JP2008046594A - Chemically amplified positive resist composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chemically amplified positive resist composition capable of forming a film excellent in cracking resistance. <P>SOLUTION: The chemically amplified positive resist composition comprises (A) a resin obtained by reacting a poly(hydroxystyrene) polymer in which part of hydrogens of phenolic hydroxyl groups have been substituted for acetal type residues and a novolac polymer with a compound containing at least two vinyl ether groups per molecule and (B) an acid generator. In the composition, the poly(hydroxystyrene) polymer may be a polymer having a structural unit represented by formula (I) and a structural unit represented by formula (Ib). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a chemically amplified positive resist composition particularly suitable for thick films.

  A chemical amplification type positive resist composition suitable for thick film is used in the formation of bumps in the manufacture of semiconductor elements, the formation of wiring patterns in the manufacture of circuit boards, the formation of thick film photoresist laminates, the thickness in the manufacture of semiconductor elements. It is used for forming a film resist pattern.

  As such a chemically amplified positive resist composition, conventionally, p-hydroxystyrene / styrene / 2-benzyl-2-propyl acrylate copolymer (resin) and 4,7-di-n-butoxynaphthyl are used. A composition comprising tetrahydrothiophenium trifluoromethanesulfonate (acid generator) and ethyl lactate (organic solvent) has been used (see, for example, Patent Document 1).

  However, the resistance to plating (plating resistance) performed in the formation of bumps in the manufacture of semiconductor elements was insufficient. Therefore, as an improved plating resistance, a copolymer (resin) of 1-ethylcyclohexyl methacrylate / 2-ethoxyethyl acrylate, a novolac resin (resin), and (5-propylsulfonyloxyimino-5H-thiophene- A chemically amplified positive resist composition for thick film composed of 2-ylidene)-(2-methylphenyl) acetonitrile (acid generator) and propylene glycol monomethyl ether acetate (organic solvent) has been proposed (for example, (See Patent Document 2), but in the formation of bumps particularly in the manufacture of semiconductor elements, a chemically amplified positive resist composition with further improved resistance to cracks (crack resistance) that may occur when a thick film is formed. Things were sought.

JP 2001-281862 A JP 2004-309775 A

  An object of the present invention is to provide a chemically amplified positive resist composition capable of forming a film having excellent crack resistance.

  As a result of intensive studies on the resin contained in the chemically amplified positive resist composition in order to solve the above-mentioned problems, the present inventors have identified a compound containing a certain amount or more of a vinyl ether group in one molecule. A chemically amplified positive resist composition comprising a resin obtained by reacting with a polymer of the above, and containing the resin, an acid generator and an organic solvent is a chemical amplification for thick film having excellent crack resistance. The present invention has been completed by finding that it is a type positive resist composition.

  That is, the present invention relates to (A) a poly (hydroxystyrene) polymer in which a part of hydrogen of a phenolic hydroxyl group is substituted with an acetal type residue and a novolak polymer, and at least two vinyl ethers in one molecule. There is provided a chemically amplified positive resist composition comprising a resin obtained by reacting with a group-containing compound and (B) an acid generator.

  The film formed from the chemically amplified positive resist composition of the present invention has excellent crack resistance and heat resistance, and in addition, the composition has excellent coatability and resolution. Suitable for thick film formation applications such as bump formation in element manufacturing, wiring pattern formation in circuit board manufacture, thick film photoresist laminate formation, thick film resist pattern formation in semiconductor element manufacturing, etc. In particular, the present invention is extremely useful industrially because it is suitable for forming bumps in the manufacture of semiconductor elements.

  The chemically amplified positive resist composition of the present invention comprises (A) one molecule of a poly (hydroxystyrene) polymer in which a part of hydrogen of a phenolic hydroxyl group is substituted with an acetal type residue and a novolac polymer. It contains a resin obtained by reacting with a compound containing at least two vinyl ether groups, and (B) an acid generator.

The poly (hydroxystyrene) polymer in which part of hydrogen of the phenolic hydroxyl group used in the present invention is substituted with an acetal type residue will be described.
As poly (hydroxystyrene), any of poly (o-hydroxystyrene), poly (m-hydroxystyrene), and poly (p-hydroxystyrene) may be used, but poly (p-hydroxystyrene) is preferably used. It is done. As such poly (hydroxystyrene), a commercially available product may be used, or a product produced according to a known method may be used. Specific examples of commercially available poly (p-hydroxystyrene) include Maruka Linker M (trade name) from Maruzen Petrochemical Co., Ltd. and VP polymer (trade name) from Nippon Soda Co., Ltd.

  Since the acetal type residue is a protecting group, it can be introduced into a polymer having a phenolic hydroxyl group by a known protecting group introduction reaction. Moreover, said polymer can also be obtained by copolymerizing an unsaturated compound which has an acetal type residue as a monomer with hydroxystyrene.

（式（Ｉ）中、Ｒ¹は、炭素数１〜４のアルキルを表し、Ｒ²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。また、Ｒ¹とＲ²が一緒になってトリメチレン鎖又はテトラメチレン鎖を形成してもよい。）
式（Ｉ）において、Ｒ¹として、メチル基が好ましく、Ｒ²として、エチル基、プロピル基、シクロヘキシル基が好ましく、Ｒ²として、シクロヘキシル基が更に好ましい。

Examples of the protecting group include 1-ethoxyethyl group, 1- (2-methylpropoxy) ethyl group, 1- (2-methoxyethoxy) ethyl group, 1- (2-acetoxyethoxy) ethyl group, 1- [2 -(1-adamantyloxy) ethoxy] ethyl group or 1- [2- (1-adamantanecarbonyloxy) ethoxy] ethyl group, tetrahydro-2-pyranyl group, tetrahydro-2-furyl group, 1-cyclohexyloxyethyl group, etc. Is mentioned. Specifically, as the poly (hydroxystyrene) polymer in which a part of hydrogen of the phenolic hydroxyl group in the present invention is substituted with an acetal type residue, the hydrogen of the phenolic hydroxyl group of the poly (hydroxystyrene) resin is acetal type. And a polymer having a structural unit represented by the formula (I) and a structural unit represented by the formula (Ib), which are substituted with the above residues.

