JP2006036891A - alpha-UNSATURATED ACYLOXY-gamma-BUTYLOLACTONE DERIVATIVE, POLYMER COMPOUND AND RESIN COMPOSITION FOR PHOTORESIST - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compound having a new lactone skeleton which is useful as a constituent monomer for photoresist resins. <P>SOLUTION: The α-unsaturated acyloxy-γ-butylolactone derivative is represented by formula (1) (wherein R<SP>a</SP>is a hydrogen atom, a halogen atom, a 1-6C alkyl group or a 1-6C haloalkyl group;R<SP>b</SP>is an acid-leaving group; R<SP>1</SP>and R<SP>2</SP>are same or different and they are each a hydrocarbon group and R<SP>1</SP>and R<SP>2</SP>may mutually be combined to form a ring together with an adjacent carbon atom; R<SP>3</SP>and R<SP>4</SP>are same or different and they are each hydrogen atom or a hydrocarbon group). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polymer compound for a photoresist used when performing microfabrication of a semiconductor, a novel α-unsaturated acyloxy-γ-butyllactone useful as a monomer of the polymer compound, and the polymer compound The present invention relates to a resin composition for photoresists containing selenium and a method for producing a semiconductor using the resin composition for photoresists.

  Resin for photoresist used in the semiconductor manufacturing process has the property that some groups are eliminated by acid generated from a photoacid generator by light irradiation and become soluble in an alkali developer (acid detachment, alkali Soluble), adhesion to a silicon wafer (substrate), plasma etching resistance, transparency to light used, etc. must be combined. The photoresist resin is generally used as a solution containing a main polymer, a photo-oxidant, and several additives for adjusting the above characteristics.

  Conventionally, in a photoresist resin, a monomer unit having a 2-methyladamantan-2-yl group or a 1-adamantyl-1-methylethyl group is used as a monomer unit that imparts acid detachability (alkali solubility). (For example, patent document 1 etc.). However, these monomer units are generally highly hydrophobic and have a large polarity difference from highly hydrophilic monomer units that impart substrate adhesion. Therefore, when a multi-element polymer is produced by copolymerizing the monomer that imparts acid detachability and a highly hydrophilic monomer that imparts substrate adhesion, a homopolymer or a polymer in which specific monomer units are unevenly distributed is likely to be generated. . When such a low uniformity polymer is used as a resin for a photoresist, there is a polymer that does not become alkali-soluble even after development because there are few acid-eliminable groups, so the line edge roughness is large, clear and High precision line and space cannot be obtained.

JP-A-9-73173

Accordingly, an object of the present invention is to provide a novel polymerizable compound useful as a constituent monomer of a photoresist resin. Another object is to provide a novel polymerizable compound that can impart acid detachability and has high polarity.
Still another object of the present invention is to provide a novel polymer compound that is useful as a photoresist resin and has a high uniformity of monomer composition.
Another object of the present invention is to provide a photoresist resin composition and a semiconductor manufacturing method capable of forming a fine pattern clearly and accurately.

  As a result of intensive studies to achieve the above object, the present inventors have found that when an α-unsaturated acyloxy-γ-butyrolactone derivative having an acid-eliminable group in the molecule is used as a constituent monomer of a photoresist resin, A highly uniform copolymer in which a detachable monomer unit, a substrate adhesion monomer unit, etc. are uniformly incorporated into the molecule is obtained, and a fine pattern is increased by using such a polymer for semiconductor production. The present invention was completed by finding that it can be formed with high accuracy.

（式中、Ｒ^aは水素原子、ハロゲン原子、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を示す。Ｒ^bは酸により脱離可能な基を示す。Ｒ¹、Ｒ²は、同一又は異なって、炭化水素基を示す。Ｒ¹及びＲ²は、互いに結合して、隣接する炭素原子と共に環を形成していてもよい。Ｒ³、Ｒ⁴は、同一又は異なって、水素原子又は炭化水素基を示す）
で表されるα−不飽和アシルオキシ−γ−ブチロラクトン誘導体を提供する。 That is, the present invention provides the following formula (1):

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms. R ^b represents a group removable by an acid. R ¹ , R ² is the same or different and represents a hydrocarbon group, R ¹ and R ² may be bonded to each other to form a ring together with adjacent carbon atoms, and R ³ and R ⁴ may be the same or different. Represents a hydrogen atom or a hydrocarbon group)
An α-unsaturated acyloxy-γ-butyrolactone derivative represented by the formula:

（式中、Ｒ^aは水素原子、ハロゲン原子、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を示す。Ｒ^bは酸により脱離可能な基を示す。Ｒ¹、Ｒ²は、同一又は異なって、炭化水素基を示す。Ｒ¹及びＲ²は、互いに結合して、隣接する炭素原子と共に環を形成していてもよい。Ｒ³、Ｒ⁴は、同一又は異なって、水素原子又は炭化水素基を示す）
で表される少なくとも１種のモノマー単位を含む高分子化合物を提供する。 The present invention also provides the following formula (I)

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms. R ^b represents a group removable by an acid. R ¹ , R ² is the same or different and represents a hydrocarbon group, R ¹ and R ² may be bonded to each other to form a ring together with adjacent carbon atoms, and R ³ and R ⁴ may be the same or different. Represents a hydrogen atom or a hydrocarbon group)
The high molecular compound containing the at least 1 sort (s) of monomer unit represented by these is provided.

  The polymer compound may further include a monomer unit [excluding the monomer unit represented by the formula (I)] having a group that is partly eliminated by an acid and becomes alkali-soluble. May contain a monomer unit [excluding the monomer unit represented by the formula (I)] capable of imparting adhesiveness to the resin.

（式中、Ｒ^aは水素原子、ハロゲン原子、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を示す。Ｒ⁵及びＲ⁶は、同一又は異なって、炭素数１〜８の炭化水素基を示し、Ｒ⁷、Ｒ⁸及びＲ⁹は、同一又は異なって、水素原子、ヒドロキシル基又はメチル基を示す。Ｒ¹⁰及びＲ¹¹は、同一又は異なって、水素原子、ヒドロキシル基又は−ＣＯＯＲ¹²基を示し、Ｒ¹²はｔ−ブチル基、２−テトラヒドロフラニル基、２−テトラヒドロピラニル基又は２−オキセパニル基を示す。Ｒ¹³はメチル基又はエチル基を示し、Ｒ¹⁴及びＲ¹⁵は、同一又は異なって、水素原子、ヒドロキシル基又はオキソ基を示す。Ｒ¹⁶は、式中に示される酸素原子との結合部位に第３級炭素原子を有する、置換基を有していてもよい炭化水素基を示す。Ｒ¹⁷、Ｒ¹⁸、Ｒ¹⁹、Ｒ²⁰及びＲ²¹は、同一又は異なって、水素原子又はメチル基を示す。Ｒ²²はｔ−ブチル基、２−テトラヒドロフラニル基、２−テトラヒドロピラニル基又は２−オキセパニル基を示す。Ｒ²³、Ｒ²⁴は、同一又は異なって、水素原子、アルキル基又はフルオロアルキル基を示し、Ｒ²⁵は水素原子又は有機基を示す。ｍは１〜３の整数を示し、ｎは０又は１を示す）
から選択された少なくとも１種のモノマー単位とを含んでいてもよい。 The polymer compound includes at least one monomer unit represented by the formula (I) and the following formulas (IIa) to (IIh):

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms or a haloalkyl group having 1 to 6 carbon atoms. R ⁵ and R ⁶ are the same or different and have 1 to 8 carbon atoms. R ⁷ , R ⁸ and R ⁹ are the same or different and represent a hydrogen atom, a hydroxyl group or a methyl group, and R ¹⁰ and R ¹¹ are the same or different and represent a hydrogen atom, a hydroxyl group Or -COOR ¹² group, R ¹² represents a t-butyl group, 2-tetrahydrofuranyl group, 2-tetrahydropyranyl group or 2-oxepanyl group, R ¹³ represents a methyl group or an ethyl group, R ¹⁴ and R ¹⁵ is the same or different and represents a hydrogen atom, a hydroxyl group or an oxo group, and R ¹⁶ has a substituent having a tertiary carbon atom at the bonding site with the oxygen atom shown in the formula. .R ¹⁷ showing a which may be a hydrocarbon group, ^18, R ^19, R ²⁰ and R ²¹ are the same or different, .R ²² represent a hydrogen atom or a methyl group is t- butyl, 2-tetrahydrofuranyl group, 2-tetrahydropyranyl group or a 2-oxepanyl group R ²³ and R ²⁴ are the same or different and each represents a hydrogen atom, an alkyl group or a fluoroalkyl group, R ²⁵ represents a hydrogen atom or an organic group, m represents an integer of 1 to 3, and n represents 0 or 1)
And at least one monomer unit selected from the group consisting of:

