JP2001194793A - Positive-acting photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive-acting photoresist composition having high resolving power and forming a resist pattern whose side wall is perpendicular while preventing the trailing of the lower part of the pattern. SOLUTION: The positive-acting photoresist composition contains (a) a copolymer A having at least structural units of formulae I, II and III [where R1 and R2 are each H or methyl; R4 is alkyl, aralkyl, aryl or -Y-O-C(=0)-Z (Y is a 1-20C alkylene, and Z is a 1-20C alkyl, a 6-20C aryl or a 7-20C aralkyl); R3 is H or methyl; and X is a group having a saturated condensed polycyclic hydrocarbon or a saturated bridged cyclic hydrocarbon], (b) a compound which generates an acid when irradiated with active light or radiation and (c) a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photoresist composition used for manufacturing semiconductor integrated circuit devices, masks for manufacturing integrated circuits, printed wiring boards, liquid crystal panels, and the like.

[0002]

2. Description of the Related Art As a positive photoresist composition,
There is a chemically amplified resist composition described in U.S. Pat. No. 4,491,628 and European Patent No. 29,139. The chemically amplified positive resist composition produces an acid in the exposed area by irradiation with radiation such as deep ultraviolet light, and the acid-catalyzed reaction causes the active and non-irradiated parts of the active radiation to dissolve in the developing solution. Is a pattern forming material for forming a pattern on a substrate by changing the pattern.

[0003] Examples of such a combination include a combination of a compound that generates an acid by photolysis and an acetal or an O, N-acetal compound (JP-A-48-89003).
Combination with orthoester or amide acetal compound (JP-A-5120714), combination with polymer having an acetal or ketal group in the main chain (JP-A-53-133429), combination with enol ether compound (Japanese Unexamined Patent Publication No. 55-12995), a combination with an N-acyliminocarbonate compound (Japanese Unexamined Patent Publication No. 55-126).
236), a combination with a polymer having an orthoester group in the main chain (JP-A-56-17345), and a combination with a tertiary alkyl ester compound (JP-A-60-1985).
No. 3625), a combination with a silyl ester compound (JP-A-60-10247), and a combination with a silyl ether compound (JP-A-60-37549,
JP-A-60-112446). These have high photosensitivity because the quantum yield exceeds 1 in principle.

Similarly, systems which are stable under aging at room temperature, but are decomposed by heating in the presence of an acid and solubilized in alkali are disclosed in, for example, JP-A-59-45439 and JP-A-60-3625. Gazette, JP-A-62-2229242
JP, JP-A-63-27829, JP-A-63-27829
No. 36240, JP-A-63-250542,
Polym. Eng. Sce., 23, 12 (1983); ACS. Sym. 242,
11 (1984); Semiconductor World 1987, November, page 91; Macromolecules, 21, 1475 (1988); SPI
E, vol. 920, p. 42 (1988), etc., with a compound capable of generating an acid upon exposure to a tertiary or secondary carbon (for example, t-
Butyl, 2-cyclohexenyl) or a carbonate compound. These systems also have high sensitivity, and have a lower absorption in the Deep-UV region than the naphthoquinonediazide / novolak resin system, so that they can be effective systems for shortening the wavelength of the light source.

Japanese Patent Application Laid-Open No. Hei 2-19847 discloses poly (p
(Hydroxystyrene) is disclosed which contains a resin in which the phenolic hydroxyl group of the compound is completely or partially protected by a tetrahydropyranyl group. Japanese Patent Application Laid-Open No. 219957/1992 also discloses a photoresist composition characterized by containing a resin in which 20 to 70% of the phenolic hydroxyl groups of poly (p-hydroxystyrene) are substituted with acetal groups. Have been. Further, JP-A-5-24968
JP-A No. 2 also discloses a photoresist composition using a similar acetal-protected resin.

Further, JP-A-8-123032 discloses a photoresist composition using a terpolymer containing a group substituted with an acetal group. Further, Japanese Patent Application Laid-Open
-113667, JP-A-6-266112, JP-A-6-289608, JP-A-7-209
No. 868 discloses a photoresist composition comprising a hydroxystyrene and a (meth) acrylate copolymer.

JP-A-11-65120 discloses a composition using a copolymer of hydroxystyrene, t-butyl (meth) acrylate and a (meth) acrylate having an alicyclic skeleton having 7 or more carbon atoms. It is shown. JP-A-10-87724 discloses a resin into which an oxy-linked or ester-linked acetal group is introduced. However, these resist compositions have a foot pattern at the bottom of the resist pattern and the sidewall angle of the pattern is tapered so that improvement has been desired.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a positive photoresist composition having a high resolution, preventing footing under a resist pattern, and having a vertical sidewall angle of the pattern. Is to do.

[0009]

Means for Solving the Problems In view of the present situation, the present inventors have conducted intensive studies and as a result, have found that a resin containing at least three specific structural units, a compound capable of generating an acid upon irradiation with actinic rays or radiation, and a solvent. By using a positive photoresist composition containing, having a high resolution, to prevent footing of the lower part of the resist pattern, and obtained the knowledge that it can solve the problem of the tapered shape of the side wall angle of the pattern, The present invention has been completed.

That is, the positive photoresist composition according to the present invention has the following constitution. (1) (a) a copolymer A having at least structural units represented by the following general formulas (I), (II) and (III);
A positive photoresist composition comprising (b) a compound capable of generating an acid upon irradiation with actinic rays or radiation, and (c) a solvent.

[0011]

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In the formulas (I) and (II), R ₁ and R ₂ independently represent a hydrogen atom or a methyl group, and R ₄ has a linear, branched or cyclic substituent. Represents an alkyl group which may be substituted, an aralkyl group which may have a substituent, an aryl group which may have a substituent, or a group represented by the formula (IV).

[0013]

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In the formula (IV), Y represents an optionally substituted alkylene group having 1 to 20 carbon atoms. Z is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may be substituted, an aryl group having 6 to 20 carbon atoms which may be substituted, or 7 to 6 carbon atoms which may be substituted. Represents 20 aralkyl groups.

In the formula (III), R ₃ represents a hydrogen atom or a methyl group, and X represents a saturated condensed polycyclic hydrocarbon which may have a substituent or a saturated bridged ring which may have a substituent. Represents a group having a hydrocarbon.

(2) The positive photoresist composition according to the above (1), wherein the copolymer (a) further contains a structural unit represented by the following general formula (V).

[0017]

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In the formula (V), R ₁ has the same meaning as described in the above (1). R represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a methoxy group or an acetoxy group.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. First, the copolymer A (component (a)) having at least the structural units represented by the general formulas (I) to (III) will be described.

In the positive photoresist composition of the present invention, the copolymer A used includes a structural unit represented by the general formula (I) (hereinafter also referred to as a structural unit (I)) and a compound represented by the general formula (I) (II) and a structural unit represented by the general formula (III) (hereinafter also referred to as a structural unit (III)) as a copolymer component. It is a copolymer.

In the copolymer A, the content of each structural unit is preferably such that the structural unit (I) is 40 to 90 mol%, preferably 50 to 85 mol%, and more preferably 60 to 85 mol%.
~ 85 mol%. The structural unit (I) in the copolymer A
The content of I) is 5 to 40 mol%, preferably 7 to 35 mol%, more preferably 10 to 25 mol%. The content of the structural unit (III) in the copolymer A is 3 to 40 mol%, preferably 5 to 30 mol%, and more preferably 5 to 30 mol%.
20 mol%.

