JP2012117073A - Hydroxystyrene derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydroxystyrene derivative that is used in a chemically-amplified positive resist composition which has superior resolution and hardly causes wavy defects in resist patterns so that variation in resist patterns is reduced.SOLUTION: There is provided a specific hydroxystyrene derivative that contains an anthracene group which may be substituted with an oxyalkylene group.

Description

  The present invention relates to a hydroxystyrene derivative used in a chemically amplified positive resist composition used for fine processing of semiconductors.

The resist composition is used for fine processing of a semiconductor using a lithography technique.
In lithography, as represented by the Rayleigh diffraction limit equation, in principle, the shorter the exposure wavelength, the higher the resolution. The exposure light source for lithography used in the manufacture of semiconductors has become a shorter wavelength year by year: g-line with a wavelength of 436 nm, i-line with a wavelength of 365 nm, KrF excimer laser with a wavelength of 248 nm, and ArF excimer laser with a wavelength of 193 nm. As an exposure light source, EUV (extreme ultraviolet) having a wavelength of 13 nm or less, electron beams, X-rays, and the like have been energetically studied.

  As a resist suitable for such a light source, a so-called chemically amplified resist composition using the chemical amplification effect of an acid catalyst has been proposed. In the chemically amplified resist composition, acid is generated from the radiation-sensitive acid generator in the irradiated portion, and the acid is used as a catalyst by subsequent heat treatment (hereinafter, sometimes referred to as PEB). The reaction changes the solubility of the polymer in the irradiated part in the alkaline developer, thereby giving a positive or negative pattern.

  In a chemically amplified positive resist composition, a polymer in which an alkali-soluble group is protected with a group that cleaves by the action of an acid is often used in combination with an acid generator. As the polymer component of the chemically amplified resist composition, a polymer in which the carboxyl group of hydroxystyrene and (meth) acrylic acid is protected with a group that cleaves by the action of an acid is used (for example, see Patent Document 1). .)

  In a pattern formed by lithography using such a chemically amplified positive resist composition, a wave-like shape defect caused by generation of a standing wave of radiation between the patterns has become a problem. ing. Also, there is a phenomenon that the resist pattern dimension increases or decreases due to a change in resist film thickness, that is, a so-called standing wave (hereinafter abbreviated as SW), and the variation in pattern dimension due to SW increases as the resist film thickness decreases. Tend. These problems have become more serious as the resist pattern becomes finer, and there has been a demand for a chemically amplified positive resist composition with less corrugated shape defects and less pattern variation due to SW.

  Therefore, styrene / acetoxystyrene / tert-butyl acrylate / 4- (4-tetrahydropyranoxyphenylsulfoxy) phenyl methacrylate copolymer, hydroxystyrene / styrene / tert-butyl acrylate copolymer, acid generator, dissolution inhibition A chemically amplified positive resist composition comprising an agent, triethanolamine, maleic acid, a surfactant, and a solvent has been proposed (see, for example, Patent Document 2). It was not enough.

JP 2002-287362 A JP 2006-330401 A

  An object of the present invention is to provide a hydroxystyrene derivative that is used in a chemically amplified positive resist composition that is excellent in resolution, is less likely to cause a waveform shape defect in a resist pattern, and can reduce pattern fluctuations caused by SW. is there.

  Therefore, as a result of intensive studies on the chemically amplified positive resist composition in order to solve the above-mentioned problems, the present inventors have developed a chemically amplified positive resist composition using a resin having a specific polymerization unit. It has been found that, when used, the pattern obtained is less susceptible to pattern fluctuations due to SW. The present invention relates to a hydroxystyrene derivative that derives the specific polymer unit.

（式（IIIａ）及び（IIIｂ）中、Ｒ³は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁴及びＲ⁵はそれぞれ独立に水素原子又は炭素数１〜４のアルキル基を表す。Ｅは２価の炭化水素基を表し、Ｇは単結合あるいはカルボニル基を表す。Ｒ⁶は直鎖又は分岐の炭素数１〜６のアルキル基を表し、ｎ₃は０〜９の整数を表す。） That is, the present invention provides a hydroxystyrene derivative represented by the formula (IIIa) or the formula (IIIb).

(In formulas (IIIa) and (IIIb), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. E represents a divalent hydrocarbon group, G represents a single bond or a carbonyl group, R ⁶ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and n ₃ represents an integer of 0 to 9. To express.)

  The chemically amplified positive resist composition using the hydroxystyrene derivative of the present invention is less susceptible to pattern fluctuation (waveform shape defect) due to SW, and has higher sensitivity and resolution when used for fine processing of semiconductors by lithography. Since it is a chemically amplified positive resist composition, the present invention is extremely useful industrially.

（式（II）中、Ｒ¹は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ²は炭素数１〜８のアルキル基を表し、環Ｘは脂肪族炭化水素基を表す。式（ＩＶ）中、Ｒ³は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁴及びＲ⁵はそれぞれ独立に水素原子又は炭素数１〜４のアルキル基を表し、Ｒ¹⁰は炭素数１〜６のアルキル基又は炭素数５〜７のシクロアルキル基を表す。Ｒ⁴あるいはＲ⁵がＲ¹⁰と一緒になってトリメチレン鎖もしくはテトラメチレン鎖を形成してもよい。）で示される重合単位から選ばれ、酸に不安定な基を持つ重合単位とを含有し、さらに
式（III）

（式（III）中、Ｒ³は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁴及びＲ⁵はそれぞれ独立に水素原子又は炭素数１〜４のアルキル基を表す。Ｅは２価の炭化水素基を表し、Ｇは単結合又はカルボニル基を表し、Ｚは単結合又はアルキレン基又はカルボニル基を表す。Ｌは下式（Ｌ１）〜（Ｌ４）から選ばれる基を表す。

（式（Ｌ１）〜（Ｌ４）中、Ｒ⁶は直鎖又は分岐の炭素数１〜６のアルキル基を表し、ｎ₁は０〜３の整数、ｎ₂は０〜７の整数、ｎ₃は０〜９の整数を表す。））で示される重合単位を含有することを特徴とする。
なお、「アルキル基」というときは直鎖および分岐のものを含む。

(In formula (II), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ² represents an alkyl group having 1 to 8 carbon atoms, and ring X represents an aliphatic hydrocarbon group. In (IV), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ¹⁰ represents a carbon number. Represents an alkyl group having 1 to 6 or a cycloalkyl group having 5 to 7 carbon atoms, and R ⁴ or R ⁵ may be combined with R ¹⁰ to form a trimethylene chain or a tetramethylene chain. A polymerized unit having an acid labile group selected from the units, and further comprising formula (III)

(In Formula (III), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. E represents 2 Represents a monovalent hydrocarbon group, G represents a single bond or a carbonyl group, Z represents a single bond, an alkylene group or a carbonyl group, and L represents a group selected from the following formulas (L1) to (L4).

