KR20170070843A - Resist composition, method of forming resist pattern, compound and acid generator - Google Patents

Abstract

A novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a method of forming a resist pattern using the resist composition.
(Solution) A resist composition containing a compound represented by the general formula (b1). In formula (b1), R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 Is a benzene ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings. R ^b21 and R ^b22 represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. X ^- represents the counter no (except BF ₄ ^- ).
[Chemical Formula 1]

Description

RESIST COMPOSITION AND METHOD FOR FORMING RESIST PATTERN, COMPOUND AND ACID GENERATOR,

The present invention relates to a resist composition and a method for forming a resist pattern, and to a compound and an acid generator.

In lithography, for example, a resist film made of a resist material is formed on a substrate, a selective exposure is performed on the resist film, and a development process is performed to form a resist pattern of a predetermined shape on the resist film . A resist material in which the exposure part of the resist film changes in characteristics to be dissolved in the developing solution is referred to as a positive type and a resist material which changes to a property that the exposed part of the resist film does not dissolve in the developing solution is referred to as a negative type.

BACKGROUND ART [0002] In recent years, in the production of semiconductor devices and liquid crystal display devices, pattern miniaturization has progressed rapidly by the progress of lithography technology. In general, the exposure light source is shortened (made into a high energy) by the technique of micronization. Specifically, conventionally, ultraviolet rays represented by g-line and i-line have been used, but now, mass production of semiconductor devices using KrF excimer laser or ArF excimer laser has been carried out. EUV (extreme ultraviolet), EB (electron beam), X-ray and the like having a shorter wavelength (high energy) than these excimer lasers have also been studied.

Resist materials are required to have lithography properties such as sensitivity to resolution of these exposure light sources and resolving ability to reproduce patterns of fine dimensions.

As a resist material satisfying such a demand, a chemically amplified resist composition containing a base component whose solubility in a developing solution changes by the action of an acid and an acid generator component which generates an acid by exposure is conventionally used .

For example, when the developer is an alkali developing solution (alkali developing process), the positive chemical amplification type resist composition includes a resin component (base resin) that increases the solubility in an alkali developing solution by the action of an acid, Is generally used. When a resist film formed using such a resist composition is subjected to selective exposure at the time of forming a resist pattern, acid is generated from the acid generator component in the exposed portion, and the polarity of the base resin is increased by the action of the acid, The exposed portion of the resist film becomes soluble in the alkali developing solution. As a result, a positive pattern in which the unexposed portion of the resist film remains as a pattern is formed by alkali development.

On the other hand, when such a chemically amplified resist composition is applied to a solvent developing process using a developing solution (organic developing solution) containing an organic solvent, the solubility of the organic developing solution relatively decreases as the polarity of the base resin increases, A negative resist pattern is formed in which the unexposed portion of the resist film is dissolved or removed by the organic developer to leave as an exposed pattern portion of the resist film. As described above, the solvent developing process for forming the negative resist pattern is sometimes referred to as a negative developing process.

The base resin used in the chemically amplified resist composition generally has a plurality of constituent units for the purpose of improving lithography characteristics and the like.

For example, in the case of a resin component whose solubility in an alkali developing solution is increased by the action of an acid, a constitutional unit containing an acid-decomposable group which is decomposed by the action of an acid generated from an acid generator or the like and increases in polarity is used, In addition, a constitutional unit containing a lactone-containing cyclic group, a constitutional unit containing a polar group such as a hydroxyl group, and the like are used in combination.

 Further, in the formation of the resist pattern, the behavior of the acid generated from the acid generator component by exposure becomes a factor that greatly affects the lithography characteristics.

As the acid generator used in the chemically amplified resist composition, various ones have been proposed so far. For example, onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, diazomethane acid generators, nitrobenzyl sulfonate acid generators, iminosulfonate acid generators And a disulfone-based acid generator are known.

As the onium salt-based acid generator, those having an onium ion such as triphenylsulfonium are mainly used in the cation portion. In general, an alkylsulfonic acid ion or a fluorinated alkylsulfonic acid ion in which a part or all of the hydrogen atoms of the alkyl group are substituted with a fluorine atom is used as the anion of the onium salt-based acid generator.

 On the other hand, an onium salt-based acid generator system having an onium ion having a dibenzothiophene structure has been proposed as a cationization unit of an onium salt-based acid generator in order to improve lithography characteristics in the formation of a resist pattern (for example, , See Patent Document 1).

Japanese Patent Application Laid-Open No. 2008-273912

While advances in lithography technology and finer patterning of resist patterns are progressing, for example, in the case of electron beam or EUV lithography, it is aimed to form fine patterns of several ten nm. As the resist pattern dimension is reduced, the resist composition is required to have a high sensitivity to an exposure light source.

However, in a resist composition containing the conventional onium salt-based acid generators as described above, it is difficult to obtain a desired resist pattern shape and the like by increasing the sensitivity to an exposure light source such as EUV, It was difficult to satisfy.

The present invention has been made in view of the above circumstances and provides a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a resist pattern forming method using the resist composition And to provide an image processing apparatus.

In order to solve the above problems, the present invention employs the following configuration.

That is, the first aspect of the present invention is a resist composition which generates an acid upon exposure to light and changes the solubility in a developer by the action of an acid, wherein a base component (A) whose solubility in a developer changes by the action of an acid ) And a compound (B1) represented by the following general formula (b1).

[Chemical Formula 1]

^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 (provided that the aromatic ring is benzene Ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).]

A second aspect of the present invention is a method for forming a resist pattern, comprising the steps of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film, and developing the resist film after exposure to form a resist pattern And a resist pattern forming method.

A third aspect of the present invention is a compound represented by the following general formula (b1).

(2)

^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 (provided that the aromatic ring is benzene Ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).]

A fourth aspect of the present invention is the acid generator which is characterized by comprising the compound according to the third aspect.

According to the present invention, it is possible to provide a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a method of forming a resist pattern using the resist composition.

According to the resist composition of the present invention, high sensitivity can be obtained in forming a resist pattern, and a resist pattern having a good shape can be formed.

In the present specification and claims, the term " aliphatic " is defined as meaning a group, compound, or the like having no aromaticity as a relative concept to an aromatic.

The "alkyl group" is intended to include linear, branched, and cyclic monovalent saturated hydrocarbon groups, unless otherwise specified. The alkyl group in the alkoxy group is also the same.

The " alkylene group " includes straight-chain, branched-chain and cyclic divalent saturated hydrocarbon groups, unless otherwise specified.

The "halogenated alkyl group" is a group in which a part or all of the hydrogen atoms of the alkyl group are substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

The "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which a part or all of the hydrogen atoms of the alkyl group or alkylene group are substituted with fluorine atoms.

"Constituent unit" means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).

Includes the case of substituting a hydrogen atom (-H) with a monovalent group and the case of substituting a methylene group (-CH ₂ -) with a divalent group when describing "may have a substituent".

&Quot; Exposure " is a concept including the entire irradiation of radiation.

The term "structural unit derived from an acrylate ester" means a structural unit constituted by cleavage of an ethylenic double bond of an acrylate ester.

"Acrylic acid ester" is a compound in which a hydrogen atom at the terminal of a carboxyl group of acrylic acid (CH ₂ ═CH-COOH) is substituted with an organic group.

The acrylate ester may have a hydrogen atom bonded to the carbon atom at the? -Position thereof substituted with a substituent. The substituent (R ^{? 0} ) for substituting a hydrogen atom bonded to the carbon atom at the ^{? -Position} is an atom or a group other than a hydrogen atom, and examples thereof include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms have. Also, itaconic acid diesters in which a substituent (R ^{? 0} ) is substituted with a substituent containing an ester bond, or an ^? -Hydroxyacrylic ester in which a substituent (R ^{? 0} ) is substituted with a hydroxyalkyl group or a group in which the hydroxyl group is substituted do. The carbon atom at the? -Position of the acrylic ester refers to a carbon atom to which a carbonyl group of acrylic acid is bonded, unless otherwise specified.

Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the? -Position is substituted with a substituent is sometimes referred to as an? -Substituted acrylate ester. In some cases, an acrylic acid ester and an alpha-substituted acrylic acid ester are collectively referred to as " (alpha-substituted) acrylic ester ".

The term " structural unit derived from acrylamide " means a structural unit comprising an ethylene double bond of acrylamide cleaved.

The acrylamide may have a hydrogen atom bonded to the carbon atom at the? -Position thereof substituted with a substituent, and one or both of the hydrogen atoms of the amino group of the acrylamide may be substituted with a substituent. The carbon atom at the? -Position of acrylamide refers to a carbon atom to which a carbonyl group of acrylamide is bonded, unless otherwise specified.

Examples of the substituent substituting the hydrogen atom bonded to the carbon atom at the? -Position of the acrylamide include those exemplified as the substituent at the ^{? -Position} (substituent (R ^{? 0} )) in the? -Substituted acrylate ester.

The term "structural unit derived from hydroxystyrene" means a structural unit constituted by cleavage of an ethylenic double bond of hydroxystyrene. The term " structural unit derived from hydroxystyrene derivative " means a structural unit constituted by cleavage of an ethylenic double bond of a hydroxystyrene derivative.

The term " hydroxystyrene derivative " includes not only hydrogen atoms at the alpha -position of hydroxystyrene but also other substituents such as alkyl groups and halogenated alkyl groups, and derivatives thereof. Examples of the derivatives thereof include those obtained by substituting the hydrogen atom of the hydroxyl group of the hydroxystyrene which may be substituted with a hydrogen atom at the α-position with an organic group, a benzen ring of hydroxystyrene where the hydrogen atom at the α- And those having a substituent other than a hydroxyl group bonded thereto. The? Position (carbon atom at?) Refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

Examples of the substituent substituting the hydrogen atom at the? -Position of hydroxystyrene include the same ones exemplified as the substituent at the? -Position in the? -Substituted acrylate ester.

The term " structural unit derived from vinylbenzoic acid or vinylbenzoic acid derivative " means a structural unit constituted by cleavage of the ethylenic double bond of vinylbenzoic acid or vinylbenzoic acid derivative.

The term " vinylbenzoic acid derivative " means a vinylbenzoic acid in which hydrogen atoms at the alpha -position of vinylbenzoic acid are substituted with other substituents such as an alkyl group and a halogenated alkyl group, and derivatives thereof. Examples of the derivatives thereof include those obtained by substituting hydrogen atoms of the carboxyl groups of vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with organic groups, benzene rings of vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with substituents, And those having a substituent other than a carboxyl group bonded thereto. The? Position (carbon atom at?) Refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

The term " styrene " includes the concept that hydrogen atoms at the [alpha] -position of styrene and styrene are substituted with other substituents such as an alkyl group and a halogenated alkyl group.

The term " styrene derivative " includes not only the hydrogen atoms at the [alpha] -position of styrene substituted with other substituents such as an alkyl group and a halogenated alkyl group, and derivatives thereof. Examples of the derivatives thereof include those in which a substituent is bonded to a benzene ring of hydroxystyrene in which a hydrogen atom at the? Position may be substituted with a substituent. The? Position (carbon atom at?) Refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

"Constituent unit derived from styrene" and "constituent unit derived from styrene derivative" refer to a constituent unit in which an ethylene double bond of styrene or styrene derivative is cleaved.

The alkyl group as the substituent at the? -Position is preferably a linear or branched alkyl group, and more specifically, an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, Butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group).

 Specific examples of the halogenated alkyl group as the substituent at the? -Position include a group obtained by substituting a part or all of the hydrogen atoms of the alkyl group as the substituent at the? -Position with a halogen atom. The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable.

 Specific examples of the hydroxyalkyl group as the substituent at the? -Position include a group in which a part or all of the hydrogen atoms of the "alkyl group as the substituent at the? -Position" are substituted with hydroxyl groups. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.

(Resist Composition)

The resist composition according to the first embodiment of the present invention generates an acid by exposure and changes the solubility in the developer by the action of an acid.

In one embodiment of such a resist composition, a base component (A) (hereinafter also referred to as a "component (A)") in which the solubility in a developer varies by the action of an acid, and a compound represented by the general formula (b1) B1) (hereinafter, also referred to as " component (B1) ").

When a resist film is formed by using the resist composition of the present embodiment and selectively exposed to the resist film, an acid is generated from the component (B1) in the exposed portion of the resist film, and the component (A) The solubility of the component (A) in the unexposed portion of the resist film does not change, and the difference in solubility in the developer between the exposed portion and the unexposed portion occurs. Therefore, when the resist film is developed, if the resist composition is a positive type, the resist film exposure part is dissolved and removed to form a positive resist pattern. If the resist composition is negative, the resist film unexposed area is dissolved and removed A negative resist pattern is formed.

In the present specification, a resist composition that forms a positive resist pattern by dissolving and removing the resist film exposure portion is referred to as a positive resist composition, and a resist composition that forms a negative resist pattern by dissolving and removing the resist film unexposed portion is referred to as a negative resist Composition.

The resist composition of the present embodiment may be a positive resist composition or a negative resist composition.

 The resist composition of the present embodiment may also be used for an alkali development process using an alkali developer for development processing at the time of forming a resist pattern and may be a solvent developing process using an organic solvent (organic developing solution) .

The resist composition of the present embodiment has an acid-generating ability to generate an acid upon exposure. In addition to the component (B1), the component (A) may generate an acid by exposure.

 When the component (A) generates an acid by exposure, the component (A) becomes a base component which generates an acid upon exposure and has a solubility in the developer changed by the action of an acid. When the component (A) generates an acid upon exposure and the solubility of the component in the developer changes due to the action of an acid, the component (A1) described later generates an acid by exposure, And is preferably a polymer compound whose solubility in a developer varies depending on the action of an acid. As such a polymer compound, a resin having a constituent unit capable of generating an acid upon exposure can be used. As the constituent unit for generating an acid upon exposure, known ones can be used.

≪ Component (A) >

The component (A) is a base component in which the solubility in the developer is changed by the action of an acid.

In the present invention, the " base component " is an organic compound having film-forming ability, preferably an organic compound having a molecular weight of 500 or more. When the molecular weight of the organic compound is 500 or more, the film forming ability improves, and a nano-level resist pattern is easily formed.

The organic compound used as the base component is roughly classified into a non-polymer and a non-polymer.

As the non-polymeric polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, the term " low molecular weight compound " refers to a non-polymeric substance having a molecular weight of 500 or more and less than 4000.

As the polymer, usually those having a molecular weight of 1000 or more are used. Hereinafter, the term "resin", "polymer compound" or "polymer" refers to a polymer having a molecular weight of 1,000 or more.

As the molecular weight of the polymer, a mass average molecular weight in terms of polystyrene by GPC (Gel Permeation Chromatography) is used.

When the resist composition of the present embodiment is a "negative resist composition for alkali development process" in which a negative resist pattern is formed in an alkali developing process, or when a negative resist composition for forming a positive resist pattern in a solvent developing process (Hereinafter referred to as " component (A-2) ") is preferably used as the component (A) in the positive resist composition , And a crosslinking agent component is further blended. When such an acid is generated from the component (B1) by exposure, for example, such a resist composition causes crosslinking between the component (A-2) and the crosslinking agent component due to the action of the acid, and as a result, solubility in an alkali developer (Solubility in an organic developer is increased). Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed, the resist film exposed portion is changed to be poorly soluble (soluble in an organic developer) to an alkali developer, Since the unexposed portion does not remain soluble (insoluble in an organic developer) with respect to the alkali developer, a negative resist pattern is formed by developing with an alkaline developer. At this time, a positive resist pattern is formed by developing with an organic developer.

As a preferable component of the component (A-2), a resin soluble in an alkali developer (hereinafter referred to as " alkali-soluble resin ") is used.

As the alkali-soluble resin, for example, an alkylester of? - (hydroxyalkyl) acrylic acid or? - (hydroxyalkyl) acrylic acid (preferably an alkylester of 1 to 20 carbon atoms, 5); a resin having a constituent unit derived from at least one selected from the group consisting of an acrylic resin having a sulfonamide group-substituted hydrogen atom bonded to the carbon atom at the? -Position having a sulfonamide group, Or a polycycloolefin resin, which is disclosed in U.S. Patent Nos. 6949325, 2005-336452, and 2006-317803, in which a hydrogen atom containing a fluorinated alcohol and bonded to a carbon atom at the [alpha] An acrylic resin which may be substituted with a fluorinated alcohol such as a fluorinated alcohol described in JP-A-2006-259582 It is preferable in that such a polycycloolefin resin, the swelling can be formed with less good resist pattern.

 The above-mentioned? - (hydroxyalkyl) acrylic acid may be obtained by copolymerizing an acrylic acid in which a hydrogen atom is bonded to a carbon atom at the? -Position to which a carboxyl group is bonded, among the acrylic acid in which a hydrogen atom bonded to the carbon atom at? refers to one or both of? -hydroxyalkyl acrylic acid to which a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) is bonded to a carbon atom at? -position.