(In Formula (I), R ¹ represents an alkyl having 1 to 4 carbon atoms, R ² represents a cycloalkyl group of the alkyl group carbon atoms or 5 to 7 1 to 6 carbon atoms. Further, R ¹ And R ² together may form a trimethylene chain or a tetramethylene chain.)
In formula (I), R ¹ is preferably a methyl group, R ² is preferably an ethyl group, a propyl group, or a cyclohexyl group, and R ² is more preferably a cyclohexyl group.

  In the present invention, a part of hydrogen of the phenolic hydroxyl group is substituted with an acetal type residue (hereinafter, “substituted with an acetal type residue” may be referred to as “protected”). As the hydroxystyrene) polymer, poly (hydroxystyrene) in which 10 to 90% of the hydroxyl groups of poly (hydroxystyrene) are protected is preferable, and poly (hydroxystyrene) in which 20 to 60% is protected is more preferable. . If the proportion of protected hydroxyl groups is less than 10% or more than 90%, it may be difficult to obtain a resin (A) having a crosslinked structure.

Poly (hydroxystyrene) in which part of the hydrogen of the phenolic hydroxyl group is protected is produced by replacing part of the hydrogen of the phenolic hydroxyl group of poly (hydroxystyrene) with an acetal type residue. be able to. Usually, it is produced by a method in which poly (hydroxystyrene) and optionally substituted 1-alkoxyalkene are reacted in the presence of an acid catalyst. By adjusting the amount of 1-alkoxyalkene that may be substituted, the proportion of protected hydroxyl groups in the resulting poly (hydroxystyrene) polymer can be adjusted. For example, when producing a poly (hydroxystyrene) polymer in which 10 to 90% of the hydroxyl groups of poly (hydroxystyrene) are protected, the total number of moles of hydroxyl groups in poly (hydroxystyrene) is: 0.1-0.9 mol of 1-alkoxyalkene which may be substituted may be used.
Examples of the acid catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, perchloric acid, and phosphoric acid; organic acids such as formic acid, acetic acid, oxalic acid, trichloroacetic acid, and p-toluenesulfonic acid. Such acid catalysts may be used alone or in combination of two or more. The amount of the acid catalyst used is usually 0.0001 to 1% by weight with respect to poly (hydroxystyrene).

The reaction between 1-alkoxyalkene which may be substituted with poly (hydroxystyrene) is usually performed by mixing 1-alkoxyalkene which may be substituted with poly (hydroxystyrene) and an acid catalyst in a solvent. To implement. The solvent is not particularly limited as long as it is an inert solvent for the reaction. The reaction temperature is usually 0 to 100 ° C., and the reaction time is usually 0.5 to 48 hours.
After completion of the reaction, for example, an organic solvent insoluble in water is added to the reaction mixture as necessary, and a basic substance such as triethylamine is added to the reaction mixture as necessary, followed by washing with water and concentration. A poly (hydroxystyrene) polymer can be removed. Moreover, you may use the reaction mixture containing a poly (hydroxy styrene) polymer for manufacture of resin (A) as it is, without taking out a poly (hydroxy styrene) polymer.

The novolak polymer used in the present invention will be described.
The novolak polymer is usually obtained by condensing a phenol compound and an aldehyde in the presence of an acid catalyst. Examples of the phenolic compound used for the production of the novolak polymer include phenol; o-, m- or p-cresol; 2,3-, 2,5-, 3,4- or 3,5-xylenol; 2 , 3,5-trimethylphenol, 2-, 3- or 4-tert-butylphenol; 2-tert-butyl-4- or 5-methylphenol; 2-, 4- or 5-methylresorcinol; 2-, 3- Or 4-methoxyphenol; 2,3-, 2,5- or 3,5-dimethoxyphenol; 2-methoxyresorcinol; 4-tert-butylcatechol; 2-, 3- or 4-ethylphenol; Or 3,5-diethylphenol; 2,3,5-triethylphenol; 2-naphthol; 1,3-, 1,5- or 1,7-dihydroxynaphthalene; and xylenol Polyhydroxy triphenylmethane compounds obtained by condensation of mud carboxy benzaldehyde, and the like. These phenolic compounds can be used alone or in combination of two or more. Among them, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 2- Preference is given to tert-butylphenol, 3-tert-butylphenol, 4-tert-butylphenol, 2-tert-butyl-4-methylphenol and 2-tert-butyl-5-methylphenol.

  Examples of the aldehyde used for producing the novolak polymer include aliphatic aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, acrolein or crotonaldehyde; cyclohexanealdehyde, cyclopentanealdehyde, furfural or Cycloaliphatic aldehydes such as furyl acrolein; benzaldehyde, o-, m- or p-methylbenzaldehyde, p-ethylbenzaldehyde, 2,4-, 2,5-, 3,4- or 3,5-dimethylbenzaldehyde or aromatic aldehydes such as o-, m- or p-hydroxybenzaldehyde; araliphatic aldehydes such as phenylacetaldehyde or cinnamic aldehydeThese aldehydes can also be used alone or in combination of two or more. Among these aldehydes, formaldehyde is preferably used because it is easily available industrially.

  Examples of acid catalysts used for the condensation of phenolic compounds with aldehydes include inorganic acids such as hydrochloric acid, sulfuric acid, perchloric acid or phosphoric acid; such as formic acid, acetic acid, oxalic acid, trichloroacetic acid or p-toluenesulfonic acid Organic acids; divalent metal salts such as zinc acetate, zinc chloride or magnesium acetate are listed. These acid catalysts can also be used alone or in combination of two or more. The amount of the acid catalyst used is usually 0.01 to 1 mol with respect to 1 mol of the aldehyde compound. The condensation reaction can be performed according to a conventional method, for example, at a temperature in the range of 60 to 120 ° C. for about 2 to 30 hours. After completion of the reaction, for example, a novolac resin can be taken out by adding a solvent insoluble in water to the reaction mixture as necessary, washing the reaction mixture with water, and concentrating.

Next, a compound containing at least two vinyl ether groups in one molecule used in the present invention will be described.
Here, the vinyl ether group is a group represented by the formula (IIx).