(In the formulas (L1) to (L4), R ⁶ represents a linear or branched alkyl group having 1 to 6 carbon atoms, n ₁ is an integer of 0 to 3, n ₂ is an integer of 0 to 7, n ₃ Represents an integer of 0 to 9).
The term “alkyl group” includes straight-chain and branched ones.

（式（Ｉａ）中、Ｒ⁷は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁸は炭素数１〜４のアルキル基を表し、ｐは１〜３の整数を表し、ｑは０〜２の整数を表す。）で示されるものが好ましい。 Here, as the polymerized unit (I) derived from the hydroxystyrene, the formula (Ia)

(In Formula (Ia), R ⁷ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ⁸ represents an alkyl group having 1 to 4 carbon atoms, p represents an integer of 1 to 3, and q represents Represents an integer of 0 to 2).

R ⁷ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the alkyl group of R ⁷ is preferably a linear or branched alkyl group, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, n- A butyl group, a tert-butyl group, etc. are mentioned. In particular, a hydrogen atom or a methyl group is preferred industrially. R ⁸ represents an alkyl group having 1 to 4 carbon atoms, and examples of the alkyl group for R ⁸ include the same groups as those for R ⁷ . q is an integer of 0 to 2, and 0 or 1 is preferable among these, and 0 is particularly preferable industrially. The substitution position of R ⁸ may be any of the o-position, m-position and p-position when q is 1, and when q is 2, any substitution position can be combined. p is an integer of 1 to 3, preferably 1, and when p is 1, the substituent of the hydroxyl group may be o-position, m-position or p-position, but is industrially inexpensive. The p-position is preferred. Furthermore, when p is 2 or 3, arbitrary substitution positions can be combined.

The resin of the chemically amplified positive resist composition of the present invention comprises a polymerized unit represented by formula (II) having an acid labile group and a polymerized unit represented by formula (IV) having an acid labile group. It is preferable that the polymer contains a polymer unit having at least one group selected from formula (II) and having an acid labile group.
In the formula (II), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ² represents an alkyl group having 1 to 8 carbon atoms, and may be linear, branched, or cyclic. Of these, an ethyl group is preferable. X represents a cyclic aliphatic hydrocarbon group having 3 to 30 carbon atoms. Examples of the aliphatic hydrocarbon group include groups in which two hydrogen atoms on the same carbon are removed from cycloalkane, bicycloalkane, tricycloalkane and the like. Among these, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and a norbornyl group are preferable, and an adamantyl group is particularly preferable.

In formula (IV), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ¹⁰ represents carbon. An alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 5 to 7 carbon atoms is represented. R ⁴ or R ⁵ may combine with R ¹⁰ to form a trimethylene chain or a tetramethylene chain. Among these, a 1-ethoxyethyl group in which R ⁴ is a hydrogen atom, R ⁵ is a methyl group, R ¹⁰ is an ethyl group, or R ⁴ is a methyl group, R ⁵ is a hydrogen atom, and R ¹⁰ is an ethyl group is preferable.

（式（IIａ）中、Ｒ¹は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁹は炭素数１〜８のアルキル基を表す。）で示される重合単位が好ましい。 The polymer unit (II) having an acid labile group is represented by the formula (IIa)

(In formula (IIa), R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁹ represents an alkyl group having 1 to 8 carbon atoms).

The alkyl group for R ⁹ may be linear or branched. Specific examples of the compound that leads to the polymerization unit represented by the formula (IIa) include, for example, 2-methyl-2-adamantyl acrylate, 2-methyl-2-adamantyl methacrylate, 2-ethyl-2-adamantyl acrylate, 2-ethyl-2-adamantyl methacrylate, 2-n-butyl-2-adamantyl acrylate, 2-n-butyl-2-adamantyl methacrylate, 2-isopropyl-2-adamantyl acrylate, 2-isopropyl methacrylate Examples include 2-adamantyl. Among these, 2-ethyl-2-adamantyl (meth) acrylate is particularly preferable.

Of the polymerized units represented by the formula (III), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the alkyl group of R ³ is preferably a linear or branched alkyl group, a methyl group , Ethyl group, propyl group, isopropyl group, n-butyl group, tert-butyl group and the like. In particular, a hydrogen atom or a methyl group is preferred industrially. R ⁴ and R ⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a hydroxyl group. Specific examples of the alkyl group having 1 to 4 carbon atoms and the alkoxy group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-butyl group, a tert-butyl group, a methoxy group, an ethoxy group, and a tert-butoxy group. Is mentioned.

  E represents a divalent hydrocarbon group, and the number of carbon atoms is preferably 1-8. E is preferably a divalent saturated hydrocarbon group. More preferably, it is a divalent saturated hydrocarbon group containing an alkylene group or cyclohexyl, specifically, methylene group, ethylene group, propylene group, cyclohexane-1,4-methylene group, cyclohexane-1,4-ethylene. Examples include groups.

G represents a single bond or a carbonyl group, and a single bond is preferred.
Z represents a single bond, an alkylene group or a carbonyl group, and a carbonyl group is preferred. As for carbon number of an alkylene group, 1-8 are preferred.
L represents a group selected from the formulas (L1) to (L4), among which (L3) and (L4) are preferable, and (L3) is more preferable.

  The content of the polymerization unit represented by the formula (II) in the resin is preferably in the range of 0.1 to 50 mol% with respect to the resin, and the content of the polymerization unit represented by the formula (III) in the resin is The range of 0.1-30 mol% with respect to resin is preferable.

