JP2008273886A - Oxime sulfonate-based compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new compound utilizable as a component of a resist composition, especially as an acid-generating agent. <P>SOLUTION: The compound is represented by general formula (I) [wherein, R<SP>1</SP>is an organic group except a (meth)acryloyl group; R<SP>2</SP>is a linear or branched 1-5C alkylene group or a fluorinated alkylene group; R<SP>3</SP>is a substituted or nonsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group; and R<SP>4</SP>is a 1-5C fluorinated alkyl group]. Preferably, R<SP>3</SP>is a substituted or nonsubstituted 1-naphthyl group or 2-naphthyl group, and R<SP>1</SP>is a substituted or nonsubstituted alkyl group. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel oxime sulfonate-based compound.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed to radiation such as light or an electron beam through a mask on which a predetermined pattern is formed. And a development process is performed to form a resist pattern having a predetermined shape on the resist film.
A resist material in which the exposed portion changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has rapidly progressed due to advances in lithography technology.
As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but now mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. In addition, studies have been made on F ₂ excimer lasers, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like having shorter wavelengths than these excimer lasers.

Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions.
As a resist material satisfying such requirements, a chemically amplified resist containing a base resin whose alkali solubility is changed by the action of an acid and an acid generator that generates an acid upon exposure is used.
For example, a positive chemically amplified resist contains an acid dissociable, dissolution inhibiting group and contains a resin component (base resin) whose alkali solubility is increased by the action of an acid and an acid generator component. When acid is generated from the acid generator by exposure during pattern formation, the acid dissociable, dissolution inhibiting group is detached from the resin component by the action of the acid, and the exposed portion becomes alkali-soluble.
Currently, as a resist base resin used in ArF excimer laser lithography and the like, a resin (acrylic resin) having a structural unit derived from (meth) acrylic acid ester in its main chain because of its excellent transparency near 193 nm ) And the like are generally used (see, for example, Patent Document 1). Here, “(meth) acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position. “(Meth) acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. “(Meth) acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position.
In addition, various acid generators used in chemically amplified resists have been proposed so far, such as onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, Diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators and the like are known.
JP 2003-241385 A

In the future, as further progress in lithography technology and expansion of application fields are expected, there is an increasing demand for new materials that can be used for lithography applications.
This invention is made | formed in view of the said situation, Comprising: It aims at providing the novel compound which can be utilized as a component of a resist composition, especially an acid generator.

In order to achieve the above object, the present invention employs the following configuration.
That is, the first aspect of the present invention is a compound represented by the following general formula (I) (hereinafter sometimes referred to as compound (I)).

［式中、Ｒ^１は（メタ）アクリロイル基を除く有機基であり；Ｒ^２は直鎖状または分岐鎖状の炭素数１〜５のアルキレン基またはフッ素化アルキレン基であり；Ｒ^３は置換または無置換のフェニル基、１−ナフチル基または２−ナフチル基であり；Ｒ^４は炭素数１〜５のフッ素化アルキル基である。］

[Wherein, R ¹ is an organic group excluding a (meth) acryloyl group; R ² is a linear or branched alkylene group having 1 to 5 carbon atoms or a fluorinated alkylene group; and R ³ is substituted. or unsubstituted phenyl group, a 1-naphthyl group or a 2-naphthyl group; R ⁴ is a fluorinated alkyl group of 1 to 5 carbon atoms. ]

In the present specification and claims, unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups.
The “lower alkyl group” is an alkyl group having 1 to 5 carbon atoms.
The “halogenated alkyl group” is a group in which 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 “alkylene group” includes linear, branched and cyclic divalent saturated hydrocarbon groups unless otherwise specified.

  The compound (I) of the present invention is a novel compound, and the compound can be used as a component of a resist composition, particularly as an acid generator.

<< Compound (I) >>
The compound (I) of the present invention is represented by the general formula (I).
The wavy line in the formula (I) includes two types of geometric isomers in which the general formula (I) is a structure represented by the following general formula (Ia) and a structure represented by the following general formula (Ib). Indicates that it is a thing. The wavy lines in the following chemical formulas have the same meaning.
That is, in the compound (I), there are two kinds of geometric isomer structures (anti isomer and syn isomer) due to a double bond between nitrogen and carbon.
The compound (I) may be a compound represented by the general formula (Ia), a compound represented by the general formula (Ib), or a mixture thereof.

［式中、Ｒ^１〜Ｒ^４は前記と同じである。］

[Wherein, R ^{1 to} R ⁴ are the same as described above. ]

In the formula (I), the organic group for R ¹ may be other than the (meth) acryloyl group, and is not particularly limited.
Here, “(meth) acryloyl group” in the present specification and claims means one or both of an acryloyl group and a methacryloyl group.
Examples of the organic group for R ¹ include a substituted or unsubstituted alkyl group.
Here, the substituted alkyl group means that part or all of the hydrogen atoms of the unsubstituted alkyl group are substituted with a substituent.
The unsubstituted alkyl group may be linear, branched or cyclic, and may be a combination of a linear or branched alkyl group and a cyclic alkyl group.
The linear or branched alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10, more preferably 1 to 8, more preferably 1 to 6, and particularly preferably 1 to 4 Preferably 1 is most preferred. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
Examples of the cyclic alkyl group include a group in which one hydrogen atom is removed from a monocycloalkane or a polycycloalkane such as bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples include monocycloalkyl groups such as cyclopentyl group and cyclohexyl group, and polycycloalkyl groups such as adamantyl group, norbornyl group, isobornyl group, tricyclodecanyl group, and tetracyclododecanyl group.
A combination of a linear or branched alkyl group and a cyclic alkyl group includes a group in which a cyclic alkyl group is bonded as a substituent to a linear or branched alkyl group, and a substituent to the cyclic alkyl group. And a group in which a linear or branched alkyl group is bonded.

Examples of the substituent that the alkyl group may have include an unsaturated aliphatic hydrocarbon group, an aromatic hydrocarbon group, a substituent containing a hetero atom, and the like.
Here, “aliphatic” in the claims and the specification is a relative concept with respect to aromatics, and is defined to mean a group, a compound, or the like that does not have aromaticity.
Examples of the unsaturated aliphatic hydrocarbon group include an alkenyl group. Examples of the alkenyl group include those having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms, and a vinyl group and a propenyl group are preferable.
Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, biphenyl group, fluorenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, and phenanthryl group. An alkylaryl group in which an alkyl group is bonded as a substituent to the aryl group; an arylalkyl group in which an aryl group is bonded as a substituent to the alkyl group; Examples of the alkylaryl group or the alkyl group in the arylalkyl group include those similar to the unsubstituted alkyl group.

A heteroatom in the “substituent containing a heteroatom” is an atom other than a carbon atom and a hydrogen atom, for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (fluorine atom, chlorine atom, iodine atom, bromine atom, etc.) Etc.
Examples of the substituent containing a hetero atom include an oxygen atom (═O), a halogen atom, a halogenated alkyl group, a hydroxyl group, a carboxy group, an amino group, a cyano group, a heterocyclic group, and a general formula R ²¹ -A- [ In the formula, R ²¹ is a hydrocarbon group, and A is a linking group containing a hetero atom. ] Etc. which are represented by these.
Examples of the heterocyclic group include heteroaliphatic cyclic groups such as a tetrahydropyranyl group and a tetrahydrofuranyl group, and heteroaromatic cyclic groups such as a furfuryl group, a thiophenyl group, and a pyridyl group.

In the general formula R ^{21 -A-} group represented by a hydrocarbon group R ²¹ may be either an aliphatic hydrocarbon group may be an aromatic hydrocarbon group. Examples of the aliphatic hydrocarbon group include an alkyl group and an unsaturated aliphatic hydrocarbon group. Examples of the alkyl group include those similar to the unsubstituted alkyl group. Examples of the unsaturated aliphatic hydrocarbon group include the same groups as those listed above as the substituent that the alkyl group may have.
Examples of the linking group containing a heteroatom of A include a group containing a heteroatom exemplified in the substituent containing a heteroatom, such as —O—, —C (═O) —, and —C (═O). —O—, —NH—, —NR ²² (R ²² is an alkyl group) —, —NH—C (═O) —, ═N— and the like can be mentioned.
Specific examples of the group represented by the general formula R ²¹ -A- include an alkoxy group, a (meth) acryloyl group, an alkylcarbonyl group, and an alkylcarbonyloxy group.

In the present invention, R ¹ is preferably an alkyl group substituted with an unsaturated aliphatic hydrocarbon group or an aromatic hydrocarbon group, and an alkyl group substituted with a vinyl group, a 1-naphthyl group or a 2-naphthyl group. Particularly preferred.

The alkylene group for R ² may be either linear or branched, and is preferably linear. 1-5 are preferable, as for carbon number of this alkylene group, 1-3 are more preferable, 2 or 3 is more preferable, and 2 is especially preferable. Specifically, a methylene group, ethylene group, trimethylene group (— (CH ₂ ) ₃ —), propylene group (—C (CH ₃ ) —CH ₂ —), tetramethylene group (— (CH ₂ ) ₄ —) , A pentamethylene group (— (CH ₂ ) ₅ —) and the like, among which an ethylene group is preferable.
Examples of the fluorinated alkylene group for R ² include groups in which some or all of the hydrogen atoms in the alkylene group have been substituted with fluorine atoms. The fluorinated alkylene group may be a group (partially fluorinated alkylene group) in which some of the hydrogen atoms of the alkylene group are substituted with fluorine atoms, and the group in which all of the hydrogen atoms are substituted with fluorine atoms. (Perfluoroalkylene group) may be used.
In the present invention, R ² is preferably a fluorinated alkylene group, more preferably a perfluoroalkylene group, and most preferably a tetrafluoroethylene group.

R ³ may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted 1-naphthyl group, or a substituted or unsubstituted 2-naphthyl group.
Here, the substituted phenyl group, 1-naphthyl group or 2-naphthyl group is a substituent in which part or all of the hydrogen atoms of the unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group are substituted. Indicates that
Examples of the substituent in the substituted phenyl group, 1-naphthyl group, or 2-naphthyl group include a halogen atom, an alkyl group, and a halogenated alkyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The alkyl group or the halogenated alkyl group preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and still more preferably 1. The halogenated alkyl group is preferably a fluorinated alkyl group.
The number of substituents in the substituted phenyl group is in the range of 1 to 5, preferably 1 to 2. The number of substituents in the substituted 1-naphthyl group or 2-naphthyl group is in the range of 1 to 7, more preferably 1 to 2.
In the present invention, R ³ is preferably a substituted or unsubstituted 1-naphthyl group or 2-naphthyl group.

The fluorinated alkyl group for R ⁴ may be linear, branched or cyclic, preferably linear or branched, and more preferably linear. The fluorinated alkyl group preferably has 2 to 5 carbon atoms, more preferably 4 or 5, and most preferably 4.
The fluorinated alkyl group may be a partially fluorinated alkyl group, a perfluoroalkyl group, or a perfluoroalkyl group.

  As the compound (I), a compound represented by the following general formula (I-1) or (I-2) is particularly preferable.

［式中、ａは１〜２０の整数であり、ｂは１〜１０の整数であり、ｆは１〜５の整数である。］

[Wherein, a is an integer of 1 to 20, b is an integer of 1 to 10, and f is an integer of 1 to 5. ]

In formula (I-1), a is an integer of 1 to 20, preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, particularly preferably 1 to 4, and most preferably 1.
b is an integer of 1 to 10, an integer of 1 to 8 is preferable, an integer of 1 to 5 is more preferable, and 2 is most preferable.
The naphthyl group may be a 1-naphthyl group or a 2-naphthyl group.
f is preferably an integer of 2 to 5, more preferably 4 or 5, and most preferably 4.

<< Production Method of Compound (I) >>
Although it does not specifically limit as a manufacturing method of compound (I), As a preferable method, for example, compound (III) represented by the following general formula (III) from the compound (II) represented by the following general formula (II) (Hereinafter referred to as compound (III) synthesis step), a step of obtaining compound (IV) represented by the following general formula (IV) from the compound (III) (hereinafter referred to as compound (IV) synthesis step). ), A step of obtaining a compound (V) represented by the following general formula (V) from the compound (IV) (hereinafter referred to as a compound (V) synthesis step), and the compound (V) and the following general formula (VI) And a compound (VI) represented by formula (I)) to obtain a compound (I) (hereinafter referred to as a compound (I) synthesis step).

Is the same as the formula (II) ~ ^R 1 in ^{(VI), R 2, R} 3, R 1 in ^{R 4} each Formula ^{(I), R 2, R} 3, R 4.
X _h in the formula (VI) is a halogen atom, and examples thereof include a bromine atom, a chlorine atom, an iodine atom, and a fluorine atom. The X _h, in terms of reactivity, a fluorine atom or a chlorine atom is preferable.

"Compound (III) synthesis process"
To obtain the compound (III) (alcohol form) from the compound (II) (aldehyde compound) is, for example, in a reaction solvent, compound ^(II), such as R 4 Si _{(CH 3) 3,} and ^{R 4} The method of making it react with the silane compound which has is mentioned.
As compound (II), a commercially available product may be used or synthesized. As a method for synthesizing compound (II), a conventionally known method for synthesizing aromatic aldehydes may be applied.
Although it does not specifically limit as a reaction solvent, The thing which can melt | dissolve the compound (II) which is a raw material is preferable, and a tetrahydrofuran, a dioxane, dimethoxyethane etc. are mentioned specifically ,.
The reaction is preferably performed in the presence of a base such as cesium fluoride or potassium fluoride.
The reaction temperature is preferably 0 to 80 ° C, more preferably 20 to 40 ° C. The reaction time is preferably 0.5 to 24 hours, more preferably 1 to 12 hours, and particularly preferably 1 to 3 hours.
After completion of the reaction, compound (III) in the reaction solution may be isolated and purified. For isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, crystallization, recrystallization, chromatography, distillation and the like can be used alone or in combination of two or more.

"Compound (IV) synthesis process"
Compound (IV) (ketone body) can be obtained from compound (III) (alcohol body) by oxidizing compound (III) (alcohol body). As the oxidation method, a method generally used for converting alcohol into a ketone can be used.
Specific examples include, for example, a method of reacting compound (III) with an oxidant in a reaction solvent, such as a diphosphorus pentoxide-dimethyl sulfoxide (DMSO) method, a method of contacting with an organic acid peroxide, a metal A method of contacting with an oxide (for example, permanganic acid method, chromic anhydride / pyridine method) or the like can be used.
Although it does not specifically limit as a reaction solvent, The thing which can melt | dissolve the compound (III) which is a raw material is preferable, and a dimethylformamide (DMF), a methylene chloride, an acetic acid etc. are mentioned specifically ,.
For example, in the diphosphorus pentoxide-DMSO method, the reaction temperature is preferably 0 to 100 ° C, more preferably 20 to 60 ° C. The reaction time is preferably 0.5 to 12 hours, more preferably 1 to 2 hours.
After completion of the reaction, the compound (IV) in the reaction solution may be isolated and purified as described above.

"Compound (V) synthesis process"
As a method for obtaining the compound (V) (oxime form) from the compound (IV) (ketone form), a method generally used for producing an oxime from a ketone can be used. For example, in a reaction solvent, the compound can be used. (IV) and the hydroxyamine or its derivative (s) are mixed, and the method of heating to predetermined reaction temperature is mentioned.
Although it does not specifically limit as a reaction solvent, What can melt | dissolve the compound (IV) which is a raw material is preferable, Specifically, tetrahydrofuran, acetonitrile, a pyridine, etc. are mentioned. Moreover, these solvents may be used in combination with an aqueous solvent such as methanol-modified ethanol, ethanol, or propanol.
The reaction temperature is preferably 0 to 100 ° C, more preferably 60 to 100 ° C, and particularly preferably 90 to 100 ° C. The reaction time is preferably 1 to 12 hours, more preferably 2 to 7 hours, and particularly preferably 3 to 5 hours.

“Compound (I) Synthesis Process”
As a method of reacting compound (V) (oxime form) and compound (VI), for example, compound is dissolved in a reaction solvent, and compound (VI) is added to the solution, preferably in the presence of a base. A method is mentioned.
Any reaction solvent may be used as long as it can dissolve the starting compound (V). Specifically, acetone, dimethylformamide (DMF), dimethylacetamide, dimethylsulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, and the like. Is mentioned.
Examples of the base include organic bases such as 4-dimethylaminopyridine (DMAP), triethylamine and pyridine; and inorganic bases such as K ₂ CO ₃ and Cs ₂ CO ₃ .
The reaction temperature is preferably -20 to 60 ° C, more preferably 0 to 30 ° C, and particularly preferably 10 to 20 ° C. The reaction time is more preferably 1 to 12 hours, and particularly preferably 1 to 3 hours.
After completion of the reaction, the compound (I) in the reaction solution may be isolated and purified. For isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, crystallization, recrystallization, chromatography and the like can be used alone or in combination of two or more.

The compounds used in the present step (VI) is not particularly limited, for example, when X _h in the general formula (VI) is exemplified the case of compounds is a fluorine atom (F) as an example, the following general formula (VI -1) and the compound (VI-2) represented by the following general formula (VI-2) are represented by the general formula MF [wherein M is silver (Ag), Represents cesium (Cs) or potassium (K). And a method of reacting in the presence of a solvent (for example, Journal of Fluorine Chemistry, 1990, Vol. 46, No. 1, 21-38)).

［式中、Ｒ^１〜Ｒ^２は前記と同じである。］

[Wherein, R ^{1 to} R ² are the same as described above. ]

Compound (VI-2) can be obtained, for example, by the method described in “J. Amer. Chem. Soc.”, 1960, Vol. 82, page 6181. .
As MF, any of AgF, KF, and CsF may be sufficient, and AgF is preferable.
The solvent is preferably a glyme solvent such as diglyme, triglyme or tetraglyme, or a nitrile solvent such as acetonitrile or adiponitrile, and particularly preferably a glyme solvent.
The reaction temperature is preferably 0 to 150 ° C. When using AgF as MF, 0-60 degreeC is more preferable. When using KF or CsF as MF, 50-150 degreeC is more preferable.
The pressure during the reaction is not particularly limited, but when the reaction temperature is higher than the reflux temperature at normal pressure, it is preferable to carry out the reaction in a pressurized system using an autoclave or the like.
The reaction time is preferably 1 to 24 hours in the case of AgF, and preferably 5 to 100 hours in the case of KF or CsF.
After completion of the reaction, the compound (VI) in the reaction solution may be isolated and purified. For isolation and purification, conventionally known methods can be used. For example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography and the like can be used alone or in combination of two or more.

In addition, the compound in which R ¹ in the general formula (VI) is a substituted or unsubstituted 1-naphthyl group or an alkyl group substituted with a 2-naphthyl group is a novel compound. The compound is useful for the production of compound (I).
Specific examples of the compound include, for example, a compound in which R ¹ is a substituted or unsubstituted 2-naphthylmethyl group (hereinafter referred to as compound (VI-11)), and R ¹ is substituted or unsubstituted 1-naphthyl. And a compound that is a methyl group (hereinafter referred to as compound (VI-12)).

In this invention, you may perform the process (isomer control process) which isolate | separates each isomer before or after the compound (I) synthetic | combination process as needed. Thereby, compound (V) or compound (I) can be obtained as either single isomer.
That is, the compound (V) obtained in the compound (V) synthesis step is usually a geometric isomer represented by the following general formula (Va) and a geometric isomer represented by the following general formula (Vb). It is a mixture. One of these geometric isomers is an anti isomer and the other is a syn isomer.

［式中、Ｒ^３およびＲ^４は前記と同じである。］

[Wherein, R ³ and R ⁴ are the same as defined above. ]

In general, when any one isomer (isomer-controlled compound (V)) is used as compound (V), compound (I) obtained in the next step is also isomer-controlled. That is, when the compound (I) synthesis step is performed using the geometric isomer represented by the general formula (Va), the geometric isomer represented by the following general formula (Ia) is obtained. When the compound (I) synthesis step is performed using the geometric isomer represented by Vb), the geometric isomer represented by the general formula (Ib) is obtained.
On the other hand, when the compound (I) synthesis step is performed without isomer control, a mixture thereof is obtained. When compound (I) is synthesized using such a mixture of isomers, the resulting compound (I) has a geometric isomer represented by the general formula (Ia) and a geometric isomer represented by the general formula (Ib). It becomes a mixture with isomers. Therefore, when an isomer control step is performed after the compound (I) synthesis step, any one of those geometric isomers can be obtained.

The isomer control can be performed by a conventionally known method. For example, recrystallization, liquid chromatography, column chromatography and the like can be used alone or in combination of two or more.
The isomer control is preferably performed after dissolving the reaction product in a predetermined solvent and heating the solution under an acid catalyst. As a result, one of the two isomers changes to the isomer with higher thermal stability, so that one isomer can be obtained in a high yield. Examples of the acid catalyst include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid and the like.
Any solvent can be used as long as it can dissolve the compound (V). Preferably, alcohols such as methanol and ethanol, acetone, acetonitrile and the like are used.
Whether or not the obtained compound (V) and compound (I) are isomer mixtures or single isomers, or the ratio of each isomer when they are isomer mixtures, etc., is ¹⁹ F-nucleus It can be confirmed by magnetic resonance spectroscopy (NMR), thin layer chromatography (TLC), liquid chromatography and the like.

The structure of the compound obtained in each of the above steps is as follows: ¹ H-NMR, ¹³ C-NMR, ¹⁹ F-NMR, infrared absorption spectroscopy (IR), mass spectrometry (MS), elemental analysis, X-ray crystal diffraction It can confirm by general organic analysis methods, such as.

The compound (I) of the present invention is a novel compound that has not been known so far.
Compound (I) can be used as a component of the resist composition, and is particularly suitable as an acid generator.
That is, when compound (I) is irradiated with radiation, bond cleavage occurs in the molecule, and R ¹ —O—R ² —SO ₃ H and C (R ³ ) (R ⁴ ) = NOH are obtained. Decompose. That is, an acidic group (—SO ₃ H) is formed by irradiation with radiation.
In general, a chemically amplified resist composition is blended with an acid generator and a resin component (base resin) whose solubility in an alkaline developer is changed by the action of an acid generated from the acid generator. . Therefore, when the compound (I) of the present invention is added to a chemically amplified resist composition as an acid generator, the alkali solubility of the resin component is caused by the action of acidic groups generated from the compound (I) upon irradiation (exposure) of radiation. Increases and a resist pattern can be formed.
Moreover, the resist composition containing the compound (I) of the present invention has good lithography properties such as sensitivity and resolution, and can form a fine resist pattern having a line width of a line and space pattern of 120 nm or less, for example. .
In addition, the compound (I) of the present invention is transparent to light having a wavelength of 200 nm or less, particularly about 193 nm, compared to acid generators conventionally used in chemically amplified resist compositions such as triphenylsulfonium salts. High nature. Therefore, in the resist composition containing the compound (I) of the present invention, the compounding amount of the component (B) can be increased as compared with the conventional resist composition.

  The compound (I) of the present invention is useful as a resist composition as described above. Hereinafter, preferred embodiments of the resist composition containing the compound (I) will be described.

≪Resist composition≫
The resist composition of this embodiment comprises a base material component (A) whose solubility in an alkaline developer is changed by the action of an acid (hereinafter referred to as “component (A)”) and an acid generator component (B) that generates an acid upon exposure. ) (Hereinafter referred to as the component (B)), wherein the component (B) contains the compound (I) of the present invention.
When the resist film formed using such a resist composition is selectively exposed, an acid is generated from the component (B) in the resist film in the exposed portion. Since the acid changes the solubility of the component (A) in an alkaline developer, a resist pattern is formed by alkali-developing the resist film.
The resist composition may be a positive resist composition or a negative resist composition.

<(B) component>
The component (B) includes the compound (I) of the present invention.
In the component (B), as the compound (I), one type may be used alone, or two or more types may be used in combination.
In the component (B), the ratio of the compound (I) is preferably 50 to 100% by mass, more preferably 75 to 100% by mass, and further preferably 90 to 100% by mass.

In the resist composition of this embodiment, the component (B) may further contain an acid generator component (B2) that generates an acid upon exposure (hereinafter referred to as the component (B2)) other than the compound (I). .
The component (B2) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists 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 bisarylsulfonyldiazomethanes, and poly (bissulfonyl) diazomethanes. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  As the onium salt acid generator, for example, a compound represented by the following general formula (b-1) or (b-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”は、それぞれ独立に、アリール基またはアルキル基を表し；式（ｂ−１）におけるＲ^１”〜Ｒ^３”のうち、いずれか２つが相互に結合して式中のイオウ原子と共に環を形成してもよく；Ｒ^４”は、直鎖状、分岐鎖状または環状のアルキル基またはフッ素化アルキル基を表し；Ｒ^１”〜Ｒ^３”のうち少なくとも１つはアリール基を表し、Ｒ^５”〜Ｒ^６”のうち少なくとも１つはアリール基を表す。］

[Wherein, R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group; among R ¹ ″ to R ³ ″ in formula (b-1), Any two may be bonded together to form a ring with the sulfur atom in the formula; R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group; R ¹ At least one of “˜R ³ ” represents an aryl group, and at least one of “R ⁵ ″ to R ⁶ ” represents an aryl group.]

In formula (b-1), R ¹ ″ to R ³ ″ each independently represents an aryl group or an alkyl group. In addition, any two of R ¹ ″ to R ³ ″ in formula (b-1) may be bonded to each other to form a ring together with the sulfur atom in the formula.
Further, at least one of R ¹ ″ to R ³ ″ represents an aryl group. Of R ¹ ″ to R ³ ″, two or more are preferably aryl groups, and most preferably all of R ¹ ″ to R ³ ″ are aryl groups.
The aryl group for R ¹ ″ to R ³ ″ is not particularly limited, and is, for example, an aryl group having 6 to 20 carbon atoms, in which part or all of the hydrogen atoms are alkyl groups, alkoxy groups It may or may not be substituted with a group, a halogen atom, a hydroxyl group or the like. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.
The alkyl group that may be substituted for the hydrogen atom of the aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and is a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Is most preferred.
As the alkoxy group that may be substituted for the hydrogen atom of the aryl group, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, Most preferred is a tert-butoxy group.
The halogen atom that may be substituted for the hydrogen atom of the aryl group is preferably a fluorine atom.
The alkyl group for R 1 ^{"~R 3",} is not particularly limited, for example, linear C1-10, branched or cyclic alkyl group, and the like. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.
Among these, R ¹ ″ to R ³ ″ are most preferably a phenyl group or a naphthyl group, respectively.

When any two of R ¹ ″ to R ³ ″ in the formula (b-1) are bonded to each other to form a ring together with the sulfur atom in the formula, a 3 to 10 membered ring including the sulfur atom is formed. It is preferable that a 5- to 7-membered ring is formed. When any two of R ¹ ″ to R ³ ″ in formula (b-1) are bonded to each other to form a ring together with the sulfur atom in the formula, the remaining one may be an aryl group preferable. Examples of the aryl group include the same aryl groups as those described above for R ¹ ″ to R ³ ″.

R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group.
The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group is a cyclic group as indicated by R ¹ ″ and preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and 6 carbon atoms. Most preferably, it is -10.
The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms. The fluorination rate of the fluorinated alkyl group (ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. Particularly, all the hydrogen atoms are substituted with fluorine atoms. A fluorinated alkyl group (perfluoroalkyl group) is preferable because the strength of the acid is increased.
R ⁴ ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.

In formula (b-2), R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group. At least one of R ⁵ ″ to R ⁶ ″ represents an aryl group. It is preferable that all of R ⁵ ″ to R ⁶ ″ are aryl groups.
As the aryl group for R ⁵ ″ to R ⁶ ″, the same as the aryl groups for R ¹ ″ to R ³ ″ can be used.
As the alkyl group for R ⁵ ″ to R ⁶ ″, the same as the alkyl groups for R ¹ ″ to R ³ ″ can be used.
Among these, it is most preferable that all of R ⁵ ″ to R ⁶ ″ are phenyl groups.
"As ^{R 4} in the formula (b-1)" ^{R 4} in the In the formula (b-2) include the same as.

Specific examples of the onium salt acid generators represented by the formulas (b-1) and (b-2) include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium. Trifluoromethane sulfonate or nonafluorobutane sulfonate; triphenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; tri (4-methylphenyl) sulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its Nonafluorobutanesulfonate; dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropane sulfonate or its nonafluorobutane sulfonate; trifluoromethane sulfonate of monophenyldimethylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; trifluoromethane sulfonate of diphenyl monomethylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate (4-methylphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; Trifluoromethanesulfonate of tri (4-tert-butyl) phenylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutanesulfonate; trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate; trifluoromethane sulfonate of di (1-naphthyl) phenylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1-phenyltetrahydrothiophenium trifluoromethane sulfonate, its heptafluoropropane sulfonate Or nonafluorobutanesulfonate thereof; 1- (4-methylphenyl) ) Tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1- (4-ethoxynaphthalene-1- Yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonaflu 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1-phenyltetrahydrothiopyranium trifluoromethanesulfonate , Its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (4-hydroxyphenyl) tetrahydrothiopyranium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl -4-Hydroxyphenyl) tetrahydrothiopyranium trifluoromethanesulfonate, its heptafluoropropanes Honeto or nonafluorobutanesulfonate; 1- (4-methylphenyl) trifluoromethanesulfonate tetrahydrothiophenium Pila chloride, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, and the like.
In addition, onium salts in which the anion portion of these onium salts is replaced with methanesulfonate, n-propanesulfonate, n-butanesulfonate, or n-octanesulfonate can also be used.

  In addition, in the general formula (b-1) or (b-2), an onium salt-based acid generator in which the anion moiety is replaced with an anion moiety represented by the following general formula (b-3) or (b-4). Can also be used (the cation moiety is the same as (b-1) or (b-2)).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Most preferably, it has 3 carbon atoms.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, the strength of the acid increases as the number of hydrogen atoms substituted with fluorine atoms increases, and high-energy light or electron beam of 200 nm or less The ratio of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all. Are a perfluoroalkylene group or a perfluoroalkyl group in which a hydrogen atom is substituted with a fluorine atom.

  Moreover, the sulfonium salt which has a cation part represented by the following general formula (b-5) or (b-6) can also be used as an onium salt type | system | group acid generator.

［式中、Ｒ^４１〜Ｒ^４６はそれぞれ独立してアルキル基、アセチル基、アルコキシ基、カルボキシ基、水酸基またはヒドロキシアルキル基であり；ｎ_１〜ｎ_５はそれぞれ独立して０〜３の整数であり、ｎ_６は０〜２の整数である。］

[Wherein R ^{41 to} R ⁴⁶ are each independently an alkyl group, acetyl group, alkoxy group, carboxy group, hydroxyl group or hydroxyalkyl group; n _{1 to} n ₅ are each independently an integer of 0 to 3; There, _{n 6} is an integer of 0-2. ]

In R ^{41 to} R ⁴⁶ , the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group, and a methyl group, an ethyl group, a propyl group, an isopropyl group, n A butyl group or a tert-butyl group is particularly preferable.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a linear or branched alkoxy group, and particularly preferably a methoxy group or an ethoxy group.
The hydroxyalkyl group is preferably a group in which one or more hydrogen atoms in the alkyl group are substituted with a hydroxy group, and examples thereof include a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group.
When the symbols n _{1 to} n ₆ attached to R ^{41 to} R ⁴⁶ are integers of 2 or more, the plurality of R ^{41 to} R ⁴⁶ may be the same or different.

The anion part of the sulfonium salt having a cation part represented by the formula (b-5) or (b-6) is not particularly limited, and is the same as the anion part of the onium salt acid generators proposed so far. It may be a thing. Examples of the anion moiety include fluorinated alkyl sulfonate ions such as the anion moiety (R ^{4 ″} SO ₃ ⁻ ) of the onium salt acid generator represented by the general formula (b-1) or (b-2). An anion moiety represented by the general formula (b-3) or (b-4), etc. Among them, a fluorinated alkyl sulfonate ion is preferable, and a fluorinated alkyl sulfonic acid having 1 to 4 carbon atoms. Ion is more preferable, and linear perfluoroalkylsulfonic acid ions having 1 to 4 carbon atoms are particularly preferable, and specific examples thereof include trifluoromethylsulfonic acid ions, heptafluoro-n-propylsulfonic acid ions, and nonafluoro-n. -Butyl sulfonate ion etc. are mentioned.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation with radiation. is there. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

（式（Ｂ−１）中、Ｒ^３１、Ｒ^３２はそれぞれ独立に有機基を表す。）

(In formula (B-1), R ³¹ and R ³² each independently represents an organic group.)

The organic groups of R ³¹ and R ³² are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), etc.) You may have.
As the organic group for R ^31, a linear, branched, or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms or a fluorinated alkyl group having 1 to 4 carbon atoms which has no substituent.

As the organic group for R ^32, a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.
R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

［式（Ｂ−２）中、Ｒ^３３は、シアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３４はアリール基である。Ｒ^３５は置換基を有さないアルキル基またはハロゲン化アルキル基である。］

[In Formula (B-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

［式（Ｂ−３）中、Ｒ^３６はシアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３７は２または３価の芳香族炭化水素基である。Ｒ^３８は置換基を有さないアルキル基またはハロゲン化アルキル基である。ｐ”は２または３である。］

[In Formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. ^R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]

In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and carbon atoms. Numbers 1 to 6 are most preferable.
R ³³ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³³ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred.

As the aryl group of R ³⁴ , one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group. And a heteroaryl group in which a part of carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom or a nitrogen atom. Among these, a fluorenyl group is preferable.
The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

The alkyl group or halogenated alkyl group having no substituent for R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.
R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³⁵ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred is the strength of the acid generated. Most preferred is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent for R ³⁶ is the same as the alkyl group or halogenated alkyl group having no substituent for R ^33. Is mentioned.
Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .
Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include the same alkyl groups or halogenated alkyl groups having no substituent as R ³⁵ described above.
p ″ is preferably 2.

Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope N-tenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.
Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [chemical formula 18] to [chemical formula 19]), pamphlet of International Publication No. 04/074242, An oxime sulfonate-based acid generator disclosed in Examples 1 to 40) on pages 65 to 85 can also be suitably used.
Moreover, the following can be illustrated as a suitable thing.

  Of the above exemplified compounds, the following four compounds are preferred.

Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Examples include bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.
Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.
Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

  (B2) As a component, these acid generators may be used individually by 1 type, and may be used in combination of 2 or more type.

  0.5-60 mass parts is preferable with respect to 100 mass parts of (A) component, and, as for content of (B) component in a resist composition, 1-50 mass parts is more preferable. By setting it within the above range, pattern formation is sufficiently performed. Moreover, since a uniform solution is obtained and storage stability becomes favorable, it is preferable.

<(A) component>
The component (A) is not particularly limited, and has been proposed as a substrate component for a chemically amplified resist composition, such as a resist composition for ArF excimer laser, a resist composition for KrF excimer laser, etc. It is possible to select and use an arbitrary one from among a large number of existing ones.
Here, the “base material component” is an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved and a nano-level pattern is easily formed.
The organic compound having a molecular weight of 500 or more includes a low molecular weight organic compound having a molecular weight of 500 or more and less than 2000 (hereinafter referred to as a low molecular compound) and a high molecular weight organic compound having a molecular weight of 2000 or more (hereinafter referred to as a polymer compound). )). As the low molecular weight compound, a non-polymer is usually used. As the polymer compound, a resin (polymer, copolymer) is usually used. In the case of a resin, a polystyrene-reduced weight average molecular weight by GPC (gel permeation chromatography) is used as the “molecular weight”. Hereinafter, the term “resin” refers to a resin having a molecular weight of 2000 or more.
The substrate component may be a low molecular compound, a resin, or a mixture thereof.

When the resist composition is a negative resist composition, as the component (A), an alkali-soluble resin that is usually dissolved in an alkali developer is used, and at the same time, a crosslinking agent ( C) (hereinafter referred to as component (C)) is blended.
In such a negative resist composition, when an acid is generated from the component (B), cross-linking occurs between the component (A) and the component (C) by the action of the acid, and the solubility of the component (A) in the alkaline developer is increased. Decreases. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the negative resist composition on the substrate is selectively exposed, the lower layer film for thermal lithography below it absorbs the light and generates heat. Is generated. This heat is transmitted to the resist film thereon, and the heat acts on the component (B) in the resist film to generate heat. The acid action lowers the solubility of the exposed portion in the alkaline developer, while the solubility of the unexposed portion in the alkaline developer does not change. Therefore, a resist pattern can be formed by alkali development.

As the alkali-soluble resin, a resin having a structural unit derived from at least one selected from α- (hydroxyalkyl) acrylic acid or a lower alkyl ester of α- (hydroxyalkyl) acrylic acid has a low swelling. A resist pattern can be formed, which is preferable.
Here, in the present specification, the “structural unit” means a monomer unit (monomer unit) constituting a polymer compound (polymer, copolymer).
α- (Hydroxyalkyl) acrylic acid includes acrylic acid in which a hydrogen atom is bonded to the α-position carbon atom to which the carboxy group is bonded, and a hydroxyalkyl group (preferably having 1 to 5 carbon atoms) in the α-position carbon atom. One or both of the α-hydroxyalkylacrylic acid to which the hydroxyalkyl group is bonded.
Further, as an alkali-soluble resin, a novolak resin having a hydrophilic group, a hydroxystyrene resin, an (α-lower alkyl) acrylate resin, a structural unit derived from hydroxystyrene and an (α-lower alkyl) acrylate ester Examples thereof include a copolymer resin containing a derived structural unit.
Examples of the (α-lower alkyl) acrylate resin include a structural unit derived from an (α-lower alkyl) acrylate ester having a hydroxyl group-containing group such as a fluorinated hydroxyalkyl group or a hydroxyalkyl group. Resin.
The mass average molecular weight (Mw; polystyrene-converted mass average molecular weight by gel permeation chromatography) of the alkali-soluble resin is preferably 2000 to 30000, more preferably 2000 to 10000, and still more preferably 3000 to 8000. By setting it within this range, a good dissolution rate in an alkali developer can be obtained, which is preferable from the viewpoint of high resolution. When the weight average molecular weight is lower within this range, good characteristics tend to be obtained.

When the resist composition is a positive resist composition, as the component (A), a base component that usually has an acid dissociable, dissolution inhibiting group and increases the solubility in an alkali developer by the action of an acid is used. It is done.
In such a positive resist composition, when an acid is generated from the component (B), the acid dissociable, dissolution inhibiting group is dissociated by the action of the acid, and the solubility of the component (A) in the alkaline developer increases. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the positive resist composition on the substrate is selectively exposed, the underlying lower layer film for thermal lithography absorbs the light and generates heat. Is generated. This heat is transmitted to the resist film thereon, and the heat acts on the component (B) in the resist film to generate heat. Then, the action of the acid increases the solubility of the exposed portion in the alkaline developer, while the solubility in the unexposed portion of the alkaline developer does not change, so that a resist pattern can be formed by alkali development.

As the (A) component of the positive resist composition, the following (A-1) component and / or (A-2) component are more preferable.
-(A-1) component: Resin which has an acid dissociable, dissolution inhibiting group.
Component (A-2): a low molecular compound having an acid dissociable, dissolution inhibiting group.
Hereinafter, preferred embodiments of the component (A-1) and the component (A-2) will be described more specifically.

[(A-1) component]
Examples of the component (A-1) include a resin in which a part or all of the alkali-soluble group in the resin having an alkali-soluble group (hydroxyl group, carboxy group, etc.) is protected with an acid dissociable, dissolution inhibiting group. In such a resin component, when the acidic group acts, the acid dissociable, dissolution inhibiting group of the resin component is dissociated, and the alkali-soluble group is exposed to increase the alkali solubility.
Examples of the resin having an alkali-soluble group include a novolak resin, a polyhydroxystyrene (PHS) resin (polyhydroxystyrene, hydroxystyrene-styrene copolymer, etc.) having a structural unit derived from hydroxystyrene, and an acrylic ester. An acrylic resin having a structural unit derived from, a polycycloolefin (PCO) resin having a structural unit derived from cycloolefin, and the like. Among these, a PHS resin and / or an acrylic resin are preferable. .
That is, as the component (A-1), an acrylic resin having an acid dissociable, dissolution inhibiting group (hereinafter referred to as resin (A-11)) or a PHS resin having an acid dissociable, dissolution inhibiting group (hereinafter, referred to as “resin”). Resin (A-12)) is preferable.

Here, in the present specification and claims, the “structural unit derived from hydroxystyrene” means a structural unit formed by cleavage of an ethylenic double bond of hydroxystyrene.
“Hydroxystyrene” is a concept including hydroxystyrene in a narrow sense and those in which a substituent (atom or group other than a hydrogen atom) is bonded to the α-position carbon atom in the α-position of narrowly defined hydroxystyrene. Examples of the substituent include a lower alkyl group and a halogenated lower alkyl group. Examples of the halogen atom in the halogenated lower alkyl group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The term “α-position (α-position carbon atom) of hydroxystyrene” refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.
Specific examples of the lower alkyl group as a substituent at the α-position in hydroxystyrene include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, and isopentyl. And a lower linear or branched alkyl group such as a neopentyl group.
In the present invention, the α-position of hydroxystyrene is preferably a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, more preferably a hydrogen atom or a lower alkyl group. In view of easy availability, a hydrogen atom or a methyl group is most preferable.

In the present specification and claims, the “structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid esters” include those in which a hydrogen atom is bonded to the carbon atom at the α-position, and those in which a substituent (atom or group other than a hydrogen atom) is bonded to the carbon atom in the α-position. Include concepts. Examples of the substituent include a lower alkyl group and a halogenated lower alkyl group. Examples of the halogen atom in the halogenated lower alkyl group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In the acrylate ester, as the lower alkyl group as a substituent at the α-position, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, Examples include lower linear or branched alkyl groups such as isopentyl group and neopentyl group.
In the present invention, the α-position of the acrylate ester is preferably a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, more preferably a hydrogen atom or a lower alkyl group. From the above availability, a hydrogen atom or a methyl group is most preferable.

[Resin (A-11)]
Examples of the resin (A-11) include a resin (A1) having a structural unit (a1) derived from an acrylate ester having an acid dissociable, dissolution inhibiting group.
The acid dissociable, dissolution inhibiting group in the structural unit (a1) has an alkali dissolution inhibiting property that makes the entire resin (A1) insoluble in alkali before dissociation, and changes the entire resin (A1) to alkali soluble after dissociation. If it is a thing, the thing proposed so far as an acid dissociable, dissolution inhibiting group of the base resin for chemically amplified resists can be used. Generally, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in (meth) acrylic acid or the like; an acetal-type acid dissociable, dissolution inhibiting group such as an alkoxyalkyl group is widely known. .

Here, the “tertiary alkyl ester” is an ester formed by replacing a hydrogen atom of a carboxy group with a chain or cyclic alkyl group, and the carbonyloxy group (—C (O)). A structure in which the tertiary carbon atom of the chain or cyclic alkyl group is bonded to the terminal oxygen atom of -O-). In this tertiary alkyl ester, when the acid generated from the component (B) acts, the bond is broken between the oxygen atom and the tertiary carbon atom.
The chain or cyclic alkyl group may have a substituent.
Hereinafter, a group that is acid dissociable by constituting a carboxy group and a tertiary alkyl ester is referred to as a “tertiary alkyl ester type acid dissociable, dissolution inhibiting group” for convenience.
Examples of the tertiary alkyl ester type acid dissociable, dissolution inhibiting group include an aliphatic branched acid dissociable, dissolution inhibiting group and an acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group.

Here, in the claims and the specification, “aliphatic branched” means having a branched structure having no aromaticity.
The structure of the aliphatic branched acid dissociable, dissolution inhibiting group is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The hydrocarbon group may be either saturated or unsaturated, but is usually preferably saturated.
As the aliphatic branched acid dissociable, dissolution inhibiting group, a tertiary alkyl group having 4 to 8 carbon atoms is preferable, and specific examples include a tert-butyl group, a tert-pentyl group, and a tert-heptyl group. .

The “aliphatic cyclic group” means a monocyclic group or a polycyclic group having no aromaticity.
The “aliphatic cyclic group” in the structural unit (a1) may or may not have a substituent. Examples of the substituent include a lower alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= O), and the like.
The basic ring structure excluding the substituent of the “aliphatic cyclic group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated. The “aliphatic cyclic group” is preferably a polycyclic group.
Specific examples of the aliphatic cyclic group include, for example, a monocycloalkane, a bicycloalkane, a tricycloalkane, which may or may not be substituted with a lower alkyl group, a fluorine atom or a fluorinated alkyl group, Examples thereof include a group obtained by removing one or more hydrogen atoms from a polycycloalkane such as tetracycloalkane. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Examples of the acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group include a group having a tertiary carbon atom on the ring skeleton of a cyclic alkyl group. Specifically, 2-methyl-2 -Adamantyl group, 2-ethyl-2-adamantyl group, etc. are mentioned. Alternatively, in the structural units represented by the following general formulas (a1 ″ -1) to (a1 ″ -6), an adamantyl group such as a group bonded to an oxygen atom of a carbonyloxy group (—C (O) —O—) An aliphatic cyclic group such as a cyclohexyl group, a cyclopentyl group, a norbornyl group, a tricyclodecanyl group, or a tetracyclododecanyl group, and a branched alkylene group having a tertiary carbon atom bonded thereto. Groups.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｒ^１５、Ｒ^１６はアルキル基（直鎖状、分岐鎖状のいずれでもよく、好ましくは炭素数１〜５である）を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ¹⁵ and R ^{16 each} represents an alkyl group (which may be linear or branched, and preferably has 1 to 5 carbon atoms. Is). ]

  In the general formulas (a1 ″ -1) to (a1 ″ -6), the lower alkyl group or halogenated lower alkyl group of R is a lower alkyl group or halogenated lower alkyl which may be bonded to the α-position of the acrylate ester. It is the same as the alkyl group.

The “acetal-type acid dissociable, dissolution inhibiting group” is generally bonded to an oxygen atom by substituting a hydrogen atom at the terminal of an alkali-soluble group such as a carboxy group or a hydroxyl group. When an acid is generated by exposure, the acid acts to break the bond between the acetal acid dissociable, dissolution inhibiting group and the oxygen atom to which the acetal acid dissociable, dissolution inhibiting group is bonded.
Examples of the acetal type acid dissociable, dissolution inhibiting group include a group represented by the following general formula (p1).

［式中、Ｒ^１’，Ｒ^２’はそれぞれ独立して水素原子または低級アルキル基を表し、ｎは０〜３の整数を表し、Ｙは低級アルキル基または脂肪族環式基を表す。］

[Wherein, R ^{1 ′} and R ^{2 ′} each independently represent a hydrogen atom or a lower alkyl group, n represents an integer of 0 to 3, and Y represents a lower alkyl group or an aliphatic cyclic group. ]

In the above formula, n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.
Examples of the lower alkyl group for R ^{1 ′} and R ^{2 ′} include the same lower alkyl groups as those described above for R. A methyl group or an ethyl group is preferable, and a methyl group is most preferable.
In the present invention, at least one of R ^{1 ′} and R ^{2 ′} is preferably a hydrogen atom. That is, the acid dissociable, dissolution inhibiting group (p1) is preferably a group represented by the following general formula (p1-1).

［式中、Ｒ^１’、ｎ、Ｙは上記と同様である。］

[Wherein, R ^{1 ′} , n and Y are the same as described above. ]

Examples of the lower alkyl group for Y include the same lower alkyl groups as those described above for R.
The aliphatic cyclic group for Y can be appropriately selected from monocyclic or polycyclic aliphatic cyclic groups conventionally proposed in a number of ArF resists and the like. For example, the above “aliphatic ring” Examples thereof are the same as those in the formula group.

  Examples of the acetal type acid dissociable, dissolution inhibiting group also include a group represented by the following general formula (p2).

［式中、Ｒ^１７、Ｒ^１８はそれぞれ独立して直鎖状または分岐鎖状のアルキル基または水素原子であり、Ｒ^１９は直鎖状、分岐鎖状または環状のアルキル基である。または、Ｒ^１７およびＲ^１９がそれぞれ独立に直鎖状または分岐鎖状のアルキレン基であって、Ｒ^１７の末端とＲ^１９の末端とが結合して環を形成していてもよい。］

[Wherein, R ¹⁷ and R ¹⁸ each independently represent a linear or branched alkyl group or a hydrogen atom, and R ¹⁹ represents a linear, branched or cyclic alkyl group. Alternatively, R ¹⁷ and R ¹⁹ may be each independently a linear or branched alkylene group, and the end of R ^{17 and} the end of R ¹⁹ may be bonded to form a ring. ]

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group. In particular, it is preferable that one of R ¹⁷ and R ¹⁸ is a hydrogen atom and the other is a methyl group.
R ¹⁹ is a linear, branched or cyclic alkyl group, preferably having 1 to 15 carbon atoms, and may be any of linear, branched or cyclic.
When R ¹⁹ is linear or branched, it preferably has 1 to 5 carbon atoms, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.
When R ¹⁹ is cyclic, it preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, one or more polycycloalkanes such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group, are included. Examples include groups excluding hydrogen atoms. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
In the above formula, R ¹⁷ and R ¹⁹ are each independently a linear or branched alkylene group (preferably an alkylene group having 1 to 5 carbon atoms), and the end of R ^{19 and} the end of R ¹⁷ And may be combined.
In this case, a cyclic group is formed by R ¹⁷ , R ¹⁹ , the oxygen atom to which R ¹⁹ is bonded, and the carbon atom to which the oxygen atom and R ¹⁷ are bonded. The cyclic group is preferably a 4-7 membered ring, and more preferably a 4-6 membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

  As the structural unit (a1), one or more selected from the group consisting of structural units represented by the following general formula (a1-0-1) and structural units represented by the following general formula (a1-0-2): Is preferably used.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^１は酸解離性溶解抑制基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; and X ¹ represents an acid dissociable, dissolution inhibiting group. ]

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^２は酸解離性溶解抑制基を示し；Ｙ^２はアルキレン基または脂肪族環式基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; X ² represents an acid dissociable, dissolution inhibiting group; Y ² represents an alkylene group or an aliphatic cyclic group. ]

In general formula (a1-0-1), the lower alkyl group or halogenated lower alkyl group for R is the same as the lower alkyl group or halogenated lower alkyl group that may be bonded to the α-position of the acrylate ester. .
X ¹ is not particularly limited as long as it is an acid dissociable, dissolution inhibiting group, and examples thereof include the above-described tertiary alkyl ester type acid dissociable, dissolution inhibiting group and acetal type acid dissociable, dissolution inhibiting group. A tertiary alkyl ester type acid dissociable, dissolution inhibiting group is preferred.

In general formula (a1-0-2), R is the same as defined above.
X ² is the same as X ¹ in formula (a1-0-1).
Y ² is preferably an alkylene group having 1 to 4 carbon atoms or a divalent aliphatic cyclic group, and the aliphatic cyclic group is the above except that a group in which two or more hydrogen atoms are removed is used. The thing similar to description of an "aliphatic cyclic group" can be used.

  More specifically, examples of the structural unit (a1) include structural units represented by the following general formulas (a1-1) to (a1-4).

［上記式中、Ｘ’は第３級アルキルエステル型酸解離性溶解抑制基を表し、Ｙは炭素数１〜５の低級アルキル基、または脂肪族環式基を表し；ｎは０〜３の整数を表し；ｍは０または１を表し；Ｒは前記と同じであり、Ｒ^１’、Ｒ^２’はそれぞれ独立して水素原子または炭素数１〜５の低級アルキル基を表す。］

[In the above formula, X ′ represents a tertiary alkyl ester type acid dissociable, dissolution inhibiting group, Y represents a lower alkyl group having 1 to 5 carbon atoms, or an aliphatic cyclic group; M represents 0 or 1; R is the same as defined above; R ¹ ′ and R ² ′ each independently represent a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms. ]

At least one of R ¹ ′ and R ² ′ is preferably a hydrogen atom, more preferably a hydrogen atom. n is preferably 0 or 1.
X ′ is the same as the tertiary alkyl ester type acid dissociable, dissolution inhibiting group exemplified in X ¹ above.
Examples of the aliphatic cyclic group for Y include the same groups as those exemplified above in the description of “aliphatic cyclic group”.

  Specific examples of the structural units represented by the general formulas (a1-1) to (a1-4) are shown below.

As the structural unit (a1), one type may be used alone, or two or more types may be used in combination.
As the structural unit (a1), a structural unit derived from an acrylate ester having an acetal-type acid dissociable, dissolution inhibiting group is preferable, and a structural unit represented by the general formula (a1-2) is more preferable. Among these, it is preferable to use at least one selected from structural units represented by (a1-232) to (a1-239).
Moreover, as the structural unit (a1), those represented by the following general formula (a1-1-01) including the structural units of the formulas (a1-1-1) to (a1-1-4), The following general formula (a1-1-02) including the structural units of the formulas (a1-1-35) to (a1-1-41) is also preferable.

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１１は低級アルキル基を示す。）

(In the formula, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹¹ represents a lower alkyl group.)

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１２は低級アルキル基を示す。ｈは１〜３の整数を表す）

(Wherein R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ¹² represents a lower alkyl group, and h represents an integer of 1 to 3).

In general formula (a1-1-01), R is the same as defined above. The lower alkyl group for R ^{11 is the same as} the lower alkyl group for R, and is preferably a methyl group or an ethyl group.
In general formula (a1-1-02), R is the same as defined above. The lower alkyl group for R ^{12 is the same as} the lower alkyl group for R, preferably a methyl group or an ethyl group, and most preferably an ethyl group. h is preferably 1 or 2, and most preferably 2.

  In the resin (A1) component, the proportion of the structural unit (a1) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, more preferably 25 to 50 mol, based on all structural units constituting the resin (A1). % Is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when the resist composition is used, and by setting it to the upper limit value or less, it is possible to balance with other structural units.

Structural unit (a2):
In addition to the structural unit (a1), the resin (A1) preferably further has a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group.
Here, the lactone-containing cyclic group refers to a cyclic group containing one ring (lactone ring) containing an —O—C (O) — structure as described above. The lactone ring is counted as the first ring. When only the lactone ring is present, it is called a monocyclic group. When it has another ring structure, it is called a polycyclic group regardless of the structure.
When the resin (A1) is used for forming a resist film, the lactone cyclic group of the structural unit (a2) increases the adhesion of the resist film to the substrate or has an affinity for a developer containing water. It is effective in raising.

As the structural unit (a2), any unit can be used without any particular limitation.
Specifically, examples of the lactone-containing monocyclic group include groups in which one hydrogen atom has been removed from γ-butyrolactone. Examples of the lactone-containing polycyclic group include groups in which one hydrogen atom has been removed from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring.

  More specifically, examples of the structural unit (a2) include structural units represented by general formulas (a2-1) to (a2-5) shown below.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基であり、Ｒ’は水素原子、低級アルキル基、または炭素数１〜５のアルコキシ基であり、ｍは０または１の整数であり、Ａは炭素数１〜５のアルキレン基または酸素原子である。］

[Wherein, R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ′ is a hydrogen atom, a lower alkyl group, or an alkoxy group having 1 to 5 carbon atoms, and m is an integer of 0 or 1. And A is an alkylene group having 1 to 5 carbon atoms or an oxygen atom. ]

R in the general formulas (a2-1) to (a2-5) is the same as R in the structural unit (a1).
The lower alkyl group for R ′ is the same as the lower alkyl group for R in the structural unit (a1).
Specific examples of the alkylene group having 1 to 5 carbon atoms of A include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.
In general formulas (a2-1) to (a2-5), R ′ is preferably a hydrogen atom in view of industrial availability.
Below, the specific structural unit of the said general formula (a2-1)-(a2-5) is illustrated.

  Among these, it is preferable to use at least one selected from general formulas (a2-1) to (a2-5), and at least one selected from general formulas (a2-1) to (a2-3). It is preferable to use more than one species. Specifically, chemical formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-2), (a2-3-1), (a2-3) -2), at least one selected from (a2-3-9) and (a2-3-10) is preferably used.

In the resin (A1), as the structural unit (a2), one type of structural unit may be used alone, or two or more types may be used in combination.
The proportion of the structural unit (a2) in the resin (A1) is preferably from 5 to 60 mol%, more preferably from 10 to 60 mol%, based on the total of all structural units constituting the resin (A1). 55 mol% is more preferable. By making it the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by making it the upper limit value or less, it is possible to balance with other structural units.

-Structural unit (a3):
The resin (A1) is derived from an acrylic ester containing a polar group-containing aliphatic hydrocarbon group in addition to the structural unit (a1) or in addition to the structural unit (a1) and the structural unit (a2). It is preferable to have a structural unit (a3). By having the structural unit (a3), the hydrophilicity of the resin (A1) is increased, the affinity with the developer is increased, the alkali solubility in the exposed area is improved, and the resolution is improved.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyfluoroalkyl group (a hydroxyalkyl group in which some or all of the hydrogen atoms bonded to a carbon atom are substituted with a fluorine atom). 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) and a polycyclic aliphatic hydrocarbon group (polycyclic group). . As the polycyclic group, for example, a resin for a resist composition for ArF excimer laser can be appropriately selected from among many proposed ones. The polycyclic group preferably has 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxyl group, a cyano group, a carboxy group, or an alkyl group is substituted with a fluorine atom Is more preferable. Examples of the polycyclic group include groups in which one or more hydrogen atoms have been removed from bicycloalkane, tricycloalkane, tetracycloalkane, or the like. Specific examples include groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Among these polycyclic groups, there are 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. Industrially preferable.

  The structural unit (a3) is derived from a hydroxyethyl ester of acrylic acid 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. When the hydrocarbon group is a polycyclic group, a structural unit represented by the following formula (a3-1), a structural unit represented by (a3-2), (a3-3) The structural unit represented by is mentioned as a preferable thing.

（式中、Ｒは前記と同じであり、ｊは１〜３の整数であり、ｋは１〜３の整数であり、ｔ’は１〜３の整数であり、ｌは１〜５の整数であり、ｓは１〜３の整数である。）

(Wherein R is the same as 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, and l is an integer of 1 to 5) And s is an integer of 1 to 3.)

In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.
j is preferably 1, and a hydroxyl group bonded to the 3-position of the adamantyl group is particularly preferred.
In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.
In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. These preferably have a 2-norbornyl group or a 3-norbornyl group bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5th or 6th position of the norbornyl group.

As the structural unit (a3), one type may be used alone, or two or more types may be used in combination.
As the structural unit (a3), a structural unit represented by the formula (a3-1) is particularly preferable.
In the resin (A1), the proportion of the structural unit (a3) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, based on all structural units constituting the resin (A1). More preferred is ˜25 mol%.

Structural unit (a4):
The resin (A1) may contain other structural units (a4) other than the structural units (a1) to (a3) as long as the effects of the present invention are not impaired.
The structural unit (a4) is not particularly limited as long as it is another structural unit that is not classified into the structural units (a1) to (a3) described above. For ArF excimer laser, for KrF excimer laser (preferably ArF excimer laser) A number of conventionally known resins can be used for resist resins such as
As the structural unit (a4), for example, a structural unit derived from an acrylate ester containing a non-acid-dissociable aliphatic polycyclic group is preferable. Examples of the polycyclic group include those exemplified in the case of the structural unit (a1), and for ArF excimer laser and KrF excimer laser (preferably for ArF excimer laser). A number of hitherto known materials can be used for the resin component of the resist composition.
In particular, at least one selected from a tricyclodecanyl group, an adamantyl group, a tetracyclododecanyl group, an isobornyl group, and a norbornyl group is preferable in terms of industrial availability. 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 those represented by the following general formulas (a4-1) to (a4-5).

（式中、Ｒは前記と同じである。）

(In the formula, R is as defined above.)

  When the structural unit (a4) is contained in the resin (A1), the structural unit (a4) is contained in an amount of 1 to 30 mol%, preferably 10 to 10% with respect to the total of all the structural units constituting the resin (A1). It is preferable to contain 20 mol%.

  In the present invention, the resin (A1) is preferably a copolymer having the structural units (a1), (a2) and (a3). Examples of such a copolymer include a copolymer composed of the structural units (a1), (a2) and (a3), and a copolymer composed of the structural units (a1), (a2), (a3) and (a4). A polymer etc. can be illustrated.

The resin (A1) can be obtained by polymerizing a monomer for deriving each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).
In addition, the resin (A1) is used in combination with a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH at the time of the above-described polymerization. A —C (CF ₃ ) ₂ —OH group may be introduced into the. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing

The mass average molecular weight (Mw) of the resin (A1) (polystyrene conversion standard by gel permeation chromatography) is not particularly limited, but is preferably 2000 to 50000, more preferably 3000 to 30000, and most preferably 5000 to 20000. preferable. When it is smaller than the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is larger than the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
The dispersity (Mw / Mn) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and still more preferably 1.2 to 2.5. In addition, Mn shows a number average molecular weight.

[Resin (A-12)]
Examples of the resin (A-12) include a resin (A2) having a structural unit (a5) in which a hydrogen atom of a hydroxyl group in a structural unit derived from hydroxystyrene is substituted with an acid dissociable, dissolution inhibiting group-containing group. Can be mentioned.
The acid dissociable, dissolution inhibiting group-containing group in the structural unit (a5) may be the acid dissociable, dissolution inhibiting group itself, and the acid dissociable, dissolution inhibiting group and other groups and / or atoms in the structure thereof. It may be a containing group.

As the acid dissociable, dissolution inhibiting group for the structural unit (a5), the same groups as those described above for the structural unit (a1) can be used. In addition, in the structural unit (a5), in addition to them, a chain tertiary alkoxycarbonyl group, a chain tertiary alkoxycarbonylalkyl group, and the like are also preferably used.
The chain tertiary alkyl group in the chain tertiary alkyloxycarbonyl group preferably has 4 to 10 carbon atoms, and more preferably 4 to 8 carbon atoms. Specific examples of the chain-like tertiary alkyloxycarbonyl group include a tert-butoxycarbonyl group and a tert-pentyloxycarbonyl group.
Examples of the chain tertiary alkyl group in the chain tertiary alkoxycarbonylalkyl group include the same groups as those described above. 1-5 are preferable and, as for carbon number of the alkyl group (alkylene group) which the chain | strand-shaped tertiary alkoxycarbonyl group couple | bonded, 1-4 are more preferable. Specific examples of the chain-like tertiary alkoxycarbonylalkyl group include a tert-butoxycarbonylmethyl group, a tert-pentyloxycarbonylmethyl group, and the like.

Examples of the group containing an acid dissociable, dissolution inhibiting group and other group and / or atom in the structure include a group represented by the following general formula (p′1). In the group having such a structure, when an acidic group is formed in the polymer compound (A1) by exposure, an oxygen atom bonded to Y ′ is bonded to R ¹³ and R ¹⁴ by the action of the acidic group. The bond between the carbon atoms is broken, and -C (R ¹³ ) (R ¹⁴ ) -OY is dissociated.

［式中、Ｙ’は脂肪族環式基、芳香族環式炭化水素基または低級アルキル基を表し、Ｒ^１３は水素原子または低級アルキル基を表す。または、Ｙ’およびＲ^１３がそれぞれ独立に炭素数１〜５のアルキレン基であってＹ’の末端とＲ^１３の末端とが結合していてもよい。Ｒ^１４は低級アルキル基または水素原子を表し、Ａ’は脂肪族環式基を表す。］

[Wherein Y ′ represents an aliphatic cyclic group, an aromatic cyclic hydrocarbon group or a lower alkyl group, and R ¹³ represents a hydrogen atom or a lower alkyl group. Alternatively, Y ′ and R ¹³ may each independently be an alkylene group having 1 to 5 carbon atoms, and the end of Y ′ may be bonded to the end of R ¹³ . R ¹⁴ represents a lower alkyl group or a hydrogen atom, and A ′ represents an aliphatic cyclic group. ]

Examples of the aliphatic cyclic group for Y ′ include the same aliphatic cyclic groups as those described above for the Y aliphatic cyclic group of the above formula (p1).
Examples of the aromatic cyclic hydrocarbon group for Y ′ include an aromatic polycyclic group having 10 to 16 carbon atoms. Specific examples include groups in which one hydrogen atom has been removed from naphthalene, anthracene, phenanthrene, pyrene, and the like. Specific examples include 1-naphthyl group, 2-naphthyl group, 1-anthracenyl group, 2-anthracenyl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 1-pyrenyl group, and the like. A naphthyl group is particularly preferred industrially.
The lower alkyl group for Y ′ is more preferably a methyl group or an ethyl group, and most preferably an ethyl group.
Examples of the aliphatic cyclic group for A ′ include a group obtained by removing one hydrogen atom from the aliphatic cyclic group for Y ′.

  Examples of the structural unit (a5) include structural units represented by the following general formula (a5-1).

［上記式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を表し；Ｘ^３は酸解離性溶解抑制基含有基を表し；Ｒ^５は低級アルキル基を表し；ｎ１１は１〜３の整数を表し；ｎ１２は０〜２の整数を表す。］

[In the above formula, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; X ³ represents an acid dissociable, dissolution inhibiting group-containing group; R ⁵ represents a lower alkyl group; N12 represents an integer of 0-2. ]

In general formula (a5-1), R is as defined above, and is preferably a hydrogen atom or a methyl group.
The group containing an acid dissociable, dissolution inhibiting group for X ³ is the same as described above.
n11 is an integer of 1 to 3, preferably 1.
When n11 is 1, the hydroxyl substitution position may be any of the o-position, m-position, and p-position, but the p-position is preferred because it is readily available and inexpensive. Furthermore, when n11 is 2 or 3, arbitrary substitution positions can be combined.

n12 is an integer of 0 to 2, preferably 0 or 1, and industrially particularly preferably 0.
Examples of the lower alkyl group for R ⁵ include the same as the lower alkyl group for R ⁵ .
The substitution position of R ⁵ may be any of o-position, m-position and p-position when n12 is 1, and when n12 is 2, any substitution position may be combined. it can.

The structural unit (a5) can be used alone or in combination of two or more.
In the resin (A2), the proportion of the structural unit (a ″ 5) is preferably 10 to 90 mol% and more preferably 50 to 80 mol% with respect to all the structural units constituting the resin (A ″ 2). Preferably, 60-80 mol% is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when the resist composition is used, and by setting it to the upper limit value or less, it is possible to balance with other structural units.

-Structural unit (a6):
The resin (A2) preferably further has a structural unit (a6) derived from hydroxystyrene in addition to the structural unit (a5). By having the structural unit (a6), the hydrophilicity of the resin (A2) is increased, the affinity with the developer is increased, the alkali solubility in the exposed area is improved, and the resolution is improved.
As a structural unit (a6), the structural unit represented by the following general formula (a6-1) can be illustrated, for example.

［上記式中、Ｒは水素原子、炭素数１〜５の低級アルキル基またはハロゲン化低級アルキル基を表し；Ｒ^６は炭素数１〜５の低級アルキル基を表し；ｎ１３は１〜３の整数を表し；ｎ１４は０〜２の整数を表す。］

[In the above formula, R represents a hydrogen atom, a lower alkyl group having 1 to 5 carbon atoms or a halogenated lower alkyl group; R ⁶ represents a lower alkyl group having 1 to 5 carbon atoms; n13 is an integer of 1 to 3] N14 represents an integer of 0 to 2; ]

In general formula (a6-1), R, R ⁶ , n13 and n14 are the same as R, R ⁵ , n11 and n12 in formula (a5-1), respectively.

The structural unit (a6) can be used alone or in combination of two or more.
In the resin (A2), the proportion of the structural unit (a6) is preferably 10 to 95 mol%, more preferably 20 to 85 mol%, based on all the structural units constituting the resin (A2). 80 mol% is more preferable and 60-70 mol% is especially preferable. Within this range, moderate alkali solubility can be obtained and the balance with other structural units is good.

-Structural unit (a7):
The resin (A2) may further have a structural unit (a7) derived from styrene. By incorporating the structural unit (a7) into the resin (A2) and adjusting its content, the solubility of the resin (A2) in an alkaline developer can be adjusted, thereby controlling the alkali solubility of the resist film. , The shape can be further improved.
Here, “structural unit derived from styrene” means a structural unit formed by cleavage of an ethylenic double bond of styrene. “Styrene” is a concept including styrene in a narrow sense, and those in which a hydrogen atom at the α-position of styrene in a narrow sense is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. In styrene, the hydrogen atom of the phenyl group may be substituted with a substituent such as a lower alkyl group.
Examples of the structural unit (a7) include structural units represented by the following general formula (a7-1).

［式中、Ｒは水素原子、炭素数１〜５の低級アルキル基またはハロゲン化低級アルキル基を表し；Ｒ^７は炭素数１〜５の低級アルキル基を表し；ｎ１５は０〜３の整数を表す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group having 1 to 5 carbon atoms or a halogenated lower alkyl group; R ⁷ represents a lower alkyl group having 1 to 5 carbon atoms; and n15 represents an integer of 0 to 3] To express. ]

In formula (a7-1), examples of R and R ⁷ include the same as R and R ⁵ in formula (a5-1).
n15 is an integer of 0 to 3, preferably 0 or 1, and industrially particularly preferably 0.
The substitution position of R ⁷ may be any of o-position, m-position and p-position when n15 is 1, and any substitution position can be combined when n15 is 2 or 3.

As the structural unit (a7), one type may be used alone, or two or more types may be used in combination.
In the resin (A2), the proportion of the structural unit (a7) is preferably 1 to 20 mol%, more preferably 3 to 15 mol%, and more preferably 5 to 15 mol% with respect to all the structural units constituting the resin (A2). Is particularly preferred. Within this range, the effect of having the structural unit (a7) is high, and the balance with other structural units is also good.

・ Other structural units:
The resin (A2) may contain other structural units other than the structural units (a5) to (a7) as long as the effects of the present invention are not impaired. The other structural units are not particularly limited as long as they are other structural units not classified in the structural units (a5) to (a7), and are not limited to ArF excimer lasers and KrF positive excimer lasers (preferably ArF excimers). A number of hitherto known materials can be used for resist resins such as laser), and examples thereof include the structural units (a1) to (a4) mentioned in the resin (A1).

  The resin (A2) can be obtained by polymerizing a monomer for deriving each structural unit by a conventional method such as a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). it can.

The resin (A2) preferably has a mass average molecular weight (Mw; converted to polystyrene by gel permeation chromatography (GPC)) in the range of 2000 to 50000, more preferably 3000 to 30000, and more preferably 5000 to 20000. preferable. When Mw is not more than the upper limit of the above range, sufficient solubility in the resist solvent can be secured, and the surface roughness of the resist pattern can be reduced. Moreover, it is easy to adjust the solubility with respect to a developing solution as it is more than a lower limit. In addition, dry etching resistance is improved and film loss is improved.
The smaller the degree of dispersion (Mw / Mn (number average molecular weight)) of the resin (A2) (the closer to monodispersion), the better the resolution and the better. The degree of dispersion is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5.

[(A-2) component]
The component (A-2) has a molecular weight of 500 or more and 2000 or less, has a hydrophilic group, and has an acid dissociable, dissolution inhibiting group X or X as exemplified in the description of the component (A-1). Low molecular weight compounds having 'are preferred. Specific examples include those obtained by substituting a part of the hydrogen atoms of the hydroxyl group of the compound having a plurality of phenol skeletons with the acid dissociable, dissolution inhibiting group X or X ′.
The component (A-2) contains, for example, a part of the hydrogen atom of the hydroxyl group of a low molecular weight phenol compound known as a sensitizer or heat resistance improver for non-chemically amplified g-line or i-line resists. Those substituted with a dissociable, dissolution inhibiting group are preferred and can be arbitrarily used.
Examples of such low molecular weight phenol compounds include the following.
Bis (4-hydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl) propane, 2- (2,3,3) 4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-trihydroxyphenyl) propane, tris (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dimethylphenyl) -2- Hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4- Hydroxy-2,5-dimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4-hydroxy-3-methylphenol) Nyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -3 , 4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene, phenol, m-cresol, p-cresol or xylenol And 2,3,4 nuclei of formalin condensates of phenols and the like. Of course, it is not limited to these.
The acid dissociable, dissolution inhibiting group is not particularly limited, and examples thereof include those described above.

  The content of the component (A) in the resist composition is not particularly limited, and may be adjusted according to the resist film thickness to be formed. Usually, the higher the concentration of the component (A) in the organic solvent solution of the resist composition, the thicker the resist film formed.

<Optional component>
The resist composition may further contain a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) as an optional component in order to improve the resist pattern shape, the stability over time, and the like. preferable.
Since a wide variety of components (D) have already been proposed, any known one may be used, but cyclic amines, aliphatic amines, particularly secondary aliphatic amines and tertiary fats may be used. Group amines are preferred. Here, the aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include amines (alkyl amines or alkyl alcohol amines) in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms. Specific examples thereof include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di-n-heptylamine, Dialkylamines such as di-n-octylamine and dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-hexylamine, tri-n-pentylamine, tri-n-heptyl Trialkylamines such as amine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, tri-n-dodecylamine; diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n -Ok Noruamin, alkyl alcohol amines such as tri -n- octanol amine.
Among these, alkyl alcohol amines and trialkyl amines are preferable, and alkyl alcohol amines are most preferable. Of the alkyl alcohol amines, triethanolamine and triisopropanolamine are most preferred.
Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 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.
Any of these components (D) may be used alone or in combination of two or more.
(D) component is normally used in the ratio of 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

The resist composition is selected from the group consisting of organic carboxylic acids, phosphorus oxoacids and derivatives thereof as optional components for the purpose of preventing sensitivity deterioration, improving the resist pattern shape, stability over time, etc. At least one compound (E) (hereinafter referred to as component (E)).
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 phosphorus oxo acids and derivatives thereof include phosphoric acid, phosphonic acid, phosphinic acid and the like, and among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
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 the phosphinic acid derivatives include phosphinic acid esters such as phenylphosphinic acid.
(E) A component may be used individually by 1 type and may use 2 or more types together.
(E) A component is normally used in the ratio of 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

  The resist composition may further contain miscible additives as desired, for example, additional resins for improving the performance of the resist film, surfactants for improving coating properties, dissolution inhibitors, plasticizers, stabilizers. Further, a colorant, an antihalation agent, a dye and the like can be added and contained as appropriate.

<Organic solvent>
The resist composition can be produced by dissolving the material in an organic solvent (hereinafter sometimes referred to as (S) component).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution, and any one of conventionally known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone;
Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone;
Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol;
Compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl ether, monopropyl of the polyhydric alcohols or the compound having an ester bond Derivatives of polyhydric alcohols such as ethers, monoalkyl ethers such as monobutyl ether or compounds having an ether bond such as monophenyl ether [in these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) Is preferred];
Cyclic ethers such as dioxane and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate;
Aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. be able to.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Of these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The mixing ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, but is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3.
In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of component (S) used is not particularly limited, but it is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. -20% by mass, preferably 5-15% by mass.

<Resist pattern formation method>
The resist composition includes a step of forming a resist film on a support using the resist composition, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern. It is suitably used for the method. In the present specification, “exposure” is a concept including general irradiation of radiation.

In the resist pattern forming method, the support is not particularly limited, and a conventionally known one can be used. Examples thereof include a substrate for electronic parts and a substrate on which a predetermined wiring pattern is formed. can do. More specifically, a silicon substrate, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
In addition, the support may be a substrate in which an inorganic and / or organic film is provided on the above-described substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include an organic antireflection film (organic BARC).

The resist pattern forming method can be performed, for example, as follows.
That is, first, the resist composition is coated on a support with a spinner or the like, and pre-baked (post-apply bake (PAB)) for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of 80 to 150 ° C. Then, a resist film is formed. The resist film is selectively exposed using a predetermined exposure light source with or without a desired mask pattern. That is, exposure is performed through the mask pattern, or drawing is performed by direct irradiation with an electron beam without using the mask pattern.
After the selective exposure, heat treatment (post-exposure baking (PEB)) is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of 80 to 150 ° C. Subsequently, this is developed using an alkali developer, for example, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH), preferably rinsed with pure water and dried. A resist pattern can be formed.

The wavelength used for the exposure is not particularly limited, and includes KrF excimer laser, ArF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. Can be done using radiation. Among these, the resist composition is particularly effective for KrF excimer laser, ArF excimer laser, EB or EUV, particularly ArF excimer laser.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
[Synthesis Example 1 (Synthesis of Intermediate)]
(First step)
7.01 g of nonafluorobutyltrimethylsilane (C ₄ F ₉ SiMe ₃ ) and 3.13 g of 2-naphthaldehyde were dissolved in 6.6 ml of 1,2-dimethoxyethane (glyme). To this solution, 0.20 g of CsF was added in portions at room temperature with stirring. After further stirring for 2 hours, 6.6 ml of methanol was added and stirred for 1 hour. The reaction solution was concentrated under reduced pressure, and 13.2 ml of toluene and 6.6 ml of saturated brine were added to the residue, followed by stirring for 30 minutes and liquid separation. The toluene solution was washed with 6.6 ml of saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. Recrystallization from hexane yielded 5.61 g of α-nonafluorobutyl-2-naphthalenemethanol (corresponding to 74% of the theoretical value).

The instrumental analysis results of the obtained α-nonafluorobutyl-2-naphthalenemethanol are shown below.
Melting point (Mp): 82.4 ° C.
IR (KBr) (ν / cm ⁻¹ ): 3416 (ν OH), 1280 to 1100 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 2.64 (1H, broadcast, OH), 5.35 (1H, m, CH), 7.49 to 7.56 (3H, m, naphthyl), 7.83 to 7.92 (4H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, reference: CF ₃ COOH): δ (ppm) = − 128.0 to −125.5 (2F), −123.8 to −121.7 (2F), −126 , -125.7, -118.0, -119.0 (2F) -81.6 (3F).
MS: 421 (M-H + HCOOH) ^- .

(Second step)
α-Nonafluorobutyl-2-naphthalene methanol (5.59 g) and diphosphorus pentoxide (4.22 g) were suspended in dimethylformamide (DMF) (15 ml). To this solution, 4.95 g of dimethyl sulfoxide (DMSO) was added with stirring at room temperature. After further stirring for 2 hours, the mixture was cooled to 30 ° C. or lower. To the reaction solution, 75 ml of toluene and 75 ml of water were added, and the mixture was stirred for 30 minutes and then separated. The toluene solution was washed successively with 45 ml of 5% aqueous sodium hydrogen carbonate solution and 45 ml of saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to give a crude product of 2-naphthyl (nonafluorobutyl) ketone. 88 g was obtained. The crude product was used in the next reaction without purification.

The instrumental analysis results of the obtained 2-naphthyl (nonafluorobutyl) ketone (crude product) are shown below.
Boiling point (Bp): 130 ° C./5 mmHg.
IR (neat) (ν / cm ⁻¹ ): 1701 (ν C═O), 1300 to 1100 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 7.58 to 7.72 (2H, m, naphthyl), 7.88 to 8.08 (4H, m, naphthyl), 8.64 ( 1H, s, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, standard: CF ₃ COOH): δ (ppm) = − 125.8 (2F), −122.5 (2F), −113.0 (2F), −81.6 (3F).

(Third step)
The crude product 2-naphthyl (nonafluorobutyl) ketone (6.88 g) and hydroxylamine hydrochloride (1.35 g) were dissolved in methanol-modified ethanol (3.8 ml) and pyridine (15 ml). This solution was heated and stirred at an internal temperature of 95 ° C. for 3 hours. The reaction solution was concentrated under reduced pressure, and 15 ml of water and 45 ml of ethyl acetate were added to the residue and stirred for 30 minutes. The reaction mixture was separated, and the resulting ethyl acetate solution was washed successively with 15 ml of 1N hydrochloric acid twice and twice with 15 ml of saturated brine. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure to obtain 5.75 g of a crude product of 2-naphthyl (nonafluorobutyl) ketone oxime.

The instrumental analysis results of the obtained 2-naphthyl (nonafluorobutyl) ketone oxime (crude product) are shown below.
MS: 388 (M-H) ^- .
IR (KBr) ((nu) / cm < ^-1 >): 3277 ((nu) OH), 1300-1110 ((nu) CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 7.43 to 7.59 (3H, m, naphthyl), 7.84 to 7.96 (4H, m, naphthyl), 8.92 ( 1H, broadcast, OH).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, standard: CF ₃ COOH): δ (ppm) = − 126.9, −126.0 (0.68F, 1.32F), −121.5, −120.7 (1.34F, 0.66F), -110.7, -108.5 (1.34F, 0.66F), -81.6, -81.4 (3F).

It was confirmed by ¹⁹ F-NMR that 2-naphthyl (nonafluorobutyl) ketone oxime (crude product) was obtained as a mixture of two isomers (mixing ratio of about 2: 1). The ¹⁹ F-NMR chart is shown in FIG.
In addition, each isomer could be confirmed (Rf = 0.27, 0.36) in TLC analysis (plate: silica gel, developing solvent: ethyl acetate / hexane = 1/5).

(Isomer control process)
The obtained crude product was dissolved in 28 ml of methanol. To this solution, 0.42 g of 35% hydrochloric acid was added with stirring at room temperature. Further, the mixture was heated to reflux with stirring for 30 hours. In TLC analysis (plate: silica gel, developing solvent: ethyl acetate / hexane = 1/5), it was confirmed that the component of Rf = 0.27 was a trace amount, and then 14 ml of methanol and 14 ml of water were added to the reaction solution. By crystallizing, 4.58 g of 2-naphthyl (nonafluorobutyl) ketone oxime (corresponding to 79% of the theoretical value from 2-naphthaldehyde) was obtained.

The instrumental analysis results of the obtained 2-naphthyl (nonafluorobutyl) ketone oxime are shown below.
Mp: 142.4 ° C.
IR (KBr) ((nu) / cm < ^-1 >): 3276 ((nu) OH), 1290-1110 ((nu) CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 7.45 (1H, d, naphthyl), 7.51 to 7.60 (2H, m, naphthyl), 7.86 to 7.94 ( 4H, m, naphthyl) 8.57 (1H, s, OH).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, reference: CF ₃ COOH): δ (ppm) = − 126.0 (2F), −121.5 (2F), −110.7 (2F), −81.6 (3F).

It was confirmed by ¹⁹ F-NMR that 2-naphthyl (nonafluorobutyl) ketone oxime was obtained as a pure stereoisomer (isomer control product). The ¹⁹ F-NMR chart is shown in FIG.

[Synthesis Example 2 (Synthesis of Intermediate)]
67.5 ml of diglyme was added to 28.57 g of silver fluoride and cooled to -10 ° C or lower. To this, 40.55 g of tetrafluoro-1,2-oxathietane-2,2-dioxide was added dropwise over 1 hour or more, and then stirred at room temperature for 1 hour. The system was cooled again to -10 ° C or lower, and a solution of 51.33 g of 2-bromomethylnaphthalene in 55.5 ml of diglyme was added dropwise over 1 hour. After stirring the reaction solution at room temperature overnight, 254 ml of toluene was charged and the system was cooled to -5 ° C or lower. 127 ml of water was added dropwise at −5 ° C. or lower over 30 minutes, followed by stirring for 10 minutes. The insoluble material was filtered off with suction filtration, and the filtrate was separated. The obtained organic layer was washed with 43 ml of saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. 254 ml of hexane was added to the residue, the precipitated crystals were filtered off, and the filtrate was concentrated under reduced pressure. From the obtained residue, (2-naphthyl) methoxytetrafluoroethanesulfonyl fluoride was separated by silica gel column chromatography. When this was analyzed by gas chromatography, the purity was 94.6%. The yield was 38.04 g, corresponding to 49.6% of theory.

The instrumental analysis results of the obtained (2-naphthyl) methoxytetrafluoroethanesulfonyl fluoride are shown below. The ¹⁹ F-NMR chart is shown in FIG.
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 5.26 (2H, s, CH ₂ ), 7.42 to 7.53 (3H, m, naphthyl), 7.81 to 7.89 (4H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, standard: CF ₃ COOH): δ (ppm) = − 111.5 (2F), −83.6 (2F), 43.4 (1F).

[Example 1]
1.10 g of 2-naphthyl (nonafluorobutyl) ketone oxime (isomer control product) obtained in Synthesis Example 1 and 0.76 g of 4-dimethylaminopyridine (DMAP) were dissolved in 7 ml of acetone. This solution was cooled to an internal temperature of 20 ° C. or lower, and a solution of (2-naphthyl) methoxytetrafluoroethanesulfonyl fluoride (1.79 g) obtained in Synthesis Example 2 in acetone (1 ml) was added dropwise with stirring, followed by stirring for 1 hour. did. Further, 7 ml of methanol was added at an internal temperature of 20 ° C. or less, and the mixture was stirred for 1 hour. The reaction mixture was poured into 56 g of 10% brine with vigorous stirring, and extracted with twice 28 ml and 14 ml of ethyl acetate. The ethyl acetate solution was successively washed twice with 17 g of 1N hydrochloric acid, 17 g of 10% brine, 17 g of 5% aqueous sodium hydrogen carbonate solution and 17 g of saturated brine. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure. From the obtained residue, 2-naphthyl (nonafluorobutyl) ketone O- (2-naphthyl) methoxytetrafluoroethanesulfonyloxime was separated by silica gel column chromatography. When this was analyzed by HPLC, the purity was 97.6%. The yield was 0.80 g, corresponding to 40% of the theoretical value.

The instrumental analysis results of the obtained 2-naphthyl (nonafluorobutyl) ketone O- (2-naphthyl) methoxytetrafluoroethanesulfonyloxime are shown below. The ¹⁹ F-NMR chart is shown in FIG.
Melting point: 66.1 ° C.
Decomposition point: 152.5 ° C.
¹ H-NMR (DMSO-d ₆ , 300 MHz): δ (ppm) = 5.39 (2H, s, CH ₂ ), 7.38-8.16 (14H, m, naphthyl).
¹⁹ F-NMR (DMSO-d ₆ , 283 MHz, reference: CF ₃ COOH): δ (ppm) = − 126.0 (2F), −121.7 (2F), −111.0 (2F), −110 .9 (2F), -82.5 (2F), -81.8 (3F).

[Example 2]
1.95 g of 2-naphthyl (nonafluorobutyl) ketone oxime (isomer control product) obtained in Synthesis Example 1 and 1.35 g of 4-dimethylaminopyridine (DMAP) were dissolved in 12.5 ml of acetone. This solution was cooled to an internal temperature of 20 ° C. or lower, and 2.17 g of allyloxytetrafluoroethanesulfonyl fluoride was added dropwise thereto with stirring, followed by stirring for 1 hour. Further, 5 ml of methanol was added at an internal temperature of 20 ° C. or lower, and the mixture was stirred for 1 hour. The reaction mixture was poured into 100 g of 10% brine with vigorous stirring, and extracted twice with 50 ml and 25 ml of ethyl acetate. The ethyl acetate solution was successively washed twice with 60 g of 1N hydrochloric acid, 30 g of 10% brine, 30 g of 5% aqueous sodium hydrogen carbonate solution and 30 g of saturated brine. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure. 2-Naphthyl (nonafluorobutyl) 2 O-allyloxytetrafluoroethanesulfonyloxime was separated from the obtained residue by silica gel column chromatography. When this was analyzed by HPLC, the purity was 98.4%. The yield was 1.28 g, corresponding to 41.9% of theory.

The instrumental analysis results of the obtained 2-naphthyl (nonafluorobutyl) ketone O-allyloxytetrafluoroethanesulfonyloxime are shown below. The ¹⁹ F-NMR chart is shown in FIG.
Decomposition point: 189.4 ° C
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 4.52 (1H, m, CH ₂ ), 5.23 to 5.39 (2H, m, CH ₂ ), 5.78 to 5. 91 (1H, m, CH), 7.38 (1H, d, naphthyl), 7.57 to 7.67 (2H, m, naphthyl), 7.89 to 7.98 (4H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz, standard: CF ₃ COOH): δ (ppm) = − 125.8 (2F), −121.2 (2F), −110.5 (2F), −110.3 (2F), -83.9 (2F), -81.6 (3F).

[Reference Examples 1-2, Comparative Reference Example 1]
Each component shown in Table 1 was mixed and dissolved to prepare a positive resist composition.
In Table 1, the numerical values in [] indicate the amount (parts by mass). Moreover, the symbol in Table 1 shows the following, respectively.
(A) -1: A copolymer represented by the following chemical formula (A) -1 and having Mw = 10000 and Mw / Mn = 2.0.
(B) -1: 2-naphthyl (nonafluorobutyl) ketone O- (2-naphthyl) methoxytetrafluoroethanesulfonyloxime obtained in Synthesis Example 3.
(B) -2: 2-naphthyl (nonafluorobutyl) ketone O-allyloxytetrafluoroethanesulfonyloxime obtained in Synthesis Example 4.
(B) -3: Triphenylsulfonium nonafluorobutanesulfonate (D) -1: Triethanolamine.
(S) -1: PGMEA.

［式中、ｍ：ｎ：ｌ＝４０：２０：４０（モル比）］

[Wherein m: n: l = 40: 20: 40 (molar ratio)]

  In addition, 4.41 mass parts of (B) -1, 3.79 mass parts of (B) -2, and 3.5 mass parts of (B) -3 are equimolar amounts.

The following evaluation was performed using the resist compositions of Reference Examples 1 and 2 and Comparative Reference Example 1.
[Measurement of absorbance]
In Table 1 above, each of the resist compositions of Reference Examples 1 and 2 and Comparative Reference Example 1 prepared without adding the component (D) was applied onto a 1-inch quartz substrate using a spinner, and the temperature was 110 ° C. Was baked for 60 seconds to form a resist film having a thickness of 150 nm. Then, using a spectrophotometer “VUV200” manufactured by JASCO, the absorbance of the resist film per 100 nm thickness of the resist film within a wavelength range of 130 nm to 300 nm was determined. Table 2 shows the absorbance per 100 nm of film thickness at a wavelength of 193 nm.

  As is clear from the above results, the resist compositions of Reference Examples 1 and 2 were higher in transparency to light having a wavelength near 193 nm than that of Comparative Reference Example 1. Since the resist compositions of Reference Examples 1 and 2 and Comparative Reference Example 1 are exactly the same except for the type of acid generator, the transparency of (B) -1 and (B) -2 is (B) It was confirmed that it was higher than -3.

[ArF lithography evaluation]
By applying an organic antireflective coating composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) on an 8-inch silicon wafer using a spinner, baking on a hot plate at 205 ° C. for 60 seconds and drying. An organic antireflection film having a thickness of 82 nm was formed. The resist composition of Reference Example 1 or 2 is applied onto the antireflection film using a spinner, prebaked (PAB) at 120 ° C. for 60 seconds on a hot plate, and dried to form a film. A resist film having a thickness of 150 nm was formed.
Next, an ArF excimer laser (193 nm) was selectively irradiated through the mask pattern by an ArF exposure apparatus NSR-S302 (Nikon Corp .; NA (numerical aperture) = 0.60, 2/3 annular illumination). . Then, PEB treatment was performed at 120 ° C. for 60 seconds, and further developed with an aqueous 2.38 mass% tetramethylammonium hydroxide (TMAH) solution at 23 ° C. for 30 seconds, followed by washing with water for 30 seconds, and then at 100 ° C. for 60 seconds. A second post-bake (PDB) treatment was performed. The substrate was observed with a scanning electron microscope (SEM) to determine whether a pattern was formed.
As a result, even when any of the resist compositions of Reference Examples 1 and 2 was used, a line-and-space resist pattern having a line width of 120 nm and a pitch of 240 nm was formed. The sensitivity of this time (optimum exposure amount which the resist pattern is formed), the reference example 1 74.0mJ / cm ^2, Reference Example 2 was 96.0mJ / cm ^2.

¹⁹ F-NMR chart of 2-naphthylnonafluorobutyl ketone oxime (isomer mixture) obtained in the third step of Synthesis Example 1. ¹⁹ F-NMR chart of 2-naphthylnonafluorobutylketone oxime (isomer control product) obtained in the isomer control step of Synthesis Example 1. ¹⁹ F-NMR chart of (2-naphthyl) methoxytetrafluoroethanesulfonyl fluoride obtained in Synthesis Example 2. ¹⁹ F-NMR chart of 2-naphthyl (nonafluorobutyl) ketone O- (2-naphthyl) methoxytetrafluoroethanesulfonyloxime obtained in Example 1. ¹⁹ F-NMR chart of 2-naphthyl (nonafluorobutyl) ketone O-allyloxytetrafluoroethanesulfonyloxime obtained in Example 2.

Claims (4)

The compound represented by the following general formula (I).

[Wherein, R ¹ is an organic group excluding a (meth) acryloyl group; R ² is a linear or branched alkylene group having 1 to 5 carbon atoms or a fluorinated alkylene group; and R ³ is substituted. or unsubstituted phenyl group, a 1-naphthyl group or a 2-naphthyl group; R ⁴ is a fluorinated alkyl group of 1 to 5 carbon atoms. ] The compound according to claim 1, wherein R ³ is a substituted or unsubstituted 1-naphthyl group or 2-naphthyl group. The compound according to claim 1 or 2, wherein R ¹ is a substituted or unsubstituted alkyl group. The compound according to claim 3, wherein R ¹ is an alkyl group substituted with an unsaturated aliphatic hydrocarbon group or an aromatic hydrocarbon group.

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