As the crosslinking agent component, it is preferable to use, for example, an amino-based crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group, or a melamine-based crosslinking agent in view of easy formation of a good resist pattern with less swelling. The blending amount of the crosslinking agent component is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the alkali-soluble resin.

When the resist composition of the present embodiment is a "positive resist composition for alkali development process" in which a positive resist pattern is formed in an alkali developing process, or when a negative resist pattern is formed in a solvent development process (Hereinafter referred to as " component (A-1) ") in which the polarity increases due to the action of an acid is preferably used as the component (A) ) Is used. By using the component (A-1), since the polarity of the base component changes before and after the exposure, a good development contrast can be obtained not only in the alkali development process but also in the solvent development process.

In the case of applying the alkali developing process, the component (A-1) is poorly soluble in an alkali developing solution before exposure. For example, when an acid is generated from the component (B1) by exposure, And the solubility in an alkali developing solution is increased. Therefore, in the formation of the resist pattern, when the resist film is selectively exposed to a resist film obtained by applying the resist composition on a support, the resist film exposed portion changes from poorly soluble to soluble with respect to the alkali developer, Is not changed to remain alkali-resistant, so that a positive resist pattern is formed by alkali development.

On the other hand, when a solvent developing process is applied, the component (A-1) has high solubility in an organic developing solution before exposure, and when an acid is generated from the component (B1) by exposure, the polarity of the component , The solubility in an organic developer is decreased. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed, the resist film exposed portion changes from soluble to poorly soluble in the organic developer, The resist pattern does not change to remain soluble. Therefore, by developing with an organic developing solution, a contrast can be obtained between the exposed portion and the unexposed portion, and a negative resist pattern is formed.

In the resist composition of the present embodiment, the component (A) is preferably the component (A-1). That is, the resist composition of the present embodiment can be applied to a "positive resist composition for alkali development process" for forming a positive resist pattern in an alkali developing process, or a "positive resist composition for forming a negative resist pattern" Negative resist composition for process "

 As the component (A), a polymer compound and / or a low-molecular compound is used.

 When the component (A) is a component (A-1), the component (A-1) preferably contains a polymer compound and the constituent unit (a1 ) (Hereinafter also referred to as " component (A1) ").

· For the component (A1)

The component (A1) is a polymer compound having the structural unit (a1).

As the component (A1), it is preferable to use, in addition to the structural unit (a1), a polymer compound having a structural unit (a2) containing a lactone-containing cyclic group, -SO ₂ -containing cyclic group or a carbonate- .

 In addition to the structural unit (a1) or the structural unit (a1) and the structural unit (a2), a structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group (excluding those corresponding to the structural unit (a1) or the structural unit (a2)).

 In addition to the constituent units (a1) to (a3), the constituent unit (A1) includes a constituent unit (a4) containing an aliphatic cyclic group of acid-labile properties, a constituent unit represented by the general formula (a9-1) (St) derived from styrenes such as styrenes, styrenes, and styrenes, constituent units generating an acid upon exposure, and the like.

&Quot; Construction unit (a1) "

The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid.

The "acid-decomposable group" is an acid-decomposable group capable of cleaving at least a part of bonds in the structure of the acid decomposable group by the action of an acid.

Examples of the acid decomposable group whose polarity is increased by the action of an acid include groups which are decomposed by the action of an acid to generate a polar group.

Examples of the polar group include a carboxyl group, a hydroxyl group, an amino group, and a sulfo group (-SO ₃ H). Among them, a polar group containing -OH (hereinafter sometimes referred to as "OH-containing polar group") in the structure is preferable, a carboxyl group or a hydroxyl group is more preferable, and a carboxyl group is particularly preferable.

More specific examples of the acid decomposable group include groups in which the polar group is protected with an acid dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid dissociable group).

Herein, "acid dissociable group" means (i) a group having acid dissociable property by which the bond between the acid dissociable group and the atom adjacent to the acid dissociable group can be cleaved by the action of an acid, or Refers to both groups in which a bond between an acid dissociable group and an atom adjacent to the acid dissociable group can be cleaved by the occurrence of a decarboxylation reaction after cleavage of a part of bonds by the action of an acid.

The acid dissociable group constituting the acid-decomposable group is required to be a group having a lower polarity than the polar group generated by dissociation of the acid dissociable group, and when the acid dissociable group is dissociated by the action of an acid, Polarity with higher polarity than genitalia is generated and polarity is increased. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developing solution changes relatively. When the developing solution is an alkaline developing solution, the solubility increases. When the developing solution is an organic developing solution, the solubility decreases.

Examples of acid dissociable groups include those proposed so far as acid dissociable groups of a base resin for a chemically amplified resist composition.

Acid-dissociable group of a base resin for a chemically amplified resist composition, and specifically, there are a "acetal type acid dissociable group", "a tertiary alkyl ester type acid dissociable group", a "tertiary Alkyloxycarbonyl acid dissociable group ".

· Acetal type acid dissociation type:

Examples of the acid dissociable group for protecting the carboxyl group or the hydroxyl group in the polar group include an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as an "acetal type acid dissociable group" ).

(3)

[And wherein, Ra ^'1, Ra' ² is a hydrogen atom or an alkyl group, Ra ^'3 is a hydrocarbon group, Ra' ³ are combined as one of Ra ^'1, Ra' ² may also form a ring.]

In the formula (a1-r-1), at least one of Ra ' ¹ and Ra' ² is preferably a hydrogen atom, and more preferably both hydrogen atoms.

When Ra ' ¹ or Ra' ² is an alkyl group, the alkyl group may be the same as the alkyl group exemplified as a substituent which may be bonded to the carbon atom at the α-position in the explanation of the α-substituted acrylate ester. An alkyl group having a carbon number of 5 to 5 is preferable. Specifically, the alkyl group is preferably a linear or branched alkyl group. More specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group and a neopentyl group, More preferably a methyl group is particularly preferable.

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

The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group and an n-pentyl group. Among them, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples thereof include isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl, 1,1-diethylpropyl and 2,2-dimethylbutyl. .

When Ra ' ³ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polycyclic group, or a monocyclic group.

The aliphatic hydrocarbon group which is a monocyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like.

The aliphatic hydrocarbon group which is a polycyclic group is preferably a group in which one hydrogen atom has been removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

When the cyclic hydrocarbon group of Ra ' ³ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 < [pi] > electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group in Ra ' ³ include a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring (an aryl group or a heteroaryl group), an aromatic compound containing two or more aromatic rings A group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (e.g., a benzyl group, a phenethyl group, Naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, and other arylalkyl groups), and the like. The number of carbon atoms of the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The cyclic hydrocarbon group in Ra ' ³ may have a substituent. As a substituent is, for example, ^P1 -R, -R -OR ^{P2 P1, P2} -R -CO-R ^{P1, P2} -R -CO-OR ^{P1, P2} -R -O-CO-R ^P1, - R ^P2 -OH, -R ^P2- CN, or -R ^P2- COOH (hereinafter, these substituents are collectively referred to as " Ra ⁰⁵ "

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. 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. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, aliphatic cyclic saturated hydrocarbon group and aromatic hydrocarbon group of R ^P1 and R ^P2 may be substituted with a fluorine atom. The aliphatic cyclic hydrocarbon group may have one or more of the above substituents singly or may have one or more of the above plurality of substituents.

Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and a decyl group.

Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, cyclododecyl group Monocyclic aliphatic saturated hydrocarbon group such as bicyclo [2.2.2] octanyl, tricyclo [5.2.1.02,6] decanyl, tricyclo [3.3.1.13,7] decanyl, tetracyclo [6.2.1.13] 6.02,7] dodecanyl group, adamantyl group, and other polycyclic aliphatic saturated hydrocarbon groups.

Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene and the like.

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

· Tertiary alkyl ester type acid dissociable group:

Among the polar groups, examples of the acid dissociable groups for protecting the carboxyl group include acid dissociable groups represented by the following general formula (a1-r-2).

 Further, among the acid dissociable groups represented by the following formula (a1-r-2), those composed of an alkyl group are sometimes referred to as " tertiary alkyl ester-type acid dissociable groups " for convenience.

[Chemical Formula 4]

Wherein Ra ' ⁴ to Ra' ⁶ are each a hydrocarbon group, and Ra ' ⁵ and Ra' ⁶ may combine with each other to form a ring.

Examples of the hydrocarbon group of Ra ' ⁴ include a linear or branched alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group.

Ra ^'4 group is a linear or a hydrocarbon group, a cyclic branched in the Ra' are the same and ^3.

The chain type or cyclic alkenyl group in Ra ' ⁴ is preferably an alkenyl group having 2 to 10 carbon atoms.

Examples of the hydrocarbon group for Ra ' ⁵ and Ra' ^{6 include} the same groups as those for Ra ' ³ .

Ra ^'5 and Ra' ⁶ in this case to bond to one another to form a ring, to a group, represented by formula (a1-r2-1) a group, represented by formula (a1-r2-2) formula (a1 -R2-3).

On the other hand, when Ra ' ⁴ to Ra' ⁶ are not bonded to each other and are independent hydrocarbon groups, there may be mentioned groups represented by the following general formula (a1-r2-4).

[Chemical Formula 5]

[Wherein, Ra ^'10 is an alkyl group, Ra of 1 to 10 carbon atoms, ¹¹ represents a group forming an aliphatic cyclic group together with the carbon atom a ¹⁰ Ra' combined. Ya is a carbon atom, and Xa is a group forming a bivalent cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of the cyclic hydrocarbon group may be substituted. Ra ⁰¹ to Ra ⁰³ each independently represent a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group and aliphatic cyclic saturated hydrocarbon group may be substituted. Two or more of Ra ⁰¹ to Ra ⁰³ may combine with each other to form a cyclic structure. Yaa is a carbon atom, and Xaa is a group forming an aliphatic cyclic group together with Yaa. Ra ⁰⁴ is an aromatic hydrocarbon group which may have a substituent. Ra ^'12 to Ra' ¹⁴ each independently represent a hydrocarbon group. * Indicates a combined hand (hereinafter, the same in this specification).

Equation (a1-r2-1) of, groups exemplified as the "Ra in the alkyl group is formulas (a1-r-1) of 1 to 10 carbon atoms in the ^{10 '3} linear or branched alkyl group of Ra desirable. Ra ^'10 is preferably an alkyl group having 1 to 5 carbon atoms.

Equation (a1-r2-1) of, Ra 'is Ra ^11' to ¹⁰ aliphatic cyclic group formed together with the carbon atoms bonded to the formula (a1-r-1) Ra '3 sentence of monocyclic or polycyclic in The group exemplified as a group-derived aliphatic hydrocarbon group is preferable.

In the formula (a1-r2-2), the bivalent cyclic hydrocarbon group formed by Xa together with Ya is preferably a cyclic monovalent hydrocarbon group in Ra ' ³ in the formula (a1-r-1) An aliphatic hydrocarbon group, an aromatic hydrocarbon group) having one or more hydrogen atoms removed therefrom.

The bivalent cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. The substituent may be the same as the substituent which the cyclic hydrocarbon group of Ra < ³ > may have.

Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra ⁰¹ to Ra ⁰³ in the formula (a1-r2-2) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, Hexyl group, heptyl group, octyl group, decyl group and the like.

Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra ⁰¹ to Ra ⁰³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclohexyl group Monocyclic aliphatic saturated hydrocarbon group such as cyclopentyl, cyclopentyl, cyclopentyl, cyclopentyl, cyclopentyl, cyclopentyl, cyclopentyl, cyclopentyl, And polycyclic aliphatic saturated hydrocarbon groups such as methyl, ethyl, n-butyl, tetracyclo [6.2.1.13,6.02,7] dodecanyl and adamantyl groups.

Ra ⁰¹ to Ra ⁰³ are preferably a hydrogen atom or a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms from the viewpoint of ease of synthesis of the monomer compound for deriving the structural unit (a1), among which hydrogen atoms , A methyl group and an ethyl group are more preferable, and a hydrogen atom is particularly preferable.

Examples of the substituent of the chain saturated hydrocarbon group or aliphatic cyclic saturated hydrocarbon group represented by Ra ⁰¹ to Ra ⁰³ include the same groups as Ra ⁰⁵ described above.

Examples of the group containing a carbon-carbon double bond generated by bonding two or more of Ra ⁰¹ to Ra ⁰³ together to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methyl A cyclohexenyl group, a cyclohexenyl group, a cyclopentylidenethenyl group, a cyclohexylidenethenyl group and the like. Among them, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylidenetrienyl group are preferable from the viewpoint of ease of synthesis of the monomer compound for deriving the structural unit (a1).

In the formula (a1-r2-3), the aliphatic cyclic group formed by Xaa together with Yaa is preferably a monocyclic group of Ra ' ^{3 in} the formula (a1-r-1) or a group exemplified as an aliphatic hydrocarbon group of a polycyclic group desirable.

In the formula (a1-r2-3), examples of the aromatic hydrocarbon group for Ra ⁰⁴ include groups obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among them, Ra ⁰⁴ is preferably a group obtained by removing one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group obtained by removing one or more hydrogen atoms from benzene, naphthalene, anthracene or phenanthrene, A group obtained by removing one or more hydrogen atoms from naphthalene or anthracene is more preferable and a group obtained by removing one or more hydrogen atoms from benzene or naphthalene is particularly preferable and a group in which one or more hydrogen atoms are removed from benzene is most preferable.

When Ra ⁰⁴ in the formula (a1-r2-3) is a naphthyl group, the bonding position at which Yaa in the formula (a1-r2-3) is bonded may be either 1 position or 2 positions of the naphthyl group .

Wherein when Ra ⁰⁴ is an anthryl group, the bonding position, which Yaa is bonded in the formula (a1-r2-3) is not 1-position of casting reel group, a 2-position or 9-position of the (a1-r2-3) Either way.

Examples of the substituent which Ra ⁰⁴ of formula (a1-r2-3) may have include a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom (fluorine, chlorine, An alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), and an alkyloxycarbonyl group.

Equation (a1-r2-4) of, Ra ', and Ra ^{12' 14} Ra is ³ 'of the each independently preferably an alkyl group of 1 to 10 carbon atoms, and the alkyl group has the formula (a1-r-1) Is more preferably a straight chain or branched alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group.

Equation (a1-r2-4) of, Ra 'is ^13, formula (a1-r-1) of the Ra in the' a linear or branched alkyl group, a monocyclic or polycyclic sentence of the example as a hydrocarbon group of ³ Is preferably an aliphatic hydrocarbon group. Among them, it is more preferable to be a group exemplified as a monocyclic group of Ra ' ³ or an aliphatic hydrocarbon group of a polycyclic group.

Specific examples of the group represented by the formula (a1-r2-1) are shown below.

[Chemical Formula 6]

(7)

Specific examples of the groups represented by the above formula (a1-r2-2) are shown below.

[Chemical Formula 8]

[Chemical Formula 9]

[Chemical formula 10]

(11)

Specific examples of the groups represented by the above formula (a1-r2-3) are shown below.

[Chemical Formula 12]

Specific examples of the group represented by the formula (a1-r2-4) are shown below.

[Chemical Formula 13]

· Tertiary alkyloxycarbonyl acid dissociable group:

As the acid dissociable group for protecting the hydroxyl group in the polar group, for example, an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as "tertiary alkyloxycarbonyl acid dissociable group" There are cases).

[Chemical Formula 14]

Wherein Ra ' ⁷ to Ra' ⁹ each represent an alkyl group.

In the formula (a1-r-3), Ra ' ⁷ to Ra' ⁹ are each preferably an alkyl group having 1 to 5 carbon atoms, more preferably 1 to 3.

 The total number of carbon atoms in each alkyl group is preferably from 3 to 7, more preferably from 3 to 5, and most preferably from 3 to 4.

Examples of the structural unit (a1) include a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent, a structural unit derived from acrylamide, a structure derived from a hydroxystyrene or a hydroxystyrene derivative , At least a part of the hydrogen atoms in the hydroxyl group of the unit is protected by a substituent containing the acid-decomposable group, a hydrogen atom in the -C (= O) -OH of the constituent unit derived from vinylbenzoic acid or vinylbenzoic acid derivative And structural units in which at least a part of the atoms are protected by a substituent including the acid-decomposable group.

As the structural unit (a1), a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent is preferable.

Specific examples of such a structural unit (a1) include a structural unit represented by the following general formula (a1-1) or (a1-2).

[Chemical Formula 15]

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond, n _a1 is 0 to 2, and Ra ¹ is an acid dissociable group represented by the formula (a1-r-1) or (a1-r-2). Ra ¹ is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3). Wa ¹ is an n _a2 +1 valent hydrocarbon group, n _a2 is 1 to 3,

In the formula (a1-1), the alkyl group having 1 to 5 carbon atoms for R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, An n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms is substituted with a halogen atom. The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable.

As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable for industrial availability.

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

The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is preferably saturated.

Specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure.