式（IIｙ）中、Ｘは脂肪族環状構造を含んでもよい炭素数２〜１２の２価の炭化水素基を示す。 The compound may be any compound having a plurality of vinyl ether groups in one molecule, and among them, the compound represented by the formula (IIy) is preferable.

In the formula (IIy), X represents a divalent hydrocarbon group having 2 to 12 carbon atoms which may contain an aliphatic cyclic structure.

(IIｂ) Of the compounds represented by the formula (IIy), the compound represented by the formula (IIa) and the compound represented by the formula (IIb) are particularly preferable.

(IIb)

  The resin (A) used in the present invention comprises a poly (hydroxystyrene) polymer in which a part of hydrogen of the phenolic hydroxyl group is substituted with an acetal type residue and a novolac polymer in at least 2 molecules. It is obtained by reacting with a compound containing individual vinyl ether groups.

The reaction can be carried out as follows.
First, in the presence of an acid catalyst, a part of hydrogen of the phenolic hydroxyl group of the poly (hydroxystyrene) polymer is replaced with an acetal type residue, and the novolak polymer and one molecule are added to the reaction solution without removing the acid catalyst. The reaction can be carried out by further mixing a compound containing at least two vinyl ether groups. Examples of the acid catalyst include those similar to the acid catalyst used in the method for producing a poly (hydroxystyrene) polymer. Since a compound containing at least two vinyl ether groups in one molecule is used, a so-called crosslinked structure can be formed. After this, it is desirable to remove the acid component. For this, a known method, that is, neutralization with a basic substance, water washing, ion exchange resin treatment, or the like can be used. In addition, a solvent is usually used for the reaction, and the solvent is not particularly limited as long as it is an inert solvent for the reaction. For example, methyl isobutyl ketone is used, and the amount used is not particularly limited.

The amount of the poly (hydroxystyrene) polymer in which a part of hydrogen of the phenolic hydroxyl group is substituted with an acetal type residue is at least 2 per molecule, poly (hydroxystyrene) polymer, novolak polymer. The amount is usually 20 to 80% by weight, preferably 30 to 70% by weight, based on the total amount of compounds containing individual vinyl ether groups.
In addition, if the amount of the compound containing at least two vinyl ether groups in one molecule is too large, the molecular weight of the resulting resin (A) becomes too large and the solubility of the resulting resin in the solvent decreases. If the amount used is too small, the formation of a crosslinked structure tends to be insufficient. Therefore, the amount used is preferably 2 to 20% by weight based on the total amount.

  After completion of the reaction, for example, after adding a basic substance such as triethylamine to the reaction mixture, the resin (A) can be taken out by washing with water. The taken out resin (A) may be further purified with an ion exchange resin or the like, if necessary.

  The resin (A) thus obtained has a crosslinked structure, and its weight average molecular weight is usually 30,000 to 300,000, preferably 50,000 to 200,000.

  Examples of the acid generator (B) that constitutes the resist composition of the present invention include compounds that generate an acid upon irradiation with light or radiation, and the light itself or the resist composition containing the substance contains light or By the action of radiation such as an electron beam, the substance decomposes to generate an acid. The acid generated from the acid generator acts on the resin and cleaves the acid labile group present in the resin.

（IIIａ）

（IIIｂ）
（式（IIIａ）および式（IIIｂ）中、Ｒ³は、酸素原子もしくは窒素原子を含む置換基を有してもよく、又はハロゲン原子で置換されていてもよい炭化水素基を表す。）が好ましい。Ｒ³における炭化水素基としては、炭素数１〜１２のアルキル基、および炭素数６〜１８のアリール基等が挙げられる。また、酸素原子もしくは窒素原子を含む置換基としては、エステル基、ヒドロキシル基、アルコキシル基、オキソ基、ニトロ基等が挙げられる。ハロゲン原子としては、フッ素、塩素、臭素等が挙げられる。式（IIIａ）で示される化合物および式（IIIｂ）で示される化合物として、具体的には、式（IIIａ）および式（IIIｂ）中のＲ³がｎ−プロピル基、ｎ−ブチル基、ｎ−オクチル基、トルイル基、２，４，６−トリメチルフェニル基、２，４，６−トリイソプロピルフェニル基、４−ドデシルフェニル基、４−メトキシフェニル基、２−ナフチル基、ベンジル基および下式（ＩＶ）で示される基である化合物が挙げられる。

Examples of the acid generator include at least one selected from the group consisting of onium salts, halogen-containing compounds, diazoketone compounds, sulfone compounds, and sulfonic acid compounds. In particular, when the exposure wavelength is in the vicinity of 436 nm (g line) to 365 nm (i line), the sulfonic acid oxime compound represented by the following formula (IIIa) having large absorption in the vicinity of 436 nm (g line) and 365 nm (i line) And a sulfonic acid oxime compound represented by the following formula (IIIb):

(IIIa)

(IIIb)
(In Formula (IIIa) and Formula (IIIb), R ³ represents a hydrocarbon group which may have a substituent containing an oxygen atom or a nitrogen atom, or may be substituted with a halogen atom). preferable. Examples of the hydrocarbon group for R ³ include an alkyl group having 1 to 12 carbon atoms and an aryl group having 6 to 18 carbon atoms. In addition, examples of the substituent containing an oxygen atom or a nitrogen atom include an ester group, a hydroxyl group, an alkoxyl group, an oxo group, and a nitro group. Examples of the halogen atom include fluorine, chlorine, bromine and the like. As the compound represented by the formula (IIIa) and the compound represented by the formula (IIIb), specifically, R ³ in the formula (IIIa) and the formula (IIIb) is an n-propyl group, an n-butyl group, an n- Octyl group, toluyl group, 2,4,6-trimethylphenyl group, 2,4,6-triisopropylphenyl group, 4-dodecylphenyl group, 4-methoxyphenyl group, 2-naphthyl group, benzyl group and the following formula ( And a compound represented by IV).

  In the present invention, among the compounds represented by formula (IIIa) or formula (IIIb), the compound represented by formula (IIIb) is preferred.

