtained by removing one hydrogen atom from a polycycloalkane is preferable. The polycycloalkane preferably has 7 to 12 carbon atoms, and specific examples thereof include adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ decane, tetracyclododecane, and the like. The alicyclic hydrocarbon group for Ra' ０３ may have a substituent. Examples of the substituent include -R Ｐ１ , -R Ｐ２ -O-R Ｐ１ , -R Ｐ２ -CO-R Ｐ１ , -R Ｐ２ -CO-O-R 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 ０５ ").

[0110] Here, R Ｐ１ is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Further, R Ｐ２ is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Provided that part or all of the hydrogen atoms in the chain saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group and aromatic hydrocarbon group of R Ｐ１ and R Ｐ２ may be substituted with fluorine atoms. The alicyclic hydrocarbon group may have one or more of one type of said substituents alone, or may have one or more of each of a plurality of types of said substituents.

[0111] 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, a nonyl 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, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, and a cyclododecyl group. Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

[0112] Ra' ０３ is Ra' ０１ , Ra' ０２When combined with any of the above to form a monocycle (a ring in which some of the carbon atoms of a monocyclic alicyclic hydrocarbon are replaced by oxygen atoms), the monocycle is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group of the monocycle include a tetrahydropyranyl group and a tetrahydrofuranyl group.

[0113] • Tertiary alkyl ester type acid-dissociating group: Among the polar groups, an example of an acid-dissociating group that protects the carboxyl group is the acid-dissociating group represented by the following formula (a3-r-2). Note that among the acid-dissociating groups represented by the following formula (a3-r-2), Ra' ０４ ~Ra' ０６ When each of these groups is an alkyl group, they are sometimes referred to as "tertiary alkyl ester type acid-dissociable groups" for convenience.

[0114]

[0115] [In formula (a3-r-2), Ra' ０４ ~Ra' ０６ Each of these is a hydrocarbon group, Ra' ０４ ~Ra' ０６ At least one of them is an alicyclic hydrocarbon group, or Ra' ０５ , Ra' ０６ These are bonded together to form an alicyclic hydrocarbon group.

[0116] Ra' ０４ ~Ra' ０６ Examples of hydrocarbon groups include linear or branched alkyl groups, linear or cyclic alkenyl groups, or cyclic hydrocarbon groups. However, Ra' ０４ ~Ra' ０６ At least one of them is an alicyclic hydrocarbon group, or Ra' ０５ , Ra' ０６ These molecules are bonded to each other to form an alicyclic hydrocarbon group.

[0117] The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specifically, examples of the linear alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. 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. The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, examples of the branched alkyl group 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.

[0118] Ra' ０４ ~Ra' ０６ If either of these is a cyclic hydrocarbon group, the hydrocarbon group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group is preferably a monocycloalkane from which one or more hydrogen atoms have been removed. The monocycloalkane is preferably one having 3 to 6 carbon atoms, specifically cyclopentane, cyclohexane, and the like.

[0119] Ra' ０４ ~Ra' ０６ If any of these becomes an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12.

[0120] Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which some of the carbon atoms constituting the aromatic hydrocarbon ring are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of aromatic heterocycles include pyridine rings and thiophene rings.

[0121] Specifically, examples of the aromatic hydrocarbon group include: a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group obtained by removing one hydrogen atom from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); and a group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc.). The number of carbon atoms in the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

[0122] The cyclic hydrocarbon group may have substituents. These substituents include Ra' in formula (a3-r-1). ０３ Examples include substituents similar to those that may be present on the alicyclic hydrocarbon group in Ra'. ０５ and Ra' ０６ When these groups bond to each other to form a ring, suitable examples of the acid-dissociable group include the group represented by the following formula (a3-r2-1), the group represented by the following formula (a3-r2-2), and the group represented by the following formula (a3-r2-3). On the other hand, Ra' ０４ ~Ra' ０６ When the groups are independent hydrocarbon groups that are not bonded to each other, a suitable example of the acid-dissociable group is the group represented by the following formula (a3-r2-4). In the following formula, * represents a bond.

[0123]

[0124] [In formula (a3-r2-1), Rax' １０ 'Rax' represents an alkyl group with 1 to 10 carbon atoms. １１ Rax' １０ This indicates a group that forms an alicyclic hydrocarbon group together with the bonded carbon atom.

[0125] In formula (a3-r2-2), Yax is a carbon atom. Xax is a group that forms an alicyclic hydrocarbon group together with Yax. Some or all of the hydrogen atoms in this alicyclic hydrocarbon group may be substituted. Rax ０１ ~Rax ０３ Each of these is independently a hydrogen atom, a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms in these linear saturated hydrocarbon groups and aliphatic cyclic saturated hydrocarbon groups may be substituted. Rax ０１ ~Rax ０３ Two or more of these may be bonded together to form a ring structure.

[0126] In formula (a3-r2-3), Yab is a carbon atom. Xab is a group that forms an alicyclic hydrocarbon group together with Yab. Rax ０４ This is an aromatic hydrocarbon group which may have substituents.

[0127] In formula (a3-r2-4), Rax' １２ and Rax' １３ Each of these is independently a monovalent, chain-like saturated hydrocarbon group having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Rax' １４ This is an alicyclic hydrocarbon group. * indicates a bond (the same applies below).

[0128] In the above formula (a3-r2-1), Rax' １０ The alkyl groups having 1 to 10 carbon atoms in this context include linear or branched alkyl groups.

[0129] The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specifically, the linear alkyl group may be a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and so on, with the methyl group or the ethyl group being preferred.

[0130] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples of the branched alkyl group include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc., with isopropyl group being preferred.

[0131] Rax' in the above formula (a3-r2-1) １０ Among the above, linear alkyl groups having 1 to 5 carbon atoms are preferred, and specifically, methyl groups and ethyl groups are preferred.

[0132] In the above formula (a3-r2-1), Rax' １１ (Rax' １０ The aliphatic cyclic group (which forms an alicyclic hydrocarbon with the bonded carbon atom) is preferably a monocyclic alicyclic hydrocarbon group, for example, a group obtained by removing two or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one having 3 to 10 carbon atoms, more preferably one having 3 to 8 carbon atoms, and even more preferably one having 3 to 6 carbon atoms. Specifically, cyclopentane and cyclohexane are suitable examples of the monocycloalkane.

[0133] In formula (a3-r2-2), the alicyclic hydrocarbon group that Xax forms together with Yax is preferably a monocyclic alicyclic hydrocarbon group, and in formula (a3-r2-1), Rax' １１ This is the same as what was explained earlier.

[0134] In formula (a3-r2-2), Rax ０１ ~Rax ０３Examples of monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups.

[0135] Rax ０１ ~Rax ０３ Examples of monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl groups. ０１ ~Rax ０３ Of the above, from the viewpoint of ease of synthesis of monomer compounds, hydrogen atoms and monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms are preferred, and among these, hydrogen atoms, methyl groups, and ethyl groups are more preferred, with hydrogen atoms being particularly preferred.

[0136] The aforementioned Rax ０１ ~Rax ０３ Examples of substituents on a chain-like saturated hydrocarbon group or an aliphatic cyclic saturated hydrocarbon group represented by the above Ra ０５ Similar groups can be cited. Rax ０１ ~Rax ０３ Groups containing a carbon-carbon double bond formed by two or more of these groups bonding to each other to form a cyclic structure include, for example, cyclopentenyl group, cyclohexenyl group, methylcyclopentenyl group, methylcyclohexenyl group, cyclopentylideneethenyl group, and cyclohexyllideneethenyl group. Among these, cyclopentenyl group, cyclohexenyl group, and cyclopentylideneethenyl group are preferred from the viewpoint of ease of synthesis of monomer compounds.

[0137] In formula (a3-r2-3), the alicyclic hydrocarbon group formed by Xab together with Yab is preferably a monocyclic alicyclic hydrocarbon group, and in formula (a3-r2-1), Rax' １１ This is the same as what was explained earlier.

[0138] In formula (a3-r2-3), Rax ０４In this context, aromatic hydrocarbon groups include groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Rax ０４ The group is preferably an aromatic hydrocarbon ring having 6 to 15 carbon atoms from which one or more hydrogen atoms have been removed; more preferably a group from which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene; even more preferably a group from which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene; particularly preferably a group from which one or more hydrogen atoms have been removed from benzene or naphthalene; and most preferably a group from which one or more hydrogen atoms have been removed from benzene.

[0139] Rax in equation (a3-r2-3) ０４ Examples of substituents that may be present include methyl groups, ethyl groups, propyl groups, hydroxyl groups, carboxyl groups, halogen atoms (fluorine atoms, chlorine atoms, bromine atoms, etc.), alkoxy groups (methoxy groups, ethoxy groups, propoxy groups, butoxy groups, etc.), alkyloxycarbonyl groups, and the like.

[0140] In formula (a3-r2-4), Rax' １２ and Rax' １３ These are, independently, monovalent, chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms. １２ and Rax' １３ In this, the monovalent chain-like saturated hydrocarbon group having 1 to 10 carbon atoms is the aforementioned Rax ０１ ~Rax ０３ Examples include monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms. Some or all of the hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted.