（式中、Ｒ^aは水素原子、ハロゲン原子、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を示す。Ｒ²⁶及びＲ²⁷は、同一又は異なって、水素原子、ヒドロキシル基又はカルボキシル基を示し、Ｒ²⁸はヒドロキシル基、オキソ基又はカルボキシル基を示す。Ｘ¹、Ｘ²及びＸ³は、同一又は異なって、−ＣＨ₂−又は−ＣＯ−Ｏ−を示す。Ｒ²⁹、Ｒ³⁰及びＲ³¹は、同一又は異なって、水素原子又はメチル基を示す。Ｒ³²及びＲ³³は、同一又は異なって、水素原子又はメチル基を示す。Ｒ³⁴、Ｒ³⁵、Ｒ³⁶、Ｒ³⁷及びＲ³⁸は、同一又は異なって、水素原子又はメチル基を示す。Ｒ³⁹は、水素原子、又は置換基を有していてもよい炭素数１〜２０の直鎖状、分岐鎖状、環状若しくは有橋環状炭化水素基を示す。Ｒ⁴⁰、Ｒ⁴¹、Ｒ⁴²及びＲ⁴³は、同一又は異なって、水素原子又はメチル基を示す。Ｒ⁴⁴は、水素原子、ヒドロキシル基、ヒドロキシメチル基又はカルボキシル基を示す。ｏ、ｐ、ｑ及びｒは、それぞれ、０又は１を示す）
で表されるモノマー単位から選択された少なくとも１種のモノマー単位を含んでいてもよい。 The polymer compound may have the following formulas (IIIa) to (IIIh):

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms or a haloalkyl group having 1 to 6 carbon atoms. R ²⁶ and R ²⁷ are the same or different and each represents a hydrogen atom or a hydroxyl group. or a carboxyl group, R ²⁸ represents a hydroxyl group, .X ^1, X ² and X ³ showing an oxo group or a carboxyl group are the same or different, -CH ₂ - or -CO-O- shown .R ²⁹ , R ³⁰ and R ³¹ are the same or different and each represents a hydrogen atom or a methyl group, and R ³² and R ³³ are the same or different and each represents a hydrogen atom or a methyl group, R ³⁴ , R ³⁵ , R ³⁶ , R ³⁷ and R ³⁸ are the same or different and each represents a hydrogen atom or a methyl group, and R ³⁹ is a hydrogen atom or a linear or branched chain having 1 to 20 carbon atoms which may have a substituent. , .R ^40, R ⁴¹ showing a cyclic or bridged cyclic hydrocarbon group, R ⁴² and ⁴³ are the same or different, .R ⁴⁴ represent a hydrogen atom or a methyl group, a hydrogen atom, a hydroxyl group, .o showing a hydroxymethyl group or a carboxyl group, p, q and r are, respectively, 0 or 1 Show)
It may contain at least one monomer unit selected from the monomer units represented by:

  The present invention further provides a photoresist resin composition comprising at least the polymer compound and a photoacid generator.

  The present invention further provides a method for producing a semiconductor, comprising a step of applying the photoresist resin composition on a substrate or a substrate to form a resist coating film, and forming a pattern through exposure and development. .

ADVANTAGE OF THE INVENTION According to this invention, the novel compound which can provide acid detachability and can improve the uniformity of the monomer composition in the copolymer calculated | required by resin for photoresists is provided.
Since the polymer compound of the present invention uses the highly hydrophilic acid detachable monomer as a monomer component, the polymer molecule has a small polarity difference from the highly hydrophilic substrate adhesion monomer and has few acid detachable monomer units. Is not generated, and the uniformity of the monomer composition of the multi-component polymer is improved. Therefore, according to the photoresist resin composition and semiconductor manufacturing method of the present invention using such a polymer compound, a line edge without unevenness can be obtained by development, and a fine pattern can be formed clearly and accurately. Can do.

[Α-Unsaturated acyloxy-γ-butyrolactone derivative]
In the α- (meth) acryloyloxy-γ-butyrolactone derivative represented by the formula (1), R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms. . R ^b represents a group capable of leaving by an acid. R ¹ and R ² are the same or different and each represents a hydrocarbon group. R ¹ and R ² may be bonded to each other to form a ring together with adjacent carbon atoms. R ³ and R ⁴ are the same or different and each represents a hydrogen atom or a hydrocarbon group.

The halogen atom in R ^a includes a fluorine, chlorine, bromine atom and the like. Examples of the alkyl group having 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, and hexyl groups. Examples of the haloalkyl group having 1 to 6 carbon atoms include groups in which at least one hydrogen atom of the alkyl group having 1 to 6 carbon atoms is substituted with a fluorine atom, such as monofluoromethyl, difluoromethyl, trifluoromethyl, 2,2 , 2-trifluoroethyl, tetrafluoroethyl, 2,2,3,3,3-tetrafluoropropyl group and the like. R ^a is particularly preferably a hydrogen atom or a methyl group.

The group capable of leaving by the acid in the R ^b, may be a group causing desorbed with free carboxyl groups by the action of an acid generated from a photoacid generator by exposure, for example, the R ^b position adjacent A hydrocarbon group (tertiary hydrocarbon group) which has a tertiary carbon atom at the bonding site with an oxygen atom and may have a substituent, 2-tetrahydrofuranyl group, 2-tetrahydropyranyl group, 2 -An oxepanyl group etc. are mentioned. Examples of the tertiary hydrocarbon group include a t-butyl group, a t-amyl group, a 2-methyladamantan-2-yl group, and a (1-methyl-1-adamantyl) ethyl group. Examples of the substituent that the tertiary hydrocarbon group may have include, for example, a halogen atom, an alkyl group (eg, a C _1-4 alkyl group), a hydroxyl group that may be protected with a protecting group, oxo And a carboxyl group which may be protected with a protecting group.

The hydrocarbon group in R ¹ , R ² , R ³ and R ⁴ includes an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which two or more of these are bonded. Examples of the aliphatic hydrocarbon group include linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, hexyl, and octyl groups (C _{1- 8} alkyl groups); linear or branched alkenyl groups such as allyl groups (C _2-8 alkenyl groups, etc.); linear or branched alkynyl groups such as propynyl groups (C _2-8 alkynyl) Group, etc.). Examples of the alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclopentyl, and cyclohexyl groups (3 to 8 membered cycloalkyl groups); cycloalkenyl groups such as cyclopentenyl and cyclohexenyl groups (3 to 8 members). Cycloalkenyl groups and the like); bridged carbocyclic groups such as adamantyl and norbornyl groups (C _4-20 bridged carbocyclic groups and the like) and the like. Examples of the aromatic hydrocarbon group include C _6-14 aromatic hydrocarbon groups such as phenyl and naphthyl groups. Examples of the group in which an aliphatic hydrocarbon group and an aromatic hydrocarbon group are bonded include benzyl and 2-phenylethyl groups. Of the above hydrocarbon groups, linear or branched C _1-4 alkyl groups such as methyl, ethyl, propyl and isopropyl groups are particularly preferred.

These hydrocarbon groups are protected with alkyl groups (C _1-4 alkyl groups, etc.), haloalkyl groups (C _1-4 haloalkyl groups, etc.), halogen atoms, hydroxyl groups that may be protected with protecting groups, and protecting groups. It may have a substituent such as a hydroxymethyl group which may be protected, a carboxyl group which may be protected with a protecting group, or an oxo group. As the protecting group, a protecting group conventionally used in the field of organic synthesis can be used.

Examples of the ring formed by combining R ¹ and R ² together with adjacent carbon atoms include cycloalkane rings such as cyclopropane ring, cyclopentane ring, cyclohexane ring, cyclooctane ring (3- to 8-membered cycloalkane ring). Etc.); cycloalkene rings such as cyclohexene rings (3- to 8-membered cycloalkene rings etc.); bridged carbocycles such as adamantane rings and norbornane rings (C _4-20 bridged carbocycles etc.) and the like. These rings may have the same substituents as described above.

R ¹ and R ² are preferably a C _1-6 alkyl group, particularly a C _1-4 alkyl group such as a methyl group. It is also preferred that R ¹ and R ² are bonded to each other to form a 3- to 8-membered cycloalkane ring with adjacent carbon atoms. R ³ and R ⁴ are preferably a hydrogen atom or a C _1-6 alkyl group, particularly preferably a hydrogen atom or a C _1-4 alkyl group such as a methyl group.

  Representative examples of the α-unsaturated acyloxy-γ-butyrolactone derivative represented by the formula (1) include, for example, β- (t-butyloxycarbonyl) -α- (meth) acryloyloxy-γ, γ-dimethyl. -Γ-butyrolactone, β- (t-butyloxycarbonyl) -γ-ethyl-α- (meth) acryloyloxy-γ-methyl-γ-butyrolactone, β- (t-butyloxycarbonyl) -γ, γ-diethyl -Α- (meth) acryloyloxy-γ-butyrolactone, β- (t-butyloxycarbonyl) -α- (meth) acryloyloxy-γ-methyl-γ-propyl-γ-butyrolactone, β- (t-butyloxy Carbonyl) -γ-ethyl-α- (meth) acryloyloxy-γ-propyl-γ-butyrolactone, β- (t-butyloxycarbonyl) -α- (Meth) acryloyloxy-γ, γ-dipropyl-γ-butyrolactone, γ-butyl-β- (t-butyloxycarbonyl) -α- (meth) acryloyloxy-γ-methyl-γ-butyrolactone, 4- (t -Butyloxycarbonyl) -3- (meth) acryloyloxy-2-oxo-1-oxaspiro [4.4] nonane, 4- (t-butyloxycarbonyl) -3- (meth) acryloyloxy-2-oxo- 1-oxaspiro [4.5] decane and the like can be mentioned.

（式中、Ｒ^a、Ｒ^b、Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴は前記に同じ。Ｙはハロゲン原子を示す） The α-unsaturated acyloxy-γ-butyrolactone derivative represented by the formula (1) can be produced, for example, according to the following reaction process formula.

(Wherein, R ^a , R ^b , R ¹ , R ² , R ³ , R ⁴ are the same as above, Y represents a halogen atom)

  That is, an unsaturated dicarboxylic acid diester represented by the formula (2) and a secondary alcohol represented by the formula (3) are mixed with oxygen in the presence of an imide compound catalyst having a cyclic imide skeleton and a metal promoter. By reacting, an α-hydroxy-β-substituted oxycarbonyl-γ-butyrolactone derivative represented by the formula (4) is obtained, and then this compound and the unsaturated carboxylic acid halide represented by the formula (5) are used as a base. The α-unsaturated acyloxy-γ-butyrolactone derivative represented by the formula (1) can be obtained by reacting in the presence of.

  The reaction of the unsaturated carboxylic acid diester represented by the formula (2) and the alcohol represented by the formula (3) is usually performed in an organic solvent. Examples of the organic solvent include organic acids such as acetic acid and propionic acid; nitriles such as acetonitrile and benzonitrile; amides such as dimethylformamide; aliphatic hydrocarbons such as hexane; halogenation such as dichloromethane and trifluoromethylbenzene Hydrocarbons; nitro compounds such as nitrobenzene; esters such as ethyl acetate; mixed solvents thereof and the like can be used. The ratio of the compound represented by the formula (2) and the compound represented by the formula (3) is not particularly limited. For example, the compound represented by the formula (3) is converted into the compound represented by the formula (2). It is used 2 to 50 mole times the amount.

  As the imide compound catalyst, a known catalyst used in the oxidation reaction, such as N-hydroxyphthalimide, can be used. The usage-amount of an imide compound catalyst is 0.0001-1 mol with respect to 1 mol of compounds represented by Formula (2), Preferably it is 0.01-0.5 mol. Examples of the metal promoter include cobalt compounds such as cobalt acetate and cobalt acetylacetonate; manganese compounds such as manganese acetate and manganese acetylacetonate; and mixtures thereof. The usage-amount of a metal promoter is 0.0001-0.5 mol with respect to 1 mol of compounds represented by Formula (2), Preferably it is 0.001-0.2 mol.

  Molecular oxygen can be used as oxygen. As molecular oxygen, pure oxygen may be used, or oxygen diluted with an inert gas such as nitrogen, air, or the like may be used. The reaction temperature is, for example, about 0 to 170 ° C. The reaction may be carried out at normal pressure or under reduced pressure or increased pressure. The reaction method is not particularly limited, and may be any of batch type, semi-batch type, continuous type and the like. The reaction can also be carried out in stages. After completion of the reaction, the reaction product can be separated and purified by separation means such as filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography and the like.

  Reaction of the compound represented by Formula (4) and the compound represented by Formula (5) is normally performed in an organic solvent. Examples of the organic solvent that can be used include ethers such as tetrahydrofuran; hydrocarbons such as toluene; halogenated hydrocarbons such as dichloromethane; and mixed solvents thereof. As a halogen atom in Y in Formula (5), a chlorine atom, a bromine atom, etc. are mentioned, for example. The ratio of the compound represented by the formula (4) and the compound represented by the formula (5) is not particularly limited, but the amount of the compound represented by the formula (5) is usually used in the formula (4). It is 0.8-2 mol with respect to 1 mol of compounds represented, Preferably it is about 1-1.3 mol.

  Examples of the base include organic bases such as triethylamine and pyridine; inorganic bases such as sodium hydroxide. The usage-amount of a base is 1-1.5 mol with respect to 1 mol of compounds represented by Formula (4), for example, Preferably it is about 1-1.2 mol. In order to suppress polymerization of raw materials and products, a polymerization inhibitor may be present in the reaction system. The reaction temperature is, for example, -10 ° C to 100 ° C, preferably about 0 to 50 ° C. The reaction method is not particularly limited, and may be any of batch type, semi-batch type, continuous type and the like. After completion of the reaction, the reaction product [compound represented by formula (1)] can be separated and purified by separation means such as filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography and the like.

[Polymer compound]
The polymer compound of the present invention has at least one monomer unit (repeating unit) represented by the formula (I) as a structural unit constituting the polymer molecule (hereinafter sometimes referred to as “monomer unit 1”). Is included. Since the monomer unit 1 has an acid-eliminable group that is eliminated by the action of an acid to generate a carboxyl group, it functions as an alkali-soluble unit that solubilizes the resin during alkali development. Moreover, since it has a highly hydrophilic lactone ring, it functions as an adhesion-imparting unit that enhances adhesion to the substrate. Furthermore, since it has a highly polar lactone skeleton, it has a high affinity with a monomer that imparts high polar substrate adhesion, and when copolymerized with the monomer, each monomer unit is not unevenly distributed. A copolymer resin having a high composition uniformity that is uniformly incorporated in the molecule is obtained. Therefore, the production | generation of the polymer molecule | numerator which does not contain an alkali-soluble unit can also be prevented. Therefore, in the semiconductor manufacturing process, the line edge roughness can be greatly improved, and a fine pattern can be formed with high accuracy. Since the polymer compound of the present invention has various functions necessary as a photoresist in a well-balanced manner, the polymer compound further has a monomer unit [represented by the formula (I) having a group that is partially eliminated by acid and becomes alkali-soluble. Monomer units capable of imparting adhesion to the substrate [excluding monomer units represented by formula (I)] (for example, monomer units containing a lactone skeleton and / or hydroxyl groups, mercapto It is preferable to include a monomer unit having an alicyclic skeleton having a group or a carboxyl group.

  In a preferred embodiment of the present invention, at least one monomer unit represented by the formula (I) and at least one monomer unit (repeating unit) selected from the formulas (IIa) to (IIh) (hereinafter, "Sometimes referred to as" monomer unit 2 ").

R ^a in formulas (IIa) to (IIh) is the same as described above. In the formula (IIa), the hydrocarbon having 1 to 8 carbon atoms in R ⁵ and R ⁶ is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, pentyl, isopentyl, 1-methylbutyl, 1-ethyl. C _1-8 alkyl groups such as propyl, hexyl, isohexyl, 1-methylpentyl, 1-ethylbutyl, heptyl, 1-methylhexyl, octyl, 1-methylheptyl group; cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl A C _3-8 cycloalkyl group such as a group; and a phenyl group. Among these, C _1-3 alkyl groups such as methyl, ethyl, and isopropyl groups are preferable.

In the formula (IId), examples of the “hydrocarbon group having a tertiary carbon atom at the bonding site with the oxygen atom represented by the formula” in R ¹⁶ include a t-butyl group and a t-amyl group. It is done. These hydrocarbon groups may have a substituent.

In formula (IIh), the alkyl group for R ²³ and R ²⁴ is a linear or branched alkyl group such as methyl, ethyl, propyl, isopropyl, sec-butyl, pentyl, hexyl group (C _1-6 Alkyl group, etc.). The fluoroalkyl group includes a group in which at least one hydrogen atom of the alkyl group is substituted with a fluorine atom, such as monofluoromethyl, difluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, tetrafluoro Examples include ethyl, 2,2,3,3,3-tetrafluoropropyl group. R ²³ and R ²⁴ are particularly preferably a hydrogen atom, a C _1-3 alkyl group, a C _1-3 fluoroalkyl group, or the like.

In the formula (IIh), examples of the organic group for R ²⁵ include a group containing a hydrocarbon group and / or a heterocyclic group. Examples of the hydrocarbon group include the same hydrocarbon groups as in R ¹ and R ² . Examples of the heterocyclic group include heterocyclic groups containing at least one heteroatom selected from an oxygen atom, a sulfur atom and a nitrogen atom.

Preferred organic groups include C _1-8 alkyl groups, organic groups containing a cyclic skeleton, and the like. The “ring” constituting the cyclic skeleton includes a monocyclic or polycyclic non-aromatic or aromatic carbocyclic or heterocyclic ring. Of these, monocyclic or polycyclic non-aromatic carbocycles and lactone rings (which may be condensed with non-aromatic carbocycles) are particularly preferable. Examples of the monocyclic non-aromatic carbocycle include a cycloalkane ring having about 3 to 15 members such as a cyclopentane ring and a cyclohexane ring.

Examples of the polycyclic non-aromatic carbocycle (bridged carbocycle) include, for example, an adamantane ring, norbornane ring, norbornene ring, bornane ring, isobornane ring, adamantane ring; norbornane ring, norbornene ring, bornane ring, isobornane ring, tricyclo [5.2.1.0 ^2,6 ] decane ring, tetracyclo [4.4.0.1 ^2,5 . ^1,7,10 ] ring containing norbornane ring or norbornene ring such as dodecane ring; perhydroindene ring, decalin ring (perhydronaphthalene ring), perhydrofluorene ring (tricyclo [7.4.0.0 ^3,8 ] Tridecane ring), a ring in which a polycyclic aromatic condensed ring such as perhydroanthracene ring is hydrogenated (preferably a fully hydrogenated ring); a tricyclo [4.2.2.1 ^2,5 ] undecane ring, etc. And a bridged carbocyclic ring (for example, a bridged carbocyclic ring having about 6 to 20 carbon atoms). Examples of the lactone ring include a γ-butyrolactone ring, 4-oxatricyclo [4.3.1.1 ^3,8 ] undecan-5-one ring, and 4-oxatricyclo [4.2.1.0 ^{3. , 7} ] nonan-5-one ring, 4-oxatricyclo [5.2.1.0 ^2,6 ] decan-5-one ring, and the like.

The ring constituting the cyclic skeleton includes an alkyl group such as a methyl group (eg, a C _1-4 alkyl group), a haloalkyl group such as a trifluoromethyl group (eg, a C _1-4 haloalkyl group), a chlorine atom Or a halogen atom such as a fluorine atom, a hydroxyl group that may be protected with a protective group, a hydroxyalkyl group that may be protected with a protective group, a mercapto group that may be protected with a protective group, or a protective group. It may have a substituent such as a carboxyl group which may be protected, an amino group which may be protected with a protecting group, and a sulfonic acid group which may be protected with a protecting group. As the protecting group, a protecting group conventionally used in the field of organic synthesis can be used.

The ring constituting the cyclic skeleton may be directly bonded to an oxygen atom (oxygen atom adjacent to R ²⁵ ) shown in the formula (IIh) or may be bonded via a linking group. . Examples of the linking group include a linear or branched alkylene group such as methylene, methylmethylene, dimethylmethylene, ethylene, propylene, and trimethylene group; a carbonyl group; an oxygen atom (ether bond; —O—); an oxycarbonyl group ( An ester bond; —COO—); an aminocarbonyl group (amide bond; —CONH—); and a group in which a plurality of these are bonded.

  The monomer unit represented by the formula (IIa) is desorbed from the carboxylic acid moiety in which the site containing the adamantane skeleton is bonded to the main chain by an acid to generate a free carboxyl group. In the monomer unit represented by the formula (IIb), a carboxyl group protected by a protecting group bonded to an adamantane skeleton is deprotected by an acid to generate a free carboxyl group. The monomer unit represented by the formula (IIc) generates a free carboxyl group by elimination from the carboxylic acid moiety in which the adamantane skeleton is bonded to the main chain by an acid. Furthermore, in the monomer units represented by the formulas (IId), (IIe), (IIf), (IIg) and (IIh), the carboxylic acid ester moiety is decomposed and eliminated by an acid to generate a free carboxyl group. Therefore, the monomer unit 2 functions as an alkali-soluble unit that solubilizes the resin during alkali development.

The monomer units represented by the formulas (IIa), (IIb), (IIc) and (IIg), and the monomer unit in which R ²⁵ is a group containing a non-aromatic carbocycle in the formula (IIh) Since it has a cyclic carbon skeleton, it has the characteristics of excellent transparency and extremely high etching resistance. In addition, in the formula (IIa), a monomer unit in which at least one of R ^{7 to} R ⁹ is a hydroxyl group, a monomer unit represented by the formula (IIf), and a group in which R ^{25 in the} formula (IIh) contains a lactone ring The monomer unit is highly hydrophilic and also has an adhesive function.

  In a preferred embodiment of the polymer compound of the present invention, in addition to the monomer unit 1 or the monomer units 1 and 2, at least one monomer selected from the monomer units represented by the formulas (IIIa) to (IIIh) A unit (repeating unit) (hereinafter sometimes referred to as “monomer unit 3”) may be included.

R ^a in formulas (IIIa) to (IIIh) is the same as described above. In the formula (IIIb), the direction of the —CO—O— group in X ^{1 to} X ³ is not limited. In the formula (IIIe), the linear, branched, cyclic or bridged cyclic hydrocarbon group (bridged cyclic group) having 1 to 20 carbon atoms in R ³⁹ is methyl, ethyl, propyl, isopropyl. , Butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, decyl, dodecyl, tetradecyl, octadecyl and the like linear or branched aliphatic hydrocarbon groups (particularly alkyl groups) such as cyclopentyl; Cycloalkyl, cycloalkenyl group such as cyclohexyl, cyclooctyl, cyclododecyl group, etc .; perhydroindene ring, perhydrofluorene ring, perhydronaphthalene ring (decalin ring), perhydroanthracene ring, norbornane ring , Norbornene ring, pinane ring, bornane ring, isobornylane ring, tricyclo [5. 2.1.0 ^2,6 ] decane ring, tetracyclo [4.4.0.1 ^2,5 . 1 ^{7, 10} ] bridged cyclic hydrocarbon group having 6 to 20 carbon atoms (bridged cyclic hydrocarbon group) corresponding to dodecane ring, etc .; tricyclo [5.2.1.0 ^2,6 ] decylmethyl group, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodecylmethyl group, 2-norbornylmethyl group and the like, and the like groups bonded to each of the hydrocarbon groups. These hydrocarbon groups include an alkyl group, a halogen atom, a hydroxyl group that may be protected with a protecting group, a hydroxymethyl group that may be protected with a protecting group, and a carboxyl group that may be protected with a protecting group ( For example, it has a substituent such as a carboxyl group, a t-butyloxycarbonyl group, a 2-tetrahydrofuranyloxycarbonyl group, a 2-tetrahydropyranyloxycarbonyl group, a 2-oxepanyloxycarbonyl group, and an oxo group. May be. As the protecting group, a protecting group commonly used in the field of organic synthesis can be used.

The monomer unit represented by the formula (IIIa) has a function of improving adhesion to a substrate because a highly hydrophilic group (hydroxyl group, carboxyl group, oxo group) is bonded to the adamantane skeleton. In addition, formulas (IIIa), (IIIb) (wherein X ^{1 to} X ³ are all methylene groups, etc.), (IIIc), (IIIe) (where R ³⁹ is a cyclic or bridged cyclic hydrocarbon group), Since the monomer units represented by (IIIg) and (IIIh) have an alicyclic carbon skeleton, they contribute to improvements in transparency and etching resistance. A monomer unit having a lactone skeleton represented by formula (IIIb) (wherein at least one of X ^{1 to} X ³ is a —CO—O— group), (IIIc), (IIId) and (IIIg), ) (In which R ³⁹ is a hydrogen atom), (IIIf), (IIIh) (in which R ⁴⁴ is a hydroxyl group, a hydroxymethyl group or a carboxyl group) the monomer unit contains a hydrophilic group , Has an adhesion imparting function. Thus, since these monomer units can give various functions based on their structures, incorporation of each of the above monomer units into the polymer makes it possible to finely balance the various properties required as a resist resin depending on the application. Can be adjusted. In addition, in order to adjust said various characteristics, the high molecular compound of this invention may contain the monomer unit other than the above as needed.

  In the polymer compound of the present invention, the content of the monomer unit 1 is, for example, 10 to 90 mol%, preferably 20 to 70 mol%, more preferably 30 to 50 mol, based on the entire monomer unit constituting the polymer. %. Moreover, in a preferable high molecular compound, the monomer unit 2 is contained, for example with respect to the whole monomer unit which comprises a polymer, for example, 0-50 mol%, Preferably it is 0-30 mol%, More preferably, about 0-10 mol% is contained. . Further, the content of the monomer unit 3 in the polymer compound containing the monomer unit 3 is, for example, 10 to 90 mol%, preferably 20 to 80 mol%, more preferably 30 with respect to the entire monomer unit constituting the polymer. It is about -70 mol%.

Among the combinations of the above monomer units in the polymer compound of the present invention, the following are particularly preferable combinations.
(1) at least one monomer unit represented by formula (I) and at least one monomer unit selected from formulas (IIa) to (IIh) (in particular, formulas (IIa), (IIb) and (At least one monomer unit selected from (IIc))

(2) at least one monomer unit represented by formula (I) and at least one monomer unit selected from formulas (IIa) to (IIh) (in particular, formulas (IIa), (IIb) and (IIc) And at least one monomer unit selected from formulas (IIIa) to (IIIh) (especially at least selected from formulas (IIIa), (IIIf) and (IIIh)) Combination with one monomer unit)

(3) at least one monomer unit represented by formula (I) and at least one monomer unit selected from formulas (IIIa) to (IIIh) (particularly formulas (IIIa), (IIIf) and (At least one monomer unit selected from (IIIh))

The polymer compound of the present invention has a solubility parameter value (“SP value”) of 19.5 (J / cm ³ ) according to the method of Fedors [see Polym. Eng. Sci., 14, 147 (1974)] ^{1 / It} is preferably in the range of ^{2 to} 24.5 (J / cm ³ ) ^1/2 . A resist coating film formed by applying a resin composition for a photoresist containing a polymer compound having such a solubility parameter to a semiconductor substrate (silicon wafer) is excellent in adhesion (adhesion) to the substrate and alkali. A pattern with high resolution can be formed by development. When the SP value is lower than 19.5 (J / cm ³ ) ^1/2 , the adhesion to the substrate is lowered, and the problem that the pattern is not peeled off by development is likely to occur. On the other hand, if the SP value is larger than 24.5 (J / cm ³ ) ^1/2 , it tends to be difficult to be applied by being repelled by the substrate, and the affinity for an alkali developer is increased. The resolution contrast is likely to deteriorate due to poor solubility contrast between the unexposed areas and the unexposed areas.