  The resin contained in the chemically amplified positive resist composition of the present invention may be composed of a single polymer or a plurality of polymers, and has a formula (II) having an acid-labile group. One or more polymer units selected from the group consisting of polymer units represented by formula (IV) having a group unstable to acid and an acid labile group, polymer units (I), and formula (III) As for the polymerized units, all of the three or more polymerized units may be contained in the resin. All of the three or more kinds of polymerized units may be contained in one polymer. For example, the polymer represented by the formula (II) having a polymerized unit (I) and an acid labile group. The unit is contained in one kind of polymer, and the polymerized units represented by the polymerized units (I) and (III) are contained in two kinds of polymerized units as in the case of being contained in another polymer. The above polymers may be contained separately. Among them, when all are contained in one kind of polymer, that is, itself is insoluble or hardly soluble in an alkaline aqueous solution, but after an acid-labile group is cleaved by the action of an acid, the aqueous alkaline solution The soluble resin is represented by polymerized unit (I), one or more polymerized units represented by formula (II) or formula (IV), having an acid labile group, and further represented by formula (III). A resin containing a polymer containing a polymerized unit is preferred.

  The resin component constituting the positive resist composition of the present invention must contain the above-described polymerized units, but is derived from other polymerized units such as styrene, acrylonitrile, methyl methacrylate, methyl acrylate and the like. Each polymerization unit may be included.

  The resin of the present invention can be obtained by polymerizing a monomer for deriving each polymerization unit by a conventional method. For example, a monomer (for example, acetoxystyrene) obtained by protecting a phenolic hydroxyl group of a monomer derived from hydroxystyrene with a acetyl group and a monomer that induces a polymerization unit (II) and a polymerization unit (III) It can be produced by copolymerizing the derived monomer with a conventional method and then appropriately hydrolyzing it to change a part or all of the acetoxy group to a hydroxyl group. As a copolymerization method, for example, a method in which a raw material monomer is dissolved in an appropriate solvent, a polymerization initiator is added thereto to initiate polymerization, and the reaction is continued under heating or heat removal can be employed. Examples of the reaction solvent include alcohols such as methanol, ethanol, 2-propanol and tert-butanol, aromatic hydrocarbons such as benzene, toluene and xylene, ethers such as tetrahydrofuran and 1,4-dioxane, and the like. Can be used. As the polymerization initiator, 2,2′-azobis (isobutyronitrile), azo compounds such as dimethyl 2,2′-azobis (2-methylpropionate), benzoyl peroxide, tert-peroxide- Peroxides such as butyl, hydrogen peroxide / ferrous salts, redox initiators such as benzoyl peroxide / dimethylaniline, metal alkylates such as butyllithium and triethylaluminum can be used.

（式（IIIａ）及び（IIIｂ）中、Ｒ³は水素原子又は炭素数１〜４のアルキル基を表し、Ｒ⁴及びＲ⁵はそれぞれ独立に水素原子又は炭素数１〜４のアルキル基を表す。Ｅは２価の炭化水素基を表し、Ｇは単結合又はカルボニル基を表す。Ｒ⁶は直鎖又は分岐の炭素数１〜６のアルキル基を表し、ｎ₃は０〜９の整数を表す。） As the monomer for deriving the polymerization unit represented by the formula (III), a hydroxystyrene derivative represented by the formula (IIIa) or the formula (IIIb) is preferable.

(In formulas (IIIa) and (IIIb), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. E represents a divalent hydrocarbon group, G represents a single bond or a carbonyl group, R ⁶ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and n ₃ represents an integer of 0 to 9. To express.)

  The polymer obtained by polymerizing the hydroxystyrene derivatives represented by the formula (IIIa) or the formula (IIIb) or copolymerizing the hydroxystyrene derivative and another polymerizable compound is a chemically amplified positive type of the present invention. Particularly preferred for resist compositions.

  Examples of the radiation sensitive acid generator used in the present invention include compounds represented by the formula (VII).

（式（ＶII）中、Ｒ²¹は炭素数１〜３０の置換されていてもよい炭化水素基を表す。ただし、該炭化水素基に含まれる炭素原子は、その一部が任意に、カルボニル基、酸素原子に置換されていてもよい。Ａ⁺は有機対イオンを表す。Ｙ¹およびＹ²はそれぞれ独立にフッ素原子または炭素数１〜６のペルフルオロアルキル基を表す。）

(In the formula (VII), R ²¹ represents an optionally substituted hydrocarbon group having 1 to 30 carbon atoms. However, a part of the carbon atoms contained in the hydrocarbon group is optionally a carbonyl group. A ⁺ represents an organic counter ion, and Y ¹ and Y ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group.)

式（ＸＩ）および式（ＸII）中、環Ｗはそれぞれ炭素数３〜３０の単環式または多環式炭化水素基を表し、Ａ⁺は有機対イオンを表す。Ｙ¹およびＹ²はそれぞれ独立にフッ素原子または炭素数１〜６のペルフルオロアルキル基を表す。式（ＸＩ）および式（ＸII）中の環Ｗは炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数１〜４のペルフルオロアルキル基、炭素数１〜６のヒドロキシアルキル基、水酸基又はシアノ基を置換基として含んでいてもよい。 Among the compounds represented by the formula (VII), as the acid generator contained in the chemically amplified positive resist composition of the present invention, the radiation sensitivity comprising the compound represented by the formula (XI) or the formula (XII) The acid generator is more preferable because it becomes a radiation-sensitive acid generator that provides a chemically amplified positive resist composition exhibiting excellent resolution and pattern shape.

In formula (XI) and formula (XII), each ring W represents a monocyclic or polycyclic hydrocarbon group having 3 to 30 carbon atoms, and A ⁺ represents an organic counter ion. Y ¹ and Y ² each independently represent a fluorine atom or a C 1-6 perfluoroalkyl group. Ring W in Formula (XI) and Formula (XII) is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl having 1 to 6 carbon atoms. A group, a hydroxyl group or a cyano group may be contained as a substituent.

  Examples of such a ring W include a cycloalkyl skeleton having 4 to 8 carbon atoms, an adamantyl skeleton, a norbornane skeleton, and the like. Any of these skeletons are substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, a hydroxyl group, or a cyano group. May be included.

  Furthermore, the compound shown by the following Formula (VIII) is mentioned as a radiation sensitive acid generator used for this invention.