[0141] Rax' １２ and Rax' １３ Among these, alkyl groups having 1 to 5 carbon atoms are preferred, and methyl groups and ethyl groups are more preferred. １２ and Rax' １３ When a chain-like saturated hydrocarbon group represented by is substituted, the substituent may be, for example, the above-mentioned Ra ０５ Similar bases can be cited.

[0142] In formula (a3-r2-4), Rax' １４ It is preferably an alicyclic hydrocarbon group, and may be a monocyclic alicyclic hydrocarbon group having substituents. １４ Examples of alicyclic hydrocarbon groups include groups obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane is preferably one with 3 to 10 carbon atoms, more preferably one with 3 to 8 carbon atoms, and even more preferably one with 3 to 6 carbon atoms. Specifically, cyclopentane and cyclohexane are preferred examples of alicyclic hydrocarbon groups. Rax' １４ A substituent that may be present is Rax ０４ Examples of substituents that may be present include those similar to those that the molecule may have.

[0143] Specific examples of the group represented by the above formula (a3-r2-1) are given below. In the following formula, * represents a bond.

[0144]

[0145]

[0146] Specific examples of the group represented by the above formula (a3-r2-2) are given below. In the following formula, * represents a bond.

[0147]

[0148]

[0149]

[0150] Specific examples of the group represented by the above formula (a3-r2-3) are given below. In the following formula, * represents a bond.

[0151]

[0152] Specific examples of the group represented by the above formula (a3-r2-4) are given below. In the following formula, * represents a bond.

[0153]

[0154] ・Tertiary alkyloxycarbonylic acid dissociable group: Among the polar groups, an example of an acid-dissociable group that protects a hydroxyl group is the acid-dissociable group represented by the following formula (a3-r-3) (hereinafter referred to as the "tertiary alkyloxycarbonylic acid dissociable group" for convenience).

[0155]

[0156] [In the formula, Ra' ７ ~Ra' ９ Each of these represents an alkyl group.

[0157] In formula (a3-r-3), Ra' ７ ~Ra' ９ Each alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably 1 to 3 carbon atoms. Furthermore, the total number of carbon atoms in each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

[0158] As for the constituent unit (a3), among the above, Ra ３ Preferably, is an acid-dissociable group represented by the formula (a3-r-1) or (a3-r-3).

[0159] The following are specific examples of the constituent unit (a3) ​​represented by the general formula (a-3). In the formula below, R α This represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0160]

[0161]

[0162]

[0163]

[0164]

[0165]

[0166]

[0167]

[0168]

[0169] (A1) The constituent units (a3) ​​that the component may have may be one type or two or more types.

[0170] In component (A1), the proportion of constituent unit (a3) ​​is preferably 20 to 85 mol%, more preferably 30 to 80 mol%, and particularly preferably 35 to 70 mol%, relative to the total (100 mol%) of all constituent units that make up component (A1). By setting the proportion of constituent unit (a3) ​​to be above the preferred lower limit, lithography characteristics such as roughness reduction are improved. Furthermore, by setting the proportion of constituent unit (a3) ​​to be below the preferred upper limit, a balance with other constituent units can be achieved, resulting in good lithography characteristics in various aspects.

[0171] <<Other Constituent Units>> Component (A1) may have other constituent units other than the constituent units (a1), (a2), and (a3) ​​described above. Examples of other constituent units include a constituent unit (a5) containing a hydroxystyrene skeleton and a constituent unit (a6) containing an acid-nondissociable aliphatic cyclic group. Many of the constituent units (a4) to (a6) that have been conventionally known for use as resin components in resist compositions can be used. Component (A1) contained in the resist composition may be used alone or in combination of two or more types.

[0172] In the resist composition of the present embodiment, the resin component which is the component (A1) may include a polymer compound having the structural unit (a1), or a polymer compound having the structural unit (a1) and further having the structural unit (a2) and / or the structural unit (a3). One type of polymer may be used alone, or two or more types may be used in combination. Preferable examples of the component (A1) include a polymer compound composed of a repeating structure of the structural unit (a1) and the structural unit (a2), a polymer compound composed of a repeating structure of the structural unit (a1) and the structural unit (a3), a polymer compound composed of a repeating structure of the structural unit (a1), the structural unit (a2) and the structural unit (a3), and a polymer compound composed of a repeating structure of the structural unit (a1), the structural unit (a2), the structural unit (a3) and other structural units.

[0173] The component (A1) can be produced by dissolving monomers that derive each structural unit in a polymerization solvent, adding a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate (e.g., V-601) thereto, and then performing polymerization. Alternatively, the component (A1) can be produced by dissolving a monomer that derives the structural unit (a1), optionally a monomer that derives the structural unit (a2), optionally a monomer that derives the structural unit (a3), and optionally a monomer that derives other structural units besides these in a polymerization solvent, adding a radical polymerization initiator as described above thereto to perform polymerization, and then carrying out a deprotection reaction. In addition, during polymerization, for example, HS-CH ２ -CH ２ -CH ２ -C(CF ３ ) ２ -OH by using a chain transfer agent such as this in combination, -C(CF ３ ) ２ -OH group may be introduced at the terminal. As described above, a copolymer into which a hydroxyalkyl group in which part of hydrogen atoms of an alkyl group are substituted with fluorine atoms is introduced is effective for reducing development defects and reducing LER (line edge roughness: uneven irregularities on line side walls).

[0174] The weight-average molecular weight (Mw) of component (A1) (in terms of polystyrene equivalent, determined by gel permeation chromatography (GPC)) is not particularly limited, but is preferably from 1,000 to 100,000, and more preferably from 5,000 to 50,000. When the Mw of component (A1) is not more than the preferred upper limit of this range, component (A1) has sufficient solubility in a resist solvent for use as a resist; and when the Mw of component (A1) is not less than the preferred lower limit of this range, dry etching resistance and the cross-sectional shape of a resist pattern are favorable. The dispersity (Mw / Mn) of 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. Here, Mn represents the number-average molecular weight.

[0175] ・Regarding component (A2), the resist composition of the present embodiment may further contain, as component (A), a base material component (hereinafter referred to as "component (A2)") that does not fall under the above component (A1), and whose solubility in a developer changes due to the action of an acid.

[0176] Component (A2) is not particularly limited, and may be arbitrarily selected from a large number of conventionally known base material components for chemically amplified resist compositions. As component (A2), one type of high molecular compound or low molecular compound may be used alone, or two or more types may be used in combination.

[0177] The proportion of component (A1) in component (A), relative to the total mass of component (A), is preferably 25% by mass or more, more preferably 50% by mass or more, still more preferably 75% by mass or more, and may even be 100% by mass. When this proportion is 25% by mass or more, higher sensitivity can be achieved, and a resist pattern with reduced roughness and reduced occurrence of defects is easily formed. In the resist composition of the present embodiment, the content of component (A) may be adjusted according to the intended thickness of the resist film to be formed, and other factors.

[0178] ≪Component (B)≫ In addition to the above-described component (A) and component (D) described below, the resist composition according to the embodiment of the present invention further contains an acid generating agent component (B) (hereinafter referred to as "component (B)") that generates acid upon exposure. Component (B) is not particularly limited, and any acid generating agent previously proposed for chemically amplified resist compositions can be used. Examples of such acid generating agents include onium salt-based acid generating agents such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generating agents; diazomethane-based acid generating agents such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl) diazomethanes; nitrobenzyl sulfonate-based acid generating agents, iminosulfonate-based acid generating agents, disulfone-based acid generating agents, and many others. Component (B) preferably contains a compound (B1) consisting of an onium salt (hereinafter sometimes referred to as "component (B1)").

[0179] <Component (B1)> Furthermore, the resist composition according to the embodiment of the present invention contains an acid generating agent component (B) that generates acid upon exposure, and the acid generating agent component (B) may contain a compound (B1) represented by the following general formula (b-01).

[0180]

[0181] [In general formula (b-01), Rf ０１ and Rf ０２ Each of these independently represents a hydrogen atom, a fluorine atom, or a fluorinated alkyl group, and Rf ０１ , Rf ０２ At least one of them contains a fluorine atom. X represents a single bond or a divalent linking group. Y represents a cyclic group which may have substituents. m represents an integer of 1 or more, M ｍ＋ [This represents an m-valent organic cation.]

[0182] [Anion Department (Y-X-C (Rf ０１ ) (Rf ０２ ) - SO ３ － )] In the general formula (b-01), Y-X-C(Rf ０１ ) (Rf ０２ ) - SO ３ －This is a counter anion. The counter anion is not particularly limited, and those proposed as the anionic portion of acid generators for chemically amplified resist compositions can be used.

[0183] In general formula (b-01), Rf ０１ and Rf ０２ Each of these independently represents a hydrogen atom, a fluorine atom, or a fluorinated alkyl group.