（式（Ｖａ）中、Ｐ¹〜Ｐ³は、互いに独立に、水酸基、炭素数１〜６のアルキル基又は炭素数１〜６のアルコキシ基を表す。ａ、ｂ、ｃは、互いに独立に０〜３の整数である。ａが２以上のとき、複数のＰ¹は、互いに同一でも異なってもよい。ｂが２以上のとき、複数のＰ²は、互いに同一でも異なってもよい。ｃが２以上のとき、複数のＰ³は、互いに同一でも異なってもよい。Ｚ^-は、有機対イオンを表す。） Examples of the acid generator in the present invention include a compound represented by the following formula (Va), a compound represented by (Vb), and a compound represented by (Vc).

(In Formula (Va), P ^{1 to} P ³ each independently represent a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. A, b, and c are independently of each other. It is an integer of 0 to 3. When a is 2 or more, the plurality of P ¹ may be the same or different from each other, and when b is 2 or more, the plurality of P ² may be the same or different from each other. When c is 2 or more, the plurality of P ³ may be the same or different from each other. Z ⁻ represents an organic counter ion.)

（式（Ｖｂ）中、Ｐ⁴、Ｐ⁵は、互いに独立に水酸基、炭素数１〜６のアルキル基又は炭素数１〜６のアルコキシ基を表す。ｄ、ｅは、互いに独立に０又は１である。Ｚ^-は、有機対イオンを表す。）

(In Formula (Vb), P ⁴ and P ⁵ each independently represent a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. D and e are each independently 0 or 1) Z ⁻ represents an organic counter ion.)

（式（Ｖｃ）中、Ｐ⁶、Ｐ⁷は、互いに独立に、炭素数１〜６のアルキル基、炭素数３〜１０のシクロアルキル基を表すか、又はＰ⁶とＰ⁷とが結合して炭素数３〜７の二価の脂肪族炭化水素基を表し、隣接するＳ⁺とともに環を形成する。該脂肪族炭化水素基の少なくとも１個の−ＣＨ₂−がカルボニル基、酸素原子もしくは硫黄原子に置換されていてもよい。Ｐ⁸が水素原子を表し、Ｐ⁹が炭素数１〜６のアルキル基、炭素数３〜１０のシクロアルキル基もしくは置換されていてもよい芳香環基を表すか、又はＰ⁸とＰ⁹とが結合して二価の脂肪族炭化水素基を表し、隣接する−ＣＨＣＯ−とともに環を形成する。Ｚ^-は、有機対イオンを表す。）

(In Formula (Vc), P ⁶ and P ⁷ each independently represent a C 1-6 alkyl group or a C 3-10 cycloalkyl group, or P ⁶ and P ⁷ are bonded to each other. Represents a divalent aliphatic hydrocarbon group having 3 to 7 carbon atoms, and forms a ring with adjacent S ⁺ , wherein at least one —CH ₂ — of the aliphatic hydrocarbon group is a carbonyl group, an oxygen atom or P ⁸ represents a hydrogen atom, and P ⁹ represents an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an optionally substituted aromatic ring group. Or P ⁸ and P ⁹ are bonded to each other to form a divalent aliphatic hydrocarbon group and form a ring together with the adjacent —CHCO—, and Z ⁻ represents an organic counter ion.)

When P ¹ , P ² and P ³ in the formula (Va) are an alkyl group or an alkoxy group, they may be linear or branched when having 3 or more carbon atoms.
When P ⁴ and P ⁵ in Formula (Vb) are an alkyl group or an alkoxy group, they may be linear or branched when they have 3 or more carbon atoms.
Examples of specific alkyl groups for P ¹ , P ² , P ³ , P ⁴ and P ⁵ include methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, pentyl group, hexyl group Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

In the formula (Vc), when P ⁶ and P ⁷ are bonded to each other to represent a C 3-7 divalent aliphatic hydrocarbon group, at least one —CH of the aliphatic hydrocarbon group _2- may be substituted with a carbonyl group, an oxygen atom or a sulfur atom.
When P ⁶ , P ⁷ and P ⁹ are alkyl groups, specific examples include methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, pentyl group, hexyl group and the like. In the case of a cycloalkyl group, specific examples include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and the like.

  Specific examples of the cation in the formulas (Va), (Vb), and (Vc) include the following.

（式（ＶＩ）中、Ｑ¹、Ｑ²、Ｑ³、Ｑ⁴及びＱ⁵は、互いに独立に、水素原子、ハロゲン原子、アルデヒド基、炭素数１〜１６個の分岐していてもよいアルキル基、炭素数１〜１６個の分岐していてもよいアルコキシ基、炭素数１〜８個のハロゲン化アルキル基、炭素数６〜１２個のアリール基、炭素数７〜１２のアラルキル基、シアノ基、炭素数１〜４個のアルキルチオ基、炭素数１〜４個のアルキルスルホニル基、ヒドロキシ基、ニトロ基又は下式（ＶII）で示される基を表す。

（式（ＶII）中、Ｘは、酸素原子又は硫黄原子を含んでも良い直鎖アルキレン基を表し、Ｃｙ¹は、炭素数３〜２０個の脂環式炭化水素基を表す。）） Specific examples of the organic counter ion Z ⁻ of the acid generator in the present invention include an anion represented by the following formula (VI).

(In formula (VI), Q ¹ , Q ² , Q ³ , Q ⁴ and Q ⁵ are each independently a hydrogen atom, a halogen atom, an aldehyde group, or an alkyl group having 1 to 16 carbon atoms which may be branched. Group, an optionally branched alkoxy group having 1 to 16 carbon atoms, a halogenated alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, cyano Group, an alkylthio group having 1 to 4 carbon atoms, an alkylsulfonyl group having 1 to 4 carbon atoms, a hydroxy group, a nitro group, or a group represented by the following formula (VII).

(In formula (VII), X represents a linear alkylene group that may contain an oxygen atom or a sulfur atom, and Cy ¹ represents an alicyclic hydrocarbon group having 3 to 20 carbon atoms.)

Examples of the optionally branched alkyl group having 1 to 16 carbon atoms in the formula (VI) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a pentyl group, and a hexyl group. Octyl group, decyl group, dodecyl group, hexadecyl group and the like.
Examples of the alkoxy group having 1 to 16 carbon atoms which may be branched include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, tert-butoxy group, pentyloxy group, hexyloxy group, isopentyl Examples thereof include an oxy group, a decyloxy group, a dodecyloxy group, and a hexadecyloxy group.