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -] and a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

Aliphatic hydrocarbon group of the branched, with preferably an alkylene group of branched, and _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include alicyclic hydrocarbon groups (groups in which two hydrogen atoms have been removed from the aliphatic hydrocarbon ring), groups in which alicyclic hydrocarbon groups are bonded to the ends of a linear or branched aliphatic hydrocarbon group , And groups in which an alicyclic hydrocarbon group is introduced in the midst of a linear or branched aliphatic hydrocarbon group. The linear or branched aliphatic hydrocarbon group may be the same as the above-mentioned linear aliphatic hydrocarbon group or branched-chain aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like. The polycyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group as a divalent hydrocarbon group in Va ¹ is a hydrocarbon group having an aromatic ring.

Such an aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. Provided that the number of carbon atoms does not include the number of carbon atoms in the substituent.

Specific examples of the aromatic ring of the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene and phenanthrene; aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom And the like. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom.

Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring (arylene group), one of the hydrogen atoms of the group (aryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring, An aryl group in the aryl group of an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, ), And the like. The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the formula (a1-1), Ra ¹ is an acid-dissociable group represented by the formula (a1-r-1) or (a1-r-2). Of these, Ra roneun ^1, the acid-dissociable group shown in that it can more easily increase the characteristics (sensitivity, shape, etc.) in a lithographic by electron beam or EUV, by the formula (a1-r-2) are preferred.

Among the acid dissociable groups represented by the formula (a1-r-2), the group represented by the general formula (a1-r2-1), the group represented by the general formula (a1- (A1-r2-3) and a group represented by the general formula (a1-r2-3) are preferable, and a group represented by the general formula desirable.

In the formula (a1-2), the hydrocarbon group of n _a2 +1 valency in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, and it may be saturated or unsaturated, and usually it is preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a combination of a linear or branched aliphatic hydrocarbon group and a ring-containing aliphatic hydrocarbon group One can say.

The above-mentioned n _a2 + 1 is preferably 2 to 4, more preferably 2 or 3.

Specific examples of the structural unit represented by the formula (a1-1) are shown below. In the following formulas, R ^{? Represents} a hydrogen atom, a methyl group or a trifluoromethyl group.

[Chemical Formula 16]

[Chemical Formula 17]

[Chemical Formula 18]

[Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 21]

[Chemical Formula 22]

(23)

≪ EMI ID =

(25)

(26)

Specific examples of the structural unit represented by the formula (a1-2) are shown below.

(27)

The constituent unit (a1) of the component (A1) may be one type or two or more types.

Roneun structural unit (a1), and in that it can more easily increase the characteristics (sensitivity, shape, etc.) in a lithographic by electron beam or EUV, than the structural unit represented by the above formula (a1-1) preferably, the Ra ¹ a more preferred case of the formula (a1-r-2) and acid-dissociable group represented by, Ra ¹ is a group represented by the group represented by general formula (a1-r2-3) represented by the above general formula (a1-r2-2) Is particularly preferable.

(A1) in the component (A1) is preferably from 5 to 60 mol%, more preferably from 10 to 55 mol%, and still more preferably from 20 to 50 mol% based on the total amount of all the constituent units constituting the component (A1) Mol% is more preferable.

By setting the ratio of the constituent unit (a1) to the lower limit value or more, a resist pattern can be easily obtained, and lithography characteristics such as sensitivity, resolution, roughness improvement or EL margin can be improved. In addition, by keeping the value below the upper limit value, balance with other constituent units can be obtained.

&Quot; Structural unit (a2) "

The structural unit (a2) is a structural unit (excluding the structural unit (a1)) containing a lactone-containing cyclic group, -SO ₂ -containing cyclic group or carbonate-containing cyclic group.

The lactone-containing cyclic group, -SO ₂ -containing cyclic group or carbonate-containing cyclic group of the constituent unit (a2) is preferably a cyclic group which is effective in improving the adhesion of the resist film to the substrate will be. By having the structural unit (a2), the solubility of the resist film in an alkali developer becomes high during the alkali development process.

The "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -O-C (═O) - in the cyclic backbone. When a lactone ring is counted as the first ring, only a lactone ring is referred to as a monocyclic ring, and when it has another ring structure, it is referred to as a polycyclic ring regardless of its structure. The lactone-containing cyclic group may be monocyclic or polycyclic.

The lactone-containing cyclic group in the structural unit (a2) is not particularly limited, and any cyclic group can be used. Specifically, the groups represented by the following general formulas (a2-r-1) to (a2-r-7) are exemplified.

(28)

[Wherein, Ra ^'21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR ", -OC (= O ) R", hydroxy group or cyano group; R " Is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group; An alkylene group having 1 to 5 carbon atoms, an oxygen atom or a sulfur atom, n 'is an integer of 0 to 2, and m' is 0 or 1.

In the general formula (a2-r-1) ~ (a2-r-7), the alkyl group in Ra ^'21 is an alkyl group having 1 to 6 carbon atoms are preferred. The alkyl group is preferably a linear or branched chain. Specific examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl and hexyl. Among them, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.

Ra 'The alkoxy group in ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably a linear or branched chain. Specifically, there may be mentioned a group which is an alkyl group and an oxygen atom (-O-) exemplified as the alkyl group in the above-mentioned Ra ^'21 connection.

Ra 'is a halogen atom in the ^21, and a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom is preferable.

Ra 'with a halogenated alkyl group in the ^21, wherein Ra' may be a group in which some or all of the hydrogen atoms of the alkyl group in ²¹ with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

In R '''s,-COOR''and -OC (= O) R''inRa' ²¹ , R '' is a hydrogen atom, an alkyl group, a lactone containing cyclic group, a carbonate containing cyclic group or a -SO ₂ -containing cyclic group.

The alkyl group in R "may be any of linear, branched, and cyclic, and preferably has 1 to 15 carbon atoms.

When R "is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, particularly preferably a methyl group or an ethyl group.

When R "is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, there may be mentioned a group obtained by removing one or more hydrogen atoms from a monocycloalkane which may be substituted with a fluorine atom or a fluorinated alkyl group and which may not be substituted, and a group derived from a polycycloalkane such as a bicycloalkane, tricycloalkane or tetracycloalkane A group in which one or more hydrogen atoms have been removed, and the like. More specifically, there may be mentioned groups obtained by removing one or more hydrogen atoms from a monocycloalkane such as cyclopentane, cyclohexane and the like; a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane And a group obtained by removing one or more hydrogen atoms from the hydrogen atom.

The lactone-containing cyclic group in R "includes the same groups as those represented by the general formulas (a2-r-1) to (a2-r-7).

The carbonate-containing cyclic group in R "is the same as the carbonate-containing cyclic group described later, and concretely includes the groups represented by the general formulas (ax3-r-1) to (ax3-r-3).

R "-SO ₂ of the-containing cyclic group, which will be described later -SO ₂ - containing cyclic group with the same and, specifically, each by the formula (a5-r-1) ~ (a5-r-4) And the like.

Ra 'hydroxy group in ²¹ is preferably a carbon number of 1 to 6, and specifically, the Ra' One or more of the hydrogen atoms of the alkyl group in ²¹ may be a substituted by a hydroxyl group.

Examples of the alkylene group having 1 to 5 carbon atoms in A "in the general formulas (a2-r-2), (a2-r-3) and (a2- , And preferred examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which -O- or -S- is interposed between the terminal or carbon atom of the alkylene group, and examples thereof include -O -CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ - and the like. A "is preferably an alkylene group of 1 to 5 carbon atoms or -O-, more preferably an alkylene group of 1 to 5 carbon atoms, and most preferably a methylene group.

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

[Chemical Formula 29]

(30)

The "-SO ₂ -containing cyclic group" refers to a cyclic group containing a ring containing -SO ₂ - in the cyclic skeleton, and specifically, the sulfur atom (S) in -SO ₂ - Is a cyclic group that forms part of the ring skeleton of < RTI ID = 0.0 > A ring containing -SO ₂ - in the ring skeleton is counted as the first ring, and when the ring is only a ring, it is called a monocyclic ring, and when it has another ring structure, it is called a ring ring regardless of its structure. The -SO ₂ -containing cyclic group may be monocyclic or polycyclic.

-SO ₂ - containing cyclic group are, in particular, those in the ring skeleton -O-SO ₂ - sultone (sultone) of the -OS- of forms part of the ring backbone-cyclic group containing, i.e. -O-SO ₂ And is preferably a cyclic group containing a ring.

Specific examples of the -SO ₂ -containing cyclic group include the groups represented by the following general formulas (a5-r-1) to (a5-r-4)

(31)

R < ⁵¹ > each independently represents 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; Is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group; A "is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, Sulfur atom, and n 'is an integer of 0 to 2.]

(A2-r-2), (a2-r-3), (a2-r-5) Quot; A "in FIG.

(A2-r-1) to (a2-r-1) in the above Ra ^'51 are each an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR " -r-7) it can be given in the same as those exemplified in the description of the Ra ^'21.

Specific examples of the groups represented by the general formulas (a5-r-1) to (a5-r-4) are described below. "Ac" in the formula represents an acetyl group.

(32)

(33)

(34)

The "carbonate-containing cyclic group" means a cyclic group containing a ring (carbonate ring) containing -O-C (═O) -O- in the cyclic backbone. When the carbonate ring is counted as the first ring, only the carbon ring is monocyclic, and when it has another ring structure, it is called the polycyclic ring regardless of its structure. The carbonate-containing cyclic group may be monocyclic or polycyclic.

The cyclic group containing a carbonate ring is not particularly limited and any cyclic group can be used. Specific examples thereof include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

(35)

[Wherein, Ra ^'x31 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR ", -OC (= O ) R", hydroxy group or cyano group; R " Is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group; A "is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, Sulfur atom, p 'is an integer of 0 to 3, and q' is 0 or 1.]

Among the above-mentioned general formulas (ax3-r-2) to (ax3-r-3), A '' represents a group represented by the general formulas (a2- Quot; A "in FIG.

(A2-r-1) to (a2-r-1) in the above Ra ^'31 are each an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR " -r-7) it can be given in the same as those exemplified in the description of the Ra ^'21.

Specific examples of the groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are described below.

(36)

As the structural unit (a2), a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent is preferable.

Such a structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

(37)

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya ²¹ is a single bond or a divalent linking group. La ²¹ represents -O-, -COO-, -CON (R ') -, -OCO-, -CONHCO- or -CONHCS-, and R' represents a hydrogen atom or a methyl group. However, when La ²¹ is -O-, Ya ²¹ is not -CO-. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group.]

In the formula (a2-1), R is the same as described above.

The divalent linking group of Ya ²¹ is not particularly limited, but a bivalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like are suitable.

A bivalent hydrocarbon group which may have a substituent;

When Ya ²¹ is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

Aliphatic hydrocarbon groups in Ya ²¹

The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is preferably saturated.

Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure.

... .Lectric or branched aliphatic hydrocarbon groups

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -] and a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

The branch-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

Aliphatic hydrocarbon group of the branched, with preferably an alkylene group of branched, and _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

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

... an aliphatic hydrocarbon group containing a ring in the structure

Examples of the aliphatic hydrocarbon group containing a ring in the structure include a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which may contain a substituent group containing a hetero atom in the ring structure, A group in which a hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is introduced in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same ones as described above.

The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The cyclic aliphatic hydrocarbon group may be either a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl 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 isopropoxy group, a n-butoxy group or a tert- , Ethoxy group is most preferable.

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 a part or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom.

The cyclic aliphatic hydrocarbon group may be substituted with a substituent group in which a part of carbon atoms constituting the cyclic structure includes a hetero atom. The substituent containing the heteroatom is preferably -O-, -C (= O) -O-, -S-, -S (= O) _2- or -S (= O) ₂ -O- .

The aromatic hydrocarbon group in Ya ²¹

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 < [pi] > electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12. Provided that the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include groups obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group), aromatic compounds containing two or more aromatic rings (for example, biphenyl, A group in which one hydrogen atom of a group (aryl group or heteroaryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group ( For example, an aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, Removed), and the like. The number of carbon atoms of the alkylene group bonded to the aryl group or the heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the aromatic hydrocarbon group, the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

Examples of the alkoxy group, the halogen atom and the halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

A divalent linking group containing a hetero atom:

When Y ^{< a} > is a divalent linking group containing a heteroatom, preferable examples of the linking group include -O-, -C (= O) -O-, -C (= O) -, -OC -, -C (= O) -NH-, -NH-, -NH-C (= NH) - (H may be substituted with a substituent such as an alkyl group or an acyl group) = O) ₂ -, -S (= O) ₂ -O-, a group represented by the formula -Y ²¹ -OY ²² -, -Y ²¹ -O-, -Y ²¹ -C (= O) ^{= O) -OY 21 -, -} [Y 21 -C (= O) -O] m "-Y 22 -, -Y 21 -OC (= O) -Y 22 - or -Y ²¹ -S (= O ) ₂ -OY ²² - [wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m "is an integer of 0 to 3] And the like.

The divalent linking group containing the hetero atom may be -C (= O) -NH-, -C (= O) -NH-C (= O) -, -NH-, -NH-C , The H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.

Formula ^{-Y 21 -OY 22 -, -Y 21} -O-, -Y 21 -C (= O) -O-, -C (= O) -OY 21 -, - [Y 21 -C (= O -O] _{m "} -Y ²² -, -Y ²¹ -OC (═O) -Y ²² - or -Y ²¹ -S (═O) ₂ -OY ²² -, Y ²¹ and Y ²² are each independently And is a divalent hydrocarbon group which may have a substituent. The divalent hydrocarbon group may be the same as the divalent hydrocarbon group which may have a substituent (s) exemplified in the description of the divalent linking group.

As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is more preferable, and a methylene group or an ethylene group is particularly preferable.

Y ²² is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.

In the group represented by the formula - [Y ²¹ -C (═O) -O] _{m "} -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1 , And 1 is particularly preferable. That is, the group represented by the formula - [Y ²¹ -C (═O) -O] _{m "} -Y ²² - is particularly preferably a group represented by the formula -Y ²¹ -C (═O) -OY ²² -. Among them, a group represented by the formula - (CH ₂ ) _{a '} -C (═O) -O- (CH ₂ ) _b' - is preferable. In the formula, a 'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1. b 'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.

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

In the formula (a2-1), Ra ²¹ is a lactone-containing cyclic group, -SO ₂ - containing cyclic group or a carbonate-containing cyclic group.

The lactone-containing cyclic group, -SO ₂ -containing cyclic group and carbonate cyclic group in Ra ²¹ each represent a group represented by the aforementioned general formulas (a2-r-1) to (a2-r-7) Groups represented by formulas (a5-r-1) to (a5-r-4) and groups represented by formulas (ax3-r-1) to (ax3-r-3), respectively.

Among them, the lactone-containing cyclic group or -SO ₂ - containing cyclic group is preferred, and the formula (a2-r-1), (a2-r-2), (a2-r-6) or (a5-r -1) is more preferable. (R-lc-2-1) to (r-lc-2-18), (r-lc-1-7) 6-1), (r-sl-1-1) and (r-sl-1-18), respectively.

The constituent unit (a2) of the component (A1) may be one type or two or more kinds.

When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 80 mol%, more preferably 10 to 20 mol%, based on the total of all structural units constituting the component (A1) , More preferably 70 mol%, still more preferably 10 mol% to 65 mol%, and particularly preferably 10 mol% to 60 mol%.

When the ratio of the constituent unit (a2) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a2) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units can be obtained, The lithography characteristics and the pattern shape are improved.

&Quot; Structural unit (a3) "

The structural unit (a3) is a structural unit (excluding the structural unit (a1) or structural unit (a2)) containing a polar group-containing aliphatic hydrocarbon group.

 The component (A1) has the structural unit (a3), so that the hydrophilicity of the component (A) is enhanced and contributes to improvement of the resolution.

Examples of the polar group include a hydroxyl group, a cyano group, a carboxyl group, a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom, and a hydroxyl group is particularly preferable.

Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) or a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be monocyclic or polycyclic. For example, the resin for a resist composition for an ArF excimer laser may be appropriately selected from among many proposed ones. The cyclic group is preferably a polycyclic group and more preferably 7 to 30 carbon atoms.

Among them, a structural unit derived from an acrylate ester containing a hydroxyl group, a cyano group, a carboxyl group, or an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from a bicycloalkane, a tricycloalkane, a tetracycloalkane or the like. Specific examples thereof include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isoborane, tricyclodecane and tetracyclododecane. Among these polycyclic groups, groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane are industrially preferable.

The constituent unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group.

The constituent unit (a3) is preferably a constituent unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent, and a polar group-containing aliphatic hydrocarbon group.

When the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms, the structural unit (a3) is preferably a structural unit derived from a hydroxyethyl ester of acrylic acid, When the hydrocarbon group is a polycyclic group, preferred examples include a constituent unit represented by the following formula (a3-1), a constituent unit represented by the formula (a3-2), and a constituent unit represented by the formula (a3-3)

(38)

Wherein R is as defined above, j is an integer of 1 to 3, k is an integer of 1 to 3, t 'is an integer of 1 to 3, 1 is an integer of 1 to 5, s is It is an integer from 1 to 3.]