[0184] Rf ０１ and Rf ０２ The fluorinated alkyl groups represented by may be linear or cyclic, and are preferably linear or branched. 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.

[0185] Examples of fluorinated alkyl groups include, for example, groups in which some or all of the hydrogen atoms constituting a linear alkyl group such as a methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, and decyl group are substituted with fluorine atoms, and groups in which some or all of the hydrogen atoms constituting a branched alkyl group such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, and a 3-methylbutyl group are substituted with fluorine atoms. Also, Rf ０１ and Rf ０２ The fluorinated alkyl groups represented by may each independently contain atoms other than fluorine, carbon, and hydrogen atoms, such as oxygen, sulfur, nitrogen, etc. In particular, Rf ０１ and Rf ０２ The fluorinated alkyl group represented by is preferably a group in which some or all of the hydrogen atoms constituting a linear alkyl group are substituted with fluorine atoms, and preferably a group in which all of the hydrogen atoms constituting a linear alkyl group are substituted with fluorine atoms (perfluoroalkyl group).

[0186] In general formula (b-01), Rf ０１ and Rf ０２ Preferably, each of these represents a fluorine atom.

[0187] In general formula (b-01), X represents a divalent linking group, and is preferably a divalent linking group containing an oxygen atom. If X is a divalent linking group containing an oxygen atom, X may contain atoms other than oxygen. Examples of atoms other than oxygen include carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms, and so on.

[0188] Examples of divalent linking groups containing an oxygen atom include non-hydrocarbon oxygen-containing linking groups such as oxygen atoms (ether bond: -O-), ester bonds (-C(=O)-O-), oxycarbonyl groups (-O-C(=O)-), amide bonds (-C(=O)-NH-), carbonyl groups (-C(=O)-), and carbonate bonds (-O-C(=O)-O-); and combinations of these non-hydrocarbon oxygen-containing linking groups with alkylene groups. Further additions to these combinations include sulfonyl groups (-SO ２ A -) may be linked. Examples of such divalent linking groups containing an oxygen atom include the linking groups represented by the following general formulas (y-al-1) to (y-al-7). Note that in the following general formulas (y-al-1) to (y-al-7), the Y in the above general formula (b-01) is bonded to V' in the following general formulas (y-al-1) to (y-al-7). １０１ That is the case.

[0189]

[0190] [In the formula, V' １０１ V' is a single bond or an alkylene group having 1 to 5 carbon atoms. １０２ [This refers to a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]

[0191] 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.

[0192] V ’１０１ and V' １０２ The alkylene group in this can be a linear alkylene group or a branched alkylene group, but a linear alkylene group is preferred.’１０１ and V' １０２ Specifically, the alkylene group in this case is the methylene group [-CH ２ -come; -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkylmethylene groups such as; ethylene groups [-CH ２ CH ２ -come; -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ２ CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ - Alkylethylene groups such as; trimethylene group (n-propylene group) [-CH ２ CH ２ CH ２ -come; -CH(CH ３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as; tetramethylene groups [-CH ２ CH ２ CH ２ CH ２ -come; -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２- Alkyltetramethylene groups such as; pentamethylene groups [-CH ２ CH ２ CH ２ CH ２ CH ２ -] are some examples. Also, V ’１０１ or V' １０２ Some of the methylene groups in the alkylene group may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is Ra' in formula (a3-r-1). ０３ A divalent group is preferred, which is obtained by removing one more hydrogen atom from a cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group), and a cyclohexylene group, a 1,5-adamantilene group, or a 2,6-adamantilene group is more preferred.

[0193] X is preferably a divalent linking group containing an ester bond or a divalent linking group containing an ether bond, more preferably a linking group represented by any of the above formulas (y-al-1) to (y-al-5), and even more preferably a linking group represented by the above formulas (y-al-1) or (y-al-3).

[0194] In general formula (b-01), Y represents a cyclic group which may have substituents. The cyclic group which may have substituents is preferably a cyclic hydrocarbon group, which may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group which does not have aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferably saturated.

[0195] The aromatic hydrocarbon group in Y is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in substituents. Specific examples of aromatic rings in the aromatic hydrocarbon group in Y include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms. Examples of heteroatoms in aromatic heterocycles include oxygen atoms, sulfur atoms, nitrogen atoms, etc. Specific examples of aromatic hydrocarbon groups in Y include groups obtained by removing one hydrogen atom from the aromatic ring (aryl groups: for example, phenyl groups, naphthyl groups, etc.), and groups in which one of the hydrogen atoms of the aromatic ring is replaced by an alkylene group (for example, arylalkyl groups such as benzyl groups, phenethyl groups, 1-naphthylmethyl groups, 2-naphthylmethyl groups, 1-naphthylethyl groups, and 2-naphthylethyl groups). 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.

[0196] The cyclic aliphatic hydrocarbon group in Y is an aliphatic hydrocarbon group that contains a ring in its structure. The cyclic aliphatic hydrocarbon group in Y preferably has 3 to 50 carbon atoms, preferably 4 to 45 carbon atoms, and more preferably 5 to 40 carbon atoms. Examples of aliphatic hydrocarbon groups containing a ring in their structure include alicyclic hydrocarbon groups (groups from which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms. The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As a monocyclic alicyclic hydrocarbon group, a group from which one or more hydrogen atoms have been removed from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically examples include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane is preferred, and as the polycycloalkane, a group having 7 to 30 carbon atoms is preferred. Among these, the polycycloalkane is adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ Polycycloalkanes having a cross-linked ring system polycyclic skeleton, such as decane and tetracyclododecane; polycycloalkanes having a fused ring system polycyclic skeleton, such as a cyclic group having a steroid skeleton, are more preferred.

[0197] In particular, as the cyclic aliphatic hydrocarbon group in Y, a group obtained by removing one or more hydrogen atoms from a monocycloalkane or polycycloalkane is preferred, a group obtained by removing one hydrogen atom from a polycycloalkane is more preferred, an adamantyl group and a norbornyl group are even more preferred, and an adamantyl group is particularly preferred.

[0198] The following are some preferred examples of cyclic aliphatic hydrocarbon groups in Y. * indicates a bond.

[0199]

[0200] 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. A linear alkylene group is preferred as the linear aliphatic hydrocarbon group, specifically a methylene group [-CH₂]. ２ -], ethylene group [- (CH ２ ) ２ -], trimethylene group [-(CH ２ ) ３ -], tetramethylene group [-(CH ２ ) ４ -], pentamethylene group [-(CH ２ ) ５ Examples include -]. The branched aliphatic hydrocarbon group, which may be bonded to the alicyclic hydrocarbon group, preferably has 2 to 10 carbon atoms, more preferably 3 to 6, even more preferably 3 or 4, and most preferably 3. A branched alkylene group is preferred as the branched aliphatic hydrocarbon group, specifically -CH(CH ３ )-,-CH(CH ２ CH ３ )-,-C(CH ３ ) ２ -, -C(CH ３ ) (CH ２ CH ３ )-,-C(CH ３ ) (CH ２ CH ２ CH ３ )-,-C(CH ２ CH ３ ) ２ - Alkyl methylene groups such as -CH(CH ３ )CH ２ -, -CH(CH ３ )CH(CH ３ )-,-C(CH ３ ) ２ CH ２ -, -CH(CH ２ CH ３ )CH ２ -, -C(CH ２ CH ３ ) ２ -CH ２ - Alkyl ethylene groups such as -CH(CH３ )CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ - Alkyl trimethylene groups such as -CH(CH ３ )CH ２ CH ２ CH ２ -ien-CH ２ CH (CH ３ )CH ２ CH ２ Examples include alkylalkylene groups such as alkyltetramethylene groups. In the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferred.

[0201] Furthermore, the cyclic hydrocarbon group in Y may contain heteroatoms, such as heterocycles. Specifically, the cyclic hydrocarbon group may be the lactone-containing cyclic group represented by the general formulas (a1-1-1) to (a1-1-7), and the -SO group represented by the general formulas (a1-2-1) to (a1-2-4). ２ - Examples include cyclic groups and heterocyclic groups represented by the following chemical formulas (r-hr-1) to (r-hr-16). In the formulas, * represents a bond attached to X in the general formula (b-01).

[0202]

[0203] Examples of the substituent on the cyclic group for Y include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxy group, a carbonyl group and a nitro group. The alkyl group as the 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 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 most preferably a methoxy group or an ethoxy group. Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable. Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group are substituted with the aforementioned halogen atoms. The carbonyl group as a substituent is a group that substitutes for the methylene group (-CH ２ -) that constitutes the cyclic hydrocarbon group.

[0204] The cyclic hydrocarbon group for Y may be a fused cyclic group including a fused ring formed by fusing an aliphatic hydrocarbon ring and an aromatic ring. Examples of the fused ring include those in which one or more aromatic rings are fused to a polycycloalkane having a crosslinked cyclic polycyclic skeleton. Specific examples of the crosslinked cyclic polycycloalkane include bicycloalkanes such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. The fused cyclic group is preferably a group containing a fused ring formed by fusing 2 or 3 aromatic rings to a bicycloalkane, and more preferably a group containing a fused ring formed by fusing 2 or 3 aromatic rings to bicyclo[2.2.2]octane. Specific examples of the fused cyclic group for Y include groups represented by the following formulas (r-br-1) to (r-br-2). In the formulas, * represents a bonding hand that bonds to X in general formula (b-01).

