JP2000066400A - Positive photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure high resolving power and superior dry etching resistance by using a specified resin, a compd. which generates an acid when irradiated with active light or radiation and a solvent. SOLUTION: The positive photoresist compsn. contains (a) a copolymer having structural units of formulae I, II and III, (b) a compd. which generates an acid when irradiated with active light or radiation and (c) a solvent. In the formulae I-III, R1 and R2 may be the same or different and are each H or 1-3C alkyl and X is a divalent org. group. In the formula II, R1' and R2' may be the same or different and are each H or 1-4C alkyl, W is a divalent org. group and R3' is chain alkyl which may have substituents having 11-20 carbon atoms in total, aryl which may have substituents having 11-30 carbon atoms in total, aralkyl which may have substituents having 12-30 carbon atoms in total or the like.

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 generates an acid in the exposed area by irradiation with radiation such as far 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.

Examples of such a combination include a combination of a compound capable of generating an acid by photolysis with an acetal or an O, N-acetal compound (JP-A-48-89003) or a combination of an orthoester or an amide acetal compound ( JP-A-51-120714), a combination with a polymer having an acetal or ketal group in the main chain (JP-A-53-127714).
133429), a combination with an enol ether compound (JP-A-55-12995), a combination with an N-acyliminocarbonate compound (JP-A-55-126236), a combination with a polymer having an orthoester group in the main chain. (JP-A-56-17345), a combination with a tertiary alkyl ester compound (JP-A-60-3625), a combination with a silyl ester compound (JP-A-60-1725).
10247 gazette) and a combination with a silyl ether compound (JP-A-60-37549, JP-A-60-121)
446 gazette) and the like. 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 to solubilize in alkali are disclosed in, for example, JP-A-59-45439 and JP-A-60-3625. JP-A-62-229242, JP-A-63-27829, JP-A-63-362
40, JP-A-63-250642, Polym.Eng.
Sce., 23, 12 (1983); ACS. Sym. 242, 11 (198
4); Semiconductor World 1987, November, p. 91; M
acromolecules, 21, 21475 (1988); SPIE, 920, 42
Page (1988) and the like, a combination system of a compound generating an acid upon exposure to light and an ester or carbonate compound of a tertiary or secondary carbon (eg, t-butyl, 2-cyclohexenyl). . These systems also have high sensitivity,
In addition, since the absorption in the Deep-UV region is smaller than that of the naphthoquinonediazide / novolak resin system, it can be an effective system 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. Japanese Patent Application Laid-Open No. Hei 8
JP-A-123032 discloses a photoresist composition using a terpolymer containing a group substituted with an acetal group. Further, JP-A-5-113667, JP-A-6-266112, and JP-A-6-289608
JP-A-7-209868 discloses a photoresist composition comprising a hydroxystyrene and a (meth) acrylate copolymer. However, these resist compositions have a remarkable dimensional change of the resist pattern with respect to a post-exposure time delay (hereinafter abbreviated as PED) from exposure to post-baking, and improvement has been desired from the viewpoint of resolution.

Further, JP-A-8-253534 discloses a photoresist composition using a partially crosslinked polymer containing a group substituted with an acetal group.
Japanese Patent Application Publication No. JP-A-5-2005 discloses a radiation-sensitive composition comprising a polymer having a specific acid-cleavable acetal group in a polymer main chain as a crosslinking member between two or more polymer main chains. No. 31310 discloses a radiation-sensitive resin composition containing a copolymer having specific repeating units (1) and (2) and a branched chain unit. JP-A-10-31310 discloses a photoresist composition containing a polymer substituted with a butoxy group or an acetal group and having a partially crosslinked structure. However, these photoresist compositions are unsatisfactory in performance such as sensitivity and resolution, and further improvement has been desired. In addition, these compositions have poor resistance to the formed resist during dry etching performed after exposure and development, and it has been desired to improve this problem.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a chemically amplified positive photoresist composition having high resolution and excellent dry etching resistance. Still another object of the present invention is to eliminate the standing wave,
An object of the present invention is to provide an excellent chemically amplified positive photoresist composition.

[0008]

Means for Solving the Problems In view of the present situation, the present inventors have made intensive studies and as a result, have found that a resin comprising at least three specific structural units, a compound and a solvent which generate an acid upon irradiation with actinic rays or radiation. It has been found that the use of such a positive photoresist composition has a high resolution and can solve the problem of dry etching resistance, and has completed the present invention. That is, the positive photoresist composition according to the present invention has the following constitution. (1) (a) a copolymer A having structural units represented by the following general formulas (I), (II) and (III), and (b) a compound capable of generating an acid upon irradiation with actinic rays or radiation, And (c) a solvent containing a solvent.

[0009]

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In the general formulas (I) to (III), R ₁ and R
₂ may be the same or different and represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X represents a divalent organic group. In the general formula (II), R ′ ₁ and R ′ ₂ may be the same or different and each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; W represents a divalent organic group; ' ₃ is 1 carbon
A chain alkyl group which may have 1 to 20 substituents, a cyclic alkyl group which may have a substituent having 11 to 20 carbon atoms in total, and a substituent which has 11 to 30 carbon atoms in total. It represents a good aryl group or an aralkyl group which may have a substituent having 12 to 30 carbon atoms in total. (2) R ′ _{3 in} the general formula (II) is an aryl group which may have a substituent having a total of 11 to 30 carbon atoms, or a total of 12 to 3 carbon atoms.
The positive photoresist composition according to the above (1), which represents an aralkyl group optionally having 0 substituents. (3) The copolymer A of the above (a) further has the following general formula (I)
The positive photoresist composition according to the above (1) or (2), comprising a structural unit represented by V).

[0011]

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In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a methoxy group, or an acetoxy group. (4) The positive electrode according to any of (1) to (3) above, wherein the copolymer A of (a) further contains a structural unit represented by the following general formula (V). -Type photoresist composition.

[0013]

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In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R _{4 to} R ₈ may be the same or different and represent a hydrogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom. m represents an integer of 1 to 6. (5) The copolymer A of (a) is obtained by adding a divinyl ether compound represented by the following general formula (VI) to a copolymer having the structural units represented by the general formulas (I) and (II). The positive photoresist composition according to the above (1), which is obtained by reacting.

[0015]

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In the formula, X is a divalent organic group. (6) The positive photoresist composition according to (5), wherein X in the general formula (VI) is a group selected from the following divalent organic residues.

[0017]

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(7) The compound (1), wherein the compound (b) that generates an acid upon irradiation with actinic rays or radiation is at least one sulfonium salt represented by the following general formula (VII): The positive photoresist composition according to any one of (1) to (6).

[0019]

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In the formula, three R _{9 s} may be the same or different and each represent a hydrogen atom or a branched alkyl group having 3 to 16 carbon atoms. However, at least one is not a hydrogen atom.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. [A] Copolymer A having Structural Units Represented by the General Formulas (I) to (III) In the positive photoresist composition of the present invention, the copolymer A used is the same as the general formula (I) And a structural unit represented by the following general formula (I)
It contains a structural unit represented by I) (hereinafter also referred to as structural unit (II)) and a crosslinking unit represented by the general formula (III) as a structural unit (hereinafter also referred to as structural unit (III)). It is a copolymer. In the copolymer A, the preferable content of each structural unit is such that the structural unit (I) is 40 to
It is 90 mol%, preferably 50 to 80 mol%, and more preferably 50 to 70 mol%. The content of the structural unit (II) in the copolymer A is 5 to 50 mol%, preferably 10 to 50 mol%.
-45 mol%, more preferably 10-40 mol%. The content of the structural unit (III) in the copolymer A is 0.1.
It is 2 to 10 mol%, preferably 0.5 to 7 mol%, more preferably 1 to 5 mol%.

The copolymer A used in the present invention is:
In addition to the general formulas (I) to (III), it may further include a structural unit of the general formula (IV). In this case, the preferable content of the structural unit is such that the structural unit (I) is 40 to 80 mol%, preferably 50 to 80 mol%, and more preferably 50 to 70 mol%.
Mol%, the structural unit (II) is 5 to 50 mol%, preferably 10 to 45 mol%, more preferably 10 to 40 mol%, and the structural unit (III) is 0.2 to 10 mol%. Preferably, it is 0.5 to 7 mol%, more preferably 1 to 5 mol%, and the structural unit (IV) is 5 to 40 mol%, preferably 5 to 30 mol%, more preferably 5 to 20 mol%. It is. The inclusion of the structural unit (IV) in the copolymer A is effective for further improving the resolving power.

Further, the copolymer A used in the present invention may further contain a structural unit of the general formula (V) in addition to the general formulas (I) to (III). In this case, the preferable content of the structural unit is such that the structural unit (I) is 40 to 80 mol%, preferably 50 to 80 mol%, more preferably 50 to 70 mol%, and the structural unit (II) is 5 to 50 mol%. Mol%, preferably 10 to 45 mol%, more preferably 10 to 40 mol%, and the structural unit (III) is 0.2 to 10 mol%, preferably 0.5 to 7 mol%, more preferably 1 to 5 mol%, and the structural unit (V) is 5 to 40 mol%, preferably 5 to 30 mol%, and more preferably 5 to 20 mol%. The inclusion of the structural unit (V) in the copolymer A is effective in preventing the generation of standing waves.

Further, the copolymer A used in the present invention may further contain a structural unit of the general formula (V) in addition to the above-mentioned general formulas (I) to (IV). In this case, the preferable content of the structural unit is such that the structural unit (I) is 40 to 80 mol%, preferably 50 to 80 mol%, and more preferably 50 to 70 mol%.
Mol%, the structural unit (II) is 5 to 49 mol%, preferably 10 to 45 mol%, more preferably 10 to 40 mol%, and the structural unit (III) is 0.2 to 10 mol%. Preferably, it is 0.5 to 7 mol%, more preferably 1 to 5 mol%, and the structural unit (IV) is 5 to 40 mol%, preferably 5 to 30 mol%, more preferably 5 to 20 mol%. And the structural unit (V) is 5 to 40 mol%, preferably 5
-30 mol%, more preferably 5-20 mol%.

In the general formula (I), R ₁ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms (preferably a methyl group), preferably a hydrogen atom.

The alkyl group of R ′ ₁ and R ′ ₂ in the general formula (II) includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s
Examples thereof include an alkyl group having 1 to 4 carbon atoms such as an ec-butyl group and a t-butyl group. The divalent organic group represented by W may preferably have a substituent, and may be a linear, branched or cyclic alkylene group, an arylene group, a heteroarylene group, an aralkylene group, and -S-, -C ( =
O) -, - N (R '4) -, - SO -, - SO 2 -, -
CO ₂ —, —N (R ′ ₄ ) SO ₂ —, or a divalent group obtained by combining two or more of these groups can be exemplified.
Here, R ′ ₄ can be a hydrogen atom or an alkyl group (specific examples of the alkyl group include the same as those described above for R ′ ₁ ).

The chain alkyl having 11 to 20 carbon atoms, preferably 11 to 18 carbon atoms, of R ′ ₃ may be linear or branched, and may be, for example, an n-undecyl group, i -Undecyl group, n-dodecyl group, i-dodecyl group, n-tridecyl group, i-tridecyl group, n-tetradecyl group, i-tetradecyl group, n-pentadecyl group,
i-pentadecyl group, n-hexadecyl group, i-hexadecyl group, n-heptadecyl group, i-heptadecyl group,
Examples thereof include an n-octadecyl group, an i-octadecyl group, an n-nonadecyl group, and an i-nonadecyl group.

The cyclic alkyl having 11 to 20 carbon atoms, preferably 11 to 18 carbon atoms, of R ′ ₃ may be a cyclic alkyl having a substituent or a cyclic alkyl having a substituent. Cycloundecyl, cyclododecyl, cyclotridecyl, cyclotridecyl, cyclotetradecyl, cyclopentadecyl, cyclohexadecyl, cycloheptadecyl, cyclooctadecyl, cyclononadecyl, 4-cyclohexylcyclohexyl Group, 4-n-hexylcyclohexyl group, pentanylcyclohexyl group, hexyloxycyclohexyl group, pentanyloxycyclohexyl group, and the like. Substituted cyclic alkyl groups other than those listed here can also be used within the above range.

[0029] The R _'3 of the carbon atoms 11 to 30, preferably aryl group of 11 to 25 carbon atoms, 4-cyclopentylphenyl group, 4-cyclohexylphenyl group, 4
-Cycloheptenylphenyl group, 4-cyclooctenylphenyl group, 2-cyclopentylphenyl group, 2-cyclohexylphenyl group, 2-cycloheptenylphenyl group, 2-cyclooctanylphenyl group, 3-cyclopentylphenyl group, 3 -Cyclohexylphenyl group, 3-
Cycloheptenylphenyl 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-cycloocta Nyloxyphenyl group, 3-cyclopentyloxyphenyl group, 3-cyclohexyloxyphenyl group, 3-cycloheptenyloxyphenyl group, 3-cyclooctanyloxyphenyl group, 4-n-pentylphenyl group, 4-n-hexyl Phenyl 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, 2,6-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-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-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-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, Examples thereof include a 3-isoboronyloxyphenyl group and a 2-isoboronyloxyphenyl group, and these may be further substituted within the above range, and are not limited to substituents other than the above examples.

[0030] R _'3 of the carbon atoms 12 to 30, preferably Aralkyl 12 to 25 carbon atoms, 4-cyclopentyl-phenylethyl group, 4-cyclohexyl-phenylethyl group, 4-cyclopropyl benzocycloheptenyl phenylethyl group, 4 −
Cyclooctanylphenylethyl group, 2-cyclopentylphenylethyl group, 2-cyclohexylphenylethyl group, 2-cycloheptenylphenylethyl group, 2-cyclooctanylphenylethyl group, 3-cyclopentylphenylethyl group, 3-cyclohexylphenyl Ethyl group, 3-cycloheptenylphenylethyl group, 3-cyclooctanylphenylethyl group, 4-cyclopentyloxyphenylethyl group, 4-cyclohexyloxyphenylethyl group, 4-cycloheptenyloxyphenylethyl group, 4-cyclo Octanyloxyphenylethyl 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-hexylphenylethyl 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-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 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 A 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 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 Group, 3,4-di-n-pentylphenylethyl group, 4-adamantylphenylethyl group, 3-adamantylphenylethyl group, 2-adamantylphenylethyl group, 4-isobornylphenylethyl group, 3-isoboronyl Phenylethyl group, 2-isoboronylphenylethyl group, 4-cyclopentyloxyphenylethyl group, 4-cyclohexyloxyphenylethyl group, 4-
Cycloheptenyloxyphenylethyl group, 4-cyclooctenyloxyphenylethyl group, 2-cyclopentyloxyphenylethyl group, 2-cyclohexyloxyphenylethyl group, 2-cycloheptenyloxyphenylethyl group, 2-cyclooctanyloxy Phenylethyl group, 3-cyclopentyloxyphenylethyl group, 3
-Cyclohexyloxyphenylethyl group, 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-octanyloxyphenylethyl group, 3-n-pentyloxyphenylethyl group, 3-
n-hexyloxyphenylethyl group, 3-n-heptenyloxyphenylethyl group, 3-n-octanyloxyphenylethyl group, 2,6-diisopropyloxyphenylethyl group, 2,3-di-isopropyloxyphenyl Ethyl group, 2,4-di-isopropyloxyphenylethyl group, 3,4-diisopropyloxyphenylethyl group, 2,6-di-t-butyloxyphenylethyl group, 2,3-di-t-butyloxy Phenylethyl 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-butyloxyphenylethyl group, 2,6-di-t-amyloxyphenylethyl group, 2,3-di-t-amyloxyphenylethyl group, 2,4-di-t-amyloxy Phenylethyl 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-
An isobornyloxyphenylethyl group, a 3-isobornyloxyphenylethyl group, a 2-isobornyloxyphenylethyl group, or the above alkyl is a methyl group,
Examples thereof include those substituted with a propyl group, a butyl group, and the like.

Further, as further substituents of the above groups, a hydroxyl group, a halogen atom (fluorine, chlorine, bromine, iodine),
Nitro group, cyano group, the above alkyl group, methoxy group
Alkoxy groups such as ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, t-butoxy group, alkoxycarbonyl groups such as methoxycarbonyl group and ethoxycarbonyl group, and benzyl An aralkyl group such as a group, a phenethyl group or a cumyl group, an aralkyloxy group, an acyl group such as a formyl group, an acetyl group, a butyryl group, a benzoyl group, a cyanamyl group, or a valeryl group; an acyloxy group such as a butyryloxy group; Alkenyloxy group such as vinyloxy group, propenyloxy group, allyloxy group, butenyloxy group, the above aryl group,
Examples include an aryloxy group such as a phenoxy group and an aryloxycarbonyl group such as a benzoyloxy group.

The substituent of R ′ ₃ is preferably an aryl group having 11 to 25 carbon atoms or an aralkyl group having 12 to 25 carbon atoms. These substituents may further have a substituent, provided that the carbon number of the substituted aryl group or the substituted aralkyl group is within this range.

When the copolymer A contains the structural unit represented by the general formula (II), the dry etching resistance of the positive photoresist composition of the present invention is improved.

In the general formula (III), R ₁ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms (preferably a methyl group), preferably a hydrogen atom. X represents a divalent organic residue, and is an optionally substituted hydrocarbon group having 2 to 16 carbon atoms, preferably an optionally substituted alkylene group having 2 to 16 carbon atoms, and 6 to 16 carbon atoms. And an optionally substituted arylene group. Here, examples of the alkylene group include an ethylene group, a propylene group, a butylene group, an isobutylene group, a heptylene group, a hexylene group, and a cyclohexylene group.Examples of the arylene group include a phenylene group and a naphthylene group. it can. X is more preferably cyclohexylene, phenylene, further preferably 1,4-cyclohexylene,
1,4-phenylene is mentioned. Preferred substituents include an alkyl group, a halogen, a hydroxyl group, an amino group,
Alkoxy and the like.

The copolymer A has the above-mentioned general formulas (I) to (III) as essential components, and preferably further contains a structural unit of the general formula (IV). In the general formula (IV), R ₁ is
It is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms (preferably a methyl group), preferably a hydrogen atom. R is preferably a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a methoxy group or an acetoxy group, more preferably a hydrogen atom, a t-butyl group, a methoxy group or an acetoxy group, and more preferably a hydrogen atom or a t-butyl group. And an acetoxy group is particularly preferred. Preferred specific examples of the linear or branched alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a t-butyl group. Can be

The copolymer A has the above-mentioned general formulas (I) to (III) as essential components, and preferably further contains a structural unit of the general formula (V). In the general formula (V), R ₁ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms (preferably a methyl group), and is preferably a hydrogen atom. R _{4 to} R ₈ each independently represent a hydrogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom. Examples of the linear or branched alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group,
n-propyl group, iso-propyl group, n-butyl group,
A sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, and an octyl group are preferable, and a methyl group, an ethyl group,
A so-propyl group and a t-butyl group are more preferred. As the cyclic alkyl group having 1 to 8 carbon atoms, a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group are preferable,
Cyclohexyl groups are more preferred. As the alkoxy group having 1 to 4 carbon atoms, a methoxy group, an ethoxy group, a propoxy group, and a butoxy group are preferable, and a methoxy group and a t-butoxy group are more preferable. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom are preferred, and a chlorine atom is more preferred. R _{4 to} R ₈ each independently represent the above substituent, but it is more preferable that all of R _{4 to} R ₈ are hydrogen atoms or one of R _{4 to} R ₈ is the above alkyl group. . In the general formula (V), m represents an integer of 1 to 6, preferably an integer of 2 to 4, and more preferably 2.

The copolymer A has the above-mentioned general formulas (I) to (III) as essential components, but can further contain structural units of the general formulas (IV) and (V) at the same time. As a method for introducing the structural unit (III) into the copolymer A, a copolymer having the structural units (I) and (II) is exchanged with a monofunctional vinyl ether compound and a corresponding diol compound in the presence of an acidic catalyst in acetal exchange. It can be introduced using a reaction. Further, it can be obtained by reacting a copolymer having the structural units (I) and (II) with a bifunctional divinyl ether compound. In the method by acetal exchange, the introduction rate of the structure of the general formula (III) is not constant, and it is difficult to obtain a target product stably. Therefore, it is more preferable to use a divinyl ether compound. As the divinyl ether compound that can be used, it is preferable to use a divinyl ether compound represented by the general formula (VI). X in the general formula (VI) represents a divalent organic residue, and examples thereof include the same examples as those in the general formula (III). The introduction of the crosslinking using the divinyl ether of the present invention is preferable because the decomposability of the acetal group is appropriately suppressed, the viscosity change and the sensitivity fluctuation of the resist over time are suppressed, and the generation of scum (development residue) can be prevented. .

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 2,000 to 1,000,000, 000-500,000 is more preferable, and 8,000
Particularly preferred is 0 to 100,000. 2,000 molecular weight
If the value is 0 or less, the resist film loss is large, and
If it exceeds 000, the solubility is poor and the resolution tends to be low.

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, Me is a methyl group, Et is an ethyl group, Ph is a phenyl group, tBu is a t-butyl group, A
c represents an acetyl group.

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In the present invention, an alkali-soluble resin not containing an acid-decomposable group in the composition can be used, thereby improving the sensitivity. The alkali-soluble resin containing no acid-decomposable group (hereinafter, simply referred to as an alkali-soluble resin) is a resin that is soluble in alkali, and preferably includes polyhydroxystyrene, novolak resin, and derivatives thereof. A copolymer resin containing a p-hydroxystyrene unit can also be used as long as it is alkali-soluble. Among them, poly (p-hydroxystyrene), poly (p / m-hydroxystyrene)
A copolymer, a poly (p / o-hydroxystyrene) copolymer, and a poly (p-hydroxystyrene-styrene) copolymer are preferably used. Furthermore, poly (4-hydroxy-3-methylstyrene) resin, poly (4-hydroxy-
A poly (alkyl-substituted hydroxystyrene) resin such as a 3,5-dimethylstyrene) resin, and a resin in which a part of the phenolic hydroxyl groups of the above resin is alkylated or acetylated are also preferably used as long as they are alkali-soluble.

Further, when a part of the phenol nucleus (30 mol% or less of the whole phenol nucleus) of the above resin is hydrogenated, the transparency of the resin is improved, which is preferable in terms of sensitivity, resolution, and rectangular formation of profile. . As the alkali-soluble resin used in the present invention, for example, novolak resin,
Hydrogenated novolak resin, acetone-pyrogallol resin,
Polyhydroxystyrene, alkyl-substituted polyhydroxystyrene, poly (hydroxystyrene-N-substituted maleimide) copolymer, partially O-alkylated or O-acylated polyhydroxystyrene, poly (styrene-
Examples thereof include (maleic anhydride) copolymer, carboxyl group-containing methacrylic resin and derivatives thereof, poly (styrene-hydroxystyrene) copolymer, and hydrogenated polyhydroxystyrene, but are not limited thereto.

Particularly preferred alkali-soluble resins for use in the present invention are novolak resins and alkali-soluble resins containing p-hydroxystyrene units (preferably poly (p-hydroxystyrene), poly (p / m-hydroxystyrene)). Copolymer, poly (p / o-hydroxystyrene) copolymer, poly (p-hydroxystyrene-styrene) copolymer, poly (4-hydroxy-3-methylstyrene) resin, poly (4-hydroxy-3) Poly (alkyl-substituted hydroxystyrene) resin, such as poly (alkyl-substituted hydroxystyrene) resin, a resin in which a part of the phenolic hydroxyl groups of the above resin is alkylated or acetylated, a partially hydrogenated polyhydroxystyrene resin, a polyhydroxystyrene resin , With partially hydrogenated novolak resin, partially hydrogenated polyhydroxystyrene resin That.

In the present invention, polyhydroxystyrene is a p-hydroxystyrene monomer, an m-hydroxystyrene monomer, an o-hydroxystyrene monomer and an alkyl having 1 to 4 carbon atoms at the ortho-position from the bonding position of the hydroxyl group of the monomer. This shows a polymer obtained by polymerizing at least one monomer selected from the group consisting of substituted hydroxystyrene monomers.

The novolak resin is obtained by subjecting a predetermined monomer as a main component to addition condensation with an aldehyde in the presence of an acidic catalyst.

As the predetermined monomer, phenol, m
Cresols such as -cresol, p-cresol and o-cresol, xylenols such as 2,5-xylenol, 3,5-xylenol, 3,4-xylenol and 2,3-xylenol, m-ethylphenol, p- Alkylphenols such as ethylphenol, o-ethylphenol, pt-butylphenol, p-octylphenol, 2,3,5-trimethylphenol, p-methoxyphenol, m-methoxyphenol, 3,5-dimethoxyphenol, Alkoxyphenols such as -methoxy-4-methylphenol, m-ethoxyphenol, p-ethoxyphenol, m-propoxyphenol, p-propoxyphenol, m-butoxyphenol and p-butoxyphenol, 2-methyl-4-isopropyl Fenault Bis alkylphenols etc., dihydroxybiphenyl, bisphenol A, phenylphenol, resorcinol, and the hydroxyaromatic compounds of naphthol or the like can be used alone or two or more kinds, but the invention is not limited thereto.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde , O-nitrobenzaldehyde,
m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde,
Furfural and acetal forms thereof can be used, but among these, formaldehyde is preferably used.

These aldehydes are used alone or in combination of two or more. As the acidic catalyst, sulfuric acid, formic acid, acetic acid, oxalic acid and the like can be used. The molecular weight of the alkali-soluble resin is preferably from 2,000 to 1,000,000, and more preferably from 3,000 to 50,000. As the content of the alkali-soluble resin containing no acid-decomposable group,
It is at most 50% by weight, preferably at most 30% by weight, more preferably at most 20% by weight, based on the total of the resin and the acid-decomposable group-containing resin.

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 photodecolorant for dyes, and a photodiscoloration agent. Agents or known light used in micro resists (400 to 200 nm ultraviolet light,
Far ultraviolet rays, particularly preferably g-line, h-line, i-line, KrF
Excimer laser light), ArF excimer laser light, an electron beam, an X-ray, a compound generating an acid by a molecular beam or an ion beam, and a mixture thereof can be appropriately selected and used.

Other compounds used in the present invention that generate an acid upon irradiation with actinic rays or radiation include, for example, SISchlesinger, Photogr. Sci. Eng., 18, 3
87 (1974), TSBetal, Polymer, 21,423 (1980) and the like diazonium salts, U.S. Pat.Nos. 4,069,055 and 4,06
Ammonium salts described in 9,056, Re 27,992, Japanese Patent Application No. 3-140,140, etc., DC Necker et al., Macromolecules, 1
7,2468 (1984), CSWenetal, Teh, Proc.Conf.Rad.Curing
ASIA, p478 Tokyo, Oct (1988), U.S. Pat.No. 4,069,055
No. 4,069,056, etc.
vello etal, Macromorecules, 10 (6), 1307 (1977), Chem.
& Eng.News, Nov. 28, p31 (1988), EP 104,143,
U.S. Patent Nos. 339,049 and 410,201, JP-A-2-150,84
No. 8, iodonium salts described in JP-A-2-296,514 etc.,
JVCrivello etal, Polymer J. 17, 73 (1985), JVCrive
llo etal. J. Org. Chem., 43, 3055 (1978), WRWatt eta
l, J. Polymer Sci., Polymer Chem. Ed., 22, 1789 (1984),
JVCrivello etal, Polymer Bull., 14,279 (1985), JV
Crivello etal, Macromorecules, 14 (5), 1141 (1981), J.
V. Crivello etal, J. PolymerSci., Polymer Chem. Ed., 17,
2877 (1979), European Patent Nos. 370,693, 3,902,114 and 2
Nos. 33,567, 297,443 and 297,442, U.S. Pat.
No. 3,377, No. 161,811, No. 410,201, No. 339,049, No.
No. 4,760,013, No. 4,734,444, No. 2,833,827, Dokoku Patent No. 2,904,626, No. 3,604,580, No. 3,604,581 Sulfonium salts described in JVCrivello et al., Macromorec
ules, 10 (6), 1307 (1977), JVCrivello etal, J. Polymer
Sci., Polymer Chem.Ed., 17, 1047 (1979), etc., selenonium salts, CSWen et al., Teh, Proc. Conf.
ASIA, p478 Tokyo, Oct (1988), etc., onium salts such as arsonium salts, U.S. Pat.No. 3,905,815, JP-B-46-46
05, JP-A-48-36281, JP-A-55-32070, JP-A-60
-239736, JP-A-61-169835, JP-A-61-169837,
JP-A-62-58241, JP-A-62-212401, JP-A-63-7024
No. 3, organic halogen compounds described in JP-A-63-298339, K. Meier et al, J. Rad. Curing, 13 (4), 26 (1986), T.
P. Gill et al, Inorg.Chem., 19, 3007 (1980), D. Astruc, A
Chem. Res., 19 (12), 377 (1896), organometallic / organic halides described in JP-A-2-14145, etc., S. Hayase eta
l, J. Polymer Sci., 25, 753 (1987), E. Reichmanis et al., J.
Pholymer Sci., Polymer Chem. Ed., 23, 1 (1985), QQZhu
etal, J. Photochem., 36, 85, 39, 317 (1987), B. Amit etal,
Tetrahedron Lett., (24) 2205 (1973), DHR Barton et al.
J. Chem Soc., 3571 (1965), PM Collins et al., J. Chem. So
C., Perkin I, 1695 (1975), M. Rudinstein et al, Tetrahedr
on Lett., (17), 1445 (1975), JWWalker etal J. Am. Chem.
Soc., 110, 7170 (1988), SCBusman et al., J. Imaging Tech
nol., 11 (4), 191 (1985), HMHoulihan et al, Macormolecu
les, 21, 2001 (1988), PM Collins et al., J. Chem. Soc., Ch.
em. Commun., 532 (1972), S. Hayase et al, Macromolecules,
18,1799 (1985), E. Reichmanis et al., J. Electrochem. So
c., Solid State Sci. Technol., 130 (6), FMHoulihan et.
al, Macromolcules, 21, 2001 (1988), EP 0290,750
Nos. 046,083, 156,535, 271,851, 0,38
No. 3,343, U.S. Pat.Nos. 3,901,710, 4,181,531, JP-A-60-198538, and photoacid generators having a 0-nitrobenzyl-type protecting group described in JP-A-53-133022, M. TUNOOKA
etal, Polymer Preprints Japan, 35 (8), G. Berner etal,
J.Rad.Curing, 13 (4), WJMijs etal, Coating Techno
l., 55 (697), 45 (1983), Akzo, H. Adachi et al, Polymer Pr
eprints, Japan, 37 (3), European Patent Nos. 0199,672 and 84515
No. 199,672, No. 044,115, No. 0101,122, U.S. Pat.No. 618,564, No. 4,371,605, No. 4,431,774, JP-A-64-18143, JP-A-2-245756, and Japanese Patent Application No. 3- Compounds which generate sulfonic acid upon photolysis, such as the iminosulfonates described in 140109 and the like, and disulfone compounds described in JP-A-61-166544 and the like 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 etal, J. Imaging Sc
i., 30 (5), 218 (1986), S. Kondo et al., Makromol.Chem., Ra.
pid Commun., 9,625 (1988), Y.Yamadaetal, Makromol.Che
m., 152, 153, 163 (1972), JVCrivello etal, J. PolymerS
ci., Polymer Chem. Ed., 17, 3845 (1979), U.S. Pat.
No. 9,137, Dokoku Patent No. 3914407, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038
JP-A-63-163452, JP-A-62-153853, JP-A-63-163452
Compounds described in No. 146029 can be used.

Further, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad etal, Tetrahedron Lett., (47) 4555 (1971),
Compounds that generate an acid by light described in DHR Barton et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and EP 126,712 can also be used.

Among the compounds capable of decomposing upon irradiation with actinic rays or radiation to generate an acid, those which are used particularly effectively are described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PAG)
An S-triazine derivative represented by 2).

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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
Show Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

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

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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 are each independently
It represents a substituted or unsubstituted alkyl group or aryl group.
Preferably, an aryl group having 6 to 14 carbon atoms, 1 to 1 carbon atoms
And substituted derivatives thereof. As a preferred substituent, the aryl group has 1 to 8 carbon atoms.
An alkoxy group, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, a nitro group, a carboxyl group, a mercapto group,
A hydroxy group and a halogen atom, and an alkyl group is an alkoxy group having 1 to 8 carbon atoms, a carboxyl group,
It is an alkoxycarbonyl group.

[0074] 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 via a single bond or a substituent.

Further, a photoacid generator having a small change in performance (T-Top formation, change in line width, etc.) over time from exposure to heat treatment is preferred. As such a photoacid generator, for example, in the general formulas (PAG3) and (PAG4), Ar ₁ , Ar ₂ , and R ^{203 to} R ²⁰⁵ each represent a substituted or unsubstituted aryl group, and Z ⁻ represents 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

The photoresist composition of the present invention is particularly preferred when the photoacid generating compound (b) used is a compound represented by the above general formula (VII), since the jump of an isolated pattern is further improved. . The three R _{9 s} may be the same or different and represent a hydrogen atom or a branched alkyl group having 3 to 16 carbon atoms. However, at least one is not a hydrogen atom.
As the branched alkyl group having 3 to 16 carbon atoms for R ₉ , iso is
-Propyl group, sec-butyl group, iso-butyl group,
A t-butyl group, an iso-pentyl group, a neo-pentyl group, a t-pentyl group, an iso-hexyl group and the like can be mentioned, but any branched alkyl group having a hydrocarbon having 3 to 16 carbon atoms may be used. May be one or more. Desirable R ₉ is an isopropyl group or a t-butyl group. As the photoacid generating compound, it is preferable to use the compound shown in the above definition at least 20% by weight of the total photoacid generating compound used, but other photoacid generating compounds can be mixed according to the purpose.

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

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The above onium salts represented by the general formulas (PAG3) and (PAG4) are known, for example, JWKnapczyk
etal, J. Am. Chem. Soc., 91, 145 (1969), ALMaycok eta
l, J. Org. Chem., 35, 2532, (1970), E. Goethas et al., Bul
l.Soc.Chem.Belg., 73,546, (1964), HM Leicester, JA
me.Chem.Soc., 51,3587 (1929), JVCrivello etal, J.Po
Chem. Ed., 18,2677 (1980), U.S. Pat. Nos. 2,807,648 and 4,247,473, and JP-A-53-101,331.

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

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In the formula, Ar^Three, Ar^FourAre each independently substituted
Or an unsubstituted aryl group. R ²⁰⁶Is replaced or
It represents an unsubstituted alkyl group or aryl group. A is a substitution
Or unsubstituted alkylene, alkenylene, arylene
Shows a substituent group. Specific examples include the compounds shown below.
However, the present invention is not limited to these.

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In the present invention, the compound (b) that generates an acid upon irradiation with actinic rays or radiation is preferably an onium salt, disulfone, 4-position DNQ sulfonic acid ester, or a triazine compound. It is more preferable to use a sulfonium salt having a benzenesulfonic acid anion moiety having a branched alkyl group represented by the general formula (VII).

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 becomes low. If the amount is more than 40% by weight, the light absorption of the resist becomes 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).

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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, N- (2-aminoethyl) morpholine, and the like.

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. Compounds 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; EFTOP EF301, EF303;
EF352 (manufactured by Shin-Akita Chemical Co., Ltd.), MegaFac F1
71, F173 (manufactured by Dainippon Ink Co., Ltd.), Flora
Do FC430, FC431 (Sumitomo 3M Limited)
Made), Asahi Guard AG710, Surflon S-38
2, SC101, SC102, SC103, SC10
Fluorinated surfactants such as 4, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), and organosiloxane polymer KP3
No. 41 (manufactured by Shin-Etsu Chemical Co., Ltd.) or acrylic acid-based or methacrylic acid-based (co) polymerized polyflow No. 41 75, N
o. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like.

These surfactants can be added alone or in some combination. A preferable addition amount is 100 parts of the composition (excluding the solvent).
0.0005 to 0.01 parts by weight with respect to parts by weight. Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green B
G, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (all manufactured by Orient Chemical Industries, Ltd.), Crystal Violet (CI42555), Methyl Violet (CI42535), Rhodamine B (CI45)
170B), malachite green (CI42000),
Methylene blue (CI52015) and the like can be mentioned.

Further, by adding a spectral sensitizer as described below and sensitizing the photoacid generator to be used in a longer wavelength region than the deep ultraviolet where the photoacid generator used has no absorption, the chemically amplified positive resist of the present invention is obtained. Can be made sensitive to i or g rays. 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 that promote the solubility in a developer include polyhydroxy compounds, and preferably include 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 photoresist composition of the present invention is one in which the above-mentioned components are dissolved in a solvent (d) for dissolving and coating on a support. Dichloride, 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, methyl pyruvate, ethyl pyruvate, pyruvate Propyl, N, N- dimethylformamide, dimethyl sulfoxide, N- methylpyrrolidone and tetrahydrofuran. These solvents are used alone or in combination.

The above-described chemically amplified positive photoresist composition is applied on a substrate (eg, a silicon / silicon dioxide coating) such as used in the manufacture of precision integrated circuit devices by spinner,
After coating by an appropriate coating method such as a coater or the like, exposure is performed through a predetermined mask, baking and development are performed, whereby a good resist pattern can be obtained.

As the developer for the chemically amplified positive photoresist composition of the present invention, for example, sodium hydroxide,
Potassium hydroxide, sodium carbonate, sodium silicate,
Inorganic alkalis such as sodium phosphate, sodium metasilicate and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, and triamines such as triethylamine and methyldiethylamine Triamines, alcoholamines such as dimethylethanolamine and triethanolamine, amides such as formamide and acetamide, tetramethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, tetraethylammonium hydroxide, tributylmethylammonium Hydroxide, tetraethanolammonium hydroxide, methyltriethanolammonium hydroxide, benzylmethyldiethanolammonium hydroxide, benzyl Dimethyl ethanol ammonium hydroxide, benzyl triethanolammonium hydroxide, tetrapropylammonium hydroxide, quaternary ammonium salts such as tetrabutylammonium hydroxide, pyrrole, aqueous solutions of alkalis such as cyclic amines such as piperidine.

[0117]

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 Partially Crosslinked Copolymer] 20 g of polyhydroxystyrene (VP8000, Nippon Soda) was mixed with propylene glycol monoethyl ether acetate (PGME).
A) After dissolving in 80 g and heating to 60 ° C., the pressure of the system was gradually reduced to 20 mmHg, and PGMEA and water in the system were azeotropically dehydrated. After azeotropic dehydration, the mixture was cooled to 20 ° C., 0.22 g of divinyl ether compound (B-1) and 6.5 g of vinyl ether compound (C-1) represented by the following formula were added, and 3 mg of p-toluenesulfonic acid was further added. Was added. After the addition, the reaction was carried out for 2 hours, and the acid was neutralized by adding a small amount of triethylamine. Thereafter, ethyl acetate was added to the reaction solution, and the salt was removed by washing with ion-exchanged water. Further, ethyl acetate and water were distilled off from the reaction solution under reduced pressure to obtain a PGMEA solution of a partially crosslinked copolymer A-1 which was a target.

[0118]

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[0119]

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[Synthesis Example A-2 Partially Crosslinked Copolymer] 20 g of poly-p-hydroxystyrene was dissolved in 80 g of PGMEA, heated to 60 ° C., and then gradually depressurized to 20 mmHg.
Then, PGMEA and water in the system were azeotropically dehydrated. After azeotropic dehydration, the mixture was cooled to 20 ° C., and the divinyl ether compound (B
-2) and 0.25 g of vinyl ether (C-2) were added, and 3 mg of p-toluenesulfonic acid was further added.
Thereafter, ethyl acetate was added to the reaction solution, and the salt was removed by washing with ion-exchanged water. Further, ethyl acetate and water were distilled off from the reaction solution under reduced pressure to obtain a PGMEA solution of the partially crosslinked copolymer A-2, which was the target substance.

Synthesis Examples A-3 to A-9 Partially Crosslinked Copolymer Instead of the divinyl ether compound and the vinyl ether compound used in the above synthesis examples, divinyl ether compounds and vinyl ether compounds having a predetermined solid content shown in Table 1 below were used. Except for using, copolymers A-3 to A-7 according to the present invention were obtained in the same manner as in Synthesis Examples A-1 and A-2. With respect to the structure of the obtained copolymer, the number of the corresponding exemplary structure in the specification is shown in the column of polymer structure in Table 1. The composition ratio indicates the mole% of the exemplified structure in order from the left.

[0122]

[Table 1]

[0123]

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[Examples 1 to 7 and Comparative Examples 1 and 2] (Preparation and evaluation of photosensitive composition) PGMEA (propylene glycol monoethyl ether acetate) was prepared by mixing each material shown in Table 2 below so as to have a predetermined solid content. ) Was added while adjusting the amount, and filtered through a 0.2 μm filter to prepare a resist solution (the concentration of the polymer solution was adjusted so that the total amount of PGMEA was 8 g). This resist solution was applied on a silicon wafer using a spin coater, and dried on a vacuum suction type hot plate at 130 ° C. for 60 seconds to obtain a resist film having a thickness of 0.75 μm.

[0125]

[Table 2]

The acid generators and organic base compounds used in the examples are shown below.

[0127]

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The resist film was exposed using a 248 nm KrF excimer laser stepper (NA = 0.53). After exposure, the film was heated on a hot plate at 130 ° C. for 60 seconds, immediately immersed in a 0.26 N aqueous solution of tetramethylammonium hydroxide (TMAH) for 60 seconds, rinsed with water for 30 seconds, and dried. The pattern on the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the performance of the resist. Table 3 shows the results.

[0129]

[Table 3]

The resolving power indicates a critical resolving power at an exposure amount for reproducing a 0.25 μm line-and-space mask pattern, and the dry-etching resistance is determined by performing dry etching by a usual method.
The relative value was evaluated. The closer the numerical value is to 1.0, the better.

As is evident from the results in Table 3, the positive photoresist compositions of the examples according to the present invention each obtained satisfactory results, while the photoresist compositions of the comparative examples did not exhibit resolution. And the dry etching resistance was unsatisfactory. Further, the change in viscosity of the resist solution according to the present invention was tracked, and no change was observed after 3 months at room temperature.

[0132]

According to the present invention, there is provided an excellent chemically amplified positive photoresist composition having high resolution and improved dry etching resistance. Furthermore, an excellent chemically amplified positive photoresist composition having few standing waves is provided. In addition, a change in viscosity of the resist over time can be suppressed, and a stable composition can be provided.

Claims (6)

[Claims] (A) The following general formulas (I), (II) and (I)
II) a copolymer A having a structural unit represented by
A compound that generates an acid upon irradiation with actinic rays or radiation,
And (c) a solvent containing a solvent. Embedded image In the general formulas (I) to (III), R ₁ and R ₂ may be the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X represents a divalent organic group. General formula (II)
In, R _'1, R' _2, which may be the same or different, represent a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms, W represents a divalent organic group, R _'3, the total A chain alkyl group which may have a substituent having 11 to 20 carbon atoms, a cyclic alkyl group which may have a substituent having 11 to 20 carbon atoms, and 11 to 11 carbon atoms
Represents an aryl group optionally having 30 substituents, or an aralkyl group optionally having 12 to 30 carbon atoms. 2. The compound of the formula (II) wherein R ′ ₃ has a total carbon number of 11
2. The positive photoresist composition according to claim 1, wherein the positive photoresist composition represents an aryl group which may have from 30 to 30 substituents or an aralkyl group which may have from 12 to 30 carbon atoms. object. 3. The positive photoresist composition according to claim 1, wherein the copolymer A of (a) further contains a structural unit represented by the following general formula (IV). object. Embedded image In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a methoxy group, or an acetoxy group. 4. A copolymer having the structural unit represented by the general formula (I) or (II) wherein the copolymer A of (a) is added to a divinyl ether represented by the following general formula (VI). The positive photoresist composition according to claim 1, wherein the composition is obtained by reacting a compound. Embedded image In the formula, X represents a divalent organic