In formula (a3-1), j is preferably 1 or 2, more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3-position and the 5-position of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.

j is preferably 1, and it is particularly preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.

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

In formula (a3-3), t 'is preferably 1. l is preferably 1. s is preferably 1. These are preferably those in which a 2-norbornyl group or a 3-norbornyl group is bonded to the terminal of the carboxyl group of acrylic acid. It is preferable that the fluorinated alkyl alcohol is bonded to the 5th or 6th position of the norbornyl group.

The constituent unit (a3) of the component (A1) may be one type or two or more types.

When the component (A1) has the structural unit (a3), the proportion of the structural unit (a3) is preferably from 5 to 50 mol%, more preferably from 5 to 50 mol% based on the total structural units constituting the component (A1) , More preferably 40 mol%, and still more preferably 5 mol% to 35 mol%.

When the ratio of the constituent unit (a3) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a3) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units becomes easy.

&Quot; Structural unit (a4) "

The structural unit (a4) is a structural unit containing an acid-labile aliphatic cyclic group.

When the component (A1) has the structural unit (a4), dry etching resistance of the formed resist pattern is improved. Further, the hydrophobicity of the component (A) is increased. It is considered that the improvement of the hydrophobicity contributes to the improvement of the resolution and the shape of the resist pattern in the case of the solvent developing process in particular.

The "acid-labile cyclic group" in the constituent unit (a4) is preferably an acid labile cyclic group when the acid is generated in the resist composition by exposure (for example, when acid is generated from the component (B1) Is a cyclic group remaining in the constituent unit as it is without dissociating.

As the constituent unit (a4), for example, a constituent unit derived from an acrylate ester containing an aliphatic cyclic group having acidity is preferable. The cyclic group is used for a resin component of a resist composition such as an ArF excimer laser or a KrF excimer laser (preferably for an ArF excimer laser), and many conventionally known ones can be used.

Particularly, at least one member selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group and a norbornyl group is preferable from the viewpoint of industrial availability and the like. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

Specific examples of the structural unit (a4) include structural units represented by the following general formulas (a4-1) to (a4-7).

[Chemical Formula 39]

[Wherein R ^? Is as defined above].

The constituent unit (a4) of the component (A1) may be one type or two or more types.

When the component (A1) has the structural unit (a4), the proportion of the structural unit (a4) is preferably from 1 to 30 mol%, more preferably from 3 to 30 mol%, based on the total of all structural units constituting the component (A1) More preferably 20 mol%.

When the ratio of the constituent unit (a4) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a4) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units becomes easy.

&Quot; Structural unit (a9) "

The structural unit (a9) is a structural unit represented by the following general formula (a9-1).

(40)

Wherein R is as defined above, Ya ⁹¹ is a single bond or a divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and Ya ⁹² is a divalent linking group.

In the formula (a9-1), R is the same as described above.

As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is particularly preferable for industrial availability.

In the formula (a9-1), the divalent linking group in Ya ⁹¹ may be the same as the divalent linking group of Ya ^{21 in} the general formula (a2-1) described above. Ya ⁹¹ is preferably a single bond.

In the formula (a9-1), the divalent linking group in Ya ⁹² may be the same as the divalent linking group of Ya ^{21 in} the general formula (a2-1) described above.

As the divalent hydrocarbon group which may have a substituent in the divalent linkage group of Ya ⁹² , a linear or branched aliphatic hydrocarbon group is preferable.

The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -] and a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, further preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. Aliphatic hydrocarbon group of the branched, with preferably an alkylene group of branched, and _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

In the bivalent linking group in Ya ⁹² , examples of the divalent linking group which may have a hetero atom include -O-, -C (= O) -O-, -C (= O) -, -OC -O-, -C (= O) -NH-, -NH-, -NH-C (= NH) - (H may be substituted with a substituent such as an alkyl group or an acyl group) _{-, -S (= O) 2} -, -S (= O) 2 -O-, -C (= S) -, the formula ^{-Y 21 -OY 22 -, -Y 21} -O-, -Y 21 -C (= O) -O-, -C (= O) -OY 21, [Y 21 -C (= O) -O] m '-Y 22 - or -Y ²¹ -OC (= O) -Y ²² -, wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom and m 'is an integer of 0 to 3, etc. have. Among them, -C (= O) - and -C (= S) - are preferable.

In the formula (a9-1), examples of the hydrocarbon group for R ⁹¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.

The alkyl group for R ⁹¹ preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and may be linear or branched. Specifically, methyl group, ethyl group, propyl group, butyl group, hexyl group, and octyl group are preferable.

The monovalent alicyclic hydrocarbon group for R ⁹¹ preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing at least one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group in which at least one hydrogen atom is removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, and the like.

The aryl group in R ⁹¹ preferably has 6 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably a phenyl group.

To an aralkyl group in R ⁹¹ is an "aryl group in R ^91," an aralkyl group is bonded alkylene group and the group having 1 to 8 carbon atoms is preferable, according to an alkylene group wherein the "R ⁹¹ having 1 to 6 carbon atoms Is more preferably an aralkyl group bonded with an alkylene group having 1 to 4 carbon atoms and the above-mentioned " aryl group in R ⁹¹ ".

As the hydrocarbon group for R ⁹¹ , a part or all of the hydrogen atoms of the hydrocarbon group is preferably substituted with a fluorine atom, and it is more preferable that 30 to 100% of the hydrogen atoms of the hydrocarbon group is substituted with a fluorine atom. Among them, it is particularly preferable that all the hydrogen atoms of the alkyl group described above are perfluoroalkyl groups substituted with fluorine atoms.

The hydrocarbon group for R ⁹¹ may have a substituent. Examples of the substituent include a halogen atom, an oxo group (= O), a hydroxyl group (-OH), an amino group (-NH ₂ ), -SO ₂ -NH ₂ , and the like. In addition, a part of carbon atoms constituting the hydrocarbon group may be substituted with a substituent containing a hetero atom. The substituent group containing the heteroatom includes -O-, -NH-, -N═, -C (═O) -O-, -S-, -S (═O) _2- , -S ) _2- O-.

Examples of the hydrocarbon group having a substituent in R ⁹¹ include a lactone-containing cyclic group represented by the above general formulas (a2-r-1) to (a2-r-7).

Examples of the hydrocarbon group having a substituent in R ⁹¹ include -SO ₂ -containing cyclic groups represented by the general formulas (a5-r-1) to (a5-r-4), substituted aryl groups , A monovalent heterocyclic group, and the like.

(41)

Among the structural units (a9), structural units represented by the following general formula (a9-1-1) are preferable.

(42)

Wherein R is as defined above, Ya ⁹¹ is a single bond or a divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and R ⁹² is an oxygen atom or a sulfur atom.

The description of Ya ⁹¹ , R ⁹¹ , and R in the general formula (a9-1-1) is the same as described above. R ⁹² is an oxygen atom or a sulfur atom.

Specific examples of the structural unit represented by the formula (a9-1) or the general formula (a9-1-1) are shown below. In the formula, R ^{? Represents} a hydrogen atom, a methyl group or a trifluoromethyl group.

(43)

(44)

[Chemical Formula 45]

The structural unit (a9) contained in the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (a9), the proportion of the structural unit (a9) is preferably 1 to 40 mol%, more preferably 3 to 10 mol%, based on the total of all structural units constituting the component (A1) , More preferably 30 mol%, and particularly preferably 10 mol% to 30 mol%.

When the ratio of the constituent unit (a9) is set to a lower limit value or more, lithographic characteristics such as development characteristics and EL margin are improved. When the proportion is less than the upper limit value, balance with other constituent units is easy.

«Constituent unit (st)»

The structural unit (st) is a structural unit derived from hydroxystyrene or styrene.

Examples of the preferable structural unit (st) include a structural unit (st1) represented by the following general formula (I) and a structural unit (st2) represented by the following general formula (II).

(46)

Wherein R ^st represents a hydrogen atom or a methyl group. m ₀₁ represents an integer of 1 to 3; R ⁰¹ represents an alkyl group having 1 to 5 carbon atoms. m ₀₂ represents 0 or an integer of 1 to 3.]

In the formula (I), R ^st is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom.

m ₀₁ is an integer of 1 to 3, preferably 1.

The bonding position of the hydroxyl group in the benzene ring may be any of o-position, m-position and p-position, but m ₀₁ is 1 in view of availability and low cost, It is preferable to have a hydroxyl group. When m ₀₁ is 2 or 3, arbitrary substitution positions can be combined.

In the formula (II), R ^st is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom.

R ⁰¹ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms and is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert- Isopentyl group, neopentyl group and the like. Industrially, a methyl group or an ethyl group is preferable.

m ₀₂ is 0 or an integer of 1 to 3; Of these, m ₀₂ is preferably 0 or 1, and more preferably 0 for industrial use. When m ₀₂ is 1, the substitution position of R ^{01 in} the benzene ring may be any of o-, m- and p-, and when m ₀₂ is 2 or 3, The substitution positions can be combined.

The constituent unit (st) contained in the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (st), the proportion of the structural unit (st) is preferably from 1 to 80 mol%, more preferably from 10 to 80 mol%, based on the total of all structural units constituting the component (A1) , More preferably 75 mol%, and still more preferably 20 mol% to 70 mol%.

When the proportion of the constituent unit (st) is set to the lower limit value or more, lithographic characteristics such as development characteristics and EL margin are improved. When the proportion is less than the upper limit value, balance with other constituent units can be easily achieved.

In the resist composition of the present embodiment, the component (A) preferably comprises the polymer (A1) having the structural unit (a1).

The component (A1) contained in the resist composition may be used singly or in combination of two or more.

Preferred examples of the component (A1) include a polymer compound having a repeating structure of the structural unit (a1) and the structural unit (a2) (hereinafter also referred to as "component (A1-1)"), a structural unit (a1) st) (hereinafter also referred to as " component (A1-2) ").

Specific examples of the component (A1) include a polymer compound comprising a repeating structure of the structural unit (a1) and the structural unit (a2), a repeating structure of the structural unit (a1), the structural unit (a2) (A1) and a structural unit (st), a polymer compound comprising a repeating structure of the structural unit (a1), the structural unit (st) and the structural unit (a9), the structural unit (a1), a structural unit (a2), a structural unit (st) and a structural unit (a9).

As the component (A), it is also preferable to use a combination of the component (A1-1) and the component (A1-2).

The ratio (mass ratio) of the component (A1-1) to the component (A1-2) is preferably from 1/9 to 9/1, more preferably from 3/7 to 7/1 / 3 is more preferable, and 5/5 is more preferable.

The mass average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography (GPC)) of the component (A1) is not particularly limited, but is preferably about 1000 to 500000, more preferably about 3,000 to 50,000 .

If the Mw of the component (A1) is not more than the upper limit of the preferable range, there is sufficient solubility in a resist solvent for use as a resist. If the Mw is not less than the lower limit of the above range, The shape is good.

The dispersion degree (Mw / Mn) of the component (A1) is not particularly limited, but is preferably about 1.0 to 4.0, more preferably about 1.0 to 3.0, and particularly preferably about 1.5 to 2.5. Mn represents the number average molecular weight.

The proportion of the component (A1) in the component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, further preferably 75% by mass or more, Mass%. If the ratio is 25 mass% or more, a resist pattern having excellent lithography properties such as high sensitivity and roughness improvement is likely to be formed. Such an effect is remarkable particularly in lithography by electron beam or EUV.

(A1) Component:

The component (A1) is obtained by dissolving a monomer for deriving each constituent unit in a polymerization solvent and adding thereto, for example, azobisisobutyronitrile (AIBN), dimethyl 2,2'-azobisisobutyrate , V-601, etc.) and then polymerizing them. In addition, when a chain transfer agent such as HS-CH ₂ -CH ₂ -CH ₂ -C (CF ₃ ) ₂ -OH is used in combination during the polymerization, a -C (CF ₃ ) ₂ -OH group . As described above, a copolymer into which a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is substituted with a fluorine atom is introduced is effective for reduction of development defects and reduction of LER (line edge roughness: uneven irregularity of line side wall).

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

The content of the component (A) in the resist composition of the present embodiment may be adjusted depending on the thickness of the resist film to be formed.

≪ Component (B1) >

The resist composition of the present embodiment contains a compound (component (B1)) represented by the following general formula (b1).

(47)

^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 (provided that the aromatic ring is benzene Ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).]

&Quot; Catite part of component (B1) "

In the formula (b1), R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 And when the ring is a benzene ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings.

The aromatic ring in R ^b1 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 from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12.

Examples of R ^b1 include groups obtained by removing one or more hydrogen atoms from aromatic hydrocarbon rings such as a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, etc., and at least one hydrogen atom from a benzene ring or a naphthalene ring A group obtained by removing one or more hydrogen atoms from the benzene ring is more preferable.

R ^b10 of -SO ₂ R ^b10 is in the R ^b1 represents an alkyl group, a fluorinated alkyl group or an aryl group.

As the alkyl group for R ^b10 , an alkyl group having 1 to 10 carbon atoms is ^exemplified , and an alkyl group having 1 to 5 carbon atoms is preferable.

A fluorinated alkyl group in the R ^b10 is, some or all of the hydrogen atoms of the "alkyl group in R ^b10" of the number of substituted groups with a fluorine atom.

The aryl group for R ^b10 includes the same groups as R ^b1 .

The electron attractive group possessed by the aromatic ring in R ^b1 is preferably a fluorine atom or a trifluoromethyl group among the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 .

The aromatic ring in R ^b1 has at least one electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 , but the aromatic ring of the electron- Is not limited unless the aromatic ring in R ^b1 is a benzene ring.

The number of the electron-withdrawing groups to be bonded to the aromatic rings in R ^b1 may be one or two or more. When a plurality of the above-mentioned electron-withdrawing groups are bonded to the aromatic ring, the plural electron-withdrawing groups may be the same or different.

However, when the aromatic ring in R ^b1 is a benzene ring, the electron-withdrawing group is bonded to at least one of the meta positions of the benzene ring. The electron-withdrawing group may be bonded to both meta positions in the benzene ring. In addition to the meta position of the benzene ring, the electron-withdrawing group may be bonded to one or both of the ortho and para positions of the benzene ring.

When the aromatic ring in R ^b1 is a benzene ring bonded to the meta position of the electron-withdrawing group, the component (B1) is a benzene ring in which the electron-withdrawing group is not bonded to the meta position, It does not decompose well in the resist composition and has excellent stability over time.

When R ^b1 is an aromatic ring other than the benzene ring, the bonding position of the electron-withdrawing group to the aromatic ring may be a position adjacent to the carbon atom (1 position) to which the sulfur atom (S) in the formula (b1) It is preferable not to be a carbon atom (2 position) in view of lithography characteristics.

The aromatic ring in R ^b1 may have a substituent other than the electron-withdrawing group. Substituents other than the electron-withdrawing group include, for example, alkyl having 1 to 5 carbon atoms.

In the formula (b1), R ^b21 and R ^b22 each independently represent a group capable of having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 Represents a directional ring.

To aromatic ring in R ^b21 and R ^b22 it may be mentioned which can form a heterocyclic ring structure by, a sulfur atom (S) of each, and R ^b21, R ^b22 and the formula (b1).

The -SO ₂ R ^b20 and R ^{b22 b21} in R R ^b20 are each represents an alkyl group, a fluorinated alkyl group or an aryl group, those similar to the R and ^b10.

In the formula (b1), Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. Of these, Z is preferably a single bond.

In the formula (b1), R ^b1 and R ^b21 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula.

R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula.

The preferred cation unit of the component (B1) is a cation represented by the following formula (b1-c).

(48)

[Wherein Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond]. R ^b01 represents an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 . When there are a plurality of R ^{b01 in the} formula (b1-c), they may be mutually the same or different. R ^b02 is an alkyl group having 1 to 5 carbon atoms. When plural R ^b02 exist in the formula (b1-c), they may be mutually the same or different. n _b1 is 0 or an integer of 1 to 4; n _b3 and n _b5 are each independently 0 or an integer of 1 to 5; n _b2 is 0 or an integer of 1 to 4; n _b4 and n _b6 are each independently 0 or an integer of 1 to 5; _Wherein 0? _Nb1 + _nb2 ? 4, 0? _Nb3 + _nb4 ? 5, 0? _Nb5 + _nb6 ? 5.

In the formula (b1-c), Z is preferably a single bond among a sulfur atom, an oxygen atom, a carbonyl group or a single bond.

The electron attractive group in R ^b01 is preferably a fluorine atom or a trifluoromethyl group among the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 .

Of the alkyl groups having 1 to 5 carbon atoms, R ^b02 is preferably a methyl group or an ethyl group.

n _b1 is preferably 0 or 1.

n _b3 and n _b5 are each preferably 0, 1 or 2, and more preferably 0.

n _b2 is preferably 0 or 1, more preferably 0.

n _b4 and n _b6 are each preferably 0, 1 or 2, and more preferably 0.

Specific examples of the cation portion represented by the general formula (b1-c) are described below.