[0205]

[0206] Examples of substituents that the fused ring group in Y may have include alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, nitro groups, aromatic hydrocarbon groups, and alicyclic hydrocarbon groups. The alkyl groups, alkoxy groups, halogen atoms, and alkyl halides used as substituents for the fused ring group are the same as those listed above as substituents for the cyclic group in Y. Examples of aromatic hydrocarbon groups used as substituents for the fused ring group include groups obtained by removing one hydrogen atom from an aromatic ring (aryl groups: for example, phenyl groups, naphthyl groups, etc.), groups in which one hydrogen atom of the aromatic ring is replaced by an alkylene group (for example, aryl alkyl groups such as benzyl groups, phenethyl groups, 1-naphthylmethyl groups, 2-naphthylmethyl groups, 1-naphthylethyl groups, and 2-naphthylethyl groups), and heterocyclic groups represented by the above formulas (r-hr-1) to (r-hr-6). Examples of alicyclic hydrocarbon groups as substituents on the aforementioned fused ring group include monocycloalkanes such as cyclopentane and cyclohexane from which one hydrogen atom has been removed; adamantane, norbornane, isobornane, tricyclo[5.2.1.0 ２，６ ] Groups obtained by removing one hydrogen atom from polycycloalkanes such as decane and tetracyclododecane; lactone-containing cyclic groups represented by the general formulas (a1-1-1) to (a1-1-7), respectively; -SO groups represented by the general formulas (a1-2-1) to (a1-2-4), respectively. ２ - Containing cyclic groups; examples include heterocyclic groups represented by formulas (r-hr-7) to (r-hr-16), respectively.

[0207] The cyclic hydrocarbon group in Y may be a group linked by two or more linear or branched aliphatic hydrocarbon groups, which may have substituents on two or more aliphatic rings and / or aromatic rings. The linear or branched aliphatic hydrocarbon group linking the alicyclic hydrocarbon group may be a methylene group (-CH) constituting the aliphatic hydrocarbon chain. ２ The -) may be substituted with a divalent group containing a heteroatom. Examples of divalent groups containing a heteroatom include (-O-), -C(=O)-O-, -O-C(=O)-, -C(=O)-, -O-C(=O)-O-, -C(=O)-NH-, -NH-, -S-, and -S(=O).２ -, -S (=O) ２ Examples include -O-, etc.

[0208] Among the above, Y is preferably an alicyclic hydrocarbon group which may have substituents, a group obtained by removing one or more hydrogen atoms from a polycycloalkane which may have substituents, or -SO represented by any of the general formulas (a1-2-1) to (a1-2-4) above. ２ -The contained cyclic group is more preferably an adamantyl group which may have a hydroxyl group or -SO represented by the general formula (a1-2-1) above. ２ - A cyclic group is even more preferable.

[0209] Specific examples of the anionic part represented by general formula (b-01) include, for example, when X is a single bond, fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anions and perfluorobutanesulfonate anions; and when X is a divalent linking group containing an oxygen atom, the anions represented by the following formulas (an-1) to (an-3) are examples.

[0210]

[0211] [In the formula, R” １０１ R'' is an aliphatic cyclic group which may have substituents, a monovalent heterocyclic group represented by any of the above chemical formulas (r-hr-1) to (r-hr-6), or a fused cyclic group represented by the above formula (r-br-1) or (r-br-2). １０２ This includes an aliphatic cyclic group which may have substituents, a fused cyclic group represented by formula (r-br-1) or (r-br-2), a lactone-containing cyclic group represented by any of the general formulas (a1-1-1), (a1-1-3) to (a1-1-7), or -SO represented by any of the general formulas (a1-2-1) to (a1-2-4). ２ - Contains a cyclic group. R'' １０３ V'' is an aromatic cyclic group which may have substituents, or an aliphatic cyclic group which may have substituents. １０１ This is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. １０２[wherein 'v' is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms; where 'v' is an independent integer from 0 to 3, where 'q' is an independent integer from 0 to 20, and where 'n' is an independent integer from 0 to 1]

[0212] R" １０１ , R” １０２ and R” １０３ The aliphatic cyclic group which may have substituents is preferably the group exemplified as the cyclic aliphatic hydrocarbon group in Y in the general formula (b-01). Examples of substituents are the same as substituents which may substitute for the cyclic aliphatic hydrocarbon group in Y in the general formula (b-01).

[0213] R" １０３ The aromatic cyclic group in which substituents may be present is preferably one of the groups exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group in Y in the general formula (b-01). Examples of substituents include those similar to those that may substitute for the aromatic hydrocarbon group in Y in the general formula (b-01).

[0214] Among the anions in the above general formula (b-01), an anion represented by any of the above general formulas (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-1) is particularly preferred.

[0215] Specific examples of anions represented by the general formula (b-01) are shown below, but are not limited to these.

[0216]

[0217]

[0218] [Cation part: (M ｍ＋ ) １／ｍ ] In the general formula (b-01), M ｍ＋ This represents an m-valent organic cation. ｍ＋In this compound, onium cations are preferred as the organic cation, sulfonium cations, iodonium cations, and ammonium cations are more preferred, and sulfonium cations and iodonium cations are even more preferred. m is an integer of 1 or more.

[0219] Preferred cation portion ((M ｍ＋ ) １／ｍ Examples of organic cations include those represented by any of the following general formulas (ca-1) to (ca-3).

[0220]

[0221] [In general formulas (ca-1) to (ca-3), R ２０１ ~R ２０７ Each of these independently represents an optionally substituted aryl group, an optionally substituted alkyl group, or an optionally substituted alkenyl group, R ２０１ ~R ２０３ , R ２０６ ~R ２０７ These atoms may bond to each other to form a ring with the sulfur atom in the formula. ２０８ ~R ２０９ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ２１０ This may be an aryl group having a substituent, an alkyl group having a substituent, an alkenyl group having a substituent, or an -SO group having a substituent. ２ - Contains a cyclic group, L ２０１ represents -C(=O)- or -C(=O)-O-.

[0222] R ２０１ ~R ２０７ Examples of aryl groups in this compound include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. ２０１ ~R ２０７ The alkyl group in is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. ２０１ ~R ２０７ The alkenyl group in is preferably one with 2 to 10 carbon atoms. ２０１ ~R ２０７Examples of substituents that may be present include alkyl groups, halogen atoms, alkyl halides, carbonyl groups, cyano groups, amino groups, aryl groups, arylthio groups, and groups represented by any of the following formulas (ca-r-1) to (ca-r-7). Examples of aryl groups in the arylthio group as a substituent include aryl groups having 6 to 20 carbon atoms, with phenyl groups, naphthyl groups, and biphenyl groups being preferred. Examples of arylthio groups include phenylthio groups, naphthylthio groups, and biphenylthio groups.

[0223]

[0224] [In the formula, R' ２０１ Each of these is independently a hydrogen atom, an optionally substituted cyclic group, an optionally substituted linear alkyl group, or an optionally substituted linear alkenyl group.

[0225] R' ２０１ The cyclic group which may have substituents represented by is preferably a cyclic hydrocarbon group, and this cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. Examples of aromatic hydrocarbon groups include aromatic hydrocarbon rings or aryl groups obtained by removing one hydrogen atom from aromatic compounds containing two or more aromatic rings, with phenyl groups and naphthyl groups being preferred. Examples of aliphatic hydrocarbon groups include groups obtained by removing one hydrogen atom from monocycloalkanes or polycycloalkanes, with adamantyl groups and norbornyl groups being preferred.

[0226] R' ２０１The linear alkyl group, which may have substituents represented by , may be linear or branched. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15, and most preferably 1 to 10. Specific examples of linear alkyl groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, isotridecyl, tetradecyl, pentadecyl, hexadecyl, isohexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henicosyl, and docosyl groups.

[0227] R' ２０１ The linear alkenyl group, which may have substituents represented by , may be linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butenyl groups. Examples of branched alkenyl groups include 1-methylpropenyl groups and 2-methylpropenyl groups. Among the above, propenyl groups are particularly preferred as linear alkenyl groups.

[0228] R' ２０１ Examples of optionally substituted cyclic groups or optionally substituted linear alkyl groups represented by include those similar to the acid-dissociable groups described above.

[0229] R' ２０１Substituents in the cyclic group, linear alkyl group, or linear alkenyl group represented by include, for example, alkyl groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, carbonyl groups, and nitro groups. Preferably, alkyl groups have 1 to 5 carbon atoms, with methyl, ethyl, propyl, n-butyl, and tert-butyl groups being the most preferred. Preferably, alkoxy groups have 1 to 5 carbon atoms, with methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, and tert-butoxy groups being the most preferred, with methoxy and ethoxy groups being the most preferred. Examples of halogen atoms as substituents include fluorine, chlorine, bromine, and iodine atoms, with fluorine being the most preferred. Examples of alkyl halides as substituents include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, propyl, n-butyl, and tert-butyl groups, in which some or all of the hydrogen atoms are substituted with the halogen atoms.