Examples of the halogenated alkyl group having 1 to 8 carbon atoms include trifluoromethyl group, perfluoroethyl, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, and the like.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, a methoxyphenyl group, and a naphthyl group.
Examples of the aralkyl group having 7 to 12 carbon atoms include a benzyl group, a chlorobenzyl group, and a methoxybenzyl group.
Examples of the alkylthio group having 1 to 4 carbon atoms include methylthio group, ethylthio group, propylthio group, isopropylthio group, and butylthio group.
Examples of the alkylsulfonyl group having 1 to 4 carbon atoms include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, an isopropylsulfonyl group, and a butylsulfonyl group.

In addition, when two or more of Q ¹ , Q ² , Q ³ , Q ⁴ and Q ^{5 in} the formula (VI) are groups represented by the formula (VI), X and Cy ^{1 of the} group are Each can be selected independently.

上記式において、（ａ−１）〜（ａ−７）の直鎖アルキレン基が好ましい。 Examples of X include the following.

In the above formula, linear alkylene groups (a-1) to (a-7) are preferred.

上記式において、シクロヘキシル基（ｂ−４）、２−ノルボルニル基（ｂ−２１）、２−アダマンチル基（ｂ−２３）、１−アダマンチル基（ｂ−２４）が好ましい。 Examples of Cy ¹ include the following.

In the above formula, a cyclohexyl group (b-4), a 2-norbornyl group (b-21), a 2-adamantyl group (b-23), and a 1-adamantyl group (b-24) are preferable.

Specific examples of the anion represented by Z ⁻ in formula (Va), formula (Vb), and formula (Vc) include the following.

（式中、Ｑ⁶は、炭素数１〜２０の分岐していてもよいパーフルオロアルキル基又は炭素数１０〜２０の置換されていてもよいナフチル基又はアントリル基を表す。） An example of the organic counter ion Z ⁻ in the acid generator is an anion represented by the following formula (VIIIa).

(In formula, Q < ⁶ > represents the C1-C20 perfluoroalkyl group which may be branched, or C10-20 optionally substituted naphthyl group or anthryl group.)

Examples of the anion represented by the formula (VIIIa) include the following.

（式中、Ｑ⁷、Ｑ⁸は、互いに独立に、炭素数１〜２０の分岐していてもよいパーフルオロアルキル基又は炭素数６〜２０の置換されていてもよい芳香環基を表す。） An example of the organic counter ion Z ⁻ in the acid generator is an anion represented by the formula (VIIIb).

(In formula, Q < ⁷ >, Q < ⁸ > represents the C1-C20 perfluoroalkyl group which may be branched, or the C6-C20 optionally substituted aromatic ring group mutually independently. )

Examples of the anion represented by the formula (VIIIb) include the following.

  As such an acid generator, a commercially available one may be used, or one produced according to a known method may be used.

  The resist composition of the present invention may contain other resins in addition to the resin (A) and the acid generator (B). Other resins include resins that are soluble in alkaline aqueous solutions or resins that have acid labile groups and are themselves insoluble or poorly soluble in alkaline aqueous solutions, but become soluble in alkaline aqueous solutions by the action of acids. Is preferred.

  Examples of the resin soluble in an alkaline aqueous solution include the novolak polymer, the poly (hydroxystyrene) polymer in which part of hydrogen of the phenolic hydroxyl group is substituted with an acetal type residue, and a resin comprising poly (hydroxystyrene) A resin composed of the novolak polymer and the poly (hydroxystyrene) polymer is preferable.

An acid-labile group, which itself is insoluble or hardly soluble in an aqueous alkali solution, but is an acid-labile group of a resin that becomes soluble in an aqueous alkaline solution by the action of an acid, such as an α of an ether bond. Examples thereof include a group having an alkyl ester whose position is a quaternary carbon atom, a group having a carboxylic acid ester such as an alicyclic ester, and a group having a lactone ring in which the α position of the ether bond is a quaternary carbon atom.
Here, the quaternary carbon atom means a carbon atom bonded to a substituent other than a hydrogen atom and not bonded to hydrogen, and an acid labile group is a carbon at the α-position of an ether bond. It is preferred that the atom is a quaternary carbon atom bonded to three carbon atoms.

When a group having a carboxylic acid ester which is one of acid labile groups is exemplified as an R ester group of —COOR, (—COO—C (CH ₃ ) ₃ is referred to as a tert-butyl ester group). An alkyl ester group in which the α-position of the ether bond represented by tert-butyl ester is a quaternary carbon atom; a methoxymethyl ester group, an ethoxymethyl ester group, a 1-ethoxyethyl ester group, a 1-isobutoxyethyl ester group, 1-isopropoxyethyl ester group, 1-ethoxypropyl ester group, 1- (2-methoxyethoxy) ethyl ester group, 1- (2-acetoxyethoxy) ethyl ester group, 1- [2- (1-adamantyloxy) Ethoxy] ethyl ester group, 1- [2- (1-adamantanecarbonyloxy) ethoxy] Acetal type ester groups such as ethyl ester group, tetrahydro-2-furyl ester group and tetrahydro-2-pyranyl ester group; isobornyl ester group and 1-alkylcycloalkyl ester group, 2-alkyl-2-adamantyl ester group, Examples include an alicyclic ester group in which the α-position of the ether bond such as 1- (1-adamantyl) -1-alkylalkyl ester group is a quaternary carbon atom.

  Among these, in particular, structural units derived from styrene monomers such as p- or m-hydroxystyrene, structural units derived from 3-hydroxy-1-adamantyl (meth) acrylate, (meth) acrylic acid 3,5 A resin comprising a structural unit derived from -dihydroxy-1-adamantyl, a structure derived from a monomer represented by formula (a), and a structural unit derived from a monomer represented by formula (b) is preferred.