式（ＶIII）中、Ｒ²³は直鎖または分岐のペルフルオロアルキル基、あるいはアリール基を表す。Ａ⁺は有機対カチオンを表す。式（ＶIII）におけるＡ⁺は式（ＶII）におけるＡ⁺と同一でも異なっていてもよい。

In the formula (VIII), R ²³ represents a linear or branched perfluoroalkyl group or an aryl group. A ⁺ represents an organic counter cation. A ⁺ may be the same or different and A ⁺ in formula (VII) in the formula (VIII).

The linear or branched perfluoroalkyl group of R ²³ represented by the formula (VIII) preferably has 1 to 8 carbon atoms. Specific examples of the anion moiety represented by the formula (VIII) include trifluoromethanesulfonate, pentafluoro Examples include ethane sulfonate, heptafluoropropane sulfonate, perfluorobutane sulfonate, and perfluorooctane sulfonate.

The aryl group for R ^{23 represented} by formula (VIII) is not particularly limited, and part or all of the hydrogen atoms may be substituted with an alkyl group, an alkoxy group, a halogen atom, or the like.
Examples of the basic ring structure excluding the substituent include a phenyl group, a naphthyl group, and an anthracenyl group. Specific examples of the anion moiety represented by the formula (III) include benzene sulfonate, p-toluene sulfonate, triisopropyl benzene sulfonate, 2-fluorobenzene sulfonate, 4-fluorobenzene sulfonate, 2,4-difluoro. Examples include benzene sulfonate, 4- (n-butyl) benzene sulfonate, 4- (n-octyl) benzene sulfonate, 4- (n-dodecyl) benzene sulfonate, and the like.

In the acid generator represented by the formula (VII) or the formula (VIII), A ⁺ represents an organic counter ion, specifically, the following formula (VIIIa), formula (VIIIb), formula (VIIIc) or And at least one cation selected from the group consisting of cations represented by formula (VIIId).

式（ＶIIIａ）中、Ｐ¹〜Ｐ³は、互いに独立に、直鎖又は分岐の炭素数１〜３０のアルキル基又は炭素数３〜３０の環式炭化水素基を表す。Ｐ¹〜Ｐ³がアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ¹〜Ｐ³が環式炭化水素基である場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。該アルキル基及び該アルコキシ基は、直鎖でも分岐していてもよい。 Here, the formula (VIIIa) is the following formula.

In formula (VIIIa), P ^{1 to} P ³ each independently represent a linear or branched alkyl group having 1 to 30 carbon atoms or a cyclic hydrocarbon group having 3 to 30 carbon atoms. When P ^{1 to} P ³ are alkyl groups, they may contain one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent, When P ^{1 to} P ³ are cyclic hydrocarbon groups, one or more of a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms may be included as a substituent. The alkyl group and the alkoxy group may be linear or branched.

Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, hexyloxy group, octyloxy group, 2-ethylhexyloxy group and the like.
Specific examples of the cyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, an adamantyl group, a bicyclohexyl group, a phenyl group, a naphthyl group, a fluorenyl group, and a biphenyl group.

式（ＶIIIｂ）中、Ｐ⁴およびＰ⁵は、互いに独立に、水素原子、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基を表し、該アルキル基及び該アルコキシ基は、式（ＶIIIａ）のアルキル基及びアルコキシ基と同じ意味を表す。 Formula (VIIIb) is the following formula.

In formula (VIIIb), P ⁴ and P ⁵ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, and the alkyl group and the alkoxy group are Represents the same meaning as the alkyl group and alkoxy group in formula (VIIIa).

式（ＶIIIｃ）中、Ｐ⁶およびＰ⁷は、互いに独立に、炭素数１〜１２のアルキル基又は炭素数３〜１２のシクロアルキル基を表し、該アルキル基は、直鎖でも分岐していてもよい。該アルキル基の具体例としては、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、ｓｅｃ−ブチル基、ｔｅｒｔ−ブチル基、ペンチル基、ヘキシル基、オクチル基、２−エチルヘキシル基などが挙げられる。該シクロアルキル基としては、シクロプロピル基、シクロブチル基、シクロペンチル基、シクロヘキシル基、シクロヘプチル基、シクロデシル基などが挙げられる。また、Ｐ⁶とＰ⁷とが結合して、アルキレン基などの炭素数３〜１２の２価の炭化水素基であってもよい。Ｐ⁸は水素原子を表し、Ｐ⁹は炭素数１〜１２のアルキル基、炭素数３〜１２のシクロアルキル基、またはフェニル基、ベンジル基などの置換されていてもよい芳香環基をあらわすか、Ｐ⁸とＰ⁹とが結合して、アルキレン基などの炭素数３〜１２の２価の炭化水素基を表す。Ｐ⁹がアルキル基の場合、該アルキル基の具体例としては、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、ｓｅｃ−ブチル基、ｔｅｒｔ−ブチル基、ペンチル基、ヘキシル基、オクチル基、２−エチルヘキシル基などが挙げられる。Ｐ⁹がシクロアルキル基の場合、該シクロアルキル基としては、シクロプロピル基、シクロブチル基、シクロペンチル基、シクロヘキシル基、シクロヘプチル基、シクロデシル基などが挙げられる。ここで、式（ＶIIIｃ）における２価の炭化水素基に含まれる炭素原子は、その一部が任意に、カルボニル基、酸素原子、硫黄原子に置換されていてもよい。 Formula (VIIIc) is the following formula.

In formula (VIIIc), P ⁶ and P ⁷ each independently represent an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, and the alkyl group may be linear or branched. Also good. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl. Group and the like. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclodecyl group. Further, by bonding P ⁶ and P ^7, it may be a divalent hydrocarbon group having 3 to 12 carbon atoms such as an alkylene group. P ⁸ represents a hydrogen atom, and P ⁹ represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an optionally substituted aromatic ring group such as a phenyl group or a benzyl group. , P ⁸ and P ⁹ are bonded to each other to represent a C 3-12 divalent hydrocarbon group such as an alkylene group. When P ⁹ is an alkyl group, specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group. Group, octyl group, 2-ethylhexyl group and the like. When P ⁹ is a cycloalkyl group, examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclodecyl group. Here, a part of carbon atoms contained in the divalent hydrocarbon group in the formula (VIIIc) may be optionally substituted with a carbonyl group, an oxygen atom, or a sulfur atom.