[0230] R ２０１ ~R ２０３ , R ２０６ ~R ２０７ When these atoms bond to each other and form a ring with the sulfur atom in the formula, they can be heteroatoms such as sulfur, oxygen, and nitrogen atoms, or carbonyl groups, -SO-, -SO ２ -, -SO ３ -, -COO-, -CONH- or -N(R Ｎ )-(the R Ｎ is an alkyl group having 1 to 5 carbon atoms. ) may be bonded via functional groups such as ). The formed ring is preferably a 3 to 10-membered ring, and particularly preferably a 5 to 7-membered ring, including the sulfur atom in its ring skeleton. Specific examples of the formed ring include, for example, a thiophene ring, thiazole ring, benzothiophene ring, thianthlene ring, dibenzothiophene ring, 9H-thioxanthene ring, thioxanthone ring, thianthlene ring, phenoxatiyne ring, tetrahydrothiophenium ring, tetrahydrothiopyranium ring, thioxanium ring, and the like.

[0231] R２０８ ~R ２０９ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, with a hydrogen atom or an alkyl group having 1 to 3 carbon atoms being preferred. ２０８ ~R ２０９ However, if each element independently becomes an alkyl group, they may bond to each other to form a ring.

[0232] R ２１０ This may be an aryl group having a substituent, an alkyl group having a substituent, an alkenyl group having a substituent, or an -SO group having a substituent. ２ - Contains a cyclic group. R ２１０ Examples of aryl groups in this compound include unsubstituted aryl groups having 6 to 20 carbon atoms, with phenyl and naphthyl groups being preferred. ２１０ The alkyl group in is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms. ２１０ The alkenyl group in is preferably one with 2 to 10 carbon atoms. ２１０ In which, the substituent may be -SO ２ - In the contained cyclic group, "-SO ２ - A "cyclic group containing -SO" refers to a group whose ring skeleton contains -SO ２ This indicates a cyclic group containing a ring with -, specifically -SO ２ - is a cyclic group in which the sulfur atom (S) forms part of the cyclic skeleton. ２ The ring containing the - group is counted as the first ring. If only this ring exists, it is called a monocyclic group. If it also has other ring structures, it is called a polycyclic group regardless of those structures. -SO ２ - The contained cyclic group may be a monocyclic group or a polycyclic group. - SO ２ - The contained cyclic group, in particular, has -O-SO in its cyclic skeleton. ２ A cyclic group containing -, i.e., -O-SO ２ It is preferable that the -O-S- in the - group contains a cyclic group that includes a sultone ring, which forms part of the cyclic skeleton. ２１０ In which, the substituent may be -SO ２- The cyclic group contained is preferably the group represented by the above formula (a1-2-1). ２１０ The substituents that may be present are the above-mentioned R ２０１ ~R ２０７ Examples of substituents that may be present are shown. The cation represented by formula (ca-1) is preferably the cation represented by the following formula (b-2).

[0233]

[0234] [In formula (b-2), Rb ２０１ ~Rb ２０２ Each of these represents an aryl group which may have substituents, and Rb ２０３ Rb represents an optionally substituted aryl group, an optionally substituted alkyl group, or an optionally substituted alkenyl group. ２０１ ~Rb ２０３ These atoms may bond to each other to form a ring with the sulfur atom in formula (b-2).

[0235] Rb ２０１ ~Rb ２０２ The aryl group which may have substituents represented by the above R ２０１ ~R ２０７ This is synonymous with an aryl group which may have substituents as Rb, and the preferred example is similar. ２０３ The optionally substituted aryl group, optionally substituted alkyl group, or optionally substituted alkenyl group represented by R is as follows: ２０１ ~R ２０７ This is synonymous with an aryl group which may have substituents, an alkyl group which may have substituents, or an alkenyl group which may have substituents, and the preferred examples are similar.

[0236] Specific examples of preferred cations represented by formula (ca-1) include cations represented by any of the following formulas (ca-1-1) to (ca-1-67).

[0237]

[0238]

[0239]

[0240] [In the formula, g1, g2, and g3 represent the number of repetitions, where g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20.]

[0241]

[0242] [In the formula, R” ２０１ is a hydrogen atom or a substituent, and the substituent is R ２０１ ~R ２０７ , and R ２１０ These are the same as those listed as substituents that may be present.

[0243] Specific examples of preferred cations represented by the above formula (ca-3) include cations represented by any of the following formulas (ca-3-1) to (ca-3-6).

[0244]

[0245] In the resist composition according to the embodiment of the present invention, component (B1) may be used alone or in combination of two or more types.

[0246] In the resist composition according to the embodiment of the present invention, the content of component (B1) is preferably 1 to 60 parts by mass, more preferably 2.5 to 50 parts by mass, and even more preferably 5 to 30 parts by mass, per 100 parts by mass of component (A). When the proportion of component (B1) is within the preferred range, lithography characteristics such as roughness reduction and increased sensitivity are further improved.

[0247] Regarding component (B2), the resist composition according to the embodiment of the present invention may contain an acid generating agent component other than component (B1) (hereinafter referred to as "component (B2)"), to the extent that it does not impair the effects of the present invention. Component (B2) is not particularly limited, and any acid generating agent previously proposed for chemically amplified resist compositions can be used. Examples of such acid generating agents include onium salt-based acid generating agents such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generating agents; diazomethane-based acid generating agents such as bisalkyl or bisarylsulfonyl diazomethanes and poly(bissulfonyl) diazomethanes; nitrobenzyl sulfonate-based acid generating agents, iminosulfonate-based acid generating agents, disulfone-based acid generating agents, and many others.

[0248] In the resist composition according to the embodiment of the present invention, component (B2) may be used alone or in combination of two or more types. When the resist composition contains component (B2), the content of component (B2) in the resist composition is preferably 30 parts by mass or less, and more preferably 1 to 25 parts by mass, per 100 parts by mass of component (A). By setting the content of component (B2) in the resist composition within the above range, sufficient pattern formation is achieved. Furthermore, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, which is preferable as it results in good storage stability as a resist composition.

[0249] In the resist composition according to the embodiment of the present invention, the content of the acid generator component (B) is preferably 1 to 40 parts by mass, more preferably 2.5 to 30 parts by mass, and even more preferably 5 to 25 parts by mass, per 100 parts by mass of the base component (A). By setting the content of the acid generator component (B) in the resist composition within the above range, it becomes easier to obtain a resist composition with excellent aging stability.

[0250] ≪Component (D)≫ In this embodiment, the resist composition further contains an acid diffusion control component (D) (hereinafter referred to as "component (D)") in addition to components (A) and (B). Component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure in the resist composition. By using a resist composition containing component (D), high sensitivity can be achieved when forming a resist pattern, roughness can be reduced, and the occurrence of defects can be reduced.

[0251] Component (D) includes compound (D1) represented by the following general formula (d0-1).

[0252]

[0253] [In general formula (d0-1), R １ R represents an organic group that does not have a hydrogen atom or a nitrogen atom. ２ R represents a hydrogen atom or a hydrocarbon group. ３ [where n1 represents a substituent, and n1 represents an integer between 0 and 5.]

[0254] The nitrogen atom of compound (D1), represented by the general formula (d0-1), has its nucleophilicity appropriately adjusted by the anilide structure. Therefore, compound (D1) acts as an acid diffusion control component that traps the acid generated by exposure in the resist composition, without hindering the efficient generation of acid. Thus, when used in a resist composition, high sensitivity and reduced roughness in resist pattern formation are achieved. Furthermore, because the nucleophilicity of the nitrogen atom is appropriately adjusted, it can be used in combination with other components that would easily decompose with conventional acid diffusion control agents. Therefore, even when combined with other components that would cause defects with conventional acid diffusion control agents, it is possible to reduce defects in resist pattern formation. From the above, it is presumed that the resist composition of this embodiment can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects.

[0255] In general formula (d0-1), R １ R represents an organic group that does not contain a hydrogen atom or a nitrogen atom. １ It is preferable that the organic group does not contain a nitrogen atom.１ The organic group represented is preferably a hydrocarbon group. Examples of hydrocarbon groups include linear or branched hydrocarbon groups, or cyclic hydrocarbon groups. １ The hydrocarbon group represented by is preferably 1 to 30 carbon atoms, more preferably 5 to 30, even more preferably 7 to 20, and particularly preferably 10 to 15, from the viewpoint of adjusting the nucleophilicity of the nitrogen atom. １ The hydrocarbon group represented is preferably a linear or branched hydrocarbon group, and more preferably a linear hydrocarbon group.