(49)

&Quot; Anion of component (B1) "

In the above formula (b1), X ^- represents a counter anion (excluding BF ₄ ^- ).

X ^- roneun, may not be appropriate in the whole not particularly limited, and known as the no moiety of the component acid generator for a resist composition.

For example, X ^{- can} be an anion represented by the following general formula (b1-a1), an anion represented by the general formula (b1-a2) or an anion represented by the general formula (b1-a3)

(50)

Wherein R ¹⁰¹ and R ¹⁰⁴ to R ¹⁰⁸ each independently represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ¹⁰¹ to V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ¹⁰¹ to L ¹⁰² each independently represent a single bond or an oxygen atom. L ¹⁰³ to L ¹⁰⁵ each independently represents a single bond, -CO- or -SO ₂ -.

Anion represented by the general formula (b1-a1)

In the formula (b1-a1), R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.

A cyclic group which may have a substituent:

The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually saturated.

The aromatic hydrocarbon group in R < ¹⁰¹ > is a hydrocarbon group having an aromatic ring. The number of carbon atoms of the aromatic hydrocarbon group is preferably from 3 to 30, more preferably from 5 to 30, still more preferably from 5 to 20, particularly preferably from 6 to 15, most preferably from 6 to 10. Provided that the number of carbon atoms does not include the number of carbon atoms in the substituent.

Specific examples of the aromatic ring of the aromatic hydrocarbon group in R ¹⁰¹ include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, aromatic heterocyclic rings in which a part of carbon atoms constituting aromatic rings thereof are substituted with a hetero atom Rings and the like. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom.

Specific examples of the aromatic hydrocarbon group for R ¹⁰¹ include a group in which one hydrogen atom is removed from the aromatic ring (aryl group: e.g., phenyl group, naphthyl group, etc.), one of the hydrogen atoms in the aromatic ring is alkylene (For example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group and the like) and the like. The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The cyclic aliphatic hydrocarbon group for R ¹⁰¹ includes an aliphatic hydrocarbon group containing a ring in its structure.

As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group , And groups in which an alicyclic hydrocarbon group is introduced in the midst of a linear or branched aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing at least one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing at least one hydrogen atom from the polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, the polycycloalkane is preferably a polycycloalkane having a polycyclic structure of a bridge ring system such as adamantane, norbornane, isoborane, tricyclodecane, tetracyclododecane, etc., a ring having a steroid skeleton And a polycycloalkane having a polycyclic structure of a condensed ring system such as a formyl group is more preferable.

Among them, the cyclic aliphatic hydrocarbon group for R ¹⁰¹ is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane, more preferably a group obtained by removing one hydrogen atom from a polycycloalkane, An adamantyl group and a norbornyl group are particularly preferable, and an adamantyl group is most preferable.

The number of carbon atoms of the linear aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group is preferably from 1 to 10, more preferably from 1 to 6, still more preferably from 1 to 4, and most preferably from 1 to 3. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -] and a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms. Aliphatic hydrocarbon group of the branched, with preferably an alkylene group of branched, and _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The cyclic hydrocarbon group in R ¹⁰¹ may include a hetero atom such as a heterocyclic ring. Specifically, a lactone-containing cyclic group represented by any one of the above-mentioned general formulas (a2-r-1) to (a2-r-7) (R-hr-1) to (r-hr-16), which are represented by the above-mentioned -SO ₂ -containing cyclic groups.

Examples of the substituent in the cyclic group of R < ¹⁰¹ > include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and a nitro group.

The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group.

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, , Ethoxy group is most preferable.

Examples of the halogen atom as a 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 a substituent include an alkyl group having 1 to 5 carbon atoms such as a group in which a part or all of hydrogen atoms such as methyl, ethyl, propyl, n-butyl and tert- have.

The carbonyl group as a substituent is a group substituting the methylene group (-CH ₂ -) constituting the cyclic hydrocarbon group.

Chain alkyl group which may have a substituent:

The chain alkyl group represented by R < ¹⁰¹ > may be either linear or branched.

The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specific examples thereof include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, , A tetradecyl group, a pentadecyl group, a hexadecyl group, an isohexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an eicosyl group, a heneicosyl group and a docosyl group.

The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples thereof include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, -Ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group.

Chain alkenyl group which may have a substituent:

The chain-like alkenyl group of R < ¹⁰¹ > may be either linear or branched, preferably has 2 to 10 carbon atoms, more preferably 2 to 5, still more preferably 2 to 4, 3 is particularly preferable. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butyryl group. Examples of the branched-chain alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group and a 2-methylpropenyl group.

As the chain-like alkenyl group, among these, a linear-chain alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain type alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, a cyclic group in the R ¹⁰¹ , .

Among them, R ¹⁰¹ is preferably a cyclic group which may have a substituent, more preferably a cyclic hydrocarbon group which may have a substituent. (A2-r-1) to (a2-r-7), a cyclic group containing a lactone represented by the general formula And -SO ₂ -containing cyclic groups represented by the general formulas (a5-r-1) to (a5-r-4) are preferable.

In the formula (b1-a1), Y ¹⁰¹ is a divalent linking group containing a single bond or an oxygen atom.

If the Y ¹⁰¹ 2-valent connecting group containing an oxygen atom, and Y is ^101, it may contain an atom other than an oxygen atom. Examples of the atom other than the oxygen atom include a carbon atom, a hydrogen atom, a sulfur atom, and a nitrogen atom.

Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: -O-), an ester bond (-C (= O) -O-), an oxycarbonyl group (-OC Hydrocarbon group-containing oxygen atom-containing linking groups such as an amide bond (-C (= O) -NH-), a carbonyl group (-C (= O) -) ; A combination of a non-hydrocarbon-based oxygen atom-containing linking group and an alkylene group; and the like. This combination may also be connected with a sulfonyl group (-SO ₂ -). Examples of the divalent linking group containing such an oxygen atom include linking groups represented by the following general formulas (y-al-1) to (y-al-7), respectively.

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Wherein V ' ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.

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

The alkylene group in V ' ¹⁰¹ and V' ¹⁰² may be a linear alkylene group or a branched chain alkylene group, preferably a linear alkylene group.

V as an alkylene group in the ^"101 and V" ^102, specifically, a methylene group _{[-CH 2 -]; - 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 ) -, and -C (CH ₂ CH ₃ ) ₂ -; an ethylene group _{[-CH 2 CH 2 -];} - CH (CH 3) CH 2 -, -CH (CH 3) CH (CH 3) -, -C (CH 3) 2 CH 2 -, -CH (CH 2 CH ₃₎ CH ₂ - alkyl group such as ethylene; trimethylene group (n- propylene _{group) [-CH 2 CH 2 CH 2} -]; - CH (CH 3) CH 2 CH 2 -, -CH 2 CH (CH ₃₎ CH ₂ - alkyl trimethylene group and the like; a tetramethylene group _{[-CH 2 CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 CH 2 -, -CH 2 CH (CH 3) An alkyltetramethylene group such as CH ₂ CH ₂ -, a pentamethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -] and the like.

A part of the methylene groups in the alkylene group in V ' ¹⁰¹ or V' ¹⁰² may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is obtained by further removing one hydrogen atom from a cyclic aliphatic hydrocarbon group (monocyclic aliphatic hydrocarbon group, polycyclic aliphatic hydrocarbon group) of Ra ' ³ in the formula (a1-r-1) A divalent group is preferable, and a cyclohexylene group, a 1,5-adamantylene group or a 2,6-adamantylene group is more preferable.

Y ¹⁰¹ is preferably a divalent linking group containing an ester linkage or a divalent linking group containing an ether linkage, more preferably a linking group represented by the above formulas (y-al-1) to (y-al-5) Do.

In the formula (b1-a1), V ¹⁰¹ is a single bond, an alkylene group or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group in V ¹⁰¹ preferably have 1 to 4 carbon atoms. A fluorinated alkylene group in the V ¹⁰¹ is, a part or all of the hydrogen atoms of the alkylene group of the ¹⁰¹ V may be substituted with a fluorine atom. Among them, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In the formula (b1-a1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, more preferably a fluorine atom.

Specific examples of the anion moiety represented by the formula (b1-a1) include, for example, when Y ¹⁰¹ is a single bond, a fluorinated Alkyl sulfonate anion, and when Y ¹⁰¹ is a divalent linking group containing an oxygen atom, an anion represented by any one of the following formulas (an-1) to (an-3) is exemplified.

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Wherein R " ¹⁰¹ represents an aliphatic cyclic group which may have a substituent, a group respectively represented by the above formulas (r-hr-1) to (r-hr-6), or a chain alkyl group and; r ^"102 is an aliphatic cyclic group which may have a substituent, the formula (a2-r-1) ~ lactone-containing cyclic group represents respectively (a2-r-7), or the formula (a5-r -SO ₂ -containing cyclic group represented by the formula (a-1) to (a5-r-4), R " ¹⁰³ represents an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, Is independently an integer of 0 to 3, q "is independently an integer of 1 to 20, t" is an integer of 1 to 3, and n " 1.]

R ^"101, R" ¹ and R ⁰² "aliphatic cyclic group which may have a substituent group ¹⁰³ is preferably a group exemplified as the aliphatic hydrocarbon group in the above R of the annular ^101. Examples of the substituent include the same substituent as the substituent which may be substituted with the cyclic aliphatic hydrocarbon group in R ¹⁰¹ .

The aromatic cyclic group which may have a substituent in R " ¹⁰³ is preferably a group exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group for R < ^{101 &} gt ;. Examples of the substituent include the same substituent as the substituent that the aromatic hydrocarbon group in R ¹⁰¹ may be substituted.

The chain alkyl group which may have a substituent in R " ¹⁰¹ is preferably a group exemplified as a chain alkyl group in R < ^{101 &} gt ;. The chain type alkenyl group which may have a substituent in R " ¹⁰³ is preferably a group exemplified as a chain type alkenyl group in R < ^{101 &} gt ;.

Anion represented by the general formula (b1-a2)

In formula (b1-a2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, Include the same ones as R ¹⁰¹ in the formula (b1-a1), respectively. However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.

R ¹⁰⁴ and R ¹⁰⁵ are preferably a chain-like alkyl group which may have a substituent, more preferably a linear or branched alkyl group, or a linear or branched chain fluorinated alkyl group.

The number of carbon atoms of the chain-like alkyl group is preferably from 1 to 10, more preferably from 1 to 7, and still more preferably from 1 to 3, carbon atoms. The number of carbon atoms of the chain-like alkyl group represented by R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible within the above range of the number of carbon atoms and solubility in a resist solvent. In the chain type alkyl groups represented by R ¹⁰⁴ and R ^105, the higher the number of hydrogen atoms substituted with fluorine atoms is, the stronger the strength of the acid, and the higher the transparency to the high energy light of 200 nm or less and the electron beam is improved desirable. The ratio of the fluorine atoms in the chain alkyl group, that is, the fluoride group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably, the perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms to be.

In the formula (b1-a2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group, and the same groups as those of V ¹⁰¹ in the formula (b1-a1) may be mentioned.

In the formula (b1-a2), L ¹⁰¹ and L ¹⁰² each independently represent a single bond or an oxygen atom.

Anion represented by the general formula (b1-a3)

In the formula (b1-a3), each of R ¹⁰⁶ to R ¹⁰⁸ independently represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent or a chain-like alkenyl group which may have a substituent, Include the same ones as R ¹⁰¹ in the formula (b1-a1), respectively.

In the formula (b1-a3), L ¹⁰³ to L ¹⁰⁵ each independently represent a single bond, -CO- or -SO ₂ -.

In the above formula (b1), X < ^- > may be halogen anion. Examples of the halogen anion include a fluoride ion, a chloride ion, a bromide ion, and an iodide ion.

Among them, the anion represented by the general formula (b1-a1) is preferable as the anion portion of the component (B1). Among them, anions represented by any of the formulas (an-1) to (an-3) are more preferable, and anions represented by any of formulas (an-1) Do.

Specific examples of the component (B1) suitable for the following are given.

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In the resist composition of the present embodiment, the component (B1) may be used alone or in combination of two or more.

The content of the component (B1) in the resist composition of the present embodiment is preferably 1 to 80 parts by mass, more preferably 1 to 50 parts by mass, and more preferably 1 to 30 parts by mass based on 100 parts by mass of the component (A) More preferable.

When the content of the component (B1) is not lower than the above preferable lower limit value, the lithography characteristics such as sensitivity, CDU, pattern collapse, resolution performance, LWR (line width roughness) On the other hand, when the content is lower than the upper limit, a uniform solution tends to be obtained when each component of the resist composition is dissolved in an organic solvent, and storage stability as a resist composition is further enhanced.

<Optional ingredients>

The resist composition of the present embodiment may further contain components (optional components) other than the components (A) and (B1) described above.

Examples of such arbitrary components include (B2), (D), (E), (F) and (S)

&Lt; Component (B2): acid generator component &gt;

The resist composition of the present embodiment may contain an acid generator component (hereinafter referred to as "component (B2)") other than the component (B1) within the range that does not impair the effect of the present invention.

The component (B2) is not particularly limited, and any of those proposed as acid generators for chemically amplified resist compositions can be used.

Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisaryl sulfonyl diazomethanes, poly (bis-sulfonyl) diazomethane Diazomethane-based acid generators such as N-benzylsulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

Examples of the onium salt-based acid generators include compounds represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1) (Hereinafter also referred to as &quot; component (b-2) &quot;) or a compound represented by general formula (b-3)

(54)

Wherein R ¹⁰¹ and R ¹⁰⁴ to R ¹⁰⁸ each independently represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ¹⁰¹ to V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ¹⁰¹ to L ¹⁰² each independently represent a single bond or an oxygen atom. L ¹⁰³ to L ¹⁰⁵ each independently represent a single bond, -CO- or -SO ₂ -. m is an integer of 1 or more, and M ' ^{m +} is m-valent onium cation.

{NO ONE}

The anion moiety of the component (b-1) is the same as the anion represented by the above-mentioned general formula (b1-a1).

The anion moiety of the component (b-2) is the same as the anion represented by the aforementioned general formula (b1-a2).

The anion moiety of the component (b-3) is the same as the anion represented by the aforementioned general formula (b1-a3).

{Kationbu}

In the above formulas (b-1), (b-2) and (b-3), M'm ⁺ represents m-valent onium cation and is preferably sulfonium cation or iodonium cation.

m is an integer of 1 or more.

Examples of preferred cation moieties ((M'm ⁺ ) _{1 / m} ) include organic cations represented by the following general formulas (ca-1) to (ca-4).

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[Wherein R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent. R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² may bond together to form a ring with the sulfur atom in the formula. Each of R ²⁰⁸ to R ²⁰⁹ independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ²¹⁰ is an optionally substituted aryl group, optionally substituted alkyl, optionally substituted alkenyl, or optionally substituted -SO ₂ - containing cyclic group. L ²⁰¹ represents -C (= O) - or -C (= O) -O-. Y ²⁰¹ each independently represent an arylene group, an alkylene group or an alkenylene group. x is 1 or 2; W ²⁰¹ represents a (x + 1) linking group.

The aryl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² includes an unsubstituted aryl group having 6 to 20 carbon atoms, preferably a phenyl group or a naphthyl group.

The alkyl group in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² is a chain or cyclic alkyl group and preferably has 1 to 30 carbon atoms.

The alkenyl group in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² preferably has 2 to 10 carbon atoms.

Examples of the substituent which R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, 1) to (ca-r-7), respectively.

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: Wherein each R ' ²⁰¹ independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.

The cyclic group which may have a substituent of R ' ²⁰¹ , the chain alkyl group which may have a substituent, or the chain-like alkenyl group which may have a substituent is the same as R ¹⁰¹ in the above-mentioned formula (b1-a1) , A chain type alkyl group which may have a substituent or a chain type alkyl group which may have a substituent and which is the same as the acid dissociable group represented by the above-mentioned formula (a1-r-2).

R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² , when mutually bonded to form a ring together with the sulfur atom in the formula, may be a hetero atom such as a sulfur atom, an oxygen atom or a nitrogen atom, May be bonded through a functional group such as -SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N (R _N ) - (R _N is an alkyl group having 1 to 5 carbon atoms) do. As the ring to be formed, one ring containing a sulfur atom in the formula in its ring skeleton is preferably 3 to 10 atomic rings including a sulfur atom, and it is particularly preferable that it is a 5 to 7-membered ring. Specific examples of the ring to be formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, thianthrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thiosanthene ring, A thianthrene ring, a phenoxathiine ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring and the like.

Each of R ²⁰⁸ to R ²⁰⁹ independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. When the alkyl group is an alkyl group, they may be bonded to each other to form a ring.

R ²¹⁰ is an optionally substituted aryl group, optionally substituted alkyl, optionally substituted alkenyl, or optionally substituted -SO ₂ - containing cyclic group.

As the aryl group in R ²¹⁰ , an unsubstituted aryl group having from 6 to 20 carbon atoms is exemplified, and a phenyl group or a naphthyl group is preferable.

The alkyl group in R ²¹⁰ is a chain or cyclic alkyl group, preferably having 1 to 30 carbon atoms.

The alkenyl group in R ²¹⁰ preferably has 2 to 10 carbon atoms.

As the -SO ₂ -containing cyclic group which may have a substituent in R ²¹⁰ , "-SO ₂ -containing cyclic group" is preferable, and the group represented by the general formula (a5-r-1) is more preferable Do.

Y ²⁰¹ each independently represent an arylene group, an alkylene group or an alkenylene group.

The arylene group for Y ²⁰¹ includes a group obtained by removing one hydrogen atom from an aryl group exemplified as an aromatic hydrocarbon group for R ¹⁰¹ in the above-mentioned formula (b1-a1).

The alkylene group and alkenylene group in Y ²⁰¹ are groups in which one hydrogen atom has been removed from the groups exemplified as the chain alkyl group and the chain alkenyl group in R ¹⁰¹ in the above-mentioned formula (b1-a1) .

In the above formula (ca-4), x is 1 or 2.

W ²⁰¹ is (x + 1), that is, a divalent or trivalent linking group.

The divalent linking group in W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, and examples of the divalent hydrocarbon group which may have a substituent, the same as Y a ²¹ in the general formula (a2-1) . The bivalent linking group in W ²⁰¹ may be any of linear, branched, and cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group is preferable. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.

Connection of the trivalent group is ²⁰¹ W, and ²⁰¹ W the group 1 to remove the hydrogen atom from the divalent linking group in, in addition to the divalent linking group, and the like which combines the divalent connecting group. As the trivalent linking group in W ²⁰¹ , a group in which two carbonyl groups are bonded to an arylene group is preferable.

Specific examples of the suitable cation represented by the above formula (ca-1) include the cation represented by the following formulas (ca-1-1) to (ca-1-71)

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(58)

[Chemical Formula 59]

G1 represents an integer of 1 to 5, g2 represents an integer of 0 to 20, and g3 represents an integer of 0 to 20.] [wherein, g1, g2 and g3 represent repeating numbers,

(60)

(61)

Wherein R " ²⁰¹ is a hydrogen atom or a substituent, and the substituent is the same as those exemplified as the substituent which R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have.]

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

Specific examples of the suitable cation represented by the above formula (ca-3) include the cation represented by the following formulas (ca-3-1) to (ca-3-6)

(62)

Specific examples of the suitable cation represented by the above formula (ca-4) include cation represented by the following formulas (ca-4-1) to (ca-4-2)

(63)

Among them, the cationic moiety ((M'm ⁺ ) _{1 / m} ) is preferably a cation represented by the general formula (ca-1) Is more preferable.

In the resist composition of the present embodiment, the component (B2) may be used singly or in combination of two or more.

When the resist composition contains the component (B2), the content of the component (B2) in the resist composition is preferably 80 parts by mass or less, more preferably 1 to 50 parts by mass, per 100 parts by mass of the component (A) More preferably 1 to 30 parts by mass.

By setting the content of the component (B2) within the above range, pattern formation is sufficiently performed. Further, when each component of the resist composition is dissolved in an organic solvent, a homogeneous solution is easily obtained and storage stability as a resist composition is improved, which is preferable.

&Lt; Component (D): acid diffusion controller component &gt;

The resist composition of the present embodiment may contain, in addition to the component (A) and the component (B1), an acid diffusion controller component (hereinafter, referred to as "component (D)"). The component (D) acts as a quencher (acid diffusion control agent) for trapping an acid generated by exposure in a resist composition.

The component (D) includes, for example, a photo-degradable base (D1) (hereinafter, referred to as "component (D1)") decomposed by exposure to lose acid diffusion controllability (Hereinafter referred to as &quot; component (D2) &quot;).

· For component (D1)

(D1), the contrast between the exposed portion and the unexposed portion of the resist film can be further improved when the resist pattern is formed.

The component (D1) is not particularly limited as long as it is decomposed by exposure to lose acid diffusion controllability, and the compound represented by the following general formula (d1-1) (hereinafter referred to as the "component (d1-1) , A compound represented by the following general formula (d1-2) (hereinafter referred to as a "component (d1-2)") and a compound represented by the following general formula (d1-3) Quot;) is preferable.

(d1-1) to (d1-3) are decomposed in the exposed portion of the resist film to lose acid diffusion controllability (basicity), so that they do not act as a quencher and act as a quencher in the unexposed portion of the resist film.

&Lt; EMI ID =

[Wherein, Rd Rd ¹ ~ ⁴ is cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl group, or a substituent of the type chain which may have a substituent. It is to be noted that the fluorine atom is not bonded to the carbon atom adjacent to the S atom in Rd ² in the formula (d1-2). Yd ¹ is a single bond or a divalent linking group. m is an integer of 1 or more, and M &lt; ^{m + &gt;} are each independently an m-valent organic cation.

{(d1-1) component}

· · Anion

Formula (d1-1) of, Rd ¹ is a cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl group, or a substituent of the chain which may have a substituent, the formula (b1-a1), respectively May be the same as those of R &lt; ¹⁰¹ &gt;

Among them, Rd ¹ is preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like alkyl group which may have a substituent. Examples of the substituent which these groups may have include a lactone-containing cyclic group represented by the above-mentioned general formulas (a2-r-1) to (a2-r-7), a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, , An ether bond, an ester bond, or a combination thereof. When an ether bond or an ester bond is contained as a substituent, an alkylene group may be interposed. As the substituent in this case, a linking group represented by the above formulas (y-al-1) to (y-al-5) Do.

As the aromatic hydrocarbon group, a phenyl group or a naphthyl group is more preferable.

The aliphatic cyclic group is more preferably a group obtained by removing at least one hydrogen atom from a polycycloalkane such as adamantane, norbornane, isoborane, tricyclodecane, or tetracyclododecane.

The chain-like alkyl group preferably has 1 to 10 carbon atoms, and specific examples thereof 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, Methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2- Ethylhexyl group, ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group.

When the above chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the number of carbon atoms of the fluorinated alkyl group is preferably from 1 to 11, more preferably from 1 to 8, still more preferably from 1 to 4. The fluorinated alkyl group may contain an atom other than a fluorine atom. Examples of the atom other than the fluorine atom include an oxygen atom, a sulfur atom and a nitrogen atom.

As Rd ¹ , it is preferable that some or all of hydrogen atoms constituting the linear alkyl group are fluorinated alkyl groups substituted by fluorine atoms, and fluorinated alkyl groups in which all the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms A linear perfluoroalkyl group) is particularly preferable.

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

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..Cartion

In the formula (d1-1), M ^{m +} is an organic cation of m.

Examples of the organic cation of M ^{m +} are the same as the cation represented by the above general formulas (ca-1) to (ca-4), and the cation represented by the general formula (ca- , More preferably a cation represented by the above formulas (ca-1-1) to (ca-1-71) is more preferable.

The component (d1-1) may be used singly or in combination of two or more.

{(d1-2) component}

· · Anion

Formula (d1-2) of, Rd ^2, the cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl chain which may have a substituent, or a substituent group, the formula (b1-a1) May be the same as those of R &lt; ¹⁰¹ &gt;

Provided that the fluorine atom is not bonded to the carbon atom adjacent to the S atom in Rd ² (not substituted with fluorine). As a result, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability as the component (D) improves.

Rd ² is preferably a chain-like alkyl group which may have a substituent or an aliphatic cyclic group which may have a substituent. The chain-like alkyl group preferably has 1 to 10 carbon atoms, more preferably 3 to 10 carbon atoms. Examples of the aliphatic cyclic group include groups in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (which may have a substituent) It is more preferable that the hydrogen atom is removed.

The hydrocarbon group of Rd ² may have a substituent and examples of the substituent include a substituent which may be possessed by the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, or chained alkyl group) in Rd ¹ of the formula (d1-1) And the like.

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

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..Cartion

In the formula (d1-2), M ^{m +} is an organic cation of ^m, and is the same as M ^{m +} in the formula (d1-1).

The component (d1-2) may be used singly or in combination of two or more.

{(d1-3) component}

· · Anion

In the formula (d1-3) of, Rd ³ is an alkenyl group of chain which may contain a cyclic group, an alkyl group of chain which may have a substituent, or a substituent which may have a substituent, the formula (b1-a1) R ^101, and is preferably a cyclic group, a chain-like alkyl group, or a chain-like alkenyl group containing a fluorine atom. Among them, a fluorinated alkyl group is preferable, and the same as the fluorinated alkyl group of Rd ¹ is more preferable.

Formula (d1-3) of, Rd ⁴ is cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl chain which may have a substituent, or a substituent group, the formula (b1-a1) May be the same as those of R &lt; ¹⁰¹ &gt;

Among them, an alkyl group, alkoxy group, alkenyl group and cyclic group which may have a substituent are preferable.

The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms and specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Part of the hydrogen atoms of the alkyl group Rd is ⁴ may be substituted by a hydroxyl group, a cyano group or the like.

The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso- Butoxy group, and tert-butoxy group. Among them, a methoxy group and an ethoxy group are preferable.

The alkenyl group in Rd ⁴ may be the same as R ¹⁰¹ in the above formula (b1-a1), preferably a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group or a 2-methylpropenyl group . These groups may also have, as a substituent, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

The cyclic group in Rd ⁴ may be the same as R ¹⁰¹ in the above formula (b1-a1), and cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclo An alicyclic group in which at least one hydrogen atom is removed from a cycloalkane such as dodecane, or an aromatic group such as a phenyl group or a naphthyl group is preferable. When Rd ⁴ is an alicyclic group, the resist composition is well dissolved in an organic solvent, whereby lithography characteristics are improved. When Rd ⁴ is an aromatic group, in the case of lithography using EUV as an exposure light source, the resist composition is excellent in light absorption efficiency, and has good sensitivity and lithography characteristics.

Formula (d1-3) of, Yd ¹ is a single bond or a divalent connecting group.

The divalent linking group in Yd ¹ includes, but is not limited to, a divalent hydrocarbon group (aliphatic hydrocarbon group or aromatic hydrocarbon group) which may have a substituent, and a divalent linking group containing a hetero atom. These are the same as the divalent linking group including a divalent hydrocarbon group or a heteroatom which may have a substituent, which is exemplified in the description of the divalent linking group in Ya ²¹ in the formula (a2-1) .

Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, more preferably a methylene group or an ethylene group.

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

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(68)

..Cartion

In the formula (d1-3), M ^{m +} is an organic cation of ^m, and is the same as M ^{m +} in the formula (d1-1).

The component (d1-3) may be used singly or in combination of two or more.

As the component (D1), any one of the components (d1-1) to (d1-3) may be used, or two or more components may be used in combination.

When the resist composition contains the component (D1), the content of the component (D1) in the resist composition is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, per 100 parts by mass of the component (A) , More preferably 1 to 8 parts by mass.

When the content of the component (D1) is lower than the preferable lower limit value, particularly good lithography characteristics and resist pattern shape are easily obtained. On the other hand, if it is less than the upper limit value, the sensitivity can be kept good and the throughput is also excellent.

(D1) Component:

The method for producing the above components (d1-1) and (d1-2) is not particularly limited and can be produced by a known method.

The method for producing the component (d1-3) is not particularly limited, and is produced in the same manner as described in, for example, US2012-0149916.

· For component (D2)

The acid diffusion controller component may contain a nitrogen-containing organic compound component (hereinafter referred to as "component (D2)") which does not correspond to the above-mentioned component (D1).

The component (D2) is not particularly limited as long as it functions as an acid diffusion control agent and does not correspond to the component (D1), and any known component may be used. Among them, an aliphatic amine is preferable, and a secondary aliphatic amine or a tertiary aliphatic amine is particularly preferable.

The aliphatic amine is an amine having at least one aliphatic group, and the aliphatic group preferably has 1 to 12 carbon atoms.

Examples of the aliphatic amine include an amine (alkylamine or alkyl alcohol amine) in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms, or a cyclic amine.

Specific examples of alkylamines and alkylalcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine and n-decylamine; Dialkylamines such as propylamine, di-n-heptylamine, di-n-octylamine and dicyclohexylamine; aliphatic amines such as trimethylamine, triethylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, Alkylamine, alkyl alcohol amine such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, tri-n-octanolamine and the like. Of these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

The cyclic amine includes, for example, a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be a monocyclic (aliphatic monocyclic) amine or a polycyclic (aliphatic polycyclic) amine.

Specific examples of the aliphatic monocyclic amine include piperidine, piperazine and the like.

As the aliphatic polycyclic amines, the number of carbon atoms is preferably from 6 to 10. Specific examples thereof include 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.

Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl } Amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} , Tris [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] amine, triethanolamine triacetate and the like, and triethanolamine triacetate is preferable.

 As the component (D2), an aromatic amine may be used.

Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine .

(D2) may be used singly or in combination of two or more kinds.

When the resist composition contains the component (D2), the component (D2) in the resist composition is usually used in a range of 0.01 to 5 parts by mass based on 100 parts by mass of the component (A). By setting the resistivity to the above range, the resist pattern shape, time-course stability after exposure, and the like are improved.

Component (E): at least one compound selected from the group consisting of an organic carboxylic acid and an oxo acid of phosphorus and a derivative thereof

The resist composition of the present embodiment may contain, as optional components, an organic carboxylic acid and a group consisting of phosphorous oxo acid and derivatives thereof for the purpose of prevention of deterioration of sensitivity, shape of resist pattern, stability over time after exposure, (Hereinafter referred to as &quot; component (E) &quot;) selected from the group consisting of

As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.

Examples of the phosphoric acid include phosphoric acid, phosphonic acid and phosphinic acid. Of these, phosphonic acid is particularly preferable.

Examples of the derivative of the phosphorous oxo acid include an ester in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group. Examples of the hydrocarbon group include an alkyl group having 1 to 5 carbon atoms, an aryl group 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 phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester and phosphonic acid dibenzyl ester.

Examples of derivatives of phosphinic acid include phosphinic acid esters and phenylphosphinic acid.

In the resist composition of the present embodiment, the component (E) may be used singly or in combination of two or more.

When the resist composition contains the component (E), the content of the component (E) is usually in the range of 0.01 to 5 parts by mass based on 100 parts by mass of the component (A).

&Lt; Component (F): Component of fluorine additive &gt;

The resist composition of this embodiment may contain a fluorine additive component (hereinafter referred to as "component (F)") in order to impart water repellency to the resist film.

Examples of the component (F) include, for example, those described in JP-A No. 2010-002870, JP-A No. 2010-032994, JP-A No. 2010-277043, JP-A No. 2011-13569, The fluorinated polymer compound described in the publication No. 2011-128226 can be used.

More specifically, as the component (F), a polymer having a structural unit (f1) represented by the following formula (f1-1) may be mentioned. Examples of the polymer include a polymer (homopolymer) comprising only the constituent unit (f1) represented by the following formula (f1-1), a copolymer of the constituent unit (f1) and the constituent unit (a1) And a structural unit derived from acrylic acid or methacrylic acid and a copolymer of the structural unit (a1). Examples of the structural unit (a1) copolymerized with the structural unit (f1) include structural units derived from 1-ethyl-1-cyclooctyl (meth) acrylate, structural units derived from 1-methyl- Acrylate is preferable.

(69)

[Wherein, R is as defined above and, Rf ¹⁰² and Rf ¹⁰³ each independently represents an alkyl group or halogenated alkyl group having 1 to 5 carbon atoms of hydrogen atom, a halogen atom, a 1 to 5 carbon atoms, Rf ¹⁰² and Rf ¹⁰³ is the same May be different or different. nf ¹ is an integer of 1 to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom.]

In formula (f1-1), R bonded to the carbon atom at the? -Position is the same as described above. As R, a hydrogen atom or a methyl group is preferable.

In the formula (f1-1), examples of the halogen atom of Rf ¹⁰² and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable. Examples of the alkyl group having 1 to 5 carbon atoms represented by Rf ¹⁰² and Rf ^{103 include} the same alkyl groups having 1 to 5 carbon atoms as R described above, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms represented by Rf ¹⁰² and Rf ¹⁰³ include a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms is substituted with a halogen atom. The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable. Among them, Rf ¹⁰² and Rf ¹⁰³ are preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and are preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group.

Formula (f1-1) of, ¹ nf is an integer from 1-5, an integer of 1-3, and more preferably 1 or 2.

In the formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom.

The hydrocarbon group containing a fluorine atom may be any of linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms. Particularly preferred.

The hydrocarbon group containing a fluorine atom preferably has at least 25% of the hydrogen atoms in the hydrocarbon group fluorinated, more preferably at least 50% fluorinated, and more preferably at least 60% Since the hydrophobicity of the resist film at the time of immersion exposure is increased.

Of these, Rf roneun ^101, more preferably a fluorinated hydrocarbon group having 1 to 5 carbon atoms, and a trifluoromethyl _{group, -CH 2 -CF 3, -CH 2} -CF 2 -CF 3, -CH (CF 3) 2, - CH ₂ -CH ₂ -CF ₃ , -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ are particularly preferred.