式（ＶIIIｄ）中、Ｐ¹⁰〜Ｐ²¹は、互いに独立に、水素原子、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基を表す。該アルキル基及び該アルコキシ基は、式（ＶIIIａ）のアルキル基及びアルコキシ基と同じ意味を表す。Ｄは、硫黄原子又は酸素原子を表す。ｍは、０又は１を表す。 Formula (VIIId) is the following formula.

Wherein (VIIId), P ¹⁰ ~P ²¹ independently represent a hydrogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 12 carbon atoms having 1 to 12 carbon atoms. The alkyl group and the alkoxy group have the same meaning as the alkyl group and alkoxy group of the formula (VIIIa). D represents a sulfur atom or an oxygen atom. m represents 0 or 1.

Specific examples of the cation A ^{+ represented by} the formula (VIIIa) include cations represented by the following formula.

Specific examples of the cation A ⁺ represented by the formula (VIIIb) include cations represented by the following formula.

Specific examples of the cation A ⁺ represented by the formula (VIIIc) include cations represented by the following formula.

Specific examples of the cation A ⁺ represented by the formula (VIIId) include cations represented by the following formula.

式（ＶIIIｅ）〜（ＶIIIｇ）中、Ｐ²⁸〜Ｐ³⁰は互いに独立に、直鎖又は分岐の炭素数１〜２０のアルキル基を表すか又はフェニル基以外の炭素数３〜３０の環式炭化水素基を表す。Ｐ²⁸〜Ｐ³⁰がアルキル基である場合には、水酸基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基の一つ以上を置換基として含んでいてもよく、Ｐ²⁸〜Ｐ³⁰が環式炭化水素基の場合には、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基の一つ以上を置換基として含んでいてもよい。式中のＰ³¹〜Ｐ³⁶は、水酸基、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基又は炭素数３〜１２の環式炭化水素基を表し、ｌ、ｋ、ｊ、ｉ、ｈおよびｇは、互いに独立に０〜５の整数を表す。 A ⁺ is preferably a cation represented by the formula (VIIIe), the formula (VIIIf) or the formula (VIIIg).

In formulas (VIIIe) to (VIIIg), P ^{28 to} P ³⁰ each independently represent a linear or branched alkyl group having 1 to 20 carbon atoms, or cyclic carbonization having 3 to 30 carbon atoms other than a phenyl group. Represents a hydrogen group. When P ^{28 to} P ³⁰ are alkyl groups, they may contain one or more of a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, or a cyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent, If P ²⁸ to P ³⁰ is a cyclic hydrocarbon group, a hydroxyl group, it may be included as one or more of the substituents for the alkyl group or alkoxy group having 1 to 12 carbon atoms having 1 to 12 carbon atoms. P ^{31 to} P ³⁶ in the formula represent a hydroxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms or a cyclic hydrocarbon group having 3 to 12 carbon atoms, and l, k, j, i, h and g each independently represent an integer of 0 to 5.

式（ＶIIIｈ）中、Ｐ²⁵〜Ｐ²⁷は、互いに独立に、水素原子、水酸基、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシ基を表し、該アルキル基及び該アルコキシ基は、直鎖でも分岐していてもよい。 Furthermore, it is more preferable that A ⁺ is a cation represented by the formula (VIIIh).

In formula (VIIIh), P ^{25 to} P ²⁷ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, and the alkyl group and the alkoxy group are They may be linear or branched.

式（ＶIIIｉ）中、Ｐ²²〜Ｐ²⁴は、互いに独立に、水素原子、炭素数１〜４のアルキル基を表し、該アルキル基は、直鎖でも分岐していてもよい。 Furthermore, it is preferable that A ⁺ is a cation represented by the formula (VIIIi).

In formula (VIIIi), P ^{22 to} P ²⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the alkyl group may be linear or branched.

  Examples of the radiation sensitive acid generator used in the present invention include halogenated alkyltriazine compounds. Specific examples of such a radiation sensitive acid generator include 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2,4,6-tris (trichloromethyl) -1. , 3,5-triazine, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-chlorophenyl) -4,6-bis (trichloromethyl) -1,3 , 5-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy-1-naphthyl) -4,6-bis ( Trichloromethyl) -1,3,5-triazine, 2- (benzo [d] [1,3] dioxolan-5-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2 -(4-methoxystyryl) -4, -Bis (trichloromethyl) -1,3,5-triazine, 2- (3,4,5-trimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- ( 3,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1,3 , 5-triazine, 2- (2-methoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-butoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-pentyloxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine and the like.

  Examples of the radiation sensitive acid generator used in the present invention include sulfonic acid ester compounds. Specific examples of such a radiation sensitive acid generator include 1-benzoyl-1-phenylmethyl p-toluenesulfonate (commonly known as benzoin tosylate), 2-benzoyl-2-hydroxy-2-phenylethyl p-toluenesulfonate. (Commonly known as α-methylol benzoin tosylate), 1,2,3-benzenetriyl trismethanesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate, 2-nitrobenzyl p-toluenesulfonate, 4-nitrobenzyl p-toluene Sulfonate, N- (ethylsulfonyloxy) succinimide, N- (isopropylsulfonyloxy) succinimide, N- (butylsulfonyloxy) succinimide, N- (hexylsulfonyloxy) succinimide, N- (trifluoromethyl) Sulfonyloxy) succinimide, N- (chloromethylsulfonyloxy) succinimide, N- (cyclohexylmethylsulfonyloxy) succinimide, N- (benzylsulfonyloxy) succinimide, N- (phenylsulfonyloxy) succinimide, N- (p- or o) -Trissulfonyloxy) succinimide, N- (2,5-xylylsulfonyloxy) succinimide, N- (4-ethylphenylsulfonyloxy) succinimide, N- (2,4,6-trimethylphenylsulfonyloxy) succinimide, N -(2,4,6-triisopropylphenylsulfonyloxy) succinimide, N- (4-methoxyphenylsulfonyloxy) succinimide, N- (4-chlorophenylsulfonyloxy) succin Synimide, N- (2,4,5-trichlorophenylsulfonyloxy) succinimide, N- (2- or 4-nitrophenylsulfonyloxy) succinimide, N- (4-methoxy-2-nitrophenylsulfonyloxy) succinimide, N -(1-naphthylsulfonyloxy) succinimide, N- (10-camphorsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) -5-norbornene-2,3- Examples thereof include dicarboximide, N- (trifluoromethylsulfonyloxy) naphthalimide, N- (10-camphorsulfonyloxy) naphthalimide and the like.