[0256] R １ The linear or branched hydrocarbon group represented by may be an alkyl group, an alkenyl group, or an alkynyl group, and is preferably an alkyl group. １ The linear alkyl group represented by preferably has 1 to 30 carbon atoms, more preferably 3 to 30, even more preferably 5 to 30, particularly preferably 7 to 20, and most preferably 10 to 15. Specific examples of linear alkyl groups include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl. Among these, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl group are preferred, and n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl group are more preferred.

[0257] R １The branched alkyl group represented by preferably has 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 5 to 15, and most preferably 5 to 10. Specific examples of branched alkyl groups include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, sec-pentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, and the sec-butyl group is preferred.

[0258] The cyclic hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic or monocyclic group. An aliphatic hydrocarbon group refers to a hydrocarbon group that does not possess aromaticity. Furthermore, the aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferable.

[0259] As a monocyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferred. The monocycloalkane preferably has 3 to 6 carbon atoms, and specifically examples include cyclopentane and cyclohexane. As a polycyclic aliphatic hydrocarbon group, a group obtained by removing one hydrogen atom from a polycycloalkane is preferred, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specifically examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane, with adamantane being preferred. In the alicyclic hydrocarbon group, some of the carbon atoms constituting the ring may be substituted with heteroatoms such as oxygen atoms (-O-) and sulfur atoms (-S-). When some of the carbon atoms of the alicyclic hydrocarbon group are substituted with heteroatoms, a monocyclic group with 4 to 7 members is preferred, and a monocyclic group with 4 to 6 members is more preferred. Specific examples of the monocyclic group include tetrahydropyranyl group and tetrahydrofuranyl group.

[0260] When a cyclic hydrocarbon group becomes an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in substituents.

[0261] Examples of aromatic rings include aromatic hydrocarbon rings such as benzene, fluorene, naphthalene, anthracene, phenanthrene, and biphenyl; 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 and sulfur atoms. １ Specifically, the aromatic hydrocarbon group represented by can be a group obtained by removing one hydrogen atom from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.), or a group in which one of the hydrogen atoms of the aromatic ring is replaced by 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.), with phenyl group and naphthyl group being preferred, and phenyl group being more preferred.

[0262] R １ The cyclic hydrocarbon group represented by may have substituents. Examples of such substituents include -R Ｐ１ , -R Ｐ２ -O-R Ｐ１ , -R Ｐ２ -CO-R Ｐ１ , -R Ｐ２ -CO-OR Ｐ１ , -R Ｐ２ -O-CO-R Ｐ１ , -R Ｐ２ -OH, or -R Ｐ２ -COOH is an example. Here, R Ｐ１R is a monovalent linear saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Ｐ２ R is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. However, R Ｐ１ and R Ｐ２ Some or all of the hydrogen atoms in the chain-like saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group, and aromatic hydrocarbon group may be substituted with fluorine atoms. The cyclic hydrocarbon group may have one or more of the substituents individually, or it may have one or more of each of the substituents. Examples of monovalent chain-like saturated hydrocarbon groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and decyl groups. Examples of monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include monocyclic aliphatic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl groups; bicyclo[2.2.2]octanyl group, tricyclo[5.2.1.0 ２，６ ] Decanyl group, tricyclo[3.3.1.1 ３，７ ] Decanyl group, tetracyclo[6.2.1.1 ３，６ . 0 ２，７ Examples include polycyclic aliphatic saturated hydrocarbon groups such as dodecanyl groups and adamantyl groups. Examples of monovalent aromatic hydrocarbon groups having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring, such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

[0263] In general formula (d0-1), R ２ R represents a hydrogen atom or a hydrocarbon group. ２ R is preferably a hydrocarbon group. ２ The hydrocarbon group represented by is the aforementioned R １Examples of hydrocarbon groups similar to those represented by can be cited, and from the viewpoint of adjusting the nucleophilicity of the nitrogen atom, linear hydrocarbon groups, branched hydrocarbon groups, or monocyclic aliphatic hydrocarbon groups are preferred, linear hydrocarbon groups or branched hydrocarbon groups are more preferred, and linear hydrocarbon groups are particularly preferred.

[0264] R ２ The number of carbon atoms in the hydrocarbon group represented by is preferably 1 to 30, more preferably 3 to 30, more preferably 7 to 20, and even more preferably 10 to 15, from the viewpoint of adjusting the nucleophilicity of the nitrogen atom.

[0265] R ２ The linear hydrocarbon group represented is preferably an alkyl group having 1 to 30 carbon atoms, more preferably 3 to 30, even more preferably 5 to 30, particularly preferably 7 to 20, and most preferably 10 to 15. Specifically, preferred linear hydrocarbon groups are methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl; more preferably n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl; and even more preferably n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, or n-tetradecyl group.

[0266] R ２ The branched hydrocarbon group represented by is preferably an alkyl group having 3 to 30 carbon atoms, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 5 to 15, and most preferably 5 to 10. Specifically, the branched hydrocarbon group is preferably a sec-butyl group, an isobutyl group, a tert-butyl group, or an isopentyl group, with the sec-butyl group being preferred.

[0267] R ２The aliphatic hydrocarbon group represented by is preferably one having 3 to 6 carbon atoms, specifically the cyclopentatyl group, cyclohexyl group, etc., with the cyclohexyl group being preferred.

[0268] In embodiments of the present invention, from the viewpoint of adjusting the nucleophilicity of the nitrogen atom, in the general formula (d0-1), R １ R represents a hydrocarbon group. ２ It is preferable that R represents a hydrogen atom. In other embodiments, R １ R represents a hydrogen atom or a methyl group. ２ It is preferable that this represents a hydrocarbon group.

[0269] In general formula (d0-1), R ３ R represents a substituent. ３ Any substituent that does not affect the action of the acid diffusion control agent component can be used as the substituent represented by , and substituents that do not contain a nitrogen atom are preferred.

[0270] R ３ The substituent represented by is not particularly limited and can be various substituents such as hydrocarbon groups, alkoxy groups, halogen atoms, alkyl halides, hydroxyl groups, and esters. A hydrocarbon group, alkoxy group, or halogen atom is preferred, and a hydrocarbon group is more preferred. ３ The number of carbon atoms in the hydrocarbon group represented by is preferably 1 to 5, and more preferably 1 to 3. ３ The substituents represented by include, specifically, methyl, ethyl, propyl, butyl, and -O-CH ３ , -O-C ２ H ５ fluorine atom, chlorine atom, -OH, trifluoromethyl group, -OC(=O)CH ３ Examples include methyl group, ethyl group, -O-CH ３ Alternatively, a fluorine atom is preferred, and a methyl group is preferred. ３ If there are multiple R ３ These may be identical or different from one another.

[0271] In the general formula (d0-1), n1 represents an integer from 0 to 5. n1 is preferably 4 or less, more preferably 2 or less, even more preferably 1 or 0, and particularly preferably 0.

[0272] Specific examples of compound D1, represented by the general formula (d0-1), are given below.

[0273]

[0274] [In the formula, m1 and m2 represent the number of repetitions, each being an integer between 0 and 14.]

[0275] Component (D) may be one compound represented by the general formula (d0-1) used alone, or two or more compounds may be used in combination. When the resist composition contains component (D), the content of component (D) in the resist composition is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of component (A). If the content of component (D) is within the above range, a resist composition with particularly good lithography characteristics can be obtained.

[0276] <Optional Components> The resist composition of this embodiment may further contain components other than the above-described components (A), (B), and (D) (optional components). Examples of such optional components include the following components (E), (F), and (S).

[0277] <<Component (E): At least one compound selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives>> The resist composition of this embodiment may contain, as an optional component, at least one compound (E) selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives (hereinafter referred to as "component (E)").

[0278] Suitable organic carboxylic acids include, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, hydroxybenzoic acid, salicylic acid, phthalic acid, terephthalic acid, and isophthalic acid. Suitable phosphorus oxoacids include phosphoric acid, phosphonic acid, and phosphinic acid, with phosphonic acid being particularly preferred among these.

[0279] Examples of derivatives of phosphorus oxoacids include esters in which the hydrogen atoms of the oxoacid are substituted with hydrocarbon groups, and examples of hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms and aryl groups having 6 to 15 carbon atoms. Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate. Examples of phosphonic acid derivatives include phosphonic acid esters such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, and dibenzyl phosphonate. Examples of phosphinic acid derivatives include phosphinic acid esters and phenylphosphinic acid.

[0280] Component (E) is preferably an organic carboxylic acid, and more preferably an aromatic carboxylic acid. Specifically, preferred aromatic carboxylic acids are benzoic acid, hydroxybenzoic acid, salicylic acid, phthalic acid, terephthalic acid, and isophthalic acid, with salicylic acid being more preferred.

[0281] In the resist composition of this embodiment, component (E) may be used alone or in combination of two or more types.

[0282] If the resist composition contains component (E), the content of component (E) is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of component (A).

[0283] ≪Component (F): Fluorine-based additive component≫ The resist composition in this embodiment may further contain a fluorine-based additive component (hereinafter referred to as "component (F)") as a hydrophobic resin. Component (F) is used to impart water repellency to the resist film and improves lithography properties by being used as a resin separate from component (A).