The mass average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography) of the component (F) is preferably from 1,000 to 50,000, more preferably from 5,000 to 40,000, and most preferably from 10,000 to 30,000. If it is not more than the upper limit of the above range, sufficient solubility for a resist solvent is required for use as a resist, and if it is not lower than the lower limit of this range, dry etching resistance and cross-sectional shape of the resist pattern are good.

The dispersion degree (Mw / Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

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

When the resist composition contains the component (F), the content of the component (F) is usually 0.5 to 10 parts by mass based on 100 parts by mass of the component (A).

&Lt; Component (S): organic solvent component &gt;

The resist composition of the embodiment can be produced by dissolving a resist material in an organic solvent component (hereinafter referred to as "component (S)").

As the component (S), any one that can dissolve each component to be used and can form a homogeneous solution can be used, and any of conventionally known solvents for chemically amplified resist compositions can be appropriately selected and used.

Examples of the component (S) include lactones such as? -Butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl n-pentyl ketone, methyl isopentyl ketone, Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol and dipropylene glycol; compounds having ester bonds such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; Derivatives of polyhydric alcohols such as monohydric alcohols or compounds having an ether bond such as monomethyl ether, monoethyl ether, monopropyl ether, and monobutyl ether of monobutyl ether or monophenyl ether of the compound having ester bond [Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether Cyclic ethers such as dioxane, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, methyl pyruvate, methyl methoxypropionate, ethoxypropionate Ethyl, and the like; anhydrides such as anisole, ethylbenzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, Aromatic organic solvents such as rhenium, cymene and mesitylene, dimethylsulfoxide (DMSO) and the like.

In the resist composition of the present embodiment, the component (S) may be used singly or as a mixed solvent of two or more kinds.

Among them, PGMEA, PGME,? -Butyrolactone, EL, and cyclohexanone are preferable.

A mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The compounding ratio (mass ratio) may be suitably determined in consideration of the compatibility of the PGMEA and the polar solvent, and is preferably within the range of 1: 9 to 9: 1, more preferably 2: 8 to 8: 2 desirable.

More specifically, when EL or cyclohexanone is blended as a polar solvent, the mass ratio of PGMEA: EL or cyclohexanone is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. When PGME is blended as a polar solvent, the mass ratio of PGMEA: PGME is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, still more preferably 3: 7: 3. Mixed solvents of PGMEA, PGME and cyclohexanone are also preferred.

Further, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and? -Butyrolactone is also preferable. In this case, as the mixing ratio, the mass ratio of the former and the latter is preferably 70:30 to 95: 5.

The amount of the component (S) to be used is not particularly limited and is appropriately set in accordance with the coating film thickness at a concentration applicable to a substrate or the like. In general, the component (S) is used so that the solid concentration of the resist composition is in the range of 1 to 20 mass%, preferably 2 to 15 mass%.

The resist composition of the present embodiment may be further added with a miscible additive, for example, an additive resin for improving the performance of a resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, a halation inhibitor, .

(Resist Pattern Forming Method)

The resist pattern forming method according to the second aspect of the present invention is a resist pattern forming method comprising the steps of forming a resist film on a support using the resist composition according to the first aspect, exposing the resist film, And developing the resist pattern to form a resist pattern.

As one embodiment of such a resist pattern forming method, for example, there can be mentioned a resist pattern forming method which is carried out as follows.

First, the resist composition of the above-described embodiment is coated on a support by a spinner or the like, and baking (post-apply baking (PAB)) treatment is performed at a temperature of 80 to 150 캜 for 40 to 120 seconds, , The resist film is formed for 60 to 90 seconds.

Next, using the exposure apparatus such as an ArF exposure apparatus, an electron beam lithography apparatus, and an EUV exposure apparatus, an exposure or mask pattern interposed between a mask (mask pattern) having a predetermined pattern formed thereon is interposed (Post exposure bake (PEB)) treatment is carried out at a temperature of 80 to 150 ° C for 40 to 120 seconds, preferably 60 to 120 seconds, for example, after performing selective exposure by drawing by direct irradiation of an electron beam 90 seconds.

Next, the resist film is developed. The developing treatment is carried out using a developing solution (organic developing solution) containing an alkaline developing solution in the case of the alkali developing process and an organic solvent in the case of the solvent developing process.

After the developing treatment, rinsing treatment is preferably carried out. In the case of the alkaline development process, rinsing is preferably performed using purified water, and in the case of the solvent development process, a rinsing solution containing an organic solvent is preferably used.

In the case of the solvent developing process, a treatment for removing the developing solution or the rinsing liquid adhering to the pattern by the supercritical fluid may be performed after the developing treatment or the rinsing treatment.

After the development treatment or the rinsing treatment, drying is performed. In some cases, a baking process (post-baking) may be performed after the above developing process.

In this manner, a resist pattern can be formed.

The support is not particularly limited and conventionally known ones can be used, and examples thereof include a substrate for electronic components and a substrate having a predetermined wiring pattern formed thereon. More specifically, a metal substrate such as a silicon wafer, copper, chromium, iron or aluminum, or a glass substrate can be given. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold and the like can be used.

As the support, an inorganic and / or organic film may be formed on the above-described substrate. As the inorganic film, an inorganic anti-reflection film (inorganic BARC) can be mentioned. Examples of the organic film include an organic antireflection film (organic BARC) and an organic film such as a lower organic film in the multilayer resist method.

Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are formed on a substrate, and a resist pattern formed on the upper resist film is used as a mask And patterning the underlying organic film to form a pattern with a high aspect ratio. That is, according to the multilayer resist method, since the required thickness can be ensured by the lower organic film, the resist film can be made thinner and a fine pattern with a high aspect ratio can be formed.

In the multilayer resist method, basically, a method of forming a two-layer structure of an upper resist film and a lower layer organic film (two-layer resist method), and a method of forming an intermediate layer (metal thin film or the like) And a method of forming a multilayer structure of three or more layers (three-layer resist method).

The wavelength to be used for exposure is not particularly limited and may be selected from the group consisting of ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam) It can be carried out using radiation. The resist composition has high availability as a KrF excimer laser, an ArF excimer laser, EB or EUV and is more useful as an ArF excimer laser, EB or EUV, and particularly useful as EB or EUV.

The exposure method of the resist film may be a conventional exposure (dry exposure) or an immersion exposure (liquid immersion lithography) in an inert gas such as air or nitrogen.

The liquid immersion exposure is an exposure method in which the space between the resist film and the lens in the lowermost position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than that of air and exposure (immersion exposure) is performed in this state.

As the immersion medium, a solvent which is larger than the refractive index of air and has a refractive index smaller than the refractive index of the exposed resist film is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.

Examples of the solvent that is larger than the refractive index of air and has a refractive index smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicone solvent, and a hydrocarbon solvent.

Specific examples of the fluorine-based inert liquid include liquids containing fluorine-based compounds such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , C ₅ H ₃ F ₇ , And preferably has a boiling point of 70 to 180 ° C, more preferably 80 to 160 ° C. If the fluorine-based inert liquid has a boiling point in the above-mentioned range, it is preferable that the medium used for liquid immersion can be removed by a simple method after the end of exposure.

As the fluorine-based inert liquid, a perfluoroalkyl compound in which the hydrogen atoms of the alkyl group are all substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.

Specific examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C), and perfluoroalkylamine compounds include perfluoro (Boiling point 174 占 폚).

As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility and the like.

Examples of the alkali developing solution used in the developing treatment in the alkali development process include an aqueous solution of 0.1 to 10 mass% tetramethylammonium hydroxide (TMAH).

The organic solvent contained in the organic developing solution used in the developing treatment in the solvent developing process may be any solvent that can dissolve the component (A) (component (A) before exposure) and may be appropriately selected from known organic solvents. Specific examples thereof include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents and ether solvents, hydrocarbon solvents and the like.

The ketone-based solvent is an organic solvent containing C-C (= O) -C in the structure. The ester solvent is an organic solvent containing C-C (= O) -O-C in the structure. The alcohol-based solvent is an organic solvent containing an alcoholic hydroxyl group in its structure. The "alcoholic hydroxyl group" means a hydroxyl group bonded to the carbon atom of the aliphatic hydrocarbon group. The nitrile-based solvent is an organic solvent containing a nitrile group in its structure. The amide-based solvent is an organic solvent containing an amide group in the structure. The ether-based solvent is an organic solvent containing C-O-C in its structure.

In the organic solvent, an organic solvent containing a plurality of functional groups characterizing each of the above-mentioned solvents is also present in the structure. In this case, it is assumed that the solvent corresponds to any solvent species including the functional group of the organic solvent. For example, diethylene glycol monomethyl ether corresponds to any of alcohol-based solvents and ether-based solvents in the above-mentioned classifications.

The hydrocarbon-based solvent is a hydrocarbon solvent which is made of a hydrocarbon which may be halogenated and has no substituent other than a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

As the organic solvent contained in the organic developing solution, a polar solvent is preferable among them, and a ketone solvent, an ester solvent, a nitrile solvent and the like are preferable.

Examples of the ketone-based solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl Ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonyl acetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthyl ketone, Isophorone, propylene carbonate,? -Butyrolactone, and methyl amyl ketone (2-heptanone). Of these, methylamyl ketone (2-heptanone) is preferable as the ketone-based solvent.

Examples of the ester-based solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl lactate, methoxyacetate, ethoxyacetate, propylene glycol monomethyl ether acetate, ethylene glycol Monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, Diethylene glycol monomethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, - Methode Propyleneglycol monomethyl ether acetate, propyleneglycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, propyleneglycol monomethylether acetate, propyleneglycol monomethylether acetate, Propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, Propyleneglycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, , Propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, , Ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, Methoxypropionate, propyl-3-methoxypropionate, and the like. Of these, butyl acetate is preferable as the ester-based solvent.

The nitrile-based solvent includes, for example, acetonitrile, propionitrile, valeronitrile, butyronitrile, and the like.

If necessary, known additives may be added to the organic developer. As the additive, for example, a surfactant can be mentioned. The surfactant is not particularly limited and, for example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used. The surfactant is preferably a nonionic surfactant, more preferably a nonionic fluorine surfactant or a nonionic silicone surfactant.

When a surfactant is blended, the blending amount thereof is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, more preferably 0.01 to 0.5 mass%, based on the total amount of the organic developer.

The developing treatment can be carried out by a known developing method. For example, a developing solution is dipped in a developing solution for a predetermined time (dip method), a developing solution is mounted on the surface of the support by surface tension, A method of spraying a developing solution onto the surface of a support (spraying method), a method of continuously developing a developing solution while scanning a developing solution nozzle at a constant speed on a support rotating at a constant speed Dispensing method) and the like.

Examples of the organic solvent to be contained in the rinsing liquid used for the rinsing treatment after the developing treatment in the solvent developing process include those suitably selected from the organic solvents exemplified as the organic solvents used for the organic developing solution, Can be used. Typically, at least one solvent selected from a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent and an ether solvent is used. Among them, at least one selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent and an amide-based solvent is preferable, and at least one selected from an alcoholic solvent and an ester- Alcohol-based solvents are particularly preferred.

The alcoholic solvent used in the rinsing liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be any of linear, branched or cyclic. Specific examples thereof include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, - octanol, benzyl alcohol, and the like. Among them, 1-hexanol, 2-heptanol and 2-hexanol are preferable, and 1-hexanol and 2-hexanol are more preferable.

Any one of these organic solvents may be used alone, or two or more of them may be used in combination. It may be mixed with an organic solvent or water other than the above. However, considering the developing characteristics, the blending amount of water in the rinsing liquid is preferably 30 mass% or less, more preferably 10 mass% or less, still more preferably 5 mass% or less, and most preferably 3 mass% % Or less is particularly preferable.

A known additive may be added to the rinsing liquid if necessary. As the additive, for example, a surfactant can be mentioned. Examples of the surfactant include the same ones as described above. Nonionic surfactants are preferable, and nonionic fluorine surfactants or nonionic silicone surfactants are more preferable.

When a surfactant is blended, the blending amount thereof is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, more preferably 0.01 to 0.5 mass%, based on the total amount of the rinse liquid.

The rinsing treatment (rinsing treatment) using the rinsing liquid can be carried out by a known rinsing method. Examples of the rinsing method include a method (rotation coating method) of continuously extracting the rinsing liquid on a support rotating at a constant speed, a method (dip method) of immersing the support in a rinsing liquid for a predetermined time And a method of spraying the rinsing liquid (spray method).

The resist composition of the present embodiment described above contains the compound (B1) represented by the general formula (b1) as the acid generator component. Therefore, in the resist pattern forming method of the above-described embodiment, high sensitivity can be achieved while satisfactorily maintaining the lithography characteristics such as resolution performance, roughness improvement, and shape.

The component (B1) has a directional ring (R ^b1 ) having a specific electron-withdrawing group. In addition, the component (B1) comprises, in addition to the aromatic ring (R ^b1 ), two aromatic rings (R ^b21 and R ^b22 ) and a thiophene ring located therebetween and sharing a bond constituting each aromatic ring And has a cyclic group. The component (B1) having such a structure has an increased efficiency of generating an acid by exposure.

The resist composition containing the component (B1) and the base component (A) tends to have a high sensitivity to an exposure light source, and a high sensitivity to an EB or EUV light source is likely to be obtained in particular. Therefore, the resist composition of the present embodiment is particularly suitable as a photosensitive material for lithography for EB or EUV.

(compound)

The compound related to the third embodiment of the present invention is represented by the following general formula (b1).

(70)

^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 (provided that the aromatic ring is benzene Ring, the electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond to form a ring with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).]

The compound relating to this third embodiment is the same compound as the (B1) component in the description of the resist composition related to the above-mentioned first embodiment.

[Method for producing compound (component (B1)]]

The component (B1) can be produced by a known method.

As the production method of the component (B1), for example, there can be mentioned a production method comprising the first and second steps shown below.

The compound used in each step may be a commercially available compound or a synthesized compound.

The solvent in each of the reactions in the first and second steps may be any solvent which can dissolve the compound used in the respective steps and does not react with the compound. Examples of the solvent include dichloromethane, dichloroethane, chloroform, tetra N, N-dimethylformamide, dimethylacetamide, dimethylsulfoxide, acetonitrile, propionitrile and the like.

First step

In the first step, a reaction solution containing the compound (III) which is a precursor is obtained by mixing the compound (I), the compound (II) and the TMS-X "in a solvent and conducting a reaction.

The mixing time for carrying out this mixing is suitably set according to the reactivity of the compounds, the reaction temperature, and the like.

After obtaining a reaction mixture, water is added to the reaction solution obtained, and the mixture is subjected to solvent extraction from the water phase and concentrated to dryness (dry solid) to obtain the compound (IV).

(71)

[ ^Wherein R ^b1 , R ^b21 , R ^b22 and Z are the same as R ^b1 , R ^b21 , R ^b22 and Z in the general formula (b1). X _h represents a halogen atom. TMS means trimethylsilyl group. X "indicates counter no.]

Examples of the halogen atom in X _h include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

The counter anion in X "includes Br ^- , Cl ^- , CF ₃ SO ₃ ^- and the like.

· Second step

In the second step, the aimed compound (b1-1) ((B1)) is obtained by mixing the compound (III) and the salt exchange compound (IV) in a solvent (salt exchange reaction).

The temperature (reaction temperature) in carrying out the mixing is preferably about 0 to 100 캜, more preferably about 0 to 50 캜.

The mixing time is appropriately set depending on the reactivity of the compounds, the reaction temperature, etc. For example, the mixing time is preferably from 10 minutes to 24 hours, more preferably from 10 minutes to 12 hours.

(72)

[Wherein, R ^b1, R ^{b21, b22} R, Z and X ^- is the same ^as-is, R ^b1, R ^{b21, b22} R, Z and X in the general formula (b1). X "indicates counter no. M ' ⁺ is ammonium cation.]

After completion of the salt exchange reaction, the compound in the reaction liquid may be isolated and purified. For the isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography and the like can be appropriately used in combination.

The structure of the compound thus obtained can be measured by ¹ H-nuclear magnetic resonance (NMR) spectroscopy, ¹³ C-NMR spectroscopy, ¹⁹ F-NMR spectroscopy, infrared absorption spectroscopy, mass spectrometry , An elemental analysis method, an X-ray crystal diffraction method, and the like.

(Acid generator)

The acid generator according to the fourth aspect of the present invention comprises the compound according to the third aspect described above.

Such an acid generator is useful as an acid generator component for a chemically amplified resist composition. By using such an acid generator component in a chemically amplified resist composition, lithography characteristics such as exposure allowance, CDU, resolution performance and LWR are favorably maintained in the formation of a resist pattern, and high sensitivity is achieved. In particular, high sensitivity is easily obtained for an EB or EUV light source.

Example

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

In the present embodiment, the compound represented by the formula (1) is referred to as "compound (1)" and the compound represented by the other formula is represented in the same manner.

<Production Example of Compound>

(Example 1)

Magnesium metal (13.75 g) and tetrahydrofuran (THF) were added to a 1000 ml three-necked flask and stirred at 50 占 폚 to obtain a solution. To this solution, a tetrahydrofuran solution (236.16 g) of 3,5-difluorobromobenzene (108.08 g) was added dropwise and the mixture was heated and stirred for 1 hour to obtain a 3,5-difluorophenylmagnesium bromide solution Lt; / RTI &gt;

Trimethylsilyltrifluoromethanesulfonate (TMSTF) (248.93 g) was added to a tetrahydrofuran solution (323.61 g) of sulfoxide A (37.38 g) in a 2000 ml three-necked flask, Solution. To the reaction solution, the above-mentioned 3,5-difluorophenyl magnesium bromide solution was added and aging was performed for 1 hour.

The reaction was followed by liquid chromatography (LC), and pure water was added to stop the reaction. From the aqueous phase, the mixture was extracted with dichloromethane and concentrated to obtain 50 g of the desired precursor (1).

(73)

The obtained precursor (1) was subjected to NMR measurement, and the structure thereof was identified from the following measurement results.

The salt exchange compound (1) (4.34 g) was added to a dichloromethane solution of the precursor (1) (5.00 g) and stirred at room temperature (salt exchange reaction) for 30 minutes to obtain a reaction mixture solution.

After stirring, pure water (78.9 g) was added to the reaction mixture to stop the reaction. The water phase was removed, and the organic phase was washed four times with pure water.

After washing, the organic phase was concentrated to obtain 5.75 g of the desired compound (B1-4) as a solid.

In the following reaction formulas, " ^- OTf" means triflate anion.

&Lt; EMI ID =

(Example 2)

A salt exchange reaction or the like was carried out in the same manner as in Example 1 except that the salt-exchange compound was changed to obtain the desired compound (B1-7).

That is, the salt exchange compound (2) (4.50 g) was added to a dichloromethane solution of precursor (1) (5.00 g) and stirred at room temperature (salt exchange reaction) for 30 minutes to obtain a reaction mixture solution .

After stirring, pure water (65.9 g) was added to the reaction mixture to stop the reaction. The water phase was removed, and the organic phase was washed four times with pure water.

After washing, the organic phase was concentrated to dryness to obtain 5.49 g of the aimed compound (B1-7) as a solid.

(75)

(Examples 3 to 38)

(B1-1) to (B1-3), (B1-5), (B1-3), and (B1-3) were carried out in the same manner as in Example 2, Compound (B1-6), compounds (B1-8) to (B1-38) were obtained.

(Example 39)

Magnesium metal (12.83 g) and tetrahydrofuran (THF) were added to a 1000 ml three-necked flask and stirred at 50 占 폚 to obtain a solution. To this solution, a tetrahydrofuran solution (235.15 g) of 3-trifluoromethylbromobenzene (117.58 g) was added dropwise and the mixture was heated and stirred for 1 hour to prepare a 3-trifluoromethylphenylmagnesium bromide solution .

Trimethylsilyltrifluoromethanesulfonate (TMSTF) (232.27 g) was added to a tetrahydrofuran solution (301.95 g) of sulfoxide A (34.88 g) in a 2000 ml three-necked flask, Solution. To the reaction solution was added the above-mentioned 3-trifluoromethylphenyl magnesium bromide solution, and aging was performed for 1 hour.

The reaction was followed by liquid chromatography (LC), and pure water was added to stop the reaction. From the aqueous phase, the mixture was extracted with dichloromethane and concentrated to obtain 50 g of a target precursor (2).

[Formula 76]

The obtained precursor (2) was subjected to NMR measurement, and the structure thereof was identified from the following measurement results.

The salt exchange compound (1) (5.33 g) was added to a dichloromethane solution of the precursor (2) (5.00 g) and stirred at room temperature (salt exchange reaction) for 30 minutes to obtain a reaction mixture solution.

After stirring, pure water (92.7 g) was added to the reaction mixture to stop the reaction. The water phase was removed, and the organic phase was washed four times with pure water.

After washing, the organic phase was concentrated to dryness to obtain 7.42 g of the aimed compound (B1-42) as a solid.

In the following reaction formulas, " ^- OTf" means triflate anion.

[Formula 77]

(Example 40)

A salt exchange reaction or the like was carried out in the same manner as in Example 39 except that the salt-exchange compound was changed to obtain the intended compound (B1-45).

That is, the salt-exchanging compound (2) (4.20 g) was added to a dichloromethane solution of the precursor (2) (5.00 g) and stirred at room temperature (salt exchange reaction) for 30 minutes to obtain a reaction mixture solution .

After stirring, pure water (66.5 g) was added to the reaction mixture to stop the reaction. The water phase was removed, and the organic phase was washed four times with pure water.

After washing, the organic phase was concentrated to obtain 5.74 g of a desired compound (B1-45) as a solid.

(78)

(Examples 41 to 76)

(B1-39) to a compound (B1-41), a compound (B1-43), and a compound (B1-43) were subjected to salt exchange reaction and the like in the same manner as in Example 40, (B1-44), and compounds (B1-46) to (B1-76).

Structures of the cations and anions of the obtained compounds (B1-1) to (B1-76) and the results of NMR measurement are shown below.

(79)

The cations of the compounds (B1-1) to (B1-38)

The cations of the compounds (B1-39) to (B1-76)

(80)

The anion of the compound (B1-1) and the compound (B1-39)

The anion of the compound (B1-2) and the compound (B1-40)

[Formula 81]

The anion of the compound (B1-3) and the compound (B1-41)

The anion of the compound (B1-4) and the compound (B1-42)

(82)

The anion of the compound (B1-5) and the compound (B1-43)

The anion of the compound (B1-6) and the compound (B1-44)

(83)

The anion of the compound (B1-7) and the compound (B1-45)

The anion of the compound (B1-8) and the compound (B1-46)

(84)

The anion of the compound (B1-9) and the compound (B1-47)

The anion of the compound (B1-10) and the compound (B1-48)

(85)

The anion of the compound (B1-11) and the compound (B1-49)

The anion of the compound (B1-12) and the compound (B1-50)

&Lt; EMI ID =

The anion of the compound (B1-13) and the compound (B1-51)

The anion of the compound (B1-14) and the compound (B1-52)

[Chemical Formula 87]

The anion of the compound (B1-15) and the compound (B1-53)

¹⁹ F-NMR (376 MHz, DMSO-d 6)? (Ppm) = -73.7

The anion of the compound (B1-16) and the compound (B1-54)

¹⁹ F-NMR (376 MHz, DMSO-d6)? (Ppm) = -161.1, -149.7, -131.6, -76.2

The anion of the compound (B1-17) and the compound (B1-55)

[Formula 88]

The anion of the compound (B1-18) and the compound (B1-56)

¹⁹ F-NMR (376 MHz, DMSO-d6)? (Ppm) = -77.3, -111.5, -118.1,

The anion of the compound (B1-19) and the compound (B1-57)

¹⁹ F-NMR (376 MHz, DMSO-d 6)? (Ppm) = -75.0

The anion of the compound (B1-20) and the compound (B1-58)

¹⁹ F-NMR (376 MHz, DMSO-d6)? (Ppm) = -77.3, -112.5, -121.7

(89)

The anion of the compound (B1-21) and the compound (B1-59)

¹⁹ F-NMR (376 MHz, DMSO-d 6)? (Ppm) = -116.9, -123.0

The anion of the compound (B1-22) and the compound (B1-60)

¹⁹ F-NMR (376 MHz, DMSO-d6)? (Ppm) = -75.9, -76.0, -114.7

The anion of the compound (B1-23) and the compound (B1-61)

(90)

The anion of the compound (B1-24) and the compound (B1-62)

The anion of the compound (B1-25) and the compound (B1-63)

The anion of the compound (B1-26) and the compound (B1-64)

[Formula 91]

The anion of the compound (B1-27) and the compound (B1-65)

The anion of the compound (B1-28) and the compound (B1-66)

&Lt; EMI ID =

The anion of the compound (B1-29) and the compound (B1-67)

The anion of the compound (B1-30) and the compound (B1-68)

&Lt; EMI ID =

The anion of the compound (B1-31) and the compound (B1-69)

The anion of the compound (B1-32) and the compound (B1-70)

(94)

The anion of the compound (B1-33) and the compound (B1-71)

The anion of the compound (B1-34) and the compound (B1-72)

&Lt; EMI ID =

The anion of the compound (B1-35) and the compound (B1-73)

The anion of the compound (B1-36) and the compound (B1-74)

&Lt; EMI ID =

The anion of the compound (B1-37) and the compound (B1-75)

The anion of the compound (B1-38) and the compound (B1-76)

¹⁹ F-NMR (376 MHz, DMSO-d 6)? (Ppm) = -129.6, -158.7, -163.2

&Lt; Production Example of Base Component (Polymer) &gt;

Polymers A-1 to A-18 used in this example were obtained by radical polymerization using the following monomers, each providing a constituent unit constituting each polymer, at a predetermined molar ratio.

[Formula 97]

The copolymer composition ratio (ratio (molar ratio) of each constitutional unit in the polymer) of the polymer obtained by ¹³ C-NMR to polymer A-1 to A-18, mass average molecular weight in terms of standard polystyrene (Mw ) And a molecular weight dispersion (Mw / Mn) are shown in Table 1.

&Lt; Preparation of resist composition &gt;

 (Examples 77 to 110 and Comparative Examples 1 to 15)

The components shown in Tables 2 to 5 were mixed and dissolved to prepare resist compositions for each example.

In Tables 2 to 5, the respective abbreviations have the following meanings respectively. The values in [] are the compounding amount (parts by mass).

(A) -1 to (A) -18: Polymers A-1 to A-18 as described above.

(B1) -1: An acid generator comprising the above compound (B1-4).

(B1) -2: An acid generator comprising the above compound (B1-7).

(B1) -3: An acid generator comprising the above compound (B1-42).

(B1) -4: An acid generator comprising the above compound (B1-45).

(B2) -1 to (B2) -5: An acid generator comprising compounds (B2-1) to (B2-5) represented by the following formulas (B2-1) to (B2-5), respectively.

(98)

(D-1) to (D-10) represented by the following formulas (D-1) to (D-10).

[Formula 99]

(100)

(S) -1: mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 20/80 (by mass).

&Lt; Formation of resist pattern &

On each of the 8-inch silicon substrates subjected to hexamethyldisilazane (HMDS) treatment, the resist compositions of the respective examples were applied using a spinner, and subjected to a prebake (PAB) treatment on a hot plate at a temperature of 100 DEG C for 60 seconds And dried to form a resist film having a film thickness of 30 nm.

Next, using a 1: 1 line-and-space pattern having a line width of 50 to 26 nm and a target size at an acceleration voltage of 100 kV using an electron beam drawing apparatus JEOL-JBX-9300FS (manufactured by Nippon Electronics Co., Ltd.) (Hereinafter referred to as &quot; LS pattern &quot;).

Subsequently, alkali development was carried out at 23 占 폚 for 60 seconds using a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.).

Thereafter, water was rinsed with pure water for 60 seconds, and post-exposure baking (PEB) treatment was performed at 110 캜 for 60 seconds.

As a result, a 1: 1 LS pattern having a line width of 50 to 26 nm was formed.

[Evaluation of optimum exposure dose (Eop)] [

The optimum exposure dose Eop (μC / cm 2) at which the LS pattern of the target size was formed was determined by the above-described method of forming a resist pattern. This is shown in the table as "Eop (μC / cm 2)".

[Evaluation of resolution]

The minimum dimension of the pattern to be resolved without collapsing when the LS pattern is formed by slightly increasing the exposure amount from the optimum exposure amount Eop in the Eop, specifically, by the scanning electron microscope S-9380 (manufactured by Hitachi High- Ltd.). This is shown in the table as &quot; resolution performance (nm) &quot;.

[Evaluation of LWR (line with roughness)] [

With respect to the LS pattern formed in the &lt; formation of a resist pattern &gt;, 3σ, which is a scale representing LWR, was obtained. This is shown in the table as &quot; LWR (nm) &quot;.

&Quot; 3 sigma &quot; was measured by measuring the line position at 400 points in the longitudinal direction of the line by using a scanning electron microscope (accelerating voltage 800 V, trade name: S-9380, Hitachi High-Technologies Corporation) (Unit: nm) of 3 times the deviation (sigma).

The smaller the value of 3?, The smaller the roughness of the line sidewalls and the more uniform LS pattern was obtained.

[Evaluation of LS pattern shape]

The shape of the LS pattern formed by the above <formation of resist pattern> was observed by a measurement SEM (scanning electron microscope, acceleration voltage 800 V, trade name: S-9220, manufactured by Hitachi, Ltd.) &Quot;

From the results shown in Tables 6 to 9, it can be confirmed that the resist composition according to the embodiment to which the present invention is applied can achieve high sensitivity while satisfactorily maintaining the lithographic characteristics such as resolution performance, roughness improvement and shape .

&Lt; Time-course stability of the compound &

(Example 111, Comparative Example 16)

Each component shown in Table 10 was mixed and dissolved to prepare a test liquid for evaluation (solid concentration of 10% by mass).

In Table 10, the respective abbreviations have the following meanings respectively.

(B1) -5: a compound (B1-77) represented by the following formula (B1-77) (the precursor (1) described above).

(B2) -6: a compound (B2-6) represented by the following formula (B2-6).

(D) -1: A compound (D-1) represented by the following formula (D-1).

(S) -2: Propylene glycol monomethyl ether acetate (PGMEA).

(101)

[Evaluation of Time Stability]

Test solutions of each example were left at room temperature (23 ° C) for 30 days and stored.

After such storage, the decomposition ratios of the components (B1) and (B2) contained in the test solution were measured, and the time-course stability of the compounds was evaluated. These results are shown in Table 10 as &quot; decomposition ratio (%) &quot;.

The decomposition ratios of the components (B1) and (B2) were measured as follows.

The reversed-phase high-performance liquid chromatography (HPLC) measurement was carried out using a diluted solution accurately diluted with 1 g of acetonitrile as a test sample (0.1 g) before and after the preservation.

The percentage of the change in the peak area derived from the component (B1) and the peak area derived from the component (B2) before and after storage in the chromatogram obtained by this measurement was regarded as the decomposition rate (%).

From the results shown in Table 10, the compound (B1-77) in which the fluorine atom is bonded to the meta position has a significantly lower decomposition rate than the compound (B2-6) in which the fluorine atom is bonded to the para position and the time- I can confirm that it is excellent.

The compound (B1-77) is stable even when used in combination with the compound (D-1), and thus is useful as an acid generator of a resist composition.

Claims (7)

As a resist composition which generates an acid upon exposure and changes solubility in a developer by the action of an acid,
A base component (A) in which solubility in a developing solution is changed by the action of an acid,
A resist composition comprising a compound (B1) represented by the following general formula (b1).
[Chemical Formula 1]

[ ^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 , provided that the aromatic ring is a benzene ring , The electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded through a sulfur atom, an oxygen atom, a carbonyl group or a single bond, and form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond, and form a ring together with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).] The method according to claim 1,
Wherein the content of the compound (B1) is 1 to 50 parts by mass relative to 100 parts by mass of the base component (A). 3. The method according to claim 1 or 2,
The base component (A) comprises the polymer compound (A1)
The polymer compound (A1) has the structural unit (a1) containing an acid-decomposable group whose polarity is increased by the action of an acid. A step of forming a resist film by using the resist composition according to any one of claims 1 to 3 on the support, a step of exposing the resist film, and a step of developing the resist film after exposure to form a resist pattern A method for forming a resist pattern. 5. The method of claim 4,
And exposing the resist film to EUV (Extreme Ultraviolet) or EB (electron beam) in the step of exposing the resist film. A compound represented by the following general formula (b1).
(2)

[ ^Wherein R ^b1 represents an aromatic ring having an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b10 , provided that the aromatic ring is a benzene ring , The electron-withdrawing group is bonded to the meta position of at least one of the benzene rings). R ^b10 represents an alkyl group, a fluorinated alkyl group or an aryl group. R ^b21 and R ^b22 each independently represent an aromatic ring which may have an electron-withdrawing group selected from the group consisting of a fluorine atom, a trifluoromethyl group, a nitro group, a cyano group and -SO ₂ R ^b20 . R ^b20 represents an alkyl group, a fluorinated alkyl group or an aryl group. Z represents a sulfur atom, an oxygen atom, a carbonyl group or a single bond. R ^b1 and R ^b21 may be bonded through a sulfur atom, an oxygen atom, a carbonyl group or a single bond, and form a ring with the sulfur atom in the formula. R ^b1 and R ^b22 may be bonded to each other through a sulfur atom, an oxygen atom, a carbonyl group or a single bond, and form a ring together with the sulfur atom in the formula. X ^- represents counter no (except BF ₄ ^- ).] An acid generator comprising the compound according to claim 6.