The copolymer A used in the present invention may further contain the structural unit of the general formula (V) in addition to the general formulas (I) to (III). In this case, the content of the structural unit in the copolymer A is preferably such that the structural unit (I) is 40 to 90 mol%, preferably 50 to 85 mol%, and more preferably 60 to 85 mol%. The content of II) is 5 to 40 mol%, preferably 7 to 35 mol%.
Mol%, more preferably 10 to 25 mol%, and the content of the structural unit (III) is 3 to 30 mol%, preferably
It is 5 to 20 mol%, more preferably 5 to 15 mol%. Further, the content of the structural unit (V) in the copolymer A is 5 to 20 mol%, preferably 5 to 15 mol%, more preferably 5 to 10 mol%. The inclusion of the structural unit (V) in the copolymer A is effective for improving the defocus latitude.

In the general formula (I), R ₁ is a hydrogen atom or a methyl group, preferably a hydrogen atom. The hydroxyl group may be located at any of the 2-, 3- and 4-positions, but the 4-position is preferred in terms of sensitivity.

In the general formula (II), R ₂ is a hydrogen atom or a methyl group, preferably a hydrogen atom. The acetal group may be substituted at any of the 2-, 3- and 4-positions, but the 4-position is preferred in terms of sensitivity. Examples of the linear, branched or cyclic alkyl group having 2 to 12 carbon atoms represented by R ₄ include an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group,
Pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecanyl group, dodecanyl group,
Examples thereof include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group, and an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a t-butyl group are particularly preferable. .

As the substituent of the alkyl group, a cyclic alkyl group is preferably substituted at the terminal of the alkyl group, and specific examples thereof include a 2-cyclohexylethyl group having a cyclohexyl group bonded to an ethyl group terminal. Preferably, other substituents include a hydroxyl group, a halogen atom, an amino group,
Examples include a nitro group and an acetyl group. Of these, a hydroxyl group and a chlorine atom are particularly preferred.

The aralkyl group represented by R ₄ is preferably a benzyl group, a phenethyl group, a styryl group, a cinnamyl group, a benzhydryl group, a trityl group or the like. As the substituent, an alkyl group having 1 to 4 carbon atoms, specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group is preferable, and a hydroxyl group, Halogen atom, amino group, nitro group, acetyl group,
An alkoxy group such as a methoxy group is preferred.

The aryl group represented by R ₄ is preferably a phenyl group or a naphthyl group. The substituent has 1 to 1 carbon atoms.
4, an alkyl group, specifically a methyl group, an ethyl group, n-
Propyl group, isopropyl group, n-butyl group, sec-
A butyl group and a t-butyl group are preferable, and a hydroxyl group, a halogen atom, an amino group, a nitro group, an acetyl group, and an alkoxy group such as a methoxy group are preferable. R ₄ preferably also contains a substituent having an ester group represented by the formula (IV).

In the formula (IV), Y represents an optionally substituted alkylene group having 1 to 20 carbon atoms, preferably an alkylene group having 1 to 10 carbon atoms, specifically, a methylene group and an ethylene group. Propylene group, butylene group, pentylene group, hexylene group, heptylene group, octylene group, nonylene group, decanylene group and the like. Among them, ethylene, propylene, butylene and the like are preferable. The alkylene group may be substituted, and examples of the substituent include a methyl group, an ethyl group, a propyl group, a butyl group, a phenyl group, a tolyl group, and a cyclohexyl group.

In formula (IV), Z has 1 to 1 carbon atoms.
20, preferably 7 to 20, more preferably 9 to 9 carbon atoms
Examples of the linear or branched alkyl group of 18 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decanyl group, an undecanyl group, and a dodecanyl group , Tridecanyl group, tetradecanyl group, pentadecanyl group, hexadecanyl group, heptadecanyl group, octadecanyl group, etc., and cyclohexylmethyl group, cyclohexylethyl group, cyclohexylpropyl group, cyclopentylethyl group, cyclopentylpropyl group, norbornylmethyl group, adamantylmethyl group And the like. Substituted alkyl groups other than those described above can be used as long as the number of carbon atoms is within the above range.

Examples of the cyclic alkyl having 3 to 20 carbon atoms, preferably 7 to 20 carbon atoms, more preferably 9 to 18 carbon atoms represented by Z include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclohexyl and cyclohexyl. Heptyl group, cyclooctyl group, cyclononyl group, cyclodecanyl group, cycloheptadecanyl group, cyclooctadecanyl group, 4-cyclohexylcyclohexyl group, 4
-N-hexylcyclohexyl group, pentanylcyclohexyl group, hexyloxycyclohexyl group, pentanyloxycyclohexyl group, 1-methyl-1-cyclohexyl group, 2-methyl-1-cyclohexyl group, norbornyl group, adamantyl group, and the like. Can be. As long as the number of carbon atoms is within the above range, a substituted cyclic alkyl group other than the above can also be used.

The aryl group represented by Z having 6 to 20 carbon atoms, preferably 11 to 20 carbon atoms, more preferably 13 to 20 carbon atoms, includes 4-methylphenyl group, 4-ethylphenyl group, 2,4 A dimethylphenyl group, 2,4
6-trimethylphenyl group, 4-t-butylphenyl group, 4-cyclopentylphenyl group, 4-cyclohexylphenyl group, 4-cycloheptenylphenyl group, 4-
Cyclooctanylphenyl group, 2-cyclopentylphenyl group, 2-cyclohexylphenyl group, 2-cycloheptenylphenyl group, 2-cyclooctenylphenyl group, 3-cyclopentylphenyl group, 3-cyclohexylphenyl group, 3-cyclohep A phenylphenyl group, 3-
Cyclooctanylphenyl group, 4-cyclopentyloxyphenyl group, 4-cyclohexyloxyphenyl group,
4-cycloheptenyloxyphenyl group, 4-cyclooctanyloxyphenyl group, 2-cyclopentyloxyphenyl group, 2-cyclohexyloxyphenyl group, 2
-Cycloheptenyloxyphenyl group, 2-cyclooctanyloxyphenyl group, 3-cyclopentyloxyphenyl group, 3-cyclohexyloxyphenyl group, 3-
Cycloheptenyloxyphenyl group, 3-cyclooctanyloxyphenyl group, 4-n-pentylphenyl group,
4-n-hexylphenyl group, 4-n-heptenylphenyl group, 4-n-octanylphenyl group, 2-n-pentylphenyl group, 2-n-hexylphenyl group, 2-n
-Heptenylphenyl group, 2-n-octanylphenyl group, 3-n-pentylphenyl group, 3-n-hexylphenyl group, 3-n-heptenylphenyl group, 3-n-octanylphenyl group, 2 2,6-di-isopropylphenyl group, 2,3-di-isopropylphenyl group, 2,4-
Di-isopropylphenyl group, 3,4-di-isopropylphenyl group, 3,6-di-t-butylphenyl group,
2,3-di-t-butylphenyl group, 2,4-di-t-
Butylphenyl group, 3,4-di-t-butylphenyl group, 2,6-di-n-butylphenyl group, 2,3-di-
n-butylphenyl group, 2,4-di-n-butylphenyl group, 3,4-di-n-butylphenyl group, 2,6-di-i-butylphenyl group, 2,3-di-i- Butylphenyl group, 2,4-di-i-butylphenyl group, 3,4-
A di-i-butylphenyl group,

2,6-di-t-amylphenyl group, 2,
3-di-t-amylphenyl group, 2,4-di-t-amylphenyl group, 3,4-di-t-amylphenyl group,
2,6-di-i-amylphenyl group, 2,3-di-i-
Amylphenyl group, 2,4-di-i-amylphenyl group, 3,4-di-i-amylphenyl group, 2,6-di-
n-pentylphenyl group, 2,3-di-n-pentylphenyl group, 2,4-di-n-pentylphenyl group, 3,
4-di-n-pentylphenyl group, 4-adamantylphenyl group, 2-adamantylphenyl group, 4-isobornylphenyl group, 3-isobornylphenyl group, 2-isoboronylphenyl group, 4-cyclopentyloxy Phenyl group, 4-cyclohexyloxyphenyl group, 4-cycloheptenyloxyphenyl group, 4-cyclooctanyloxyphenyl group, 2-cyclopentyloxyphenyl group, 2-cyclohexyloxyphenyl group, 2-cycloheptenyloxyphenyl group , 2-cyclooctanyloxyphenyl group, 3-cyclopentyloxyphenyl group, 3-cyclohexyloxyphenyl group, 3-cycloheptenyloxyphenyl group, 3-cyclooctanyloxyphenyl group, 4-n-pentyloxyphenyl group ,
4-n-hexyloxyphenyl group, 4-n-heptenyloxyphenyl group, 4-n-octanyloxyphenyl group, 2-n-pentyloxyphenyl group, 2-n-hexyloxyphenyl group, 2-n -Heptenyloxyphenyl group, 2-n-octanyloxyphenyl group, 3-
n-pentyloxyphenyl group, 3-n-hexyloxyphenyl group, 3-n-heptenyloxyphenyl group,
3-n-octanyloxyphenyl group, 2,6-di-isopropyloxyphenyl group, 2,3-di-isopropyloxyphenyl group, 2,4-di-isopropyloxyphenyl group, 3,4-di-isopropyl Oxyphenyl group, 2,6-di-t-butyloxyphenyl group, 2,3
-Di-t-butyloxyphenyl group, 2,4-di-t-
Butyloxyphenyl group, 3,4-di-t-butyloxyphenyl group, 2,6-di-n-butyloxyphenyl group,

2,3-di-n-butyloxyphenyl group, 2,4-di-n-butyloxyphenyl group, 3,4
-Di-n-butyloxyphenyl group, 2,6-di-i-
Butyloxyphenyl group, 2,3-di-i-butyloxyphenyl group, 2,4-di-i-butyloxyphenyl group, 3,4-di-i-butyloxyphenyl group, 2,6
-Di-t-amyloxyphenyl group, 2,3-di-t-
Amyloxyphenyl group, 2,4-di-t-amyloxyphenyl group, 3,4-di-t-amyloxyphenyl group, 2,6-di-i-amyloxyphenyl group, 2,3
-Di-i-amyloxyphenyl group, 2,4-di-i-
Amyloxyphenyl group, 3,4-di-i-amyloxyphenyl group, 2,6-di-n-pentyloxyphenyl group, 2,3-di-n-pentyloxyphenyl group,
2,4-di-n-pentyloxyphenyl group, 3,4-
Di-n-pentyloxyphenyl group, 4-adamantyloxyphenyl group, 3-adamantyloxyphenyl group, 2-adamantyloxyphenyl group, 4-isobornyloxyphenyl group, 3-isobornyloxyphenyl group, 2- And an isobornyloxyphenyl group. If the number of carbon atoms falls within the above range, substituted aryl groups other than those described above may be used.

The aralkyl group having 7 to 20 carbon atoms, preferably 11 to 20 carbon atoms, more preferably 13 to 20 carbon atoms represented by Z includes a benzyl group, a phenethyl group,
-Methylphenylethyl group, 2,4-dimethylphenylethyl group, 4-cyclopentylphenylethyl group, 4-
Cyclohexylphenylethyl group, 4-cycloheptenylphenylethyl group, 4-cyclooctanylphenylethyl group, 2-cyclopentylphenylethyl group, 2-cyclohexylphenylethyl group, 2-cycloheptenylphenylethyl group, 2-cycloocta Nylphenylethyl group, 3-cyclopentylphenylethyl group, 3-cyclohexylphenylethyl group, 3-cycloheptenylphenylethyl group, 3-cyclooctanylphenylethyl group, 4-cyclopentyloxyphenylethyl group, 4-
Cyclohexyloxyphenylethyl group, 4-cycloheptenyloxyphenylethyl group, 4-cyclooctanyloxyphenylethyl group, 2-cyclopentyloxyphenylethyl group, 2-cyclohexyloxyphenylethyl group, 2-cycloheptenyloxyphenylethyl Group, 2-cyclooctanyloxyphenylethyl group, 3
-Cyclopentyloxyphenylethyl group, 3-cyclohexyloxyphenylethyl group, 3-cycloheptenyloxyphenylethyl group, 3-cyclooctanyloxyphenylethyl group, 4-n-pentylphenylethyl group, 4-n-hexylphenyl Ethyl group, 4-n-heptenylphenylethyl group, 4-n-octanylphenylethyl group, 2-n-pentylphenylethyl group, 2-n
-Hexylphenylethyl group, 2-n-heptenylphenylethyl group, 2-n-octanylphenylethyl group,
3-n-pentylphenylethyl group, 3-n-hexylphenylethyl group, 3-n-heptenylphenylethyl group, 3-n-octanylphenylethyl group, 2,6-di-isopropylphenylethyl group, 2 3,3-di-isopropylphenylethyl group, 2,4-di-isopropylphenylethyl group, 3,4-di-isopropylphenylethyl group,

2,6-di-t-butylphenylethyl group, 2,3-di-t-butylphenylethyl group, 2,4
-Di-t-butylphenylethyl group, 3,4-di-t-
Butylphenylethyl group, 2,6-di-n-butylphenylethyl group, 2,3-di-n-butylphenylethyl group, 2,4-di-n-butylphenylethyl group, 3,4
-Di-n-butylphenylethyl group, 2,6-di-i-
Butylphenylethyl group, 2,3-di-i-butylphenylethyl group, 2,4-di-i-butylphenylethyl group, 3,4-di-i-butylphenylethyl group, 2,6
-Di-t-amylphenylethyl group, 2,3-di-t-
Amylphenylethyl group, 2,4-di-t-amylphenylethyl group, 3,4-di-t-amylphenylethyl group, 2,6-di-i-amylphenylethyl group, 2,3
-Di-i-amylphenylethyl group, 2,4-di-i-
Amylphenylethyl group, 3,4-di-i-amylphenylethyl group, 2,6-di-n-pentylphenylethyl group, 2,3-di-n-pentylphenylethyl group,
2,4-di-n-pentylphenylethyl group, 3,4-
Di-n-pentylphenylethyl group, 4-adamantylphenylethyl group, 3-adamantylphenylethyl group, 2-adamantylphenylethyl group, 4-isobornylphenylethyl group, 3-isoboronylphenylethyl group, 2- Isobornylphenylethyl group, 4-cyclopentyloxyphenylethyl group, 4-cyclohexyloxyphenylethyl group, 4-cycloheptenyloxyphenylethyl group, 4-cyclooctanyloxyphenylethyl group, 2-cyclopentyloxyphenylethyl group A 2-cyclohexyloxyphenylethyl group, 2-
A cycloheptenyloxyphenylethyl group, a 2-cyclooctanyloxyphenylethyl group, a 3-cyclopentyloxyphenylethyl group, a 3-cyclohexyloxyphenylethyl group, a 3-cycloheptenyloxyphenylethyl group,

3-cyclooctanyloxyphenylethyl group, 4-n-pentyloxyphenylethyl group, 4-
n-hexyloxyphenylethyl group, 4-n-heptenyloxyphenylethyl group, 4-n-octanyloxyphenylethyl group, 2-n-pentyloxyphenylethyl group, 2-n-hexyloxyphenylethyl group ,
2-n-heptenyloxyphenylethyl group, 2-n-
An octanyloxyphenylethyl group, a 3-n-pentyloxyphenylethyl group, a 3-n-hexyloxyphenylethyl group, a 3-n-heptenyloxyphenylethyl group, a 3-n-octanyloxyphenylethyl group,
2,6-diisopropyloxyphenylethyl group,
2,3-di-isopropyloxyphenylethyl group,
2,4-di-isopropyloxyphenylethyl group,
3,4-diisopropyloxyphenylethyl group,
2,6-di-t-butyloxyphenylethyl group, 2,
3-di-t-butyloxyphenylethyl group, 2,4-
Di-t-butyloxyphenylethyl group, 3,4-di-
t-butyloxyphenylethyl group, 2,6-di-n-
Butyloxyphenylethyl group, 2,3-di-n-butyloxyphenylethyl group, 2,4-di-n-butyloxyphenylethyl group, 3,4-di-n-butyloxyphenylethyl group, 2, 6-di-i-butyloxyphenylethyl group, 2,3-di-i-butyloxyphenylethyl group, 2,4-di-i-butyloxyphenylethyl group, 3,4-di-i-butyloxy Phenylethyl group, 2,6-di-t-amyloxyphenylethyl group,
2,3-di-t-amyloxyphenylethyl group, 2,
4-di-t-amyloxyphenylethyl group, 3,4-
Di-t-amyloxyphenylethyl group, 2,6-di-
i-amyloxyphenylethyl group, 2,3-di-i-
Amyloxyphenylethyl group, 2,4-di-i-amyloxyphenylethyl group, 3,4-di-i-amyloxyphenylethyl group, 2,6-di-n-pentyloxyphenylethyl group, 2, 3-di-n-pentyloxyphenylethyl group, 2,4-di-n-pentyloxyphenylethyl group,

3,4-di-n-pentyloxyphenylethyl group, 4-adamantyloxyphenylethyl group,
3-adamantyloxyphenylethyl group, 2-adamantyloxyphenylethyl group, 4-isobornyloxyphenylethyl group, 3-isobornyloxyphenylethyl group, 2-isobornyloxyphenylethyl group,
Alternatively, those in which the alkyl in the above-mentioned arylalkyl (aralkyl group) is replaced with a methyl group, a propyl group, a butyl group, or the like can also be mentioned.

Further substituents of the above-mentioned linear, branched or cyclic alkyl group, aryl group and aralkyl group in Z include a hydroxyl group, a halogen atom (fluorine, chlorine, bromine and iodine), a nitro group , Cyano group, the above alkyl group, methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, alkoxy group such as t-butoxy group, methoxycarbonyl Group, alkoxycarbonyl group such as ethoxycarbonyl group, benzyl group, phenethyl group, aralkyl group such as cumyl group, aralkyloxy group, formyl group, acetyl group, butyryl group, benzoyl group, cyanamyl group, acyl group such as valeryl group, Acyloxy group such as butyryloxy group, the above alkenyl group, vinyl Alkoxy group, propenyloxy group include an allyloxy group, an alkenyloxy group such as a butenyloxy group, the above-mentioned aryl group, an aryloxy group such as phenoxy group, aryloxycarbonyl group such as benzoyloxy group.

By setting the number of carbon atoms in a more preferable range, the standing waves and development defects are remarkably improved. Therefore,
An effect different from that described in JP-A-10-87724 can be obtained.

Specific examples of the group represented by formula (IV) are shown below, but it should not be construed that the invention is limited thereto.

[0041]

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[0042]

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[0043]

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[0044]

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In the general formula (III), R ₃ is a hydrogen atom or a methyl group. X represents a saturated condensed polycyclic hydrocarbon group which may have a substituent or a saturated bridged ring hydrocarbon group which may have a substituent.

The saturated condensed polycyclic hydrocarbon group is preferably a C9-20 saturated condensed polycyclic hydrocarbon group, for example, perhydroindene, perhydronaphthalene, perhydroazulene, perhydroheptalene, perhydrobiphenylene. , Perhydroindacene, perhydroacenaphthylene, perhydrofluorene, perhydrophenanthrene, perhydroanthracene, perhydrofluoranthene, perhydrochrysene and the like, but are not limited thereto. The saturated condensed polycyclic hydrocarbon group preferably has 2 to 4 rings. As the substituent, a linear or branched alkyl group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom, an amino group and the like are preferable.

As the saturated bridged ring hydrocarbon group, a saturated bridged ring hydrocarbon group having 7 to 20 carbon atoms is preferable. For example, an adamantyl group, a methyladamantyl group, a norbornyl group, a methylnorbornyl group, an isobornyl group, -Norbornanemethyl group, 3-methyl-2-norbornanemethyl group, 4-pentylbicyclo [2,2,2] octyl group, 1-adamantanemethyl group, 1-adamantaneethyl group, tricyclo [5.2.1.0 ^2,6 ] decanyl group,
Tetracyclo [6.2.1.1 ^3,6 . 0 ^2,7 ] dodecanyl group, hexacyclo [6.6.1.1 ^3,6 . 1 ^10,13 . 0
^2,7 . 0 ^9,14] Although heptadecanyl group, and the like not limited. The saturated bridged ring hydrocarbon group has a bridgehead carbon atom (two tertiary carbon atoms connected by a bridge of carbon atoms and shared by two rings) of 2 to 8, especially 2 to 8
6 is preferable. Among them, adamantyl group, norbornyl group, isobornyl group, tricyclo [5.2.1.0 ^2,6 ] decanyl group, tetracyclo [6.2.1.1 ^3,6 . 0 ^{2, 7]} dodecanyl group is particularly preferable from the viewpoint of resolution. As the substituent, a linear or branched alkyl group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom,
Amino groups and the like are preferred.

Further, in the structural unit represented by the above general formula (V), R ₁ represents a hydrogen atom or a methyl group, R represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, Group or acetyl group. The substitution position of R may be any of the 2-, 3-, and 4-positions, but is preferably the 4-position. As the alkyl group, specifically,
Methyl group, ethyl group, propyl group, isopropyl group, n
-Butyl group, sec-butyl group, t-butyl group and the like, and a methyl group and a t-butyl group are preferable.

The weight average molecular weight of the copolymer A can be measured by gel permeation chromatography (GPC) as a molecular weight (Mw) in terms of polystyrene, and is preferably from 2,000 to 1,000,000. 000 to 500,000, more preferably 2,000 to 500,000.
0 to 30,000 is particularly preferred. 2,000 molecular weight
If the amount is less than the above value, the film thickness of the resist is greatly reduced, and
If it exceeds 000, the solubility is poor and the resolving power tends to decrease.

More specific examples of the structure of the copolymer A are shown below, but the present invention is not limited thereto.
In the following specific examples, Et is an ethyl group, t-Bu
Represents a t-butyl group, and Ac represents an acetyl group.

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[0052]

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[0053]

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[0054]

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[0055]

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The photoacid generator (b) used in the present invention comprises:
A compound that generates an acid upon irradiation with actinic rays or radiation. Examples of the compound used in the present invention, which decomposes upon irradiation with actinic rays or radiation to generate an acid, include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photobleaching agent for dyes, and a photodiscoloration agent. Or known light used in micro-resists (ultraviolet rays of 400 to 200 nm, far ultraviolet rays, particularly preferably g-line, h-line, i-line, K-line).
rF excimer laser light), an ArF excimer laser light, an electron beam, an X-ray, a molecular beam or a compound capable of generating an acid by an ion beam, and a mixture thereof can be appropriately selected and used.

Other examples of the compound capable of generating an acid upon irradiation with actinic rays or radiation used in the present invention include, for example, SI Schlesinger, Photogr. Sci. En.
g., 18,387 (1974), TS Bal et al, Polymer, 21, 42.
3 (1980) and the like diazonium salts, U.S. Pat.No. 4,069,0
No. 55, No. 4,069,056, No. Re 27,992, Japanese Patent Application No. 3-140,1
Ammonium salt described in No. 40, etc., DC Necker et al,
Macromolecules, 17, 2468 (1984), CS Wenetal, Te
h, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct
(1988), U.S. Pat.Nos. 4,069,055 and 4,069,056, phosphonium salts described in JV Crivello et al, Macrom
orecules, 10 (6), 1307 (1977), Chem. & Eng. News, No
v. 28, p31 (1988), EP 104,143, U.S. Pat.
39,049, 410,201, JP-A-2-150848, JP-A-2
-296514 and other iodonium salts, JV Crivello e
t al, Polymer J. 17, 73 (1985), JV Crivello et a
l. J. Org. Chem., 43, 3055 (1978), WR Watt et a
l, J. Polymer Sci., Polymer Chem. Ed., 22, 1789 (19
84), JV Crivello et al, Polymer Bull., 14, 279.
(1985), JV Crivello et al, Macromorecules, 14
(5), 1141 (1981), JV Crivello et al, J. PolymerS
ci., Polymer Chem.Ed., 17,2877 (1979), European Patent No. 3
No. 70,693, No. 3,902,114 No. 233,567, No. 297,443,
No. 297,442, U.S. Pat.Nos. 4,933,377, 161,811,
No. 410,201, No. 339,049, No. 4,760,013, No. 4,734,4
No. 44, No. 2,833,827, Dokoku Patent No. 2,904,626, No. 3,60
No. 4,580, 3,604,581, etc., sulfonium salts described in J.
V. Crivello et al, Macromorecules, 10 (6), 1307 (197
7), JV Crivello et al, J. PolymerSci., Polymer
Selenonium salts described in Chem. Ed., 17, 1047 (1979) and the like,
CS Wen et al, Teh, Proc. Conf.Rad. Curing ASIA,
Onium salts such as arsonium salts described in p478 Tokyo, Oct (1988), etc.

US Pat. No. 3,905,815, JP-B-46-4605
No., JP-A-48-36281, JP-A-55-32070, JP-A-60-2
39736, JP-A-61-169835, JP-A-61-169837, JP-A-62-58241, JP-A-62-212401, JP-A-63-70243
Organohalogen compounds described in JP-A-63-298339, K. Meier et al, J. Rad.Curing, 13 (4), 26 (198
6), TPGill et al, Inorg. Chem., 19, 3007 (1980),
D. Astruc, Acc. Chem. Res., 19 (12), 377 (1896), organometallic / organic halides described in JP-A-2-14145, etc.,
S. Hayase et al, J. Polymer Sci., 25, 753 (1987), E. R.
eichmanis et al, J. Pholymer Sci., Polymer Chem. E
d., 23, 1 (1985), QQ Zhu et al, J. Photochem., 36,
85, 39, 317 (1987), B. Amit et al, Tetrahedron Lett.,
(24) 2205 (1973), DHR Barton et al, J. Chem Soc., 3
571 (1965), PM Collins et al, J. Chem. SoC., Perk
in I, 1695 (1975), M. Rudinstein et al, Tetrahedron
Lett., (17), 1445 (1975), JW Walker et al, J. Am.
Chem. Soc., 110, 7170 (1988), SCBusman et al, J.
Imaging Technol., 11 (4), 191 (1985), HM Houlihan e
t al, Macormolecules, 21, 2001 (1988), PMCollins
et al, J. Chem. Soc., Chem. Commun., 532 (1972), S. Hayas
e et al, Macromolecules, 18, 1799 (1985), E. Reichmanis
et al, J. Electrochem. Soc., Solid State Sci. Tech
nol., 130 (6), FM Houlihan et al, Macromolcules,
21,2001 (1988), European Patent Nos. 0290,750 and 046,083,
No. 156,535, No. 271,851, No. 0,388,343, U.S. Pat.No. 3,901,710, No. 4,181,531, JP-A-60-198538,
A photoacid generator having an o-nitrobenzyl-type protecting group described in JP-A-53-133022 and the like, M. TUNOOKA et al, Polymer P
reprints Japan, 35 (8), G. Berner et al, J. Rad. Curing,
13 (4), WJMijs et al, Coating Technol., 55 (697), 45
(1983), Akzo, H. Adachi et al, Polymer Preprints, Jap
an, 37 (3), European Patent Nos. 0199,672, 84,515, 199,
No. 672, No. 044,115, No. 0101,122, U.S. Pat.No. 618,56
No. 4, No. 4,371,605, No. 4,431,774, JP-A-64-18143
JP-A-2-245756, compounds that generate sulfonic acid upon photodecomposition represented by iminosulfonate and the like described in Japanese Patent Application No. 3-140109, and JP-A-61-166544. Disulfone compounds can be mentioned.

Further, a group that generates an acid by these lights,
Alternatively, a compound having a compound introduced into the main chain or side chain of a polymer, for example, MEWoodhouse et al, J. Am. Chem.
c., 104, 5586 (1982), SPPappas et al, J. Imaging Sc
i., 30 (5), 218 (1986), S. Kondo et al, Makromol.Chem., Ra
pid Commun., 9,625 (1988), Y.Yamada et al, Makromol.C
hem., 152, 153, 163 (1972), JVCrivello et al, J. Polym
erSci., Polymer Chem. Ed., 17, 3845 (1979), U.S. Pat.
No. 3,849,137, Dokoku Patent No. 3914407, JP-A-63-26653,
JP-A-55-164824, JP-A-62-69263, JP-A-63-1460
No. 38, JP-A-63-163452, JP-A-62-153853, JP-A
Compounds described in JP-A-63-146029 can be used.

Further, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad et al, Tetrahedron Lett., (47) 4555 (197
1), DHRBarton et al, J. Chem. Soc., (C), 329 (1970),
Compounds that generate an acid by light described in U.S. Pat. No. 3,779,778 and European Patent 126,712 can also be used.

Among the compounds which decompose upon irradiation with actinic rays or radiation to generate an acid, those which are particularly effectively used are described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PA)
An S-triazine derivative represented by G2).

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In the formula, R ²⁰¹ is a substituted or unsubstituted aryl group or alkenyl group, and R ²⁰² is a substituted or unsubstituted aryl group, alkenyl group, alkyl group, —C (Y) ₃
Is shown. Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0064]

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[0065]

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[0066]

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(2) An iodonium salt represented by the following formula (PAG3) or a sulfonium salt represented by the following formula (PAG4).

[0068]

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Here, the formulas Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group. Preferred substituents include an alkyl group, a haloalkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a nitro group, a carboxyl group, an alkoxycarbonyl group, a hydroxy group, a mercapto group, and a halogen atom.

R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferably, an aryl group having 6 to 14 carbon atoms, 1 to 8 carbon atoms
And substituted derivatives thereof. Preferred substituents are those having 1 to 8 carbon atoms for the aryl group.
An alkoxy group, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, a nitro group, a carboxyl group, a mercapto group,
These are a hydroxy group and a halogen atom, and an alkyl group is an alkoxy group having 1 to 8 carbon atoms, a carboxyl group, or an alkoxycarbonyl group.

[0071] Z ^- represents a counter anion, for example BF ₄ ^{-,
_{AsF 6 -, PF 6 -,}} SbF 6 -, SiF 6 2-, ClO 4 -,
CF ₃ SO ₃ ^-, etc. perfluoroalkane sulfonate anion, pentafluorobenzenesulfonic acid anion, condensed polynuclear aromatic sulfonic acid anion such as naphthalene-1-sulfonic acid anion, anthraquinone sulfonic acid anion, a sulfonic acid group-containing dyes Examples include, but are not limited to:

Further, two of R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ and Ar ¹ and Ar ² may be bonded through a single bond or a substituent.

Further, a photo-acid generator which has little change in performance (T-Top formation, line width change, etc.) over time from exposure to heat treatment is preferred. Such photoacid generator for example, the general formula (PAG3), in ^{(PAG4), Ar 1, Ar} 2, R 203 ~R 205 represents a substituted or unsubstituted aryl group, Z ^{chromatography} is, light Has relatively low diffusivity in the resist film when it is generated as an acid by the irradiation. Specifically, Z- has at least one group selected from the group ^consisting of a branched or cyclic alkyl group or an alkoxy group having 8 or more carbon atoms, or a linear, branched or cyclic carbon group. It has at least two groups selected from the group consisting of an alkyl group or an alkoxy group having 4 to 7 carbon atoms, or a straight or branched alkyl group or an alkoxy group having 1 to 3 carbon atoms. And an anion of benzenesulfonic acid, naphthalenesulfonic acid or anthracenesulfonic acid having at least three groups selected from

Specific examples include the following compounds, but are not limited thereto.

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[0076]

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The above-mentioned onium salts represented by the general formulas (PAG3) and (PAG4) are known, for example, JWKnapczyk
et al, J. Am. Chem. Soc., 91, 145 (1969), ALMaycok et.
al, J. Org. Chem., 35, 2532, (1970), E. Goethas et al, B
ull.Soc.Chem.Belg., 73,546, (1964), HM Leicester, J.
Ame.Chem.Soc., 51,3587 (1929), JVCrivello et al, J.
Polym.Chem.Ed., 18,2677 (1980), U.S. Pat.No. 2,807,648
No. 4,247,473, JP-A-53-101331, and the like.

(3) Disulfone derivatives represented by the following formula (PAG5) or iminosulfonate derivatives represented by the following formula (PAG6).

[0092]

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In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. R ²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. Specific examples include the following compounds, but are not limited thereto.

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[0096]

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[0097]

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In the present invention, the compound (b) which generates an acid upon irradiation with actinic rays or radiation is an onium salt,
It is preferably a disulfone, a 4-position DNQ sulfonic acid ester, or a triazine compound, and more preferably at least one onium salt.

The amount of the compound (b) which decomposes upon irradiation with actinic rays or radiation to generate an acid is usually determined based on the total weight (excluding the coating solvent) of the positive photoresist composition of the present invention. It is used in the range of 0.001 to 40% by weight, preferably 0.01 to 20% by weight, and more preferably 0.1 to 5% by weight. If the amount of the compound that decomposes upon irradiation with actinic rays or radiation to generate an acid is less than 0.001% by weight, the sensitivity is low, and if the amount is more than 40% by weight, the light absorption of the resist is high. This is not preferable because the profile is deteriorated and the process (especially baking) margin is narrowed.

An organic basic compound can be used in the composition of the present invention. This is preferable because the storage stability is improved and the line width change due to PED is reduced. Preferred organic basic compounds that can be used in the present invention are compounds that are more basic than phenol. Among them, a nitrogen-containing basic compound is preferable. Preferred chemical environments include the structures of the following formulas (A) to (E).

[0102]

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Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule, and particularly preferred is a ring structure containing a substituted or unsubstituted amino group and a nitrogen atom. Or a compound having an alkylamino group. Preferred specific examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazol,
Substituted or unsubstituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted Or, unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine and the like can be mentioned. Preferred substituents are an amino group,
An aminoalkyl group, an alkylamino group, an aminoaryl group, an arylamino group, an alkyl group, an alkoxy group, an acyl group, an acyloxy group, an aryl group, an aryloxy group, a nitro group, a hydroxyl group, and a cyano group. As particularly preferred compounds, guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-
Aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino -4-methylpyridine, 2-amino-5
-Methylpyridine, 2-amino-6-methylpyridine,
3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6 -Tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p- Tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline,
Examples include, but are not limited to, N-aminomorpholine and N- (2-aminoethyl) morpholine.

These nitrogen-containing basic compounds are used alone or in combination of two or more. The amount of the nitrogen-containing basic compound to be used is generally 0.001-10 parts by weight, preferably 0.01-5 parts by weight, per 100 parts by weight of the photosensitive resin composition (excluding the solvent). If the amount is less than 0.001 part by weight, the above effects cannot be obtained. On the other hand, if it exceeds 10 parts by weight, the sensitivity tends to decrease and the developability of the unexposed part tends to deteriorate.

The chemically amplified positive resist composition of the present invention may further contain, if necessary, a phenolic OH group which promotes solubility in a surfactant, a dye, a pigment, a plasticizer, a photosensitizer and a developer. A compound having two or more compounds can be contained.

Suitable surfactants include, specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether,
Polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate ,
Sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate and other sorbitan fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxy Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as ethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; F-Top EF301, EF303;
EF352 (manufactured by Shin-Akita Chemical Co., Ltd.), MegaFac F1
71, F173 (manufactured by Dainippon Ink Co., Ltd.), Florade FC430, FC431 (manufactured by Sumitomo 3M Limited),
Asahi Guard AG710, Surflon S-382, SC
101, SC102, SC103, SC104, SC1
05, SC106 (manufactured by Asahi Glass Co., Ltd.) and other fluorinated surfactants, Troysol S-366 (Troy Chemical Co., Ltd.)
Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid-based or methacrylic acid-based (co) polymerized polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like.

These surfactants may be added alone or in some combination. A preferable addition amount is 0.0005 to 0.01 parts by weight based on 100 parts by weight of the composition (excluding the solvent).
Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 1
03, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-5
05 (all manufactured by Orient Chemical Industries, Ltd.), crystal violet (CI42555), methyl violet (CI42535), rhodamine B (CI45170)
B), malachite green (CI42000), methylene blue (CI52015) and the like.

Further, the following spectral sensitizers are added to sensitize the photoacid generator to be used in the wavelength region longer than the far ultraviolet where the photoacid generator used has no absorption, thereby obtaining the chemically amplified positive resist of the present invention. Can be made sensitive to the i or g line. Examples of suitable spectral sensitizers include benzophenone, p, p'-tetramethyldiaminobenzophenone, p, p'-tetraethylethylaminobenzophenone, 2-chlorothioxanthone, anthrone, 9-ethoxyanthracene, anthracene and pyrene. , Perylene,
Phenothiazine, benzyl, acridine orange, benzoflavin, cetoflavin-T, 9,10-diphenylanthracene, 9-fluorenone, acetophenone, phenanthrene, 2-nitrofluorene, 5-nitroacenaphthene, benzoquinone, 2-chloro-4-nitroaniline N-acetyl-p-nitroaniline, p-nitroaniline, N-acetyl-4-nitro-1-naphthylamine, picramide, anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone 1,2-benzanthraquinone, 3-methyl-1,3-diaza-
1,9-benzanthrone, dibenzalacetone, 1,
2-naphthoquinone, 3,3'-carbonyl-bis (5,
7-dimethoxycarbonylcoumarin) and coronene, but are not limited thereto.

Examples of the compound having two or more phenolic OH groups which promote the solubility in a developing solution include polyhydroxy compounds. Preferably, the polyhydroxy compound includes phenols, resorcin, phloroglucin, phloroglucid, 3,4-trihydroxybenzophenone, 2,3,4,4′-tetrahydroxybenzophenone, α, α ′, α ″ -tris (4-hydroxyphenyl) -1,3,5-triisopropylbenzene,
Tris (4-hydroxyphenyl) methane, Tris (4
-Hydroxyphenyl) ethane, 1,1'-bis (4-
(Hydroxyphenyl) cyclohexane.

The chemically amplified positive resist composition of the present invention is one in which the above components are dissolved in a solvent (d) for dissolving and coating on a support. Examples of the solvent that can be used include ethylene dichloride and Cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone,
Methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-
Methoxyethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, ethyl pyruvate, methyl pyruvate , Pyruvate, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc., and these solvents are used alone or in combination.

The above-mentioned chemically amplified positive resist composition is applied onto a substrate (eg, silicon / silicon dioxide coating) which is used in the manufacture of precision integrated circuit devices by an appropriate application method such as a spinner or a coater, and then applied to a predetermined area. A good resist pattern can be obtained by exposing through a mask, baking and developing.

Examples of the developer for the chemically amplified positive resist composition of the present invention include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium phosphate, sodium metasilicate, and aqueous ammonia. Primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, dimethylethanolamine,
Alcoholamines such as triethanolamine, amides such as formamide and acetamide, tetramethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, tetraethylammonium hydroxide, tributylmethylammonium hydroxide, tetraethanolammonium hydroxide , Methyltriethanol ammonium hydroxide,
Quaternary ammonium salts such as benzylmethyldiethanolammonium hydroxide, benzyldimethylethanolammonium hydroxide, benzyltriethanolammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide, and alkalis such as cyclic amines such as pyrrole and piperidine And the like.

[0113]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

Synthesis Example a-1 [Synthesis of Copolymer (R-1)] 32.4 g (0.2 mol) of p-acetoxystyrene and tetracyclo [6.2.1.1 ^3,6 . 0 ^2,7 ] dodecyl-
3.48 g (0.015 mol) of 4-acrylate was dissolved in 120 ml of butyl acetate, and dissolved in a stream of nitrogen and stirred.
At 0 ° C., azobisisobutyronitrile (AIBN)
033 g was added three times every 2.5 hours, and finally another 5
The polymerization reaction was performed by continuing the stirring for an hour. The reaction solution was poured into 1200 ml of hexane to precipitate a white resin. After drying the obtained resin, methanol 150 ml
Was dissolved. 7.7 g of sodium hydroxide (0.1 g
(9 mol) / water (50 ml) was added, and the mixture was heated under reflux for 3 hours for hydrolysis. Then 200 ml of water
And neutralized with hydrochloric acid to precipitate a white resin. This resin was separated by filtration, washed with water and dried. Further, the resultant was dissolved in 200 ml of tetrahydrofuran and dropped and reprecipitated in 5 L of ultrapure water with vigorous stirring. This reprecipitation operation was repeated three times. The obtained resin is dried in a vacuum dryer for 120 minutes.
C. and dried for 12 hours.
Tetracyclododecyl acrylate) copolymer (R-
1) was obtained. The weight average molecular weight (polystyrene conversion value measured by the GPC method) of the obtained resin was 10,000.
Met.

Synthesis Example a-2 [Synthesis of Copolymer (R-2)] In Synthesis Example a-1, tetracyclo [6.2.1.1] was used.
^3,6 . Bicyclo [4.4.0] decyl-3-acrylate 4.6 in place of 0 ^2,7 ] dodecyl-4-acrylate
A poly (p-hydroxystyrene / bicyclodecyl acrylate) copolymer (R-2) was obtained in the same manner except that 3 g (0.022 mol) was used. The weight average molecular weight of the obtained resin was 12,000.

Synthetic Examples a-3 to a-5 Copolymers shown in Table 1 were synthesized in the same manner as in Synthetic Examples a-1 and a-2, except that the amount of the comonomer and the amount charged were changed.

[0117]

[Table 1]

Synthesis Example b-1 [Acid-decomposable polymer (B-
Synthesis of 1)] Resin (R-1) (20 g) is dissolved in propylene glycol methyl ether acetate (PGMEA) (100 g), and this solution is decompressed to 60 ° C. and 20 mmHg, leaving about 20 g of solvent in the system. Distilled off with water. 20 ° C
Cooled to 2.91 g of t-butyl vinyl ether
(0.0291 mol) and 0.05 g of pyridinium p-toluenesulfonic acid salt in cyclohexaneethanol.
A solution dissolved in 67 g (0.0291 mol) was added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 m
An extraction operation was performed by adding 1 l of acetone. After repeating the washing extraction operation three times, the water was distilled off at 60 ° C. and 20 mmHg to remove the water in the system. The concentration of this solution is
It was adjusted to 20% by EA (resin (B-1)).

Synthesis Example b-2 [Acid-decomposable polymer (B-
Synthesis of 2)] Dissolve 20 g of resin (R-2) in 100 g of PGMEA,
This solution was evacuated to 60 ° C. and 20 mmHg to about 20 g.
Was distilled off together with the water remaining in the system. 20
C. and cooled to 2.52 g of ethyl vinyl ether (0.
0349 mol) and 0.05 g of pyridinium p-toluenesulfonate. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times,
Distillation was performed at 20 mmHg to remove water in the system. The concentration of this solution was adjusted to 20% with PGMEA (resin (B-2)).

Synthesis Example b-3 [Acid-decomposable polymer (B-
Synthesis of 3)] Dissolve 20 g of resin (R-3) in 100 g of PGMEA,
This solution was evacuated to 60 ° C. and 20 mmHg to about 20 g.
Was distilled off together with the water remaining in the system. 20
℃, 2-vinyloxyethyl 4- (t-butyl) cyclohexanecarboxylate 5.93g
(0.0233 mol) and 0.05 g of pyridinium p-toluenesulfonate were added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times, 6
Distillation was performed at 0 ° C. and 20 mmHg to remove water in the system. The concentration of this solution was adjusted to 20% with PGMEA (resin (B-3)).

Synthesis Example b-4 [Acid-decomposable polymer (B-
Synthesis of 4)] Dissolve 20 g of resin (R-4) in 100 g of PGMEA,
This solution was evacuated to 60 ° C. and 20 mmHg to about 20 g.
Was distilled off together with the water remaining in the system. 20
℃, cooled to 3.84 g of t-butyl vinyl ether
(0.0383 mol) and 0.05 g of pyridinium p-toluenesulfonate were added to 4.14 g of benzyl alcohol.
(0.0383 mol) was added. 20
After continuing stirring at 2 ° C. for 2 hours, 0.04 g of triethylamine was added to terminate the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times, the water was distilled off at 60 ° C. and 20 mmHg to remove the water in the system. The concentration of this solution was adjusted to 2 with PGMEA.
It was adjusted to 0% (resin (B-4)).

Synthesis Example b-5 [Acid-decomposable polymer (B-
Synthesis of 5)] 20 g of resin (R-5) is dissolved in 100 g of PGMEA,
This solution was evacuated to 60 ° C. and 20 mmHg to about 20 g.
Was distilled off together with the water remaining in the system. 20
Cooled to 4.6 ° C., 4.63 g of isobutyl vinyl ether
(0.0463 mol) and 0.05 g of pyridinium p-toluenesulfonate were added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times, 6
Distillation was performed at 0 ° C. and 20 mmHg to remove water in the system. The concentration of this solution was adjusted to 20% with PGMEA (resin (B-5)).

Synthesis Example b-6 [Acid-decomposable polymer (B-
Synthesis of 6)] Dissolve 12 g of resin (R-1) in 70 g of propylene glycol monomethyl ether acetate (PGMEA),
This solution was evacuated to 60 ° C. and 20 mmHg to about 15 g
Was distilled off together with the water remaining in the system. 20
° C, 2.1 g of ethyl vinyl ether and p-
0.02 g of toluenesulfonic acid was added, and the mixture was stirred at room temperature for 1 hour. Thereafter, 0.02 g of triethylamine was added to the reaction solution to stop the reaction, and ethyl acetate was added to the reaction mixture.
An extraction operation was performed by adding 0 ml and 25 ml of water. After repeating the water washing operation three times, distillation was performed at 60 ° C. and 20 mmHg to remove water in the system. Add this solution to PGMEA
To 20% (resin (B-6)).

Table 2 shows a list of the synthesized acid-decomposable polymers.
Shown in

[0125]

[Table 2]

Synthesis Example c-1 [Acid-decomposable polymer (C-
Synthesis of 1)] 20 g of poly (p-hydroxystyrene) (VP-8000: manufactured by Nippon Soda Co., Ltd.) is dissolved in 100 g of propylene glycol methyl ether acetate (PGMEA),
This solution was evacuated to 60 ° C. and 20 mmHg to about 20 g.
Was distilled off together with the water remaining in the system. 20
C. to 4.17 g of t-butyl vinyl ether
(0.0416 mol) and 0.05 g of pyridinium p-toluenesulfonate in cyclohexaneethanol.
A solution dissolved in 25 g (0.0416 mol) was added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 m
An extraction operation was performed by adding 1 l of acetone. After repeating the washing extraction operation three times, the water was distilled off at 60 ° C. and 20 mmHg to remove the water in the system. The concentration of this solution is PGME
A was adjusted to 20%. (Resin (C-1))

Synthesis Example c-2 [Acid-decomposable polymer (C-
Synthesis of 2)] Poly (p-hydroxystyrene) (VP-8000: manufactured by Nippon Soda Co., Ltd.) (20 g) is dissolved in PGMEA (100 g), and the solution is decompressed to 60 ° C. and 20 mmHg to about 2 mm.
0 g of the solvent was distilled off together with the water remaining in the system.
Cooled to 20 ° C, 3.00 g of ethyl vinyl ether
(0.0416 mol) and 0.05 g of pyridinium p-toluenesulfonate were added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times, 6
Distillation was performed at 0 ° C. and 20 mmHg to remove water in the system. The concentration of this solution was adjusted to 20% with PGMEA (resin (C-2)).

Synthesis Example c-3 [Acid-decomposable polymer (C-
Synthesis of 3)] Poly (p-hydroxystyrene) (VP-8000: manufactured by Nippon Soda Co., Ltd.) (20 g) was dissolved in PGMEA (100 g), and the solution was decompressed to 60 ° C. and 20 mmHg to about 2 mm.
0 g of the solvent was distilled off together with the water remaining in the system.
After cooling to 20 ° C, 2-vinyloxyethyl 4- (t
-Butyl) cyclohexanecarboxylate 8.47 g
(0.0333 mol) and 0.05 g of pyridinium p-toluenesulfonate were added. After continuing stirring at 20 ° C. for 2 hours, 0.04 g of triethylamine was added to stop the reaction. 100 ml of ethyl acetate was added to the reaction mixture, and 50 ml of water and 3 ml of acetone were further added to perform an extraction operation. After repeating the washing extraction operation three times, 6
Distillation was performed at 0 ° C. and 20 mmHg to remove water in the system. The concentration of this solution was adjusted to 20% with PGMEA (resin (C-3)).

Examples and Comparative Examples (Preparation and Evaluation of Radiation-Sensitive Resin Composition) Each material shown in Table 3 below was dissolved in 8 g of PGMEA, and filtered with a 0.1 μm filter to prepare a resin composition solution. (Each resin was used in the PGMEA solution, and the solid content conversion value was shown in the table). Using a spin coater, the resin composition solution was uniformly applied on a hexamethyldisilazane-treated silicon wafer, and heated and dried on a hot plate at 120 ° C. for 90 seconds to form a 0.5 μm resist film. Was formed. This resist film was subjected to pattern exposure using a KrF excimer laser stepper (NA = 0.63) using a line and space mask, and immediately after exposure, heated at 110 ° C. for 90 seconds on a hot plate. The film was further developed with a 2.38% aqueous solution of tetramethylammonium hydroococide at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and dried.

Here, the obtained pattern was observed with a scanning electron microscope, and the performance of the resist was evaluated as follows. The sensitivity was determined by the minimum exposure energy (minimum exposure amount) at which a 0.24 μm line-and-space pattern on the mask gave a 0.24 μm line pattern. The resolving power was represented by the limit resolving power that can be resolved with this minimum exposure amount.
The side wall angle of the pattern was obtained by observing the angle of the side wall of the line pattern of 0.24 μm with a scanning electron microscope and expressing the angle from the substrate surface. The skirting at the bottom of the pattern was evaluated as A when there was no skirting, B when slight skirting was observed, C when remarkable skirting was observed, and D when penetration was observed.

[0131]

[Table 3]

[0132]

Embedded image

[0133]

[Table 4]

As shown in Table 4 above, the compositions of Examples of the present invention were excellent in all of the resolving power, the perpendicularity of the side wall angle, and the absence of footing. On the other hand, the composition of the comparative example was inferior in resolution, particularly in the verticality of the side wall angle and the footing.

[0135]

According to the present invention, it is possible to obtain a chemically amplified positive resist composition having a high resolution and an excellent perpendicularity of the pattern side wall angle and having no footing under the pattern.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA02 AA03 AB15 AB16 AC08 AD03 BE00 BE10 BG00 CB14 CB16 CB17 CB41 CC03 4J002 BC121 FD206 FD207 GP03 4J100 AB02S AB07P AB07Q AB07S AL08R BA02Q BA03P BA15Q BA15R BC04 BC04

Claims (2)

[Claims] (1) (a) The following general formulas (I), (II) and (II)
A positive photoresist composition comprising a copolymer A having at least the structural unit represented by I), (b) a compound capable of generating an acid upon irradiation with actinic rays or radiation, and (c) a solvent. object. Embedded image In the formulas (I) to (II), R ₁ and R ₂ independently represent a hydrogen atom or a methyl group, and R ₄ is an alkyl which may have a linear, branched or cyclic substituent. Represents a group, an aralkyl group which may have a substituent, an aryl group which may have a substituent, or a group represented by the formula (IV). Embedded image In the formula (IV), Y is an optionally substituted carbon number of 1 to 20.
Represents an alkylene group. Z is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may be substituted,
Represents an aryl group having 6 to 20 carbon atoms which may be substituted or an aralkyl group having 7 to 20 carbon atoms which may be substituted. In the formula (III), R ₃ represents a hydrogen atom or a methyl group, and X represents a saturated condensed polycyclic hydrocarbon which may have a substituent or a saturated bridged ring hydrocarbon which may have a substituent. Represents a group having 2. The positive photoresist composition according to claim 1, wherein the copolymer (a) further contains a structural unit represented by the following general formula (V). Embedded image In the formula (V), R ₁ has the same meaning as in claim 1. R represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a methoxy group or an acetoxy group.