[0284] As component (F), for example, fluorine-containing polymer compounds described in Japanese Patent Publication No. 2010-002870, Japanese Patent Publication No. 2010-032994, Japanese Patent Publication No. 2010-277043, Japanese Patent Publication No. 2011-13569, and Japanese Patent Publication No. 2011-128226 can be used.

[0285] More specifically as component (F), polymers having a constituent unit (f11) represented by the following general formula (f1-1) are mentioned. The polymers having a constituent unit (f11) represented by the following general formula (f1-1) are preferably polymers (homopolymers) consisting only of the constituent unit (f11) represented by the following formula (f1-1); copolymers of the constituent unit (f11) and the constituent unit (a3); and copolymers of the constituent unit (f11) and a constituent unit derived from acrylic acid or methacrylic acid and the constituent unit (a3). Here, the constituent unit (a3) ​​copolymerized with the constituent unit (f11) is preferably a constituent unit containing an acid-dissociable group represented by the formula (a3-r-2).

[0286]

[0287] [In the formula, R is the same as above. Rf １０２ and Rf １０３ Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf １０２ and Rf １０３ They may be the same or different. １ Rf is an integer between 0 and 5. １０１ It is an organic group containing a fluorine atom.

[0288] In the general formula (f1-1), R bonded to the carbon atom at the α-position is the same as described above. R is preferably a hydrogen atom or a methyl group.

[0289] In general formula (f1-1), Rf １０２ and Rf １０３ Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms, with fluorine being particularly preferred. Rf １０２ and Rf １０３ Examples of alkyl groups having 1 to 5 carbon atoms in R include those similar to the alkyl groups having 1 to 5 carbon atoms in R, with methyl or ethyl groups being preferred. １０２ and Rf １０３ Specifically, examples of halogenated alkyl groups having 1 to 5 carbon atoms include groups in which some or all of the hydrogen atoms of an alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc., with fluorine atoms being particularly preferred. Among these, Rf １０２ and Rf １０３ Preferably, the element is a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group.

[0290] In general formula (f1-1), n ｆ１ x is an integer from 0 to 5, preferably an integer from 1 to 3, and more preferably 1 or 2.

[0291] In general formula (f1-1), Rf １０１ This is an organic group containing a fluorine atom, and preferably a hydrocarbon group containing a fluorine atom.

[0292] The hydrocarbon group containing fluorine atoms may be linear, branched, or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and particularly preferably 1 to 10 carbon atoms.

[0293] Furthermore, in hydrocarbon groups containing fluorine atoms, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more are fluorinated, and particularly preferable that 60% or more are fluorinated, as this increases the hydrophobicity of the resist film during immersion exposure.

[0294] In particular, Rf １０１ More preferably, it is a fluorinated hydrocarbon group having 1 to 6 carbon atoms, a trifluoromethyl group, or -CH ２ -CF ３ ien-CH ２ -CF ２ -CF ３ , -CH(CF ３ ) ２ ien-CH ２ -CH ２ -CF ３ ien-CH ２ -CH ２ -CF ２ -CF ２ -CF ２ -CF ３ More preferably, -CH ２ -CF ３ That is particularly preferable.

[0295] Component (F) preferably contains a constituent unit having an acid-dissociable group, and more preferably contains a constituent unit containing an acid-dissociable group represented by formula (a3-r-2).

[0296] The weight-average molecular weight (Mw) of component (F) (based on polystyrene conversion by gel permeation chromatography) is preferably 1,000 to 50,000, more preferably 5,000 to 40,000, and most preferably 10,000 to 30,000. If the weight-average molecular weight is below the upper limit of this range, the resist composition in this embodiment has sufficient solubility in resist solvents for use as a resist, and if the weight-average molecular weight is above the lower limit of this range, the resist composition in this embodiment has good dry etching resistance and a good resist pattern cross-sectional shape.

[0297] The degree of dispersion (Mw / Mn) of component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

[0298] In the resist composition of this embodiment, component (F) may be used alone or in combination of two or more types. When the resist composition contains component (F), the content of component (F) is usually 0.5 to 10 parts by mass per 100 parts by mass of component (A).

[0299] ≪Organic Solvent Component (S)≫ The resist composition of this embodiment can be manufactured by dissolving the resist material in an organic solvent component (hereinafter referred to as "component (S)").

[0300] The (S) component can be any solvent that can dissolve each component used to form a homogeneous solution, and any solvent can be appropriately selected from those conventionally known as solvents for chemically amplified resist compositions. In the resist composition of this embodiment, the (S) component may be used alone or as a mixture of two or more solvents. Among these, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferred.

[0301] Furthermore, as component (S), a mixed solvent obtained by mixing PGMEA and a polar solvent is also preferred. The mixing ratio (mass ratio) can be appropriately determined considering the compatibility between PGMEA and the polar solvent. In addition, as component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferred. In this case, the mass ratio of the former to the latter is preferably 70:30 to 95:5.

[0302] The amount of component (S) used is not particularly limited and is set appropriately according to the coating thickness, at a concentration that can be applied to a substrate or the like. Generally, component (S) is used so that the solid content concentration of the resist composition is in the range of 0.1 to 20% by mass, preferably 0.2 to 15% by mass.

[0303] The resist composition in this embodiment may further optionally contain miscible additives, such as additional resins to improve the performance of the resist film, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation agents, dyes, and the like.

[0304] The resist composition of this embodiment contains the above-described components (A), (B), and (D), and optionally the aforementioned optional components. For example, a resist composition containing component (A), component (B), component (D), and component (F) is preferred. Furthermore, a resist composition containing component (A), component (B), component (D), component (F), and component (S) is preferred.

[0305] As described above, the resist composition of this embodiment comprises a substrate component (A), an acid generating agent component (B) that generates acid upon exposure, and an acid diffusion control component (D), wherein the acid diffusion control component (D) includes a compound (D1) represented by the general formula (d0-1). The nucleophilicity of the nitrogen atom in compound (D1) is appropriately adjusted by the anilide structure. Therefore, compound (D1) acts as an acid diffusion control agent that traps the acid generated upon exposure in the resist composition, without hindering the efficient generation of acid. Thus, it is possible to achieve both sensitivity and roughness reduction. Furthermore, because the nucleophilicity of the nitrogen atom is appropriately adjusted, it can be used in combination with other components that would easily decompose with conventional acid diffusion control agents. Therefore, even when combined with other components that would cause defects with conventional acid diffusion control agents, it is possible to reduce defects in resist pattern formation. From the above, it is presumed that the resist composition of this embodiment can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects.

[0306] [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 of the above-described embodiment, exposing the resist film, and developing the exposed resist film to form a resist pattern.

[0307] One embodiment of such a resist pattern formation method is, for example, a resist pattern formation method carried out as follows.

[0308] First, the resist composition of the above-described embodiment is applied onto a support using a spinner or the like, and a bake (post-apply bake (PAB)) treatment is performed for 40 to 120 seconds, preferably 50 to 90 seconds, at a temperature of, for example, 80 to 150°C, to form a resist film. Next, the resist film is subjected to selective exposure using an exposure apparatus such as an electron beam lithography apparatus or an EUV exposure apparatus, either through exposure via a mask (mask pattern) with a predetermined pattern formed on it, or by direct irradiation with an electron beam without going through a mask pattern. After that, a bake (post-exposure bake (PEB)) treatment is performed for 40 to 120 seconds, preferably 50 to 90 seconds, at a temperature of, for example, 80 to 150°C.

[0309] Next, the resist film is developed. In the case of an alkaline development process, an alkaline developer is used for development, and in the case of a solvent development process, a developer containing an organic solvent (organic developer) is used. After development, rinsing is preferably performed. In the case of an alkaline development process, rinsing with pure water is preferred, and in the case of a solvent development process, rinsing with a rinsing solution containing an organic solvent is preferred.

[0310] In the solvent development process, after the development or rinsing process, the developer or rinse solution adhering to the pattern may be removed using a supercritical fluid. After the development or rinsing process, drying is performed. In some cases, a bake process (post-bake) may be performed after the development process. In this way, a resist pattern can be formed.

[0311] The support material is not particularly limited and can be any conventionally known material, such as a substrate for electronic components or a substrate on which a predetermined wiring pattern has been formed. More specifically, examples of support materials include silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, and glass substrates. As for the wiring pattern material, for example, copper, aluminum, nickel, and gold can be used. The wavelength used for exposure is not particularly limited and can be performed using radiation such as ArF excimer lasers, KrF excimer lasers, F2 excimer lasers, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, and soft X-rays. The resist composition is highly useful for use with KrF excimer lasers, ArF excimer lasers, EB, or EUV.