式（ＩＸ）中、Ｒ³⁰及びＲ³¹は、それぞれ独立に炭素数３〜８の分岐状又は環状のアルキル基又はアリール基を表す。Ｒ³⁰及びＲ³¹の具体例としては、ｔｅｒｔ−ブチル基、シクロヘキシル基、フェニル基、ナフチル基、アントラセニル基などが挙げられる。 Moreover, a diazomethane type compound is mentioned as a radiation sensitive acid generator used in this invention. Examples of the diazomethane-based radiation-sensitive acid generator include compounds represented by the following formula (IX).

In formula (IX), R ³⁰ and R ³¹ each independently represents a branched or cyclic alkyl group or aryl group having 3 to 8 carbon atoms. Specific examples of R ³⁰ and R ³¹ include a tert-butyl group, a cyclohexyl group, a phenyl group, a naphthyl group, and an anthracenyl group.

Specific examples of the compound represented by the formula (IX) include bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (n-butylsulfonyl) diazomethane, bis (tert-butylsulfonium) diazomethane, bis (Cyclopentylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane,
Bis (phenylsulfonyl) diazomethane, bis (4-chlorophenylsulfonyl) diazomethane, bis (p-tolylsulfonyl) diazomethane, bis (2,4-xylylsulfonyl) diazomethane, bis (4-isopropylphenylsulfonyl) diazomethane, bis (4 -Tert-butylphenylsulfonyl) diazomethane, bis (naphthylsulfonyl) diazomethane, bis (anthracenylsulfonyl) diazomethane and the like.
Of these, bis (cyclohexylsulfonyl) diazomethane is particularly preferred. These may be used alone or in combination of two or more.

  When the resin composition of the present invention is used as a chemically amplified resist composition, a basic compound, preferably a basic nitrogen-containing organic compound, particularly preferably an amine or ammonium salt is contained. By adding a basic compound as a quencher, it is possible to improve the performance degradation due to the deactivation of the acid accompanying the holding after exposure. Specific examples of the basic compound used for the quencher include those represented by the following formulas.

In the formula, R ¹¹ , R ¹² and R ¹⁷ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has about 6 to 10 carbon atoms. Of carbon atoms. Further, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. Good. At least one hydrogen atom on the amino group may be independently substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹³ or R ¹⁴ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an alkoxy group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms. Alternatively, R ¹³ and R ¹⁴ may be bonded to form an aromatic ring.
Further, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group, or alkoxy group is independently a hydroxyl group, an amino group, or an alkoxy group having about 1 to 6 carbon atoms. May be substituted. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁵ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group or a nitro group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms.
Further, at least one hydrogen atom on the alkyl group, cycloalkyl group, aryl group, or alkoxy group is independently a hydroxyl group, an amino group, or an alkoxy group having about 1 to 6 carbon atoms. May be substituted. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁶ represents an alkyl group or a cycloalkyl group. The alkyl group preferably has about 1 to 6 carbon atoms, and the cycloalkyl group preferably has about 5 to 10 carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group or cycloalkyl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

R ¹⁷ , R ¹⁸ , R ¹⁹ and R ²⁰ each independently represents an alkyl group, a cycloalkyl group or an aryl group. The alkyl group preferably has about 1 to 6 carbon atoms, the cycloalkyl group preferably has about 5 to 10 carbon atoms, and the aryl group preferably has 6 to 10 carbon atoms. Has about carbon atoms. Furthermore, at least one hydrogen atom on the alkyl group, cycloalkyl group or aryl group may be independently substituted with a hydroxyl group, an amino group, or an alkoxy group having 1 to 6 carbon atoms. . At least one of the hydrogen atoms on the amino group may be substituted with an alkyl group having 1 to 4 carbon atoms.

W represents an alkylene group, a carbonyl group, an imino group, a sulfide group or a disulfide group. The alkylene group preferably has about 2 to 6 carbon atoms.
Further, in R ^{11 to} R ²⁰ , any of those that can take both a linear structure and a branched structure may be used.

  Specific examples of such compounds include hexylamine, heptylamine, octylamine, nonylamine, decylamine, aniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, 1- or 2-naphthylamine, and ethylenediamine. Tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'- Diethyldiphenylmethane, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, N-methylaniline, piperidine, diphenylamine, triethylamine, trimethylamine, tripropylamine, tributylamine , Tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine Methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, N, N-dimethylaniline, 2,6-isopropylaniline, imidazole, pyridine, -Methylpyridine, 4-methylimidazole, bipyridine, 2,2'-dipyridylamine, di-2-pyridyl ketone, 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,3-di (4-pyridyl) propane, 1,2-bis (2-pyridyl) ethylene, 1,2-bis (4-pyridyl) ethylene, 1,2-bis (4-pyridyloxy) ethane, 4 , 4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 1,2-bis (4-pyridyl) ethylene, 2,2'-dipicolylamine, 3,3'-dipicolylamine, tetramethylammonium hydroxide Tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetra-n-hexylammonium hydroxide, tetra-n- Examples include octylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-trifluoromethylphenyltrimethylammonium hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide (common name: choline), and the like.

  Furthermore, a hindered amine compound having a piperidine skeleton as disclosed in JP-A-11-52575 can be used as a quencher.

The resin composition of the present invention preferably contains about 80 to 99.9% by weight of the resin and about 0.1 to 20% by weight of the acid generator based on the total solid content.
Further, when a basic compound that is a quencher is used as the chemically amplified resist composition, it is preferably contained in a range of about 0.01 to 1% by weight based on the total solid content of the resist composition.
The resist composition can further contain small amounts of various additives such as sensitizers, dissolution inhibitors, other resins, surfactants, stabilizers, and dyes as necessary.

  The resist composition of the present invention is usually used as a resist solution composition in a state in which each of the above components is dissolved in a solvent, and is usually used in industrial processes such as spin coating on a substrate such as a silicon wafer. Applied according to The solvent used here may be any solvent that dissolves each component, has an appropriate drying rate, and gives a uniform and smooth coating film after the solvent evaporates, and is usually used industrially in this field. Solvents can be used.