  The weight average molecular weight (Mw) of the polymer compound is, for example, about 5000 to 50000, preferably about 7000 to 20000, and the molecular weight distribution (Mw / Mn) is, for example, about 1.8 to 3.5. In addition, said Mn shows a number average molecular weight, and both Mn and Mw are values of polystyrene conversion.

  Each of the monomer units represented by the formulas (IIg), (IIIf), (IIIg) and (IIIh) has a corresponding ethylenically unsaturated compound as a (co) monomer, and the formula (I), (IIa ) To (IIf), (IIh), and (IIIa) to (IIIe), each monomer unit can be formed by subjecting the corresponding (meth) acrylic acid or its ester as a (co) monomer to polymerization. .

[Monomer unit of formula (I)]
The monomer corresponding to the monomer unit of the formula (I) is represented by the formula (1). The monomers represented by the formula (1) can be used alone or in combination of two or more. Moreover, although a stereoisomer exists in the compound represented by Formula (1), in this invention, only one stereoisomer may be used and the mixture of several stereoisomers may be used.

[Monomer unit of formula (IIa)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIa), there may be mentioned the following compounds. 1- (1- (meth) acryloyloxy-1-methylethyl) adamantane, 1-hydroxy-3- (1- (meth) acryloyloxy-1-methylethyl) adamantane, 1- (1-ethyl-1- ( (Meth) acryloyloxypropyl) adamantane, 1-hydroxy-3- (1-ethyl-1- (meth) acryloyloxypropyl) adamantane, 1- (1- (meth) acryloyloxy-1-methylpropyl) adamantane, 1- Hydroxy-3- (1- (meth) acryloyloxy-1-methylpropyl) adamantane, 1- (1- (meth) acryloyloxy-1,2-dimethylpropyl) adamantane, 1-hydroxy-3- (1- ( (Meth) acryloyloxy-1,2-dimethylpropyl) adamantane, 1,3-dihydroxy -5- (1- (meth) acryloyloxy-1-methylethyl) adamantane, 1- (1-ethyl-1- (meth) acryloyloxypropyl) -3,5-dihydroxyadamantane, 1,3-dihydroxy-5 -(1- (meth) acryloyloxy-1-methylpropyl) adamantane, 1,3-dihydroxy-5- (1- (meth) acryloyloxy-1,2-dimethylpropyl) adamantane.

[Monomer unit of formula (IIb)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIb), there may be mentioned the following compounds. 1-t-butoxycarbonyl-3- (meth) acryloyloxyadamantane, 1,3-bis (t-butoxycarbonyl) -5- (meth) acryloyloxyadamantane, 1-t-butoxycarbonyl-3-hydroxy-5 (Meth) acryloyloxyadamantane, 1- (2-tetrahydropyranyloxycarbonyl) -3- (meth) acryloyloxyadamantane, 1,3-bis (2-tetrahydropyranyloxycarbonyl) -5- (meth) acryloyloxy Adamantane, 1-hydroxy-3- (2-tetrahydropyranyloxycarbonyl) -5- (meth) acryloyloxyadamantane.

[Monomer unit of formula (IIc)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIc), there may be mentioned the following compounds. 2- (meth) acryloyloxy-2-methyladamantane, 1-hydroxy-2- (meth) acryloyloxy-2-methyladamantane, 5-hydroxy-2- (meth) acryloyloxy-2-methyladamantane, 1,3 -Dihydroxy-2- (meth) acryloyloxy-2-methyladamantane, 1,5-dihydroxy-2- (meth) acryloyloxy-2-methyladamantane, 1,3-dihydroxy-6- (meth) acryloyloxy-6 -Methyl adamantane, 2- (meth) acryloyloxy-2-ethyladamantane, 1-hydroxy-2- (meth) acryloyloxy-2-ethyladamantane, 5-hydroxy-2- (meth) acryloyloxy-2-ethyladamantane 1,3-dihydroxy-2- (meth) ac Liloyloxy-2-ethyladamantane, 1,5-dihydroxy-2- (meth) acryloyloxy-2-ethyladamantane, 1,3-dihydroxy-6- (meth) acryloyloxy-6-ethyladamantane.

[Monomer unit of formula (IId)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IId), there may be mentioned the following compounds. t-Butyl (meth) acrylate.

[Monomer unit of formula (IIe)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIe), there may be mentioned the following compounds. 2-tetrahydropyranyl (meth) acrylate, 2-tetrahydrofuranyl (meth) acrylate.

[Monomer unit of formula (IIf)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIf), there may be mentioned the following compounds. β- (meth) acryloyloxy-γ-butyrolactone, β- (meth) acryloyloxy-α, α-dimethyl-γ-butyrolactone, β- (meth) acryloyloxy-γ, γ-dimethyl-γ-butyrolactone, β- (Meth) acryloyloxy-α, α, β-trimethyl-γ-butyrolactone, β- (meth) acryloyloxy-β, γ, γ-trimethyl-γ-butyrolactone, β- (meth) acryloyloxy-α, α, β, γ, γ-pentamethyl-γ-butyrolactone.

[Monomer unit of formula (IIg)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIg), there may be mentioned the following compounds. 5-t-butoxycarbonylnorbornene, 9-t-butoxycarbonyltetracyclo [6.2.1.1 ^3,6 . 0 ^2,7 ] dodec-4-ene, 5- (2-tetrahydropyranyloxycarbonyl) norbornene, 9- (2-tetrahydropyranyloxycarbonyl) tetracyclo [6.2.1.1 ^3,6 . 0 ^2,7 ] dodec-4-ene.

[Monomer unit of formula (IIh)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIh), there may be mentioned the following compounds. 1- (adamantan-1-yloxy) ethyl (meth) acrylate, 1- (adamantan-1-ylmethoxy) ethyl (meth) acrylate, 1- [2- (adamantan-1-yl) ethoxy] ethyl (meth) acrylate, 1- (3-hydroxyadamantan-1-yloxy) ethyl (meth) acrylate, 1- (norbornan-2-yloxy) ethyl (meth) acrylate, 1- (norbornan-2-ylmethoxy) ethyl (meth) acrylate, 1- (2-methylnorbornan-2-yloxy) ethyl (meth) acrylate, 1- [1- (norbornan-2-yl) -1-methylethoxy] ethyl (meth) acrylate, 1- (3-methylnorbornane-2- Ylmethoxy) ethyl (meth) acrylate, 1- (bornyloxy) ) Ethyl (meth) acrylate, 1- (isobornyloxycarbonyl) ethyl (meth) acrylate; 1- [1- (meth) acryloyloxy ethoxy] -4-oxa-tricyclo [4.3.1.1 ^{3, 8} ] Undecan-5-one, 2- [1- (meth) acryloyloxyethoxy] -4-oxatricyclo [4.2.1.0 ^3,7 ] nonan-5-one, 8- [1- (meta ) Acrylyloxyethoxy] -4-oxatricyclo [5.2.1.0 ^2,6 ] decan-5-one, 9- [1- (meth) acryloyloxyethoxy] -4-oxatricyclo [5. 2.1.0 ^2,6 ] decan-5-one, α- [1- (meth) acryloyloxyethoxy] -γ, γ-dimethyl-γ-butyrolactone, 3- [1- (meth) acryloyloxyethoxy] -2-oxo-1- Oxaspiro [4.5] decane, α- [1- (meth) acryloyloxyethoxy] -γ-butyrolactone, α- [1- (meth) acryloyloxyethoxy] -α, γ, γ-trimethyl-γ-butyrolactone, α- [1- (Meth) acryloyloxyethoxy] -β, β-dimethyl-γ-butyrolactone.

[Monomer unit of formula (IIIa)]
Typical compounds of the monomer corresponding to the monomer unit of the formula (IIIa) include the following compounds. 1-hydroxy-3- (meth) acryloyloxyadamantane, 1,3-dihydroxy-5- (meth) acryloyloxyadamantane, 1-carboxy-3- (meth) acryloyloxyadamantane, 1,3-dicarboxy-5 (Meth) acryloyloxyadamantane, 1-carboxy-3-hydroxy-5- (meth) acryloyloxyadamantane, 1- (meth) acryloyloxy-4-oxoadamantane, 3-hydroxy-1- (meth) acryloyloxy-4 -Oxoadamantane, 7-hydroxy-1- (meth) acryloyloxy-4-oxoadamantane.

[Monomer unit of formula (IIIb)]
As typical examples of the monomer corresponding to the monomer unit of the formula (IIIb), there may be mentioned the following compounds. 1- (meth) acryloyloxy-4-oxatricyclo [4.3.1.1 ^3,8 ] undecan-5-one, 1- (meth) acryloyloxy-4,7-dioxatricyclo [4. 4.1.1 ^3,9 ] dodecane-5,8-dione, 1- (meth) acryloyloxy-4,8-dioxatricyclo [4.4.1.1 ^3,9 ] dodecane-5,7 -Dione, 1- (meth) acryloyloxy-5,7-dioxatricyclo [4.4.1.1 ^3,9 ] dodecane-4,8-dione.

[Monomer unit of formula (IIIc)]
Typical examples of the monomer that forms the monomer unit of the formula (IIIc) include the following compounds. 2- (Meth) acryloyloxy-4-oxatricyclo [4.2.1.0 ^3,7 ] nonan-5-one, 2- (meth) acryloyloxy-2-methyl-4-oxatricyclo [4 .2.1.0 ^3,7 ] nonan-5-one.

[Monomer unit of formula (IIId)]
Typical examples of the monomer forming the monomer unit of the formula (IIId) include the following compounds. α- (meth) acryloyloxy-γ-butyrolactone, α- (meth) acryloyloxy-α-methyl-γ-butyrolactone, α- (meth) acryloyloxy-β, β-dimethyl-γ-butyrolactone, α- (meta ) Acrylyloxy-α, β, β-trimethyl-γ-butyrolactone, α- (meth) acryloyloxy-γ, γ-dimethyl-γ-butyrolactone, α- (meth) acryloyloxy-α, γ, γ-trimethyl- γ-butyrolactone, α- (meth) acryloyloxy-β, β, γ, γ-tetramethyl-γ-butyrolactone, α- (meth) acryloyloxy-α, β, β, γ, γ-pentamethyl-γ-butyrolactone .

[Monomer unit of formula (IIIe)]
Typical examples of the monomer forming the monomer unit of the formula (IIIe) include the following compounds. (Meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, decahydro (meth) acrylate Naphthyl, norbornyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dimethyladamantyl (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decyl (meth) acrylate , Tetracyclo (meth) acrylate [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecyl. A compound in which a substituent such as a hydroxy group, a hydroxymethyl group, a carboxyl group, or an oxo group is bonded to a group corresponding to R ³⁷ of these compounds is also preferable.

[Monomer unit of formula (IIIf)]
The monomer forming the monomer unit of the formula (IIIf) includes maleic anhydride.

[Monomer unit of formula (IIIg)]
Typical examples of the monomer that forms the monomer unit of the formula (IIIg) include the following compounds. 4-oxatricyclo [5.2.1.0 ^2,6 ] decan-8-en-5-one, 3-oxatricyclo [5.2.1.0 ^2,6 ] decan-8-ene- 4-one, 5-oxatricyclo [6.2.1.0 ^2,7 ] undecan-9-en-6-one, 4-oxatricyclo [6.2.1.0 ^2,7 ] undecane- 9-en-5-one, 4-oxapentacyclo [6.5.1.1 ^9,12 . 0 ^2,6 . 0 ^8,13 ] pentadecan-10-en-5-one, 3-oxapentacyclo [6.5.1.1 ^9,12 . 0 ^2,6 . 0 ^8,13] pentadecane-10-en-4-one, 5-oxa penta cyclo [6.6.1.1 ^{10, 13.} 0 ^2,7 . 0 ^9,14] hexadecane-11-en-6-one, 4-oxa-penta cyclo [6.6.1.1 ^{10, 13.} 0 ^2,7 . 0 ^9,14 ] Hexadecan-11-en-5-one.

[Monomer unit of formula (IIIh)]
As typical examples of the monomer forming the monomer unit of the formula (IIIh), there may be mentioned the following compounds. Norbornene, 5-hydroxy-2-norbornene.

  In obtaining the polymer compound of the present invention, the polymerization of the monomer mixture is carried out by a conventional method used for producing an acrylic polymer, such as solution polymerization, bulk polymerization, suspension polymerization, bulk-suspension polymerization, and emulsion polymerization. Although it can be performed, solution polymerization is particularly preferred. Furthermore, drop polymerization is preferable among solution polymerization. Specifically, for example, (i) a monomer solution previously dissolved in an organic solvent and a polymerization initiator solution dissolved in an organic solvent are prepared in an organic solvent kept at a constant temperature. A method in which the monomer solution and the polymerization initiator solution are respectively dropped, and (ii) a method in which a mixed solution in which the monomer and the polymerization initiator are dissolved in an organic solvent is dropped into an organic solvent maintained at a constant temperature. (Iii) A monomer solution previously dissolved in an organic solvent and a polymerization initiator solution dissolved in the organic solvent are respectively prepared, and the polymerization initiator solution is dropped into the monomer solution maintained at a constant temperature. It is performed by a method or the like.

  As the polymerization solvent, a known solvent can be used. For example, ether (chain ether such as diethyl ether and glycol ether such as propylene glycol monomethyl ether, cyclic ether such as tetrahydrofuran and dioxane), ester (methyl acetate, ethyl acetate, Glycol ether esters such as butyl acetate, ethyl lactate, propylene glycol monomethyl ether acetate), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), amides (N, N-dimethylacetamide, N, N-dimethylformamide, etc.) ), Sulfoxide (dimethylsulfoxide, etc.), alcohol (methanol, ethanol, propanol, etc.), hydrocarbon (aromatic hydrocarbons such as benzene, toluene, xylene, etc.) Aliphatic hydrocarbons such as hexane, and alicyclic hydrocarbons such as cyclohexane), and mixtures of these solvents. Moreover, a well-known polymerization initiator can be used as a polymerization initiator. The polymerization temperature can be appropriately selected within a range of about 30 to 150 ° C., for example.

  The polymer obtained by polymerization can be purified by precipitation or reprecipitation. The precipitation or reprecipitation solvent may be either an organic solvent or water, or a mixed solvent. Examples of the organic solvent used as the precipitation or reprecipitation solvent include hydrocarbons (aliphatic hydrocarbons such as pentane, hexane, heptane, and octane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; aromatics such as benzene, toluene, and xylene. Aromatic hydrocarbons), halogenated hydrocarbons (halogenated aliphatic hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride; halogenated aromatic hydrocarbons such as chlorobenzene and dichlorobenzene), nitro compounds (nitromethane, nitroethane, etc.) , Nitrile (acetonitrile, benzonitrile, etc.), ether (chain ether such as diethyl ether, diisopropyl ether, dimethoxyethane; cyclic ether such as tetrahydrofuran, dioxane), ketone (acetone, methyl ethyl ketone) Diisobutyl ketone, etc.), ester (ethyl acetate, butyl acetate, etc.), carbonate (dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, etc.), alcohol (methanol, ethanol, propanol, isopropyl alcohol, butanol, etc.), carboxylic acid (acetic acid, etc.) Etc.), and mixed solvents containing these solvents.

  Among these, as the organic solvent used as the precipitation or reprecipitation solvent, a solvent containing at least a hydrocarbon (particularly an aliphatic hydrocarbon such as hexane) is preferable. In such a solvent containing at least hydrocarbon, the ratio of hydrocarbon (for example, aliphatic hydrocarbon such as hexane) and other solvent is, for example, the former / the latter (volume ratio; 25 ° C.) = 10/90 to 99 / 1, preferably the former / the latter (volume ratio; 25 ° C.) = 30/70 to 98/2, more preferably the former / the latter (volume ratio; 25 ° C.) = About 50/50 to 97/3.

  The resin composition for photoresists of the present invention contains the polymer compound of the present invention and a photoacid generator.

  Examples of the photoacid generator include conventional or known compounds that efficiently generate acid upon exposure, such as diazonium salts, iodonium salts (for example, diphenyliodohexafluorophosphate), sulfonium salts (for example, triphenylsulfonium hexafluoroantimony). Nates, triphenylsulfonium hexafluorophosphate, triphenylsulfonium methanesulfonate, etc.), sulfonate esters [eg 1-phenyl-1- (4-methylphenyl) sulfonyloxy-1-benzoylmethane, 1,2,3-tri Sulfonyloxymethylbenzene, 1,3-dinitro-2- (4-phenylsulfonyloxymethyl) benzene, 1-phenyl-1- (4-methylphenylsulfonyloxymethyl) -1-hydroxy-1-benzo Rumetan etc.], oxathiazole derivatives, s- triazine derivatives, disulfone derivatives (diphenyl sulfone) imide compound, an oxime sulfonate, a diazonaphthoquinone, and benzoin tosylate. These photoacid generators can be used alone or in combination of two or more.

  The amount of the photoacid generator used can be appropriately selected according to the strength of the acid generated by light irradiation, the ratio of each monomer unit (repeating unit) in the polymer compound, etc., for example, 100 parts by weight of the polymer compound On the other hand, it can be selected from a range of about 0.1 to 30 parts by weight, preferably 1 to 25 parts by weight, and more preferably about 2 to 20 parts by weight.

  The resin composition for photoresist includes alkali-soluble components such as alkali-soluble resins (for example, novolak resins, phenol resins, imide resins, carboxyl group-containing resins), colorants (for example, dyes), organic solvents (for example, Hydrocarbons, halogenated hydrocarbons, alcohols, esters, amides, ketones, ethers, cellosolves, carbitols, glycol ether esters, mixed solvents thereof, etc.) .

  This photoresist resin composition is applied onto a substrate or substrate, dried, and then exposed to light on a coating film (resist film) through a predetermined mask (or further subjected to post-exposure baking). By forming the latent image pattern and then developing it, a fine pattern can be formed with high accuracy.

  Examples of the base material or the substrate include a silicon wafer, metal, plastic, glass, and ceramic. The application of the photoresist resin composition can be performed using a conventional application means such as a spin coater, a dip coater, or a roller coater. The thickness of the coating film is, for example, about 0.01 to 20 μm, preferably about 0.05 to 2 μm.

For exposure, various wavelengths of light such as ultraviolet rays and X-rays can be used. For semiconductor resists, g-line, i-line, and excimer lasers (eg, XeCl, KrF, KrCl, ArF, ArCl, F) are generally used. ₂ , Kr ₂ , KrAr, Ar ₂ etc.). The exposure energy is, for example, about 0.1 to 1000 mJ / cm ² .

  An acid is generated from the photoacid generator by light irradiation, and this acid causes a protective group (leaving group) such as a carboxyl group of a monomer unit (alkali-soluble unit) having an acid leaving group of the polymer compound. Is rapidly eliminated, and carboxyl groups and the like that contribute to solubilization are generated. Therefore, a predetermined pattern can be accurately formed by development with water or an alkali developer.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In the chemical structural formula, tBu represents a t-butyl group.

Production Example 1 (Production of β-t-butyloxycarbonyl-α-hydroxy-γ, γ-dimethyl-γ-butyrolactone)
In a four-necked flask equipped with a Dimroth condenser, dry air inlet, and thermometer, di-t-butyl fumarate 297 g (1.3 mol), 2-propanol 781 g (13 mol), N-hydroxyphthalimide 84.8 g ( 0.52 mol), cobalt acetate (II) tetrahydrate 13.0 g (52 mmol) and acetonitrile 790 g were added, and the mixture was stirred at 50 ° C. for 6 hours while blowing 1 L of dry air every minute. The reaction solution was concentrated under reduced pressure, 1 L of p-xylene was added to the concentrated residue, and the mixture was stirred for 5 hours while heating to reflux. The reaction solution was concentrated under reduced pressure. The concentrated residue was purified by silica gel column chromatography, and 185 g (0.803 mol, 0.803 mol, β-t-butyloxycarbonyl-α-hydroxy-γ, γ-dimethyl-γ-butyrolactone represented by the following formula (6) A yield of 62% based on di-t-butyl fumarate) was obtained. The obtained material was a mixture of two stereoisomers, and the abundance ratio was approximately 1: 1.

[Spectral data of β-t-butyloxycarbonyl-α-hydroxy-γ, γ-dimethyl-γ-butyrolactone]
One stereoisomer
¹ H-NMR (CDCl ₃ ) δ: 1.49 (s, 9H), 1.52 (s, 3H), 1.58 (s, 3H), 3.19 (d, 1H), 3.53 (brs, 1H), 4.78 (d, 1H )
The other stereoisomer
¹ H-NMR (CDCl ₃ ) δ: 1.34 (s, 3H), 1.51 (s, 9H), 1.63 (s, 3H), 3.11 (d, 1H), 3.68 (brs, 1H), 4.94 (d, 1H )

Production Example 2 (Production of β-t-butyloxycarbonyl-α-methacryloyloxy-γ, γ-dimethyl-γ-butyrolactone)
In a two-necked flask equipped with a thermometer, β-t-butyloxycarbonyl-α-hydroxy-γ, γ-dimethyl-γ-butyrolactone 5.0 g (21.7 mmol), 4-methoxyphenol 1.3 mg, triethylamine 2.4 g (23.7 mmol) was dissolved in 50 ml of tetrahydrofuran. Under a nitrogen atmosphere, 2.5 g (23.9 mmol) of methacrylic acid chloride was slowly dropped while keeping the liquid temperature in the vicinity of 20 ° C. in a water bath, the water bath was removed, and the mixture was stirred at room temperature for 4 hours. Thereafter, 100 ml of water was added, and tetrahydrofuran was distilled off under reduced pressure. The concentrated solution was extracted twice with 100 ml of ethyl acetate, and the organic layer was washed with 100 ml of aqueous ammonium chloride solution, 100 ml of aqueous sodium chloride solution, 100 ml of 10 wt% aqueous sodium hydrogen carbonate solution and 100 ml of aqueous sodium chloride solution, and dried over anhydrous magnesium sulfate. Thereafter, the mixture was concentrated under reduced pressure to obtain a yellow viscous liquid. This was purified by silica gel column chromatography, and 3.67 g (12.3 mmol, β-t-butyloxycarbonyl-α-methacryloyloxy-γ, γ-dimethyl-γ-butyrolactone represented by the following formula (7) was collected. A white solid having a rate of 57%) was obtained. The obtained material was a mixture of two stereoisomers, and the abundance ratio was approximately 1: 1.

[Spectral data of β-t-butyloxycarbonyl-α-methacryloyloxy-γ, γ-dimethyl-γ-butyrolactone]
One stereoisomer
¹ H-NMR (CDCl ₃ ) δ: 1.41 (s, 3H), 1.49 (s, 9H), 1.68 (s, 3H), 1.97 (s, 3H), 3.34 (d, 1H), 5.67 (m, 1H ), 6.00 (d, 1H), 6.19 (s, 1H)
The other stereoisomer
¹ H-NMR (CDCl ₃ ) δ: 1.48 (s, 9H), 1.55 (s, 3H), 1.56 (s, 3H), 1.97 (s, 3H), 3.28 (d, 1H), 5.69-5.70 (m , 1H), 5.87 (d, 1H), 6.23 (s, 1H)

還流管、撹拌子、３方コックを備えた丸底フラスコに、窒素雰囲気下、プロピレングリコールモノメチルエーテルアセテート（ＰＧＭＥＡ）４１．６５ｇ、及びプロピレングリコールモノメチルエーテル（ＰＧＭＥ）１７．８５ｇを入れ、温度を１００℃に保ち、撹拌しながら、β−ｔ−ブチルオキシカルボニル−γ，γ−ジメチル−α−メタクリロイルオキシ−γ−ブチロラクトン１４．０１ｇ（４７．０ｍｍｏｌ）、９−メタクリロイルオキシ−２−オキサトリシクロ［４．２．１．０^4,8］ノナン−３−オン１０．４４ｇ（４７．０ｍｍｏｌ）、１−ヒドロキシ−３−メタクリロイルオキシアダマンタン５．５５ｇ（２３．５ｍｍｏｌ）、ジメチル ２，２′−アゾビスイソブチレート（開始剤：和光純薬工業製、商品名「Ｖ−６０１」）０．７５ｇ、ＰＧＭＥＡ７７．３５ｇ、及びＰＧＭＥ３３．１５ｇを混合したモノマー溶液を６時間かけて一定速度で滴下した。滴下終了後、さらに２時間撹拌を続けた。重合反応終了後、得られた反応溶液を孔径０．１μｍのフィルターで濾過した後、該反応溶液の７倍量のヘキサンと酢酸エチルの９：１（体積比；２５℃）混合液中に撹拌しながら滴下した。生じた沈殿物を濾別することにより、所望の樹脂２７．３ｇを得た。回収したポリマーをＧＰＣ（ゲルパーミエーションクロマトグラフィー）分析したところ、重量平均分子量（Ｍｗ）が８８００、分子量分布（Ｍｗ／Ｍｎ）が１．８２であった。 Example 1
Synthesis of resin with the following structure

In a round bottom flask equipped with a reflux tube, a stirring bar, and a three-way cock, 41.65 g of propylene glycol monomethyl ether acetate (PGMEA) and 17.85 g of propylene glycol monomethyl ether (PGME) are placed under a nitrogen atmosphere, and the temperature is set to 100. While maintaining the temperature at ℃, with stirring, β-t-butyloxycarbonyl-γ, γ-dimethyl-α-methacryloyloxy-γ-butyrolactone 14.01 g (47.0 mmol), 9-methacryloyloxy-2-oxatricyclo [ 4.2.1.0 ^4,8 ] nonan-3-one 10.44 g (47.0 mmol), 1-hydroxy-3-methacryloyloxyadamantane 5.55 g (23.5 mmol), dimethyl 2,2′-azo Bisisobutyrate (Initiator: Wako Pure Chemical Industries, trade name “V-601”) 0 A monomer solution in which .75 g, PGMEA 77.35 g, and PGME 33.15 g were mixed was dropped at a constant rate over 6 hours. After completion of the dropwise addition, stirring was continued for another 2 hours. After completion of the polymerization reaction, the obtained reaction solution was filtered with a filter having a pore size of 0.1 μm, and then stirred in a 9: 1 (volume ratio; 25 ° C.) mixture of hexane and ethyl acetate in an amount 7 times that of the reaction solution. While dripping. The resulting precipitate was filtered off to obtain 27.3 g of the desired resin. When the recovered polymer was analyzed by GPC (gel permeation chromatography), the weight average molecular weight (Mw) was 8800, and the molecular weight distribution (Mw / Mn) was 1.82.

実施例１において、モノマー成分として、β−ｔ−ブチルオキシカルボニル−γ，γ−ジメチル−α−メタクリロイルオキシ−γ−ブチロラクトン１７．０１ｇ（５７．１ｍｍｏｌ）、９−メタクリロイルオキシ−２−オキサトリシクロ［４．２．１．０^4,8］ノナン−３−オン７．６０ｇ（３４．２ｍｍｏｌ）、１−ヒドロキシ−３−メタクリロイルオキシアダマンタン５．３９ｇ（２２．８ｍｍｏｌ）を用いた以外は、実施例１と同様の操作を行ったところ、所望の樹脂２６．７ｇを得た。回収したポリマーをＧＰＣ分析したところ、重量平均分子量（Ｍｗ）が８５００、分子量分布（Ｍｗ／Ｍｎ）が１．８０であった。 Example 2
Synthesis of resin with the following structure

In Example 1, as monomer components, β-t-butyloxycarbonyl-γ, γ-dimethyl-α-methacryloyloxy-γ-butyrolactone 17.01 g (57.1 mmol), 9-methacryloyloxy-2-oxatricyclo [4.2.1.0 ^4,8 ] nonane-3-one 7.60 g (34.2 mmol), 1-hydroxy-3-methacryloyloxyadamantane 5.39 g (22.8 mmol) When the same operation as in Example 1 was performed, 26.7 g of the desired resin was obtained. When the recovered polymer was analyzed by GPC, the weight average molecular weight (Mw) was 8500, and the molecular weight distribution (Mw / Mn) was 1.80.

実施例１において、モノマー成分として、β−ｔ−ブチルオキシカルボニル−γ，γ−ジメチル−α−メタクリロイルオキシ−γ−ブチロラクトン１０．６６ｇ（３５．８ｍｍｏｌ）、９−メタクリロイルオキシ−２−オキサトリシクロ［４．２．１．０^4,8］ノナン−３−オン１０．５９ｇ（４７．７ｍｍｏｌ）、１−ヒドロキシ−３−メタクリロイルオキシアダマンタン５．６３ｇ（２３．８ｍｍｏｌ）、１−（１−メタクリロイルオキシ−１−メチルエチル）アダマンタン３．１２ｇ（１１．９ｍｍｏｌ）を用いた以外は、実施例１と同様の操作を行ったところ、所望の樹脂２７．６ｇを得た。回収したポリマーをＧＰＣ分析したところ、重量平均分子量（Ｍｗ）が９１００、分子量分布（Ｍｗ／Ｍｎ）が１．８５であった。 Example 3
Synthesis of resin with the following structure

In Example 1, as monomer components, β-t-butyloxycarbonyl-γ, γ-dimethyl-α-methacryloyloxy-γ-butyrolactone 10.66 g (35.8 mmol), 9-methacryloyloxy-2-oxatricyclo [4.2.1.0 ^4,8 ] nonan-3-one 10.59 g (47.7 mmol), 1-hydroxy-3-methacryloyloxyadamantane 5.63 g (23.8 mmol), 1- (1-methacryloyl) The same operation as in Example 1 was carried out except that 3.12 g (11.9 mmol) of oxy-1-methylethyl) adamantane was used, and 27.6 g of the desired resin was obtained. When the recovered polymer was analyzed by GPC, the weight average molecular weight (Mw) was 9100, and the molecular weight distribution (Mw / Mn) was 1.85.

実施例１において、モノマー成分として、β−ｔ−ブチルオキシカルボニル−γ，γ−ジメチル−α−メタクリロイルオキシ−γ−ブチロラクトン１０．７８ｇ（３６．２ｍｍｏｌ）、９−メタクリロイルオキシ−２−オキサトリシクロ［４．２．１．０^4,8］ノナン−３−オン１０．７１ｇ（４８．２ｍｍｏｌ）、１−ヒドロキシ−３−メタクリロイルオキシアダマンタン５．６９ｇ（２４．１ｍｍｏｌ）、２−メタクリロイルオキシ−２−メチルアダマンタン２．８２ｇ（１２．１ｍｍｏｌ）を用いた以外は、実施例１と同様の操作を行ったところ、所望の樹脂２５．５ｇを得た。回収したポリマーをＧＰＣ分析したところ、重量平均分子量（Ｍｗ）が９３００、分子量分布（Ｍｗ／Ｍｎ）が１．８６であった。 Example 4
Synthesis of resin with the following structure

In Example 1, as monomer components, β-t-butyloxycarbonyl-γ, γ-dimethyl-α-methacryloyloxy-γ-butyrolactone, 10.78 g (36.2 mmol), 9-methacryloyloxy-2-oxatricyclo [4.2.1.0 ^4,8 ] nonan-3-one 10.71 g (48.2 mmol), 1-hydroxy-3-methacryloyloxyadamantane 5.69 g (24.1 mmol), 2-methacryloyloxy-2 -The same operation as in Example 1 was carried out except that 2.82 g (12.1 mmol) of methyl adamantane was used, and 25.5 g of the desired resin was obtained. When the collected polymer was analyzed by GPC, the weight average molecular weight (Mw) was 9300, and the molecular weight distribution (Mw / Mn) was 1.86.

Evaluation test About the polymer obtained in the above Example, 100 parts by weight of the polymer and 10 parts by weight of triphenylsulfonium hexafluoroantimonate were mixed with propylene glycol monomethyl ether (PGME) as a solvent to obtain a polymer concentration of 17% by weight. A photoresist resin composition was prepared. This composition was applied on a silion wafer by a spin coating method to form a photosensitive layer having a thickness of 1.0 μm. After pre-baking at a temperature of 100 ° C. for 150 seconds using a hot plate, exposure was performed at a dose of 30 mJ / cm ² through a mask using a KrF excimer laser with a wavelength of 247 nm, and then post-baking was performed at a temperature of 100 ° C. for 60 seconds. Subsequently, it developed for 60 second with 0.3M tetramethylammonium hydroxide aqueous solution, and rinsed with the pure water. As a result, a 0.20 μm line and space pattern was clearly and accurately obtained.

Claims (8)

Following formula (1)

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms. R ^b represents a group removable by an acid. R ¹ , R ² is the same or different and represents a hydrocarbon group, R ¹ and R ² may be bonded to each other to form a ring together with adjacent carbon atoms, and R ³ and R ⁴ may be the same or different. Represents a hydrogen atom or a hydrocarbon group)
An α-unsaturated acyloxy-γ-butyrolactone derivative represented by the formula: Formula (I)

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms. R ^b represents a group removable by an acid. R ¹ , R ² is the same or different and represents a hydrocarbon group, R ¹ and R ² may be bonded to each other to form a ring together with adjacent carbon atoms, and R ³ and R ⁴ may be the same or different. Represents a hydrogen atom or a hydrocarbon group)
The high molecular compound containing the at least 1 sort (s) of monomer unit represented by these.   The polymer compound according to claim 2, further comprising a monomer unit [excluding the monomer unit represented by the formula (I)] having a group that is partly eliminated by an acid and becomes alkali-soluble.   Furthermore, the high molecular compound of Claim 2 or 3 containing the monomer unit [except the monomer unit represented by Formula (I)] which can provide adhesiveness with respect to a board | substrate. At least one monomer unit represented by the formula (I), and the following formulas (IIa) to (IIh):

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms or a haloalkyl group having 1 to 6 carbon atoms. R ⁵ and R ⁶ are the same or different and have 1 to 8 carbon atoms. R ⁷ , R ⁸ and R ⁹ are the same or different and represent a hydrogen atom, a hydroxyl group or a methyl group, and R ¹⁰ and R ¹¹ are the same or different and represent a hydrogen atom, a hydroxyl group Or -COOR ¹² group, R ¹² represents a t-butyl group, 2-tetrahydrofuranyl group, 2-tetrahydropyranyl group or 2-oxepanyl group, R ¹³ represents a methyl group or an ethyl group, R ¹⁴ and R ¹⁵ is the same or different and represents a hydrogen atom, a hydroxyl group or an oxo group, and R ¹⁶ has a substituent having a tertiary carbon atom at the bonding site with the oxygen atom shown in the formula. .R ¹⁷ showing a which may be a hydrocarbon group, ^18, R ^19, R ²⁰ and R ²¹ are the same or different, .R ²² represent a hydrogen atom or a methyl group is t- butyl, 2-tetrahydrofuranyl group, 2-tetrahydropyranyl group or a 2-oxepanyl group R ²³ and R ²⁴ are the same or different and each represents a hydrogen atom, an alkyl group or a fluoroalkyl group, R ²⁵ represents a hydrogen atom or an organic group, m represents an integer of 1 to 3, and n represents 0 or 1)
The polymer compound according to claim 2, comprising at least one monomer unit selected from the group consisting of: Further, the following formulas (IIIa) to (IIIh)

(In the formula, R ^a represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms or a haloalkyl group having 1 to 6 carbon atoms. R ²⁶ and R ²⁷ are the same or different and each represents a hydrogen atom or a hydroxyl group. or a carboxyl group, R ²⁸ represents a hydroxyl group, .X ^1, X ² and X ³ showing an oxo group or a carboxyl group are the same or different, -CH ₂ - or -CO-O- shown .R ²⁹ , R ³⁰ and R ³¹ are the same or different and each represents a hydrogen atom or a methyl group, and R ³² and R ³³ are the same or different and each represents a hydrogen atom or a methyl group, R ³⁴ , R ³⁵ , R ³⁶ , R ³⁷ and R ³⁸ are the same or different and each represents a hydrogen atom or a methyl group, and R ³⁹ is a hydrogen atom or a linear or branched chain having 1 to 20 carbon atoms which may have a substituent. , .R ^40, R ⁴¹ showing a cyclic or bridged cyclic hydrocarbon group, R ⁴² and ⁴³ are the same or different, .R ⁴⁴ represent a hydrogen atom or a methyl group, a hydrogen atom, a hydroxyl group, .o showing a hydroxymethyl group or a carboxyl group, p, q and r are, respectively, 0 or 1 Show)
The polymer compound according to claim 2, comprising at least one monomer unit selected from monomer units represented by:   A resin composition for a photoresist, comprising at least the polymer compound according to claim 2 and a photoacid generator. A method for producing a semiconductor, comprising: applying a photoresist resin composition according to claim 7 onto a substrate or a substrate to form a resist coating film; and exposing and developing to form a pattern.