[0312] The method for exposing the resist film may be conventional exposure (dry exposure) performed in an inert gas such as air or nitrogen, or liquid immersion exposure (liquid immersion lithography), but liquid immersion exposure is preferred. Liquid immersion exposure is an exposure method in which the space between the resist film and the lens at the lowest position of the exposure apparatus is filled in advance with a solvent (liquid immersion medium) having a refractive index greater than that of air, and exposure (immersion exposure) is performed in that state. As the liquid immersion medium, a solvent having a refractive index greater than that of air and smaller than that of the resist film to be exposed is preferred. 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, hydrocarbon-based solvents, etc. Water is preferably used as the liquid immersion medium.

[0313] Examples of alkaline developers used in the alkaline development process include 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution.

[0314] The organic solvent contained in the organic developer solution used in the solvent development process can be any solvent capable of dissolving component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specifically, examples of organic solvents include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, as well as hydrocarbon solvents. Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butanoate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate.

[0315] Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, and butyronitrile.

[0316] Organic developers may contain known additives as needed. Examples of such additives include surfactants. While not particularly limited, surfactants such as ionic or nonionic fluorine-based and / or silicone-based surfactants can be used.

[0317] The development process can be carried out by known development methods, such as immersing the support in developer for a certain period of time (dip method), piling up developer on the surface of the support by surface tension and leaving it still for a certain period of time (paddle method), spraying developer onto the surface of the support (spray method), or continuously dispensing developer while scanning a developer dispensing nozzle at a constant speed onto a support rotating at a constant speed (dynamic dispensing method).

[0318] Rinsing (cleaning) using a rinsing solution can be carried out by known rinsing methods. Examples of such rinsing methods include continuously dispensing the rinsing solution onto a support rotating at a constant speed (rotary coating method), immersing the support in the rinsing solution for a certain period of time (dip method), and spraying the rinsing solution onto the surface of the support (spray method).

[0319] The resist compositions of the embodiments described above, and the various materials used in the pattern forming methods of the embodiments described above (for example, resist solvents, developers, rinse solutions, anti-reflective film forming compositions, topcoat forming compositions, etc.) are preferably free of impurities such as metals, metal salts containing halogens, acids, alkalis, sulfur atoms, or phosphorus atoms. Examples of metal atom-containing impurities include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, or salts thereof. The content of impurities in these materials is preferably 200 ppb or less, more preferably 1 ppb or less, even more preferably 100 ppt (parts per trillion) or less, particularly preferably 10 ppt or less, and most preferably substantially free (below the detection limit of the measuring device).

[0320] In the resist pattern formation method of this embodiment described above, the resist composition according to the embodiment of the present invention described above is used. This resist composition can achieve high sensitivity in resist pattern formation, reduce roughness, and reduce the occurrence of defects, so that a resist pattern with a good shape can be formed by the pattern formation method of the embodiment.

[0321] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0322] Each polymer compound was synthesized using monomers that derive the constituent units of polymer compounds A-1 to A-3 shown below, in predetermined molar ratios. Regarding the obtained polymer compounds, １３The copolymerization composition ratio (molar ratio of each constituent unit in the polymer compound) of the polymer compound, determined by C-NMR, and the weight-average molecular weight (Mw) and molecular weight dispersion (PDI) (Mw / Mn) in terms of standard polystyrene, determined by GPC measurement, are also shown.

[0323]

[0324] <Preparation of Resist Compositions> (Examples 1-22, Comparative Examples 1-14) The components shown in Tables 1-2 below were mixed and dissolved in solvent S-1 to prepare the resist compositions for each example.

[0325]

[0326]

[0327] In Tables 1 and 2, each abbreviation has the following meaning. The numbers in brackets [ ] represent the amount (parts by mass) of the ingredients.

[0328] A-1 to A-3: Base component consisting of polymer compounds represented by the above chemical formulas A-1 to A-3. B-1 to B-2: Acid generating agent component consisting of compounds represented by the following chemical formulas B-1 to B-2. D1-1 to D1-16: Acid diffusion control component consisting of compounds represented by the following chemical formulas D1-1 to D1-16. D2-1 to D2-12: Acid diffusion control component consisting of compounds represented by the following chemical formulas D2-1 to D2-12. F-1 to F-2: Hydrophobic resin consisting of polymer compounds represented by the following chemical formulas F-1 to F-2. １３ The copolymerization composition ratio of the polymer compound determined by C-NMR (the proportion (molar ratio) of each constituent unit in the polymer compound), the weight-average molecular weight (Mw) and molecular weight dispersion (PDI) (Mw / Mn) in terms of standard polystyrene, determined by GPC measurement, are also shown. S-1: A mixed solvent of propylene glycol monomethyl ether acetate (PGMEA) / propylene glycol monomethyl ether (PGME) / cyclohexanone = 45 / 30 / 25 by mass ratio.

[0329]

[0330]

[0331]

[0332]

[0333]

[0334] <Formation of Resist Patterns> An organic anti-reflective coating composition "ARC95" (manufactured by Brewer Science Co., Ltd.) was applied to a 12-inch silicon wafer using a spinner, and then baked on a hot plate at 205°C for 60 seconds to dry it, thereby forming an organic anti-reflective coating with a thickness of 98 nm. Each resist composition was applied to the anti-reflective coating using a spinner, and then pre-baked (PAB) on a hot plate at 100°C for 60 seconds and dried to form a resist coating with a thickness of 110 nm.

[0335] Using an immersion ArF exposure system XT1900Gi [manufactured by ASML; NA (numerical aperture) = 1.35, Dipole (in / out = 0.65 / 0.85), TE-pol, immersion medium: water], an ArF excimer laser (193 nm) was selectively irradiated through a photomask (6% halftone). Subsequently, PEB treatment was performed at 90°C for 60 seconds. Next, alkaline development was performed at 23°C for 10 seconds with a 2.38 mass% TMAH aqueous solution (product name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.), followed by a 15-second rinse with pure water and complete drying. As a result, in all examples, a 1:1 line-and-space (LS) pattern with a line width of 40 nm and a pitch of 80 nm was formed.

[0336] [Evaluation of Sensitivity (Optimal Exposure Dose Eop)] The optimal exposure dose Eop (mJ / cm²) for forming a 1:1 LS pattern with a line width of 40 nm and a pitch of 80 nm in the above <Formation of Resist Pattern> is... ２ The following was calculated. The results are shown in Tables 1 and 2 above.

[0337] [Evaluation of LWR (Line-Wide Roughness)] For the LS pattern formed in the above <Formation of Resist Pattern>, 3σ, a measure of LWR, was determined. This is shown in Tables 1 and 2 as "LWR (nm)". "3σ" represents three times the standard deviation (σ) (unit: nm) obtained from the measurement results of 400 line positions measured along the longitudinal direction of the line using a length-measuring SEM (scanning electron microscope, acceleration voltage 500V, product name: CG-5000, Hitachi High-Technologies Corporation). The smaller the value of 3σ, the smaller the roughness of the line sidewalls, and the more uniform the width of the LS pattern obtained.

[0338] For the aforementioned LS patterns, the total number of defects within the wafer was measured using a surface defect observation device (product name: KLA2905, manufactured by KLA-Tencor). Ten measurements were taken for each sample, and the evaluation result of the average value is shown in the table as "defects". Tables 1 and 2 show the results as follows: 20 or fewer defects are marked with ○, 21 to 49 defects with ×, and 50 or more defects with ××.

[0339] The results shown in Tables 1 and 2 confirm that the resist compositions of the embodiments to which the present invention is applied can provide resist compositions that can achieve high sensitivity, reduced roughness, and reduced defect occurrence in the formation of resist patterns.

[0340] The present invention provides a resist composition that can achieve high sensitivity, reduce roughness, and reduce the occurrence of defects in resist pattern formation, as well as a resist pattern formation method using the resist composition.

[0341] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on Japanese Patent Application No. 2025-052261, filed on 26 March 2025, the contents of which are incorporated herein by reference.

Claims

1. A resist composition which generates an acid upon exposure and whose solubility in a developer changes due to the action of an acid, comprising a base material component (A) whose solubility in a developer changes due to the action of an acid, an acid generator component (B) which generates an acid upon exposure, and an acid diffusion control component (D), wherein the acid diffusion control component (D) comprises a compound (D1) represented by the following general formula (d0-1). [In general formula (d0-1), R １ represents a hydrogen atom or an organic group having no nitrogen atom, R ２ represents a hydrogen atom or a hydrocarbon group, R ３ represents a substituent, and n1 represents an integer of 0 to 5.]] 2. The R in the general formula (d0-1) １ The resist composition according to claim 1, wherein the organic group represented by is a hydrocarbon group.

3. The R in the general formula (d0-1) １ The resist composition according to claim 1, wherein represents a linear or branched hydrocarbon group.

4. The R in the general formula (d0-1) １ The resist composition according to claim 1, wherein is a hydrocarbon group having 5 to 30 carbon atoms.

5. The R in the general formula (d0-1) ２ The resist composition according to claim 1 or 2, wherein represents a linear or branched hydrocarbon group.

6. The R in the general formula (d0-1) ２ The resist composition according to claim 1 or 2, wherein represents a hydrocarbon group having 3 to 30 carbon atoms.

7. The resist composition according to claim 1 or 2, further comprising a fluorine-based additive component (F).

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

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