  For example, glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate, glycol ethers such as propylene glycol monomethyl ether, esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate And ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone, and cyclic esters such as γ-butyrolactone. These solvents can be used alone or in combination of two or more.

  The resist film coated and dried on the substrate is subjected to an exposure process for patterning, followed by a heat treatment for promoting a deprotecting group reaction, and then developed with an alkali developer. The alkaline developer used here may be various alkaline aqueous solutions used in this field, but generally an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline) is used. Often used.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
In Examples and Comparative Examples, “%” and “part” representing content or use amount are based on weight unless otherwise specified. The weight average molecular weight (Mw) and dispersity (Mw / Mn) are values obtained by gel permeation chromatography using polystyrene as a standard product. The structure of the compound was confirmed by NMR.

Example 1 Synthesis of vinyl ether (D2) 5.0 parts of 9-anthracenecarboxylic acid was dissolved in 35 parts of N, N′-dimethylformamide. Thereto, 3.1 parts of potassium carbonate and 0.9 part of potassium iodide were added, stirred, and heated at 50 ° C. for 1 hour. While maintaining 50 ° C., 2.4 parts of chloroethyl vinyl ether was added dropwise over 1 hour. Heated at 50 ° C. for 5.5 hours and at 100 ° C. for 3.5 hours. It cooled to about 20 degrees C or less, and 46.4 parts of ion-exchange water were added. Extracted 4 times with 23.2 parts of ethyl acetate. The ethyl acetate layers were combined and washed 5 times with 30 parts of ion exchange water. To the ethyl acetate layer, 0.8 parts of activated carbon and 4.0 parts of magnesium sulfate were added and stirred. To the yellow solid obtained by concentrating the filtrate after filtration, 18.1 parts of n-heptane was added and stirred. The filtered product was dried to obtain 5.2 parts of (D2) as a yellow solid.

¹ H-NMR (dimethyl sulfoxide-d ₆ , internal standard substance tetramethylsilane): δ (ppm) 4.04 (dd, 1H, J = 1.8 Hz, 6.6 Hz); 4.08-4.11 ( m, 2H); 4.30 (dd, 1H, J = 1.8 Hz, 14.2 Hz); 4.80-4.83 (m, 2H); 6.61 (dd, 1H, J = 6.8 Hz) 7.54-7.65 (m, 4H); 8.02 (d, 2H, J = 9.7 Hz); 8.17 (d, 2H, J = 9.7 Hz); 8 .78 (s, 1H)
MS (ESI (+) Spectrum): [M + Na] ⁺ 315.1 (C ₁₉ H ₁₆ Na 0 ₃ ⁺ = 315.10)

Example 2 Synthesis of Resin (A1) Into a flask, 22.3 g of a methyl isobutyl ketone solution of poly (p-hydroxystyrene) (weight average molecular weight is about 15200, dispersity is 1.20 (GPC method: polystyrene conversion)) ( 7.5 g) as poly (p-hydroxystyrene), 0.0012 g of p-toluenesulfonic acid monohydrate, and 30.2 g of methyl isobutyl ketone were charged and stirred. To this resin solution, 9.4 g of (D2) was added while washing with 6 g of methyl isobutyl ketone, followed by stirring at 25 ° C. for 3.5 hours. Thereafter, 18 g of ion-exchanged water was added for liquid separation. Further, the obtained organic layer was washed and separated four times with 18 g of ion-exchanged water. After the solvent was distilled off from the organic layer and concentrated, 56 g of propylene glycol monomethyl ether acetate was added, and the solvent was further distilled off to obtain 58.8 g of a propylene glycol monomethyl ether acetate solution of resin. It was 35.4% when solid content concentration of this resin solution was calculated | required by the heating mass loss method. Moreover, it was 19.7% when the ratio of what was protected by (D2) among the hydroxyl groups in poly (p-hydroxy styrene) was calculated | required with the nuclear magnetic resonance ( ^13C -NMR) spectrometer. This resin is referred to as a resin (A1) (a polymer containing a polymer unit represented by formula (III) and a polymer unit (I)).

Example 3 Synthesis of Resin (A2) 20.0 g of the resin (A3) obtained in Synthesis Example 5 was dissolved in 120 g of methyl isobutyl ketone and concentrated to a total of 80 g. Thereto, 0.003 g of p-toluenesulfonic acid monohydrate and 57 g of methyl isobutyl ketone were charged and stirred. To this resin solution, 5.9 g of (D2) was added and stirred at 25 ° C. for 3 hours. Thereafter, 36 g of ion-exchanged water was added for liquid separation.
Further, the obtained organic layer was washed and separated four times with 36 g of ion-exchanged water. After the solvent was distilled off from the organic layer and concentrated, 150 g of propylene glycol monomethyl ether acetate was added and the solvent was further distilled off to replace the solvent, thereby obtaining 64.9 g of a propylene glycol monomethyl ether acetate solution of resin. When the solid content concentration of this resin solution was determined by the heating mass loss method, it was 39.6%. Moreover, it was 7.3% when the ratio of what was protected by (D2) among the hydroxyl groups in poly (p-hydroxystyrene) was calculated | required with the nuclear magnetic resonance ( ^13C -NMR) spectrometer. . This resin is referred to as a resin (A2) (a polymer containing a polymerized unit represented by the formula (II), a polymerized unit represented by the formula (III), and a polymerized unit (I)).

Synthesis Example 1 Synthesis of 2-ethyl-2-adamantyl methacrylate / p-acetoxystyrene copolymer (20:80) In a flask, 39.7 g (0.16 mol) of 2-ethyl-2-adamantyl methacrylate and p -Acetoxystyrene 103.8g (0.64mol) and 265g of isopropanol were put, and it heated up to 75 degreeC in nitrogen atmosphere. A solution prepared by dissolving 11.05 g (0.048 mol) of dimethyl 2,2′-azobis (2-methylpropionate) in 22.11 g of isopropanol was added dropwise to the solution. The mixture was aged at 75 ° C. for about 0.3 hours and under reflux for about 12 hours, diluted with acetone, and the reaction solution was poured into a large amount of methanol to precipitate a polymer, which was filtered off. The obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-acetoxystyrene was 250 g (however, the weight of the wet cake containing methanol).

Synthesis Example 2 Synthesis of 2-ethyl-2-adamantyl methacrylate / p-hydroxystyrene copolymer (20:80) (resin (A3))
In a flask, 250 g of a copolymer of 2-ethyl-2-adamantyl methacrylate and p-acetoxystyrene obtained in Synthesis Example 4 (20:80), 10.3 g (0.084 mol) of 4-dimethylaminopyridine. And 202 g of methanol were added and aged for 20 hours under reflux. After cooling, the reaction solution was neutralized with 7.6 g (0.126 mol) of glacial acetic acid and precipitated by pouring into a large amount of water. The precipitated polymer was separated by filtration, dissolved in acetone, and then poured into a large amount of water for precipitation to be purified three times in total. The obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-hydroxystyrene was 95.9 g. The weight average molecular weight was about 8600, the degree of dispersion was 1.65 (GPC method: polystyrene conversion), and the copolymerization ratio was determined to be about 20:80 by a nuclear magnetic resonance ( ¹³ C-NMR) spectrometer. . This resin is referred to as a resin (A3) (a polymer containing a polymer unit represented by formula (II) and a polymer unit (I)).

Synthesis Example 3 Synthesis of 2-ethyl-2-adamantyl methacrylate and p-acetoxystyrene copolymer (30:70) In a flask, 59.6 g (0.24 mol) of 2-ethyl-2-adamantyl methacrylate and p -Acetoxystyrene 90.8g (0.56mol) and 279g of isopropanol were put, and it heated up to 75 degreeC in nitrogen atmosphere. A solution prepared by dissolving 11.05 g (0.048 mol) of dimethyl 2,2′-azobis (2-methylpropionate) in 22.11 g of isopropanol was added dropwise to the solution. The mixture was aged at 75 ° C. for about 0.3 hours and under reflux for about 12 hours, diluted with acetone, and the reaction solution was poured into a large amount of methanol to precipitate a polymer, which was filtered off.
The weight of the obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-acetoxystyrene was 250 g as the weight of the wet cake containing methanol.

Synthesis Example 4 Synthesis of 2-ethyl-2-adamantyl methacrylate and p-hydroxystyrene copolymer (30:70) (resin (A4)) 2-ethyl-2methacrylate obtained in Synthesis Example 6 was added to a flask. A copolymer of adamantyl and p-acetoxystyrene (30:70) (250 g), 4-dimethylaminopyridine (10.8 g (0.088 mol)) and methanol (239 g) were added, followed by aging under reflux for 20 hours. After cooling, the reaction solution was neutralized with 8.0 g (0.133 mol) of glacial acetic acid and precipitated by pouring into a large amount of water. After the precipitated polymer was dissolved in acetone, the operation of pouring into water and precipitating was repeated 3 times in total for purification. The crystal of the obtained copolymer of 2-ethyl-2-adamantyl methacrylate and p-hydroxystyrene was 102.8 g. The weight average molecular weight was about 8200, and the degree of dispersion was 1.68 (GPC method: polystyrene conversion), and the copolymerization ratio was determined to be about 30:70 by a nuclear magnetic resonance ( ¹³ C-NMR) spectrometer. This resin is referred to as a resin (A4) (a polymer containing a polymer unit represented by formula (II) and a polymer unit (I)).

Reference Examples 1-2 and Comparative Example 1
The components shown in Table 1 below were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution. In addition, the numerical value in () shows a compounding quantity (part by weight).

  In the composition shown in Table 1, components other than the resins (A1) to (A4) were as follows.

Acid generator (B1): Triphenylsulfonium 2,4,6-triisopropylbenzenesulfonate (B2): Bis (cyclohexylsulfonyl) diazomethane

Quencher (C1): 2,6-diisopropylaniline

Solvent (S1): Propylene glycol monomethyl ether acetate (PGMEA) / propylene glycol monomethyl ether (PGME) = 8/2 (weight ratio)

  Each resist solution is spin-coated on a silicon wafer by a conventional method, and then prebaked on a proximity hot plate at 90 ° C. for 60 seconds to form a resist film having a thickness of 0.24 μm. It was. Using a KrF excimer exposure apparatus (“NSR-2205EX12B” manufactured by Nikon Corporation, NA = 0.55, σ = 0.80) on the wafer on which the resist film was formed in this way, through various shapes and sizes of masks. And exposed. Next, PEB was performed on a hot plate at 110 ° C. for 60 seconds, and paddle development was further performed with a 2.38% tetramethylammonium hydroxide aqueous solution for 60 seconds. The pattern cross section after development was observed with a scanning electron microscope, the resolution and shape were examined as follows, and the results are shown in Table 2.

  Resolution: The minimum dimension (μm) of the line and space pattern that separates the 0.25 μm line and space pattern with an exposure amount of 1: 1.

  Shape: Observe the cross-sectional shape and smoothness of the pattern cross section, show the wave shape of the pattern side wall and T-top shape is shown as x, relaxed is shown as △, suppressed is shown as ○ It was.

  Each resist solution is spin-coated on a silicon wafer by a conventional method, and then pre-baked on a proximity hot plate at 90 ° C. for 60 seconds, so that the thickness is 0.20 μm to 0.30 μm. Several wafers with a resist film in between were prepared. The wafer thus formed with the resist film is exposed using a KrF excimer exposure apparatus (“NSR-2205EX12B” manufactured by Nikon Corporation, NA = 0.55, σ = 0.80), and then on a hot plate. Then, PEB was performed at 110 ° C. for 60 seconds, and paddle development was further performed with a 2.38% tetramethylammonium hydroxide aqueous solution for 60 seconds. A 0.25 μm line and space pattern with a constant exposure amount was observed, and the line width (hereinafter abbreviated as CD) of the formed resist pattern was measured.

  For the obtained CD, the difference between the largest CD and the smallest CD was determined as CD-SW (nm) and shown in Table 2. The smaller the CD-SW (nm), the better the pattern variation with respect to the film thickness change.

Claims (2)

A hydroxystyrene derivative represented by the formula (IIIa) or the formula (IIIb).

(In formulas (IIIa) and (IIIb), R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. E represents a divalent hydrocarbon group, G represents a single bond or a carbonyl group, R ⁶ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and n 3 represents an integer of 0 to 9. .) A polymer obtained by polymerizing the hydroxystyrene derivatives according to claim 1 or by copolymerizing the hydroxystyrene derivative according to claim 1 and another polymerizable compound.