（式（ａ）および式（ｂ）中、Ｒ²¹及びＲ²²は、互いに独立に、水素原子又はメチル基を表し、Ｒ²³及びＲ²⁴は、互いに独立にメチル基又はトリフルオロメチル基又はハロゲン原子を表し、ｐ及びｑは、０〜３の整数を表す。ｐが２または３のときには、Ｒ³は互いに異なる基であってもよく、ｑが２または３のときには、Ｒ²⁴は互いに異なる基であってもよい。）

(In the formulas (a) and (b), R ²¹ and R ²² each independently represent a hydrogen atom or a methyl group, and R ²³ and R ²⁴ each independently represent a methyl group, a trifluoromethyl group or a halogen atom. Represents an atom, and p and q represent an integer of 0 to 3. When p is 2 or 3, R ³ may be different from each other, and when q is 2 or 3, R ²⁴ is different from each other. It may be a group.)

  Monomers such as 3-hydroxy-1-adamantyl (meth) acrylate and 3,5-dihydroxy-1-adamantyl (meth) acrylate are commercially available. For example, the corresponding hydroxyadamantane is converted to (meth) acrylic acid or It can also be produced by reacting with the halide.

  In addition, a monomer such as (meth) acryloyloxy-γ-butyrolactone is obtained by reacting α- or β-bromo-γ-butyrolactone whose lactone ring may be substituted with an alkyl group with acrylic acid or methacrylic acid, or lactone. It can be produced by reacting an α- or β-hydroxy-γ-butyrolactone whose ring may be substituted with an alkyl group with an acrylic acid halide or a methacrylic acid halide.

  Specific examples of the monomer that gives the structural unit represented by formula (a) or formula (b) include (meth) acrylic acid esters of alicyclic lactones having a hydroxyl group such as the following, and mixtures thereof. It is done. These esters can be produced, for example, by reacting an alicyclic lactone having a corresponding hydroxyl group with (meth) acrylic acids (for example, JP-A No. 2000-26446).

  Here, as (meth) acryloyloxy-γ-butyrolactone, for example, α-acryloyloxy-γ-butyrolactone, α-methacryloyloxy-γ-butyrolactone, α-acryloyloxy-β, β-dimethyl-γ-butyrolactone, α- Methacryloyloxy-β, β-dimethyl-γ-butyrolactone, α-acryloyloxy-α-methyl-γ-butyrolactone, α-methacryloyloxy-α-methyl-γ-butyrolactone, β-acryloyloxy-γ-butyrolactone, β- Examples include methacryloyloxy-γ-butyrolactone, β-methacryloyloxy-α-methyl-γ-butyrolactone, and the like.

  Further, in the chemically amplified positive resist composition of the present invention, by adding an organic basic compound as a quencher, it is possible to improve performance deterioration due to acid deactivation accompanying holding after exposure. As the organic basic compound, a nitrogen-containing basic organic compound is particularly preferably blended as a quencher. Specific examples of such nitrogen-containing basic organic compounds include amines 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 , R ¹⁴ and R ¹⁵ 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.
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- (trifluoromethyl) phenyltrimethylammonium hydroxide, and choline.

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

  Specific examples include tetramethylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, and 3-trifluoromethyl-phenyltrimethylammonium hydroxide. .

The resist composition of the present invention has a resin content of 89 to 99.9% by weight, an acid generator of 0.1 to 10% by weight, and a quencher of 0.001 to 1% by weight based on the total solid content of the resist composition. It is preferable to contain in the range of%. The total solid content means the total amount excluding the solvent.
The composition of the present invention can also 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 made into a resist solution composition in a state where each of the above components is dissolved in a solvent, and is applied on a substrate such as a silicon wafer according to a conventional method such as spin coating. 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 a solvent generally used in this field is used. Yes.
For example, glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate; acetone, methyl isobutyl ketone, 2-heptanone And ketones such as cyclohexanone; 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.
While the embodiments of the present invention have been described above, the embodiments of the present invention disclosed above are merely examples, and the scope of the present invention is not limited to these embodiments. The scope of the present invention is defined by the terms of the claims, and further includes meanings equivalent to the description of the claims and all modifications within the scope.

EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited at all by these Examples.
In the examples, “%” and “part” representing the content or amount used are based on weight unless otherwise specified. The weight average molecular weight is a value obtained by gel permeation chromatography (HLC-8120GPC manufactured by Tosoh, column: G4000HXL and G2000HXL manufactured by Tosoh) using polystyrene as a standard product.

Resin Synthesis Example 1: Synthesis of Resin R1 (Poly (p-hydroxystyrene) Polymer in which Part of Hydrogen of Phenolic Hydroxyl Group is Replaced with Acetal Type Residue) 500 g of Maruzen Petroleum as Poly (p-hydroxystyrene) Chemical Marcalinker MS2P (trade name) was dissolved in 2000 g of methyl isobutyl ketone and concentrated until the total amount was 1667 g. To a four-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, 860 g of the obtained resin solution and methyl isobutyl ketone and 0.08 g of p-toluenesulfonic acid were added, and then 165 g of cyclohexyl vinyl ether was added at room temperature. It was added dropwise over 5 minutes. After stirring at room temperature for 3 hours, 0.01 g of triethylamine was added, and the mixture was washed with 900 g of ion-exchanged water five times. After concentrating the obtained resin solution to 1400 g, 4300 g of propylene glycol monomethyl ether acetate was added, and concentration was again performed until the total amount became 1080 g. The weight average molecular weight of the obtained resin was 5200.

Resin Synthesis Example 2: Synthesis of Resin R2 (Novolac Polymer) In a four-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, 1200 g of m-cresol, 56 g of oxalic acid dihydrate, 378 g of 90% acetic acid, 1120 g of methyl isobutyl ketone was charged, the temperature was raised to 80 ° C., and 787 g of 37% formalin was added dropwise over 1 hour while controlling the temperature to 87 ° C. at the end of dropping. After keeping the temperature at 87 ° C. for 12 hours, 1220 g of methyl isobutyl ketone was added, followed by separation and washing with ion-exchanged water 6 times. 500 g of methyl isobutyl ketone was added to the obtained resin solution, and the mixture was concentrated under reduced pressure until the total amount became 3364 g. 6152 g of methyl isobutyl ketone and 6774 g of n-heptane were added to the obtained resin liquid, the temperature was raised to 60 ° C. and stirred for 1 hour, followed by liquid separation, and the lower layer resin liquid was diluted with 3800 g of propylene glycol monomethyl ether acetate to 1800 g. Concentration was performed until The weight average molecular weight of the obtained resin was 7750.

Resin Synthesis Example 3: Synthesis of Resin R3 (Novolac Polymer) In a four-necked flask equipped with a stirrer, reflux condenser, and thermometer, 413.5 g of 2,5-xylenol, 103.4 g of salicylaldehyde, p-toluene 20.1 g of sulfonic acid and 826.9 g of methanol were charged, and the temperature was raised to a reflux state and kept for 4 hours. After cooling, 1320 g of methyl isobutyl ketone was charged and 1075 g was distilled off at normal pressure. Thereto was added 762.7 g of m-cresol and 29.0 of 2-tert-butyl-5-methylphenol, and the temperature was raised to 65 ° C. Added dropwise over 5 hours. After keeping the temperature at 87 ° C. for 10 hours, 1115 g of methyl isobutyl ketone was added, followed by separation and washing with ion-exchanged water three times. 500 g of methyl isobutyl ketone was added to the resulting resin solution and the solution was concentrated under reduced pressure until the total amount reached 3435 g. Methyl isobutyl ketone (3796 g) and n-heptane (4990 g) were added to the obtained resin liquid, and the mixture was heated to 60 ° C. and stirred for 1 hour. Concentration was performed until The weight average molecular weight of the obtained resin was 7000.

Resin Synthesis Example 4: Synthesis of Resin R4 (resin in which only a novolak polymer in which a part of the hydrogen of the phenolic hydroxyl group was substituted with an acetal type residue was reacted) was equipped with a stirrer, a reflux condenser, and a thermometer. Into a four-necked flask was charged 120 g of resin R2, 320 g of methyl isobutyl ketone, and 0.007 g of p-toluenesulfonic acid, and then 15.3 g of cyclohexyl vinyl ether was added dropwise over 5 minutes with stirring. After stirring at room temperature for 1 hour, 6.5 g of 1,4-cyclohexanedimethanol divinyl ether was added dropwise over 5 minutes. After stirring at room temperature for 2 hours, 0.02 g of triethylamine and 152 g of methyl isobutyl ketone were added, and the mixture was further washed five times with 152 g of ion-exchanged water. After concentrating the obtained resin solution to 120 g, 370 g of propylene glycol monomethyl ether acetate was added, and concentration was again performed until the total amount became 150 g. The weight average molecular weight of the obtained resin was 46900.

Resin Synthesis Example 5: Synthesis of Resin R5 (Resin (A)) 150 g of Maruka Linker S2P (trade name) made by Maruzen Petrochemical Co., Ltd., which is poly (p-hydroxystyrene), is dissolved in 600 g of methyl isobutyl ketone, so that the total amount becomes 500 g. Concentrated to To a four-necked flask equipped with a stirrer, reflux condenser, and thermometer, the obtained resin solution and 330 g of methyl isobutyl ketone and 0.02 g of p-toluenesulfonic acid were added, and then 44.6 g of cyclohexyl vinyl ether was added at room temperature. It was added dropwise over 5 minutes. After stirring at room temperature for 1 hour, 409 g of resin R2 and 1670 g of methyl isobutyl ketone were added and stirred, and then 42.9 g of 1,4-cyclohexanedimethanol divinyl ether, which is a compound containing two vinyl ether groups, was added for 5 minutes. In short, it was dripped. After stirring at room temperature for 5 hours, 0.06 g of triethylamine was added, and the mixture was further washed with 1000 g of ion-exchanged water five times. The obtained resin solution was concentrated to 830 g, 1650 g of propylene glycol monomethyl ether acetate was added, and the mixture was concentrated again until the total amount was 674 g. The weight average molecular weight of the obtained resin was 55100.

Resin Synthesis Examples 6 to 8: Synthesis of Resins R6 to R8 (Resin (A)) The same operation as in Resin Synthesis Example 5 was performed to synthesize resins having different molecular weights by changing the amount of 1,4-cyclohexanedimethanol divinyl ether. did. The molecular weight of the synthesized resin is shown in Table 1.

[Table 1]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Resin Amount of 1,4-cyclohexanedimethanol divinyl ether Mw
R6 52.7g 100531
R7 53.3g 120003
R8 71.0g 143309
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  Next, examples of preparing and evaluating resist compositions using the following acid generators and quenchers in addition to the resins and polymers will be given.

<Acid generator>
S: (2- (4-Methylphenyl) sulfonyloxyimino-2H-thiophen-3-ylidene)-(2-methylphenyl) acetonitrile <Quencher>
Q: Dicyclohexylmethylamine <solvent>
22 parts of propylene glycol monomethyl ether acetate

Examples 1-8 and Comparative Examples 1-4
The following components were mixed and dissolved, and further filtered through a fluororesin filter having a pore size of 5 μm to prepare a resist solution.

Resin or polymer (type and amount are listed in Table 2)
Acid generator (amount is listed in Table 2)
Quencher (quantity listed in Table 2)

The above resist solution was spin-coated on a silicon wafer so that the film thickness after drying was 20 μm. After applying the resist solution, it was pre-baked on a hot plate at 130 ° C. for 5 minutes. Using each i-line stepper ("NSR 1755i7A" manufactured by Nikon Corporation, NA = 0.5) on each wafer on which the resist film is formed, the exposure amount is changed stepwise to form a line and space pattern. Exposed.
After the exposure, post-exposure baking was performed on a hot plate at 130 ° C. for 1 minute, and paddle development for 60 seconds was further performed 4 times with a 2.38 wt% tetramethylammonium hydroxide aqueous solution.
In the heat resistance step, after development, baking was performed on a hot plate at a temperature of 120 ° C. for 1 minute.
The dark field patterns after development and before and after post-baking were observed with a scanning electron microscope. The results are shown in Table 3. The dark field pattern here is obtained by exposure and development through a reticle in which a glass layer (translucent layer) is formed in a line form on the outside with a chromium layer (light-shielding portion) as a base, and thus exposure development. The rest is a pattern in which the resist layer around the line and space pattern is left.

・ Applicability:
The state of the film after application was observed, and those with unevenness were indicated with ×, and those with no problem were indicated with ○.
・ Resolution:
Those in which the 20 μm line and space pattern was not resolved were indicated by ×, and those that were resolved were indicated by ◯.
・ Effective sensitivity:
The 20 μm line and space pattern was displayed at an exposure amount of 1: 1.
・ Crack resistance:
The case where cracks occurred in the film after coating was indicated by X, the case where cracks occurred in the film after development was indicated by Δ, and the case where cracks did not occur after development was indicated by ○.
·Heat-resistant:
Before and after the heat-resistant process, those having a large change in shape were indicated by ×, those having a slight change in shape were indicated by Δ, and those having no change were indicated by ○.

[Table 2]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example No. Resin or polymer Acid generator Quencher Example 1 R5 / 13.5 parts S / 0.1 part Q / 0.019 parts Example 2 R6 / 13.5 parts S / 0.1 parts Q / 0.019 parts Example 3 R7 / 13.5 parts S / 0.1 part Q / 0.019 part Example 4 R8 / 13.5 parts S / 0.1 part Q / 0.024 parts Example 5 R8 / 13.5 parts S / 0.07 parts Q / 0.017 parts Example 6 R8 / 13.5 parts S / 0.13 parts Q / 0.031 Example 7 R6 / 6.75 part R1 / 3.375 part R2 / 3.375 S / 0.07 part Q / 0.017 part Example 8 R6 / 6.75 part R1 / 3.375 part R3 / 3.375 part S / 0.07 part Q / 0.017 part ――――――――――――――――――――――――――――――――――
Comparative Example 1 R1 / 13.5 parts S / 0.1 part Q / 0.024 parts Comparative Example 2 R1 / 6.75 parts R2 / 6.75 parts S / 0.1 parts Q / 0.024 parts Comparative Example 3 R1 / 6.75 parts R3 / 6.75 parts S / 0.1 parts Q /0.024 part comparison example 4 R4 / 13.5 part S / 0.1 part Q / 0.024 part━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ━━━━━━

[Table 3]
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example No. Coating properties Resolution Resolution Effective sensitivity Crack resistance Heat resistance

Example 1 ○ ○ 400 msec Δ Δ
Example 2 ○ ○ 370 msec ○ △
Example 3 ○ ○ 380 msec ○ ○
Example 4 ○ ○ 490 msec ○ ○
Example 5 ○ ○ 450 msec ○ ○
Example 6 ○ ○ 490 msec ○ ○
Example 7 ○ ○ 460 msec Δ Δ
Example 8 ○ ○ 520 msec Δ Δ
――――――――――――――――――――――――――――――――――――――
Comparative Example 1 × ○ 220 msec × ×
Comparative Example 2 × ○ 190 msec × ×
Comparative Example 3 ○ ○ 205 msec × ×
Comparative Example 4 20 μm line and space was not resolved.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  As is apparent from Table 3, the resists of Examples 1 to 8, which are chemically amplified positive resist compositions containing a novel cross-linked resin and an acid generator, are excellent in coatability, resolution and effective sensitivity. There was no problem in practical use, and the results showed excellent heat resistance and crack resistance compared to the resists of Comparative Examples 1 to 4.

Claims (9)

  (A) a poly (hydroxystyrene) polymer in which a part of hydrogen of a phenolic hydroxyl group is substituted with an acetal type residue and a novolac polymer, a compound containing at least two vinyl ether groups in one molecule; A chemically amplified positive resist composition comprising a resin obtained by reaction and (B) an acid generator. A poly (hydroxystyrene) polymer in which a part of hydrogen of a phenolic hydroxyl group is substituted with an acetal type residue has a structural unit represented by the formula (I) and a structural unit represented by the formula (Ib). The chemically amplified positive resist composition according to claim 1, which is a polymer.

(In Formula (I), R ¹ represents an alkyl having 1 to 4 carbon atoms, R ² represents a cycloalkyl group of the alkyl group carbon atoms or 5 to 7 1 to 6 carbon atoms. Further, R ¹ And R ² together may form a trimethylene chain or a tetramethylene chain.)

  The chemically amplified positive resist composition according to claim 1 or 2, wherein the poly (hydroxystyrene) polymer of component (A) is a poly (p-hydroxystyrene) polymer. A compound containing at least two vinyl ether groups in one molecule is represented by the formula (IIy)

(In formula (IIy), X represents a divalent hydrocarbon group having 2 to 12 carbon atoms which may include an aliphatic cyclic structure.)
The chemically amplified positive resist composition according to any one of claims 1 to 3, which is a compound represented by the formula: The acid generator of component (B) is represented by formula (IIIa) or formula (IIIb)

(IIIa)

(IIIb)
(In Formula (IIIa) and Formula (IIIb), R ³ represents a hydrocarbon group which may have a substituent containing an oxygen atom or a nitrogen atom, or may be substituted with a halogen atom). The chemically amplified positive resist composition according to claim 1, which is a sulfonic acid oxime compound shown.   A poly (hydroxystyrene) polymer in which part of hydrogen of a phenolic hydroxyl group is substituted with an acetal type residue and a novolak polymer are reacted with a compound containing at least two vinyl ether groups in one molecule. Obtained resin. The resin according to claim 6, wherein the poly (hydroxystyrene) polymer in which part of hydrogen of the phenolic hydroxyl group is substituted with an acetal type residue is a polymer having a structural unit represented by the formula (I).

(In Formula (I), R ¹ represents an alkyl having 1 to 4 carbon atoms, R ² represents a cycloalkyl alkyl or a C 5-7 having 1 to 6 carbon atoms. Also, R ¹ and R ² may form a trimethylene chain or a tetramethylene chain together.)   The resin according to claim 6 or 7, wherein the poly (hydroxystyrene) polymer is a poly (p-hydroxystyrene) polymer. A compound containing at least two vinyl ether groups in one molecule is represented by the formula (IIy)

(In formula (IIy), X represents a divalent hydrocarbon group having 2 to 12 carbon atoms which may include an aliphatic cyclic structure.)
The resin according to any one of claims 6 to 8, which is a compound represented by the formula: