JP2008163218A - Polymer compound, resist composition and method for forming resist pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new polymer compound and a resist composition and to provide a method for forming a resist pattern. <P>SOLUTION: The present invention provides a resist composition containing a unit (a0) represented by general formula (a0-1) [wherein R<SP>1</SP>is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R<SP>2</SP>is an alkylene group or a fluorinated alkylene group; R<SP>3</SP>is an aryl group which may have a substituent; R<SP>4</SP>is a halogenated alkyl group]. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a novel polymer compound, a resist composition, and a resist pattern forming method that can be used for lithography.

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 been rapidly progressing 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 a novel high molecular compound, a resist composition, and a resist pattern formation method.

In order to achieve the above object, the present invention employs the following configuration.
That is, the 1st aspect of this invention is a high molecular compound containing the structural unit (a0) represented by the following general formula (a0-1).

［式中、Ｒ^１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^２はアルキレン基またはフッ素化アルキレン基であり；Ｒ^３は置換基を有していてもよいアリール基であり；Ｒ^４はハロゲン化アルキル基である。］

[Wherein, R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ² represents an alkylene group or a fluorinated alkylene group; and R ³ represents an aryl group which may have a substituent. Yes; R ⁴ is a halogenated alkyl group. ]

The second aspect of the present invention is a resist composition containing a resin component (A) whose alkali solubility is changed by the action of an acid,
The resin component (A) contains a polymer compound (A1) containing a structural unit (a0) represented by the following general formula (a0-1).

［式中、Ｒ^１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^２はアルキレン基またはフッ素化アルキレン基であり；Ｒ^３は置換基を有していてもよいアリール基であり；Ｒ^４はハロゲン化アルキル基である。］

[Wherein, R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ² represents an alkylene group or a fluorinated alkylene group; and R ³ represents an aryl group which may have a substituent. Yes; R ⁴ is a halogenated alkyl group. ]

  In a third aspect of the present invention, a resist pattern is formed on a support using the resist composition of the second aspect, the resist film is exposed, and the resist film is developed to form a resist pattern. It is a resist pattern formation method including the process of forming.

In the present specification and claims, the “structural unit” means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
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.
“Exposure” is a concept that includes radiation exposure in general.

  According to the present invention, a novel polymer compound, resist composition, and resist pattern forming method can be provided.

≪Polymer compound≫
[Structural unit (a0)]
In the polymer compound of the present invention (hereinafter referred to as polymer compound (A1)), the structural unit (a0) includes a structural unit represented by the general formula (a0-1).
The wavy line in formula (a0-1) is represented by the structure represented by the following general formula (a0-1-1) and the following general formula (a0-1-2). 2 types of geometric isomeric structures are included. The wavy lines in the following chemical formulas have the same meaning.
That is, in the structural unit (a0), there are two kinds of geometric isomer structures (syn isomer and anti isomer) due to a double bond between nitrogen and carbon.
In the polymer compound (A1), the structural unit (a0) may be a structural unit represented by the general formula (a0-1-1) or represented by the general formula (a0-1-1). It may be a structural unit or a mixture thereof.

［式中、Ｒ^１，Ｒ^２，Ｒ^３，Ｒ^４は上記と同様である。］

[Wherein R ¹ , R ² , R ³ and R ⁴ are the same as described above. ]

In formula (a0-1), R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group.
The lower alkyl group for R ¹ is linear or branched such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. Of lower alkyl groups.
Examples of the halogenated lower alkyl group for R ¹ include groups in which some or all of the hydrogen atoms of the lower alkyl group have been substituted with halogen atoms, and fluorinated lower alkyl groups are preferred.
R ¹ is preferably a hydrogen atom, a lower alkyl group or a fluorinated lower alkyl group, and most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.

R ² is an alkylene group or a fluorinated alkylene group.
The alkylene group for R ² may be linear, branched or cyclic, preferably linear or branched, and more preferably linear. 1-10 are preferable, as for carbon number of this alkylene group, 1-5 are more preferable, and 1-3 are more preferable. Specific examples include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, and an n-butylene group. Among these, n-propylene 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.

R ³ is an aryl group which may have a substituent.
In the aryl group of R ^3, the aryl group preferably has 6 to 18 carbon atoms in the basic ring excluding the substituent, more preferably 6 to 14 carbon atoms, and most preferably 6 to 10 carbon atoms. preferable.
More specifically, as the aryl group of R ^3, an optionally substituted phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, and the like Is mentioned. In the present invention, the aryl group for R ² is particularly preferably a 1-naphthyl group or a 2-naphthyl group.
Examples of the substituent that the aryl group of R ³ may have 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 halogenated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and still more preferably 1 to 3 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.
When the aryl group has a substituent, the number of the substituent is preferably in the range of 1 to 11, more preferably 1 to 7.

The halogenated alkyl group for R ⁴ may be linear, branched or cyclic, preferably linear or branched, more preferably linear. 1-10 are preferable, as for carbon number of this halogenated alkyl group, 1-5 are more preferable, 1-3 are more preferable, and 4 is the most preferable.
The halogenated alkyl group may be a group (partially halogenated alkyl group) in which a part of hydrogen atoms of the alkyl group is substituted with a halogen atom, and a group in which all of the hydrogen atoms are substituted with a halogen atom. (Fully halogenated alkyl group) may be used, and a fully halogenated alkyl group is preferred.
As the halogenated alkyl group, a fluorinated alkyl group is particularly preferable, and a fully fluorinated alkyl group in which all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable.

  In the present invention, the structural unit (a0) is preferably a structural unit represented by the following general formula (a0-11), and particularly preferably a structural unit represented by the following general formula (a0-12).

［式（ａ０−１１）中、Ｒ^２１は水素原子またはメチル基であり；Ｒ^２２は直鎖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^２３は置換基を有していてもよいフェニル基またはナフチル基であり；Ｒ^２４は炭素数１〜８のフッ素化アルキル基である。式（ａ０−１２）中、Ｒ^２１は水素原子またはメチル基であり、ｆは１〜５の整数である。］

[In formula (a0-11), R ²¹ represents a hydrogen atom or a methyl group; R ²² represents a linear or branched alkylene group having 1 to 5 carbon atoms or a fluorinated alkylene group; and R ²³ represents a substituted group. A phenyl group or a naphthyl group which may have a group; R ²⁴ is a fluorinated alkyl group having 1 to 8 carbon atoms. In formula (a0-12), R ²¹ represents a hydrogen atom or a methyl group, and f represents an integer of 1 to 5. ]

In formula (a0-11), examples of the alkylene group and fluorinated alkylene group for R ²² include the same alkylene groups and fluorinated alkylene groups as those described above for R ² .
In R ²³ , examples of the substituent that the phenyl group or naphthyl group may have include the same groups as those described above as the substituent that the aryl group of R ³ may have.
The fluorinated alkyl group for R ²⁴ may be linear, branched or cyclic, preferably linear or branched, and more preferably linear. 1-8 are preferable, as for carbon number of this fluorinated alkyl group, 1-4 are more preferable, and it is most preferable that it is 4.
The fluorinated alkyl group may be a group (partially fluorinated alkyl group) in which part of the hydrogen atoms of the alkyl group is substituted with fluorine atoms, and the group in which all of the hydrogen atoms are substituted with halogen atoms. (Fully fluorinated alkyl group) may be used, and a fully fluorinated alkyl group is preferred.

In formula (a0-12), the naphthyl group may be a 1-naphthyl group or a 2-naphthyl group.
f is preferably an integer of 1 to 8, more preferably 1 to 4, and most preferably 4.

In the polymer compound (A1), as the structural unit (a0), 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 (a0) in the polymer compound (A1) is preferably from 5 to 90 mol%, more preferably from 10 to 70 mol%, based on the total of all the structural units constituting the polymer compound (A1). 15-60 mol% is further more preferable, and 20-50 mol% is the most preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a0) can be sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

[Other structural units]
The polymer compound (A1) may have a structural unit other than the structural unit (a0). Such other structural units may be appropriately selected as necessary from those proposed so far as the structural units constituting the base resin for the chemically amplified resist composition.
Examples of the structural unit include a structural unit constituting the component (A2) described later. Specific examples include structural units (a ″ 1) to (a ″ 4) in the resin (A ″ 1), which will be described later. Examples thereof include structural units (a ″ 5) to (a ″ 7) in the resin (A ″ 2).

In the present invention, in particular, the polymer compound (A1) preferably further includes a structural unit (a1) having a hydrophilic group in addition to the structural unit (a0). Thereby, the hydrophilicity of the polymer compound (A1) is increased, and when forming a resist pattern, the affinity with a developer (alkaline aqueous solution) is increased and the resolution is improved.
Examples of the hydrophilic group include a hydroxyl group, a carboxy group, a hydroxyfluoroalkyl group (a hydroxyalkyl group in which some or all of the hydrogen atoms bonded to the carbon atom are substituted with a fluorine atom), an amino group, and —SO ₃ H. In particular, a hydroxyl group is preferred.
Specific examples of the structural unit (a1) include a structural unit (a ″ 3-1) derived from an acrylate ester containing a hydrophilic group-containing aliphatic hydrocarbon group, which is mentioned in the resin (A ″ 1) described later. Examples thereof include the structural unit (a ″ 6) mentioned in the resin (A ″ 2) described later.
These structural units may be appropriately selected in consideration of the type of exposure light source and the like. For example, when using a KrF excimer laser, an electron beam, etc., it is preferable to include the structural unit (a ″ 6). When using an ArF excimer laser, the structural unit (a ″ 3-1), particularly described later. It is preferable that the structural unit represented by Formula (a3-1) is included.

In the polymer compound (A1), as the structural unit (a1), one type of structural unit may be used, or two or more types may be used in combination.
The proportion of the structural unit (a1) in the polymer compound (A1) is preferably 10 to 90 mol%, more preferably 50 to 80 mol%, based on the total of all the structural units constituting the polymer compound (A1). 60 to 80 mol% is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a1) can be sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

In the present invention, the polymer compound (A1) has a lactone-containing cyclic group in addition to the structural unit (a0) or in addition to the structural units (a0) and (a1). The unit (a2) is preferably included.
Here, the lactone-containing cyclic group refers to a cyclic group containing one ring (lactone ring) containing an —O—C (O) — structure. 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 polymer compound (A1) is used for forming a resist film, the lactone-containing cyclic group of the structural unit (a2) can be used to increase the adhesion of the resist film to the substrate or with a developer containing water. It is effective in increasing affinity.
Specific examples of the structural unit (a2) include a structural unit (a ″ 2) in a resin (A ″ 1) described later.

In the polymer compound (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 polymer compound (A1) is preferably from 5 to 80 mol%, more preferably from 10 to 70 mol%, based on the total of all the structural units constituting the polymer compound (A1). 20 to 60 mol% is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a1) can be sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

  These structural units may be appropriately selected in consideration of the type of exposure light source and the like. For example, when a KrF excimer laser, an electron beam, or the like is used, the structural unit (a ″ 6) is preferably included. When an ArF excimer laser is used, the structural unit (a ″ 2) and / or (a ″ 3) is included. It is preferable to contain.

In the present invention, the polymer compound (A1) is a copolymer having at least two types of structural units (a0) and (a1), or at least two types of structural units (a0) and (a2). A copolymer having a unit is preferable, and a binary copolymer composed of the structural units (a0) and (a1) or a binary copolymer composed of the structural units (a0) and (a2) is particularly preferable. .
In the present invention, as the polymer compound (A1), in particular, a copolymer containing two kinds of structural units in the combination represented by the following general formula (A1-01), or a combination represented by the following general formula (A1-02) The copolymer containing these 2 types of structural units is preferable.

［式中、Ｒ^１０１〜Ｒ^１０４はそれぞれ独立に水素原子またはメチル基であり、ｆは前記と同じである。］

[Wherein, R ^{101 to} R ¹⁰⁴ each independently represents a hydrogen atom or a methyl group, and f is the same as defined above. ]

Although the mass mean molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of a high molecular compound (A1) is not specifically limited, 2000-100000 are preferable, 3000-80000 are more preferable, 5000-50000 Is most preferred. 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 4.0, and most preferably 1.2 to 3.5. In addition, Mn shows a number average molecular weight.

[Production of polymer compound (A1)]
In the polymer compound (A1), a monomer for deriving each structural unit was used, for example, a radical polymerization initiator such as dimethyl-2,2-azobis (2-methylpropionate) or azobisisobutyronitrile. It can be obtained by polymerization by known radical polymerization or the like.
Further, in the polymer compound (A1), a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH is used in combination in the above polymerization. it may be introduced -C _{(CF 3)} 2 -OH group at the terminal. 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

Here, the polymer compound (A1) of the present invention is a novel compound, and the monomer for deriving the structural unit (a0) is also a novel compound.
The monomer for deriving the structural unit (a0) is a compound represented by the following general formula (I) (hereinafter referred to as compound (I)).

［式中、Ｒ^１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^２はアルキレン基またはフッ素化アルキレン基であり；Ｒ^３は置換基を有していてもよいアリール基であり；Ｒ^４はハロゲン化アルキル基である。］

[Wherein, R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ² represents an alkylene group or a fluorinated alkylene group; and R ³ represents an aryl group which may have a substituent. Yes; R ⁴ is a halogenated alkyl group. ]

^R 1 in formula ^{(I), R 2, R} 3, R 4 are the same as ^{R 1, R 2, R 3} , R 4 respectively general formula (a0-1).

  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 the first step), a step of obtaining the compound (IV) represented by the following general formula (IV) from the compound (III) (hereinafter referred to as the second step), the compound (IV) ) From which the compound (V) represented by the following general formula (V) is obtained (hereinafter referred to as the third step), and the compound (V) and the compound (VI) represented by the following general formula (VI): And the step of obtaining compound (I) (hereinafter referred to as the fourth 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 chlorine atom is preferable.

"First step"
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.

"Second step"
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.

"Third step"
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.

"4th 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.
As the compound (VI), a commercially available product may be used or synthesized.
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.

In this invention, you may perform the process (isomer control process) of isolate | separating each isomer as needed before or after the 4th process. Thereby, compound (V) or compound (I) can be obtained as either single isomer.
That is, the compound (V) obtained in the third step is usually a mixture of a geometric isomer represented by the following general formula (Va) and a geometric isomer represented by the following general formula (Vb). . One of these geometric isomers is a syn isomer and the other is an anti 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 fourth step is performed using the geometric isomer represented by the general formula (Va), a geometric isomer represented by the following general formula (Ia) is obtained, which is represented by the general formula (Vb). When the fourth step is performed using the geometric isomer, a geometric isomer represented by the following general formula (Ib) is obtained.
On the other hand, when the fourth step is performed without isomer control, a mixture thereof is obtained. When the fourth step is carried out using such an isomer mixture, the resulting compound (I) is obtained from a geometric isomer represented by the following general formula (Ia) and a geometric isomer represented by the following general formula (Ib): A mixture of Therefore, when an isomer control step is performed after the fourth step, one of those geometric isomers can be obtained.

［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. ]

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 polymer compound (A1) of the present invention is a novel compound not conventionally known.
The polymer compound (A1) can be suitably used for the resist composition of the present invention described below.
That is, the polymer compound (A1) includes a structural unit (a0) having a structure represented by —R ² —SO ₂ —O—N═C (R ³ ) (R ⁴ ) at the side chain end. When the structure is irradiated with radiation, the bond in the structure is cleaved and decomposed into —R ² —SO ₃ H and C (R ³ ) (R ⁴ ) = NOH. That is, in the polymer compound (A1), an acidic group (—SO ₃ H) is formed by irradiation with radiation.
Formation of the acidic group increases the alkali solubility of the polymer compound (A1). Therefore, in the formation of the resist pattern, when selective exposure is performed on the resist film obtained using the resist composition containing the polymer compound (A1), the exposed portion turns into alkali-soluble while being unexposed. Since the portion remains insoluble in alkali and does not change, a resist pattern can be formed by performing alkali development.

Also, conventional chemically amplified resist compositions generally contain a resin component (base resin) whose alkali solubility is changed by the action of an acid and an acid generator that generates an acid upon irradiation with radiation. The alkali solubility of the resin component is increased by the action of the acid generated from the acid generator, and a resist pattern can be formed. As the acid generator, a low molecular weight non-polymer (hereinafter sometimes referred to as a low molecular weight acid generator) is usually used.
The acidic group in the polymer compound (A1) exhibits the same function as the acid generated from the acid generator. Therefore, the polymer compound (A1) can also be used as an acid generator, and the polymer compound (A1) can be used in place of the acid generator in a general chemical amplification resist composition. Therefore, by using the polymer compound (A1), the content of the low molecular weight acid generator is smaller than that of the conventional chemically amplified resist composition, or the resist composition does not contain any low molecular weight acid generator. Can be obtained.

≪Resist composition≫
The resist composition of the present invention contains the polymer compound (A1).
A high molecular compound (A1) may be used individually by 1 type, and may be used in combination of 2 or more type.
The content of the polymer compound (A1) 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 polymer compound in the organic solvent solution of the resist composition (the total concentration of the polymer compound (A1) and the later-described (A2) component optionally added), the higher the concentration. The resist film is thick.

<Optional component>
In addition to the polymer compound (A1), the resist composition of the present invention may further contain a resin component whose alkali solubility is changed by the action of an acid (hereinafter referred to as (A2) component).
When selective exposure is performed on a resist film obtained using the resist composition containing the component (A2), an acidic group is formed in the polymer compound (A1), and the action of the acidic group causes (A2 ) The alkali solubility of the component changes. For example, in the case of a resin component for a positive resist composition, alkali solubility increases, and in the case of a resin component for a negative resist composition, alkali solubility decreases.
As a result, while the alkali solubility of the exposed portion changes, the alkali solubility of the unexposed portion does not change. Therefore, a resist pattern can be formed by performing alkali development.
The component (A2) is not particularly limited, and many resin components have been proposed so far for resin components for chemically amplified resist compositions, such as resist compositions for ArF excimer lasers and resist compositions for KrF excimer lasers. Any of these may be selected and used.

When the resist composition of the present invention is a positive resist composition, as the component (A2), for example, part or all of the alkali-soluble groups in a resin having an alkali-soluble group (hydroxyl group, carboxy group, etc.) is acid dissociated. Resin protected with a soluble 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 (A2), an acrylic resin having an acid dissociable dissolution inhibiting group (hereinafter referred to as resin (A ″ 1)) or a PHS resin having an acid dissociable dissolution inhibiting group (hereinafter referred to as resin ( A ″ 2)) is preferred.

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 "1)]
Examples of the resin (A ″ 1) include a resin having a structural unit (a ″ 1) derived from an acrylate ester having an acid dissociable, dissolution inhibiting group.
The acid dissociable, dissolution inhibiting group in the structural unit (a ″ 1) has an alkali dissolution inhibiting property that makes the entire resin (A ″ 1) insoluble in alkali before dissociation, and the entire resin (A ″ 1) after dissociation. Can be used as long as the acid-dissolvable dissolution inhibiting group of the base resin for chemically amplified resists is used. A group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in 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 an acid (for example, an acidic group formed by exposure in the polymer compound (A1)) 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, “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.
“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 (a ″ 1) 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 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 unit represented by the following general formula (a ″ 1-1), an aliphatic cyclic group such as an adamantyl group such as a group bonded to an oxygen atom of a carbonyloxy group (—C (O) —O—) And a group having a group and a branched alkylene group having a tertiary carbon atom bonded thereto.

［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^１５、Ｒ^１６はアルキル基（直鎖、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 is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹⁵ and R ¹⁶ are alkyl groups (both linear and branched, preferably 1 to 5 carbon atoms). ). ]

  In the formula (a ″ 1-1), the lower alkyl group or halogenated lower alkyl group represented by R is the same as the lower alkyl group or halogenated lower alkyl group mentioned as the substituent at the α-position in the description of the acrylic ester. The same can be mentioned.

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 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 (a ″ 1), a group consisting of a structural unit represented by the following general formula (a ″ 1-0-1) and a structural unit represented by the following general formula (a ″ 1-0-2) It is preferable to use one or more selected from

［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 the general formula (a ″ 1-0-1), the lower alkyl group or halogenated lower alkyl group of 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. It is.
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 the general formula (a ″ 1-0-2), R is the same as described above.
X ² is the same as X ¹ in formula (a ″ 1-0-1).
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 (a ″ 1) 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 (a ″ 1), one type may be used alone, or two or more types may be used in combination.
Among the above, the structural unit represented by the general formula (a1-1) is preferable, and specifically, (a1-1-1) to (a1-1-6) or (a1-1-35) to (a1). It is more preferable to use at least one selected from structural units represented by -1-41).
Furthermore, the structural unit (a ″ 1) is represented by the following general formula (a ″ 1-1-01) including the structural units of the formula (a1-1-1) to the formula (a1-1-4). And the following general formula (a ″ 1-1-02) including the structural units of the formulas (a1-1-35) to (a1-1-41) are 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 (a ″ 1-1-01), R is the same as described 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 (a ″ 1-1-02), R is the same as described above. The lower alkyl group for R ^{12 is} the same as the lower alkyl group for R, and is preferably a methyl group or an ethyl group, and an ethyl group is Most preferably, h is preferably 1 or 2, and most preferably 2.

  In the resin (A ″ 1) component, the proportion of the structural unit (a ″ 1) is preferably 10 to 80 mol% and more preferably 20 to 70 mol% with respect to all the structural units constituting the resin (A ″ 1). When the resist composition is used, it is possible to easily obtain a pattern, and when the resist composition is used, the balance with other structural units is achieved. Can take.

-Structural unit (a "2):
The resin (A ″ 1) preferably further has a structural unit (a ″ 2) derived from an acrylate ester containing a lactone-containing cyclic group, in addition to the structural unit (a ″ 1).
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 (A ″ 1) is used for forming a resist film, the lactone cyclic group of the structural unit (a ″ 2) increases the adhesion of the resist film to the substrate, or contains a developer containing water. It is effective in increasing the affinity of.

The structural unit (a ″ 2) is not particularly limited, and any unit can be used.
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 (a ″ 2) 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 (A ″ 1), as the structural unit (a ″ 2), one type may be used alone, or two or more types may be used in combination.
The proportion of the structural unit (a ″ 2) in the resin (A ″ 1) is preferably 5 to 60 mol%, and preferably 10 to 60 mol%, based on the total of all structural units constituting the resin (A ″ 1). More preferably, it is more preferably 20 to 55 mol%. By making it the lower limit value or more, the effect of containing the structural unit (a ″ 2) can be sufficiently obtained, and by making it the upper limit value or less, other structural units Can be balanced.

-Structural unit (a "3):
In addition to the structural unit (a ″ 1) or in addition to the structural unit (a ″ 1) and the structural unit (a ″ 2), the resin (A ″ 1) may further contain a polar group-containing aliphatic hydrocarbon group. It is preferable to have a structural unit (a ″ 3) derived from an acrylate ester containing. By having the structural unit (a ″ 3), the hydrophilicity of the resin (A ″ 1) is increased, Affinity is increased, 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.

  As the structural unit (a ″ 3), 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, hydroxyethyl ester of acrylic acid is used. A derived structural unit is preferred, and 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- The structural unit represented by 3) is preferable.

（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 (a ″ 3), one type may be used alone, or two or more types may be used in combination.
As the structural unit (a ″ 3), a structural unit having a hydrophilic group such as a hydroxyl group, a carboxy group, or a hydroxyfluoroalkyl group as the polar group is particularly preferable. That is, the structural unit (a ″ 3) is hydrophilic. The structural unit (a ″ 3-1) derived from an acrylate ester containing a group-containing aliphatic hydrocarbon group is preferred. Specific examples of the structural unit (a ″ 3-1) include, for example, the above formula ( a structural unit represented by a3-1), a structural unit represented by formula (a3-3), and the like, and the structural unit represented by formula (a3-1) is particularly preferable.
In the resin (A ″ 1), the proportion of the structural unit (a ″ 3) is preferably 5 to 50 mol% with respect to all the structural units constituting the resin (A ″ 1), and 5 to 40 mol. % Is more preferable, and 5 to 25 mol% is more preferable.

-Structural unit (a "4):
The resin (A ″ 1) may contain other structural units (a ″ 4) other than the structural units (a ″ 1) to (a ″ 3) as long as the effects of the present invention are not impaired.
The structural unit (a ″ 4) is not particularly limited as long as it is another structural unit that is not classified into the above structural units (a ″ 1) to (a ″ 3). For ArF excimer laser and KrF excimer laser A number of hitherto known materials can be used for resist resins such as (preferably for ArF excimer laser).
The structural unit (a ″ 4) is preferably, for example, a structural unit derived from an acrylate ester containing a non-acid-dissociable aliphatic polycyclic group. The polycyclic group includes, for example, the structural unit described above. Examples similar to those exemplified in the case of (a ″ 1) can be exemplified and used for resin components of resist compositions such as for ArF excimer laser and for KrF excimer laser (preferably for ArF excimer laser). Many things conventionally known as a thing can be used.
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 (a ″ 4) include structures having 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 (a ″ 4) is contained in the resin (A ″ 1), the structural unit (a ″ 4) is added to the total of all the structural units constituting the resin (A ″ 1). 30 mol%, preferably 10 to 20 mol%, is preferable.

  In the present invention, the resin (A ″ 1) is preferably a copolymer having the structural units (a ″ 1), (a ″ 2) and (a ″ 3). Examples of such a copolymer include a copolymer comprising the structural units (a ″ 1), (a ″ 2) and (a ″ 3), the structural units (a ″ 1), (a ″ 2), Examples thereof include a copolymer comprising (a ″ 3) and (a ″ 4).

The resin (A ″ 1) can be obtained by polymerizing a monomer that derives each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). it can.
In addition, the resin (A ″ 1) is used in combination with a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH in the polymerization. In this way, a copolymer having a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom may be introduced as a -C (CF ₃ ) ₂ —OH group at the end. It is effective in reducing development defects and LER (line edge roughness: uneven unevenness of line side walls).

The mass average molecular weight (Mw) of the resin (A ″ 1) (polystyrene conversion standard by gel permeation chromatography) is not particularly limited, but is preferably 2000 to 50000, more preferably 3000 to 30000, and 5000 to 20000. If 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 if it is larger than the lower limit of this range, the dry etching resistance and resist pattern cross-sectional shape are good. is there.
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 "2)]
Examples of the resin (A ″ 2) include a resin having a structural unit (a ″ 5) 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. It is done.
The acid dissociable, dissolution inhibiting group-containing group in the structural unit (a ″ 5) may be the acid dissociable, dissolution inhibiting group itself, and the structure of the acid dissociable, dissolution inhibiting group and other groups and / or atoms It may be a group contained therein.

As the acid dissociable, dissolution inhibiting group for the structural unit (a ″ 5), the same groups as those described above for the structural unit (a ″ 1) can be used. In addition, in the structural unit (a ″ 5), a chain-like tertiary alkoxycarbonyl group, a chain-like 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 (a ″ 5) include structural units represented by the following general formula (a ″ 5-1).

［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 (a ″ 5-1), 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 (a ″ 5) can be used alone or in combination of two or more.
In the resin (A ″ 2), the proportion of the structural unit (a ″ 5) is preferably 10 to 90 mol%, and 50 to 80 mol% with respect to all the structural units constituting the resin (A ″ 2). When the resist composition is used, the pattern can be easily obtained, and when the resist composition is less than the upper limit, the amount of the other constituent units is less than the upper limit. Balance can be taken.

-Structural unit (a "6):
The resin (A ″ 2) preferably further has a structural unit (a ″ 6) derived from hydroxystyrene in addition to the structural unit (a ″ 5). As a result, the hydrophilicity of the resin (A ″ 2) is increased, the affinity with the developer is increased, the alkali solubility in the exposed area is improved, and the resolution is improved.
As the structural unit (a ″ 6), for example, a structural unit represented by the following general formula (a ″ 6-1) can be exemplified.

［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 (a ″ 6-1), R, R ⁶ , n13 and n14 are the same as R, R ⁵ , n11 and n12 in formula (a ″ 5-1), respectively.

The structural unit (a ″ 6) can be used alone or in combination of two or more.
The proportion of the structural unit (a ″ 6) in the resin (A ″ 2) is preferably 10 to 95 mol% with respect to all the structural units constituting the resin (A ″ 2), and is preferably 20 to 85 mol%. Is more preferably 30 to 80 mol%, particularly preferably 60 to 70 mol%, and within this range, moderate alkali solubility can be obtained and the balance with other structural units is good. .

-Structural unit (a "7):
The resin (A ″ 2) may further have a structural unit (a ″ 7) derived from styrene. By incorporating the structural unit (a ″ 7) into the resin (A ″ 2) and adjusting the content thereof, it is possible to adjust the solubility of the resin (A ″ 2) in an alkaline developer. Alkali solubility can be controlled and 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 (a ″ 7) include structural units represented by the following general formula (a ″ 7-1).

［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 (a ″ 7-1), examples of R and R ⁷ include the same as R and R ^{5 in} formula (a ″ 5-1).
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 (a ″ 7), one type may be used alone, or two or more types may be used in combination.
In the resin (A ″ 2), the proportion of the structural unit (a ″ 7) is preferably 1 to 20 mol% and more preferably 3 to 15 mol% with respect to all the structural units constituting the resin (A ″ 2). 5 to 15 mol% is particularly preferable.In this range, the effect of having the structural unit (a ″ 7) is high, and the balance with other structural units is also good.

・ Other structural units:
The resin (A ″ 2) may contain other structural units other than the structural units (a ″ 5) to (a ″ 7) as long as the effects of the present invention are not impaired. There is no particular limitation as long as it is another structural unit that is not classified into the structural units (a ″ 5) to (a ″ 7). For ArF excimer laser, for KrF positive excimer laser (preferably ArF excimer laser) For example, a number of conventionally known units can be used for resist resins such as the structural units (a ″ 1) to (a ″ 4) listed for the resin (A ″ 1). Etc.

  The resin (A ″ 2) is obtained by polymerizing a monomer for deriving each structural unit by a conventional method, for example, a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). be able to.

The resin (A ″ 2) preferably has a mass average molecular weight (Mw; polystyrene conversion by gel permeation chromatography (GPC)) in the range of 2000 to 50000, more preferably 3000 to 30000, and more preferably 5000 to 20000. When the Mw is not more than the upper limit of the above range, sufficient solubility in the resist solvent can be ensured, and the surface roughness of the resist pattern can be reduced. It is easy to adjust the solubility in the film, and the dry etching resistance is improved and the film loss is improved.
The smaller the degree of dispersion (Mw / Mn (number average molecular weight)) of the resin (A ″ 2), the better the resolution (the closer to monodispersion), the better. The degree of dispersion is 1.0 to 5.0. Is preferable, 1.0 to 3.0 is more preferable, and 1.0 to 2.5 is most preferable.

When the resist composition of this invention is a negative resist composition, the resist composition of this invention needs to contain alkali-soluble resin as (A2) component, and also a crosslinking agent is mix | blended. When such a negative resist composition is selectively exposed at the time of resist pattern formation, the exposed portion is crosslinked between the alkali-soluble resin and the crosslinking agent by the action of the acidic group formed in the polymer compound (A1). While this occurs and changes to alkali-insoluble, the unexposed portion remains alkali-soluble and does not change, so that a resist pattern is formed by performing alkali development.
As the alkali-soluble resin, a resin having a unit derived from at least one selected from α- (hydroxyalkyl) acrylic acid or a lower alkyl ester of α- (hydroxyalkyl) acrylic acid is a good resist with little swelling. A pattern can be formed, which is preferable. Note that 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 carbon atom) in the α-position carbon atom. One or both of [alpha] -hydroxyalkylacrylic acids to which (5) hydroxyalkyl groups) are attached.
As the crosslinking agent, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

(A2) A component may be used individually by 1 type and may be used in combination of 2 or more type.
When the component (A2) is blended, the content of the component (A2) is preferably 300 to 10000% by mass, and preferably 600 to 3000% by mass with respect to the polymer compound (A1) in consideration of solubility in the developer. Is more preferable. When it is at least the lower limit of the above range, the lithography properties are improved, and when it is at most the upper limit, pattern formation is sufficiently performed.

The resist composition of the present invention may contain an acid generator component (B) (hereinafter referred to as component (B)) that generates an acid upon irradiation with radiation. By including the component (B), sensitivity and the like are improved.
The component (B) 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.

  Examples of the onium salt acid generator include acid generators represented by the following general formula (b-0).

［式中、Ｒ^５１は、直鎖、分岐鎖若しくは環状のアルキル基、または直鎖、分岐鎖若しくは環状のフッ素化アルキル基を表し；Ｒ^５２は、水素原子、水酸基、ハロゲン原子、直鎖若しくは分岐鎖状のアルキル基、直鎖若しくは分岐鎖状のハロゲン化アルキル基、または直鎖若しくは分岐鎖状のアルコキシ基であり；Ｒ^５３は置換基を有していてもよいアリール基であり；ｕ”は１〜３の整数である。］

[Wherein R ⁵¹ represents a linear, branched or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group; R ⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, linear or A branched alkyl group, a linear or branched halogenated alkyl group, or a linear or branched alkoxy group; R ⁵³ is an optionally substituted aryl group; u "Is an integer from 1 to 3.]

In General Formula (b-0), R ⁵¹ represents a linear, branched, or cyclic alkyl group, or a linear, branched, or cyclic 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 preferably has 4 to 12 carbon atoms, more preferably 5 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms.
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 the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms in the fluorinated alkyl group (%)) is preferably 10 to 100%, more preferably 50 In particular, the one in which all the hydrogen atoms are substituted with fluorine atoms is preferable because the strength of the acid becomes strong.
R ⁵¹ is most preferably a linear alkyl group or a fluorinated alkyl group.

R ⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched alkyl group, a linear or branched alkyl halide group, or a linear or branched alkoxy group.
In R ⁵² , examples of the halogen atom include a fluorine atom, a bromine atom, a chlorine atom, and an iodine atom, and a fluorine atom is preferable.
In R ⁵² , the alkyl group is linear or branched, and the carbon number thereof is preferably 1 to 5, particularly 1 to 4, and more preferably 1 to 3.
In R ⁵² , the halogenated alkyl group is a group in which part or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms. Examples of the alkyl group herein are the same as the “alkyl group” in R ⁵² . Examples of the halogen atom to be substituted include the same as those described above for the “halogen atom”. In the halogenated alkyl group, it is desirable that 50 to 100% of the total number of hydrogen atoms are substituted with halogen atoms, and it is more preferable that all are substituted.
In R ⁵² , the alkoxy group is linear or branched, and the carbon number thereof is preferably 1 to 5, particularly 1 to 4, and more preferably 1 to 3.
Among these, R ⁵² is preferably a hydrogen atom.

R ⁵³ is an aryl group which may have a substituent, and examples of the structure of the basic ring (matrix ring) excluding the substituent include a naphthyl group, a phenyl group, an anthracenyl group, and the like. From the viewpoint of absorption of exposure light such as ArF excimer laser, a phenyl group is desirable.
Examples of the substituent include a hydroxyl group and a lower alkyl group (straight or branched chain, preferably having 5 or less carbon atoms, particularly preferably a methyl group).
As the aryl group for R ^53, an aryl group having no substituent is more preferable.
u ″ is an integer of 1 to 3, preferably 2 or 3, and particularly preferably 3.

  Preferable examples of the acid generator represented by the general formula (b-0) include the following.

  Moreover, as an onium salt type acid generator other than the acid generator represented by general formula (b-0), the compound represented by the following general formula (b-1) or (b-2) is mentioned, for example.

［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；Ｒ^４”は、直鎖、分岐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; R ⁴ ″ represents a linear, branched or cyclic alkyl group or fluorinated group. Represents an alkyl group; at least one of R ¹ ″ to 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. 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 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, ethyl group, propyl group, n-butyl group, or tert-butyl group. Is most preferred.
The alkoxy group that may be substituted with a hydrogen atom of the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and most preferably a methoxy group or an ethoxy 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, a straight, include alkyl groups such as branched or cyclic. 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.

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. It 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. Trifluoromethanesulfonate or nonafluorobutanesulfonate, triphenylsulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or nonafluorobutanesulfonate, tri (4-methylphenyl) sulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or the same Nonafluorobutanesulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of monophenyldimethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenylmonomethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate (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 heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate, di (1-naphthyl) phenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate. 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, Preferably it is C3.
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, preferably It is C1-C7, More preferably, it is C1-C3.
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.

  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, and still more preferably 90% or more.

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 anthracyl group, or a phenanthryl group. And heteroaryl groups in which some of the carbon atoms constituting the ring of these groups are substituted with heteroatoms such as oxygen, sulfur, and nitrogen atoms. 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, and most preferably a partially fluorinated alkyl group.
The fluorinated alkyl group in R ³⁵ preferably has 50% or more of the hydrogen atom of the alkyl group, more preferably 70% or more, and even more preferably 90% or more fluorinated. This is preferable because the strength of the acid is increased. 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]), WO2004 / 074242A2 (pages 65 to 85). The oxime sulfonate acid generators disclosed in Examples 1 to 40) of No. 1 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.

(B) As a component, these acid generators may be used individually by 1 type, and may be used in combination of 2 or more type.
When the component (B) is blended with the resist composition of the present invention, the content of the component (B) is preferably 1 to 30% by mass of the total amount of the polymer compound (A1) and the component (A2). 20 mass% is more preferable. When the amount is not less than the lower limit of the above range, the effect of blending the component (B) is sufficiently obtained, and when it is not more than the upper limit, a uniform solution is obtained when dissolved in an organic solvent, and storage stability is obtained. Is preferable because

In the resist composition of the present invention, a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) is further blended as an optional component in order to improve the resist pattern shape, the stability over time and the like. be able to.
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.
These may be used alone or in combination of two or more.
(D) When mix | blending a component, 0.01-5.0 mass% of the total amount of a high molecular compound (A1) and (A2) component is preferable.

The resist composition of the present invention comprises an organic carboxylic acid, a phosphorus oxo acid, and derivatives thereof as optional components for the purpose of preventing sensitivity deterioration and improving the resist pattern shape and stability with time. At least one compound (E) selected from the group (hereinafter referred to as component (E)) can be contained.
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) When mix | blending a component, the content has preferable 0.01-5.0 mass% of the total amount of a high molecular compound (A1) and (A2) component.

  The resist composition of the present invention further contains miscible additives as desired, for example, an additional resin for improving the performance of the resist film, a surfactant, a dissolution inhibitor, and a plasticizer for improving coatability. Stabilizers, colorants, antihalation agents, dyes, and the like can be added as appropriate.

<Organic solvent>
The resist composition of the present invention 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 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 pattern forming method of the present invention includes a step of forming a resist film on a support using the resist composition of the present invention, a step of exposing the resist film, and developing the resist film to form a resist pattern The process of carrying out is included.
The support is not particularly limited, and a conventionally known one can be used, and examples thereof include a substrate for electronic components and a substrate on which a predetermined wiring pattern is formed. 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 of the present invention 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 of the present invention is particularly effective for KrF excimer laser, ArF excimer laser, and EB.

The resist composition of the present invention is a novel one that has not been conventionally known.
Further, in the resist composition of the present invention, a resist pattern can be actually formed without containing a low molecular weight acid generator conventionally used in chemically amplified resist compositions. Therefore, the amount of the low molecular weight acid generator can be reduced or not added at all compared to the conventional resist composition. That is, the conventional chemically amplified resist composition is generally a two-component system containing at least a resin component (base resin) whose alkali solubility is changed by the action of an acid and a low molecular weight acid generator. It is. However, in the present invention, since the polymer compound (A1) has both a function as a base resin and a function as an acid generator, the resist composition of the present invention can be used as a resist even if it is a single component alone. A pattern can be formed.

In addition, the resist composition 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 300 nm or less, for example.
Furthermore, according to the resist composition of the present invention, roughness of the resist pattern surface can be reduced. Roughness causes distortion around the hole in the hole pattern and variation in line width in the line-and-space pattern, which may adversely affect the formation of fine semiconductor elements. For this reason, in recent years, the resist pattern has been increasingly miniaturized, and the demand for high resolution has further increased, so that improvement of LER has become a serious problem.
Moreover, according to the resist composition of this invention, generation | occurrence | production (outgas) of the gas at the time of resist pattern formation can be prevented. As a result, contamination of the exposure apparatus can be reduced, and therefore protection measures for these can be omitted, contributing to simplification of the process and the exposure apparatus.
The reason why the above-described effect can be obtained by the present invention is not clear, but the following reason is presumed. That is, in a conventional resist composition using a low molecular weight acid generator, each component appears to be uniformly mixed in a solvent. However, localization of the acid generator occurs everywhere in the resist film due to heating during film formation, and as a result, dissociation (deprotection) of the acid dissociable, dissolution inhibiting group in the resist film does not occur uniformly, It is presumed that roughness and deterioration of resolution will occur. Further, it is considered that the generated acid is gasified by heating PEB or the like and causes outgassing.
In contrast, in the present invention, the polymer compound (A1) has a group capable of generating an acidic group, and the acidic group is bonded to the polymer compound (A1). Therefore, it is presumed that the generation and diffusion of a low molecular weight acid in the resist film, the diffusion of the acid, the localization of the acid, and the like are prevented, and thereby the above effect is obtained.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
[Synthesis Example 1]
(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): δ (ppm) = − 128.0 to −125.5 (2F), −123.8 to −121.7 (2F), −126.7, −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 sequentially 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 obtain 6.88 g of a crude product of 2-naphthylnonafluorobutylketone. Obtained. The crude product was used in the next reaction without purification.

The instrumental analysis results of the obtained 2-naphthylnonafluorobutylketone (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): δ (ppm) = − 125.8 (2F), −122.5 (2F), −113.0 (2F), −81.6 (3F).

(Third step)
The crude product of 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-naphthylnonafluorobutylketone oxime.

The instrumental analysis results of the obtained 2-naphthylnonafluorobutylketone 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): 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-naphthylnonafluorobutylketone 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-naphthylnonafluorobutylketone oxime (corresponding to 79% of the theoretical value from 2-naphthaldehyde) was obtained.

The instrumental analysis results of the obtained 2-naphthylnonafluorobutylketone 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): δ (ppm) = − 126.0 (2F), −121.5 (2F), −110.7 (2F), −81.6 (3F).

It was confirmed by ¹⁹ F-NMR that 2-naphthylnonafluorobutylketone oxime was obtained as a pure stereoisomer (isomer control product). The ¹⁹ F-NMR chart is shown in FIG.
In addition, this isomer controlled product was subjected to X-ray crystal structure analysis. FIG. 3 shows a three-dimensional structure diagram of the isomer controlled product prepared based on the result.

(4th process)
2-Naphthyl nonafluorobutyl ketone oxime (isomer control product) 100.2 g and 4-dimethylaminopyridine 69.20 g were dissolved in DMF 250 ml and acetone 1 L. This solution was cooled to an internal temperature of 20 ° C. or lower, a solution of 3-chlorosulfonylpropyl methacrylate (SPM-Cl) 105.1 g in DMF 155 ml was added with stirring, and the mixture was stirred for 1 hour. Further, 250 ml of methanol was added at an internal temperature of 20 ° C. or lower and stirred for 1 hour. The reaction solution was poured into 10 L of water / 1 kg of normal salt with vigorous stirring and extracted with 5 L of ethyl acetate. The ethyl acetate solution was washed successively with 2 kg of 1N hydrochloric acid, 2 kg of 10% brine, 2 kg of 5% aqueous sodium hydrogen carbonate solution and 2 L of saturated brine twice. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure. The residue was recrystallized from 134 ml of diisopropyl ether (IPE) and 1340 ml of hexane to obtain 113.4 g of 2-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime (corresponding to 76% of the theoretical value). It was.

The instrumental analysis results of the obtained 2-naphthylnonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime are shown below.
Mp: 53.9 ° C.
IR (KBr) (ν / cm ⁻¹ ): 1714 (ν C═O), 1385 (ν SO ₂ ), 1280-1110 (ν CF.)
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 1.95 (3H, s, CH ₃ ), 2.20 to 2.30 (2H, m, CH ₂ ), 3.54 (2H, _{t, CH 2), 4.27 (} 2H, t, CH 2), 5.61 (1H, s, C = CH 2), 6.12 (1H, s, C = CH 2), 7.40 ( 1H, d, naphthyl), 7.56 to 7.65 (2H, m, naphthyl), 7.88 to 7.97 (4H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 125.9 (2F), −121.1 (2F), −110.5 (2F), −81.6 (3F).

It was confirmed by ¹⁹ F-NMR that 2-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime was obtained as a pure stereoisomer (isomer control product). The ¹⁹ F-NMR chart is shown in FIG.

[Synthesis Example 2]
After performing the first to third steps in the same procedure as in Synthesis Example 1, the fourth step was performed without performing the isomer control step. Thereby, 2-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime was obtained.
The instrumental analysis results of the obtained 2-naphthylnonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime are shown below.
Mp: 54.2 ° C.
IR (KBr) (ν / cm ⁻¹ ): 1715 (ν C═O), 1385 (ν SO ₂ ), 1280-1110 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 1.88, 1.95 (3H, s, CH ₃ ), 2.21 to 2.36 (2H, m, CH ₂ ), 3. _{54 (2H, m, CH 2} ), 4.28 (2H, m, CH 2), 5.51,5.61 (0.38H, 0.62H, s, C = CH 2), 6.06, _{6.12 (0.37H, 0.63H, s,} C = CH 2), 7.39~8.07 (7H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 126.7, −125.9 (0.76F, 1.24F), −121.1, −120.1 (1.24F, 0) .76F), -110.5, -107.3 (1.24F, 0.76F), -81.6, -81.3 (3F).

It was confirmed by ¹⁹ F-NMR that 2-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime was obtained as an isomer mixture. The ¹⁹ F-NMR chart is shown in FIG.

[Synthesis Example 3]
(First step)
C ₄ F ₉ SiMe ₃ 67.76g, was dissolved 1-naphthaldehyde 18.08g of 1,2-dimethoxyethane 36 ml. To this solution, 1.74 g of CsF was added in portions at room temperature with stirring. After further stirring for 2 hours, 36 ml of methanol was added and stirred overnight. The reaction solution was concentrated under reduced pressure, and 72 ml of toluene and 36 ml of saturated brine were added to the residue, followed by stirring for 30 minutes and liquid separation. The toluene solution was washed with 36 ml of saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. Recrystallization from hexane gave 28.89 g of α-nonafluorobutyl-1-naphthalenemethanol (corresponding to 66% of theory).

The instrumental analysis results of the obtained α-nonafluorobutyl-1-naphthalenemethanol are shown below.
Mp: 78.4 ° C.
IR (KBr) (ν / cm ⁻¹ ) 3481 (ν OH), 1290-1100 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 2.55 (1H, broadcast, OH), 6.14 (1H, d, CH), 7.49 to 7.60 (3H, m, naphthyl), 7.81-8.01 (4H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 128.2 to −125.4 (2F), −124.3 to −121.9 (2F), −127.8, −126. 8, -117.2, -116.2 (2F), -81.6 (3F).

(Second step)
α-Nonafluorobutyl-1-naphthalene methanol 28.88 g and diphosphorus pentoxide 27.24 g were suspended in DMF 77 ml. To this solution, 25.19 g of DMSO was added at room temperature with stirring. After further stirring for 2 hours, the mixture was cooled to 30 ° C. or lower. To the reaction solution were added 385 ml of toluene and 385 ml of water, and the mixture was stirred for 30 minutes and then separated. The toluene solution was washed successively with 97 ml of 5% aqueous sodium hydrogen carbonate solution and 97 ml of saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to obtain 31.55 g of a crude product of 1-naphthylnonafluorobutylketone. Obtained. The crude product was used in the next reaction without purification.

The instrumental analysis results of the obtained 1-naphthyl nonafluorobutyl ketone (crude product) are shown below.
IR (neat) (ν / cm ⁻¹ ): 1706 (ν C═O), 1280-1110 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 7.53 to 7.69 (3H, m, naphthyl), 7.92 (1H, d, naphthyl), 8.06 to 8.13 ( 2H, m, naphthyl), 8.42 (1H, d, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 125.9 (2F), −122.1 (2F), −112.8 (2F), −81.7 (3F).

(Third process)
The crude product 1-naphthyl nonafluorobutyl ketone 31.55 g and hydroxylamine hydrochloride 16.00 g were dissolved in methanol-modified ethanol 19 ml and pyridine 76 ml. This solution was heated and stirred at an internal temperature of 95 ° C. for 24 hours. The reaction solution was concentrated under reduced pressure, and 76 ml of water and 228 ml of ethyl acetate were added to the residue and stirred for 30 minutes. The reaction solution was separated, and the obtained ethyl acetate solution was washed successively with 76 ml of 1N hydrochloric acid twice and twice with 76 ml of saturated brine. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure to obtain 28.37 g of a crude product of 1-naphthylnonafluorobutylketone oxime. The crude product was used in the next reaction without purification.

The instrumental analysis results of the obtained 1-naphthylnonafluorobutylketone oxime (crude product) are shown below.
IR (neat) (ν / cm ⁻¹ ): 3318 (ν OH), 1270 to 1120 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 7.41 to 7.64 (5H, m, naphthyl), 7.81 to 7.98 (2H, m, naphthyl), 8.78, 9.11 (0.68H, 0.32H, broadcast, OH).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 127.1, −125.9 (0.62F, 1.38F), −121.2, −120.2 (1.33F, 0) .67F), -111.8 to -108.3, -109.0 (1.38F, 0.62F), -81.7, -81.5 (3F).

It was confirmed by ¹⁹ F-NMR that 1-naphthylnonafluorobutylketone oxime was obtained as an isomer mixture. The ¹⁹ F-NMR chart is shown in FIG.
In the chart, peaks derived from 1-naphthyl nonafluorobutyl ketone, which is an unreacted raw material, overlap at δ = −125.9 and −81.7.

(Fourth process)
The crude product 1-naphthylnonafluorobutylketone oxime 28.37 g and 4-dimethylaminopyridine 19.59 g were dissolved in DMF 73 ml and acetone 292 ml. This solution was cooled to an internal temperature of 20 ° C. or lower, and 29.74 g of 3-chlorosulfonylpropyl methacrylate (SPM-Cl) was added with stirring, followed by stirring for 1 hour. Further, 73 ml of methanol was added at an internal temperature of 20 ° C. or lower and stirred for 1 hour. The reaction mixture was poured into 2920 ml of water / 292 g of normal salt with vigorous stirring and extracted with 1460 ml of ethyl acetate. The ethyl acetate solution was sequentially washed twice with 584 ml of 1N hydrochloric acid, 584 ml of 10% brine, 584 ml of 5% aqueous sodium hydrogen carbonate solution and 584 ml of saturated brine. The ethyl acetate solution was dried over magnesium sulfate and concentrated under reduced pressure. When recrystallized from 38 ml of IPE and 380 ml of hexane, 19.95 g of 1-naphthylnonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime (to 45% of the theoretical value from α-nonafluorobutyl-1-naphthalenemethanol) Equivalent) was obtained.

The instrumental analysis results of the obtained 1-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime are shown below.
Mp: 78.6 ° C.
^{IR (KBr) (ν / cm} -1): 1705 (ν C = O), 1384 (ν SO 2), 1280~1120 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 1.86, 1.96 (0.26H, 2.74H, s, CH ₃ ), 2.15 to 2.36 (2H, m, _{CH 2), 3.51 (2H,} m, CH 2), 4.25 (2H, m, CH 2), 5.50,5.62 (0.08H, 0.92H, s, C = CH 2 _{), 6.02,6.13 (0.08H, 0.92H,} s, C = CH 2), 7.42~8.05 (7H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 126.8, −125.8 (0.20F, 1.80F), −120.8, −119.6 (1.80F, 0) .20F), -111.5 to -108.3, -107.7 (1.83F, 0.17F), -81.7, -81.4 (3F).

It was confirmed by ¹⁹ F-NMR that 1-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime was obtained as a mixture of two isomers (mixing ratio of about 9: 1). . The ¹⁹ F-NMR chart is shown in FIG.

(Isomer control process)
The obtained isomer mixture was recrystallized twice from IPE / hexane to give 16.14 g (α-nona) of an isomer control product of 1-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime. 36% of theory from fluorobutyl-1-naphthalenemethanol) was obtained.
The instrumental analysis results of the obtained isomer control product are shown below.
Mp: 82.0 ° C.
^{IR (KBr) (ν / cm} -1): 1706 (ν C = O), 1383 (ν SO 2), 1280~1120 (ν CF).
¹ H-NMR (CDCl ₃ , 300 MHz): δ (ppm) = 1.96 (3H, s, CH ₃ ), 2.15 to 2.24 (2H, m, CH ₂ ), 3.51 (2H, _{t, CH 2), 4.24 (} 2H, t, CH 2), 5.62 (1H, s, C = CH 2), 6.13 (1H, s, C = CH 2), 7.44 ( 1H, d, naphthyl), 7.54 to 7.63 (4H, m, naphthyl), 7.92 to 8.05 (2H, m, naphthyl).
¹⁹ F-NMR (CDCl ₃ , 283 MHz): δ (ppm) = − 125.8 (2F), −120.8 (2F), −111.5 to −108.3 (2F), −81.7 ( 3F).

It was confirmed by ¹⁹ F-NMR that 1-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime was obtained as an isomer controlled product. The ¹⁹ F-NMR chart is shown in FIG.

[Synthesis Example 4: Synthesis of polymer compound]
16.20 g (100 mmol) of p-acetoxystyrene as a monomer and 14.13 g (25 mmol) of 2-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime (isomer control product) obtained in Synthesis Example 1 As a polymerization initiator, 2.88 g (12.5 mmol) of dimethyl 2,2-azobis (2-methylpropionate) was dissolved by adding 45.49 g of ethyl lactate (EL) to prepare a monomer solution.
The monomer solution was added dropwise to 25.27 g of EL heated to 80 ° C., stirred for 6 hours, and allowed to stand for 1 hour. Thereafter, the reaction solution is dropped into a mixed solvent of methanol-water (methanol: water = 95: 5 (volume ratio)), reprecipitated and purified with methanol-water and n-heptane, and dried. Gave 22.18 g of a white solid.
The resulting white solid, the molecular weight and degree of dispersion is calculated from the GPC results were calculated composition of (proportion of the respective structural units in the polymer compound (mol%)) from ^{1 H-NMR. 1} H-NMR data is shown below.
¹ H-NMR (CDCl ₃ , 270 MHz): δ (ppm) = 2.20 (3H, s, acyl), 3.00 to 3.60 (6H, s, — (CH ₂ ) ₃ —), 6. 80 (4H, s, phenyl), 8.10, 7.65, 7.45 (7H, s, naphthyl).

  From the above results, the obtained white solid is a copolymer (1) represented by the following formula (1) (yield 73%, molecular weight (Mw) 6900, dispersity (Mw / Mn) 1.58). It was confirmed that there was. In the formula (1), x0 and y0 represent the proportion of each structural unit, and x0: y0 = 76.5: 23.5 (molar ratio).

2 g (7.94 mmol) of the copolymer (1) was dissolved in 4 g of tetrahydrofuran (THF), 0.387 g (6.18 mmol) of 80% hydrazine aqueous solution was added, and the mixture was stirred at room temperature for 1 hour. Then, it was dripped in a lot of water and the deposit was obtained. This precipitate was separated by filtration, washed, purified by reprecipitation and dried to obtain 1.49 g of a white solid.
About the obtained white solid, the molecular weight, the dispersity, and the composition were calculated in the same manner as described above, and the thermal decomposition temperature (Td) and the glass transition temperature (Tg) were measured. ¹ H-NMR data is shown below.
¹ H-NMR (DMSO, 270 MHz): δ (ppm) = 3.00 to 3.60 (6H, s, — (CH ₂ ) ₃ —), 6.50 (4H, s, phenyl), 8.10 , 7.65, 7.45 (7H, s, naphthyl), 8.98 (1H, s, OH).

  From the above results, the obtained white solid was a copolymer (A1-1) represented by the following formula (A1-1) (yield 86%, Mw5800, Mw / Mn1.89, Td250 ° C, Tg102 ° C). It was confirmed that. In formula (A1-1), x1 and y1 represent the proportion of each structural unit, and x1: y1 = 75.7: 24.3 (molar ratio).

[Synthesis Example 5: Synthesis of polymer compound]
1-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propane obtained in Synthesis Example 3 instead of 2-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyl oxime (isomer control product) 2.51 g of a white solid was obtained in the same manner as in Synthesis Example 4 except that sulfonyloxime (isomer control product) was used.
About the obtained white solid, molecular weight, dispersity, composition, Td and Tg were determined in the same manner as described above. ¹ H-NMR data is shown below.
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 3.00 to 3.80 (6H, s, — (CH ₂ ) ₃ —), 6.50 (4H, s, phenyl), 8.10 , 7.60, 7.45 (7H, s, naphthyl), 9.00 (1H, s, OH).

  From the above results, the obtained white solid was a copolymer (A1-2) represented by the following formula (A1-2) (yield 96%, molecular weight 5900, dispersity 1.75, Td248 ° C., Tg 100 ° C. ). In formula (A1-2), x2 and y2 represent the proportion of each structural unit, and x2: y2 = 75: 25 (molar ratio).

[Synthesis Example 6: Synthesis of polymer compound]
2-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime obtained in Synthesis Example 1, 7.23 g of 5-methacryloyloxy-2,6-norbornanecarbolactone, and azobisiso 0.41 g of butyronitrile was dissolved in 8.73 g of THF. The solution was refluxed for 3 hours, cooled to room temperature, slowly dropped into methanol / water = 9/1, and the resulting precipitate was filtered. After dissolving the filtrate in THF again, it was slowly added dropwise to methanol / water = 9/1, and the resulting precipitate was filtered to obtain a copolymer represented by the following formula (A1-3) ( A1-3) (molecular weight 47900, dispersity 3.52, Td276 ° C., Tg 217 ° C.). In formula (A1-3), x3 and y3 represent the proportion of each structural unit, and x3: y3 = 49: 51 (molar ratio).

[Example 1]
100 parts by mass of the copolymer (A1-1) obtained in Synthesis Example 4 and 1900 parts by mass of PGMEA were mixed and dissolved to prepare a positive resist composition.

[Example 2]
100 parts by mass of the copolymer (A1-2) obtained in Synthesis Example 5 and 1900 parts by mass of PGMEA were mixed and dissolved to prepare a positive resist composition.

[Example 3]
100 parts by mass of the copolymer represented by the following chemical formula (A2-1) and 15 parts by mass of the copolymer (A1-3) obtained in Synthesis Example 6 were mixed and dissolved in 1900 parts by mass of PGMEA to be positive. A mold resist composition was prepared. In formula (A2-1), the numerical value on the lower right of () indicates the ratio (molar ratio) of each structural unit.

（質量平均分子量１００００、分散度２．０）

(Mass average molecular weight 10,000, dispersity 2.0)

The following evaluation was performed using the resist composition of Example 1 or 2.
[EB lithography evaluation]
The resist composition shown in Table 1 was uniformly applied on an 8-inch silicon substrate that had been subjected to hexamethyldisilazane treatment, and was subjected to a baking treatment (PAB) for 90 seconds at the PAB temperature shown in Table 1 to form a film. A resist film having a thickness of 100 nm was obtained.
The resist film was drawn with an exposure amount shown in Table 1 using an electron beam drawing machine Hitachi HL-800D (manufactured by Hitachi, Ltd., acceleration voltage: 70 kV), and then at a PEB temperature shown in Table 1 for 90 seconds. Bake treatment (PEB) was performed, development was performed with a 2.38 mass% TMAH aqueous solution (23 ° C.) for 60 seconds, and then rinsed with pure water for 60 seconds, followed by shaking and drying.
Thereafter, whether or not a pattern was formed on the substrate was observed with a scanning electron microscope (SEM). As a result, in any of Examples 1 to 3, a line-and-space (1: 1) resist pattern (hereinafter referred to as a 1: 1 LS pattern) in which line patterns having a line width of 100 nm are arranged at equal intervals (pitch: 200 nm). Was formed).
Moreover, the limit resolution (nm) in the exposure amount shown in Table 1 was calculated. The results are also shown in Table 1.

[KrF lithography evaluation]
As a support, an 8-inch silicon substrate subjected to hexamethyldisilazane treatment (without BARC), and an organic antireflection film composition “ARC-29” (trade name, manufactured by Brewer Science) on the substrate, A substrate (with BARC) on which an organic antireflection film (BARC) having a film thickness of 77 nm was formed by coating using a spinner, baking on a hot plate at 205 ° C. for 60 seconds, and drying was prepared.
The resist composition obtained in Example 1 was uniformly coated on each of the above supports, and was baked (PAB) at 80 ° C. for 90 seconds to form a resist film having a thickness of 230 nm. .
A KrF excimer laser (248 nm) was applied to the resist film with an exposure amount shown in Table 2 using a KrF exposure apparatus S-203B (manufactured by Nikon; NA (numerical aperture) = 0.68, σ = 0.60). Then, after selectively irradiating through a mask pattern, baking processing (PEB) is performed at 80 ° C. for 90 seconds, development is performed with a 2.38 mass% TMAH aqueous solution (23 ° C.) for 60 seconds, and then pure water is used for 60 seconds. The sample was rinsed with water and shaken and dried.
Thereafter, whether or not a pattern was formed on the substrate was observed with a scanning electron microscope (SEM). As a result, a 1: 1 LS pattern with a line width of 300 nm was formed.
Further, the limit resolution (nm) at the exposure amount shown in Table 2 was obtained. The results are also shown in Table 2.

[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 77 nm was formed. On the antireflection film, the positive resist composition of Example 3 was applied using a spinner, prebaked (PAB) treatment at 110 ° 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 125 ° C. for 60 seconds, and further developed with an aqueous 2.38 mass% tetramethylammonium hydroxide (TMAH) solution at 23 ° C. for 30 seconds, then washed with water for 30 seconds, and then shaken and dried. As a result, resolution of a resist pattern having a line width of 200 nm and a pitch of 400 nm was confirmed. The sensitivity at that time was 89 mJ / cm ₂ .

Synthesis Example 1: ¹⁹ F-NMR chart of 2-naphthylnonafluorobutylketone oxime (isomer mixture). Synthesis Example 1: ¹⁹ F-NMR chart of 2-naphthylnonafluorobutylketone oxime (isomer control product). It is a three-dimensional structure drawing created based on the X-ray crystal structure analysis result of 2-naphthyl nonafluorobutyl ketone oxime (isomer control product). Synthesis Example 1: ¹⁹ F-NMR chart of 2-naphthylnonafluorobutylketone O-3- (methacryloyloxy) propanesulfonyloxime (isomer control product). Synthesis example 2: ¹⁹ F-NMR chart of 2-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime (isomer mixture). Synthesis Example 3: ¹⁹ F-NMR chart of 1-naphthylnonafluorobutylketone oxime (isomer mixture). Synthesis Example 3: ¹⁹ F-NMR chart of 1-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime (isomer mixture). Synthesis Example 3: ¹⁹ F-NMR chart of 1-naphthyl nonafluorobutyl ketone O-3- (methacryloyloxy) propanesulfonyloxime (isomer control product).

Claims (7)

The high molecular compound containing the structural unit (a0) represented by the following general formula (a0-1).

[Wherein, R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ² represents an alkylene group or a fluorinated alkylene group; and R ³ represents an aryl group which may have a substituent. Yes; R ⁴ is a halogenated alkyl group. ]   Furthermore, the high molecular compound of Claim 1 containing the structural unit (a1) which has a hydrophilic group.   Furthermore, the high molecular compound of Claim 1 or 2 containing the structural unit (a2) which has a lactone containing cyclic group. A resist composition comprising a polymer compound (A1) containing a structural unit (a0) represented by the following general formula (a0-1).

[Wherein, R ¹ represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ² represents an alkylene group or a fluorinated alkylene group; and R ³ represents an aryl group which may have a substituent. Yes; R ⁴ is a halogenated alkyl group. ]   The resist composition according to claim 4, wherein the polymer compound (A1) further comprises a structural unit (a1) having a hydrophilic group.   The resist composition according to claim 4 or 5, wherein the polymer compound (A1) further comprises a structural unit (a2) having a lactone-containing cyclic group.   A step of forming a resist film on a support using the resist composition according to any one of claims 4 to 6, a step of exposing the resist film, and developing the resist film to form a resist pattern A resist pattern forming method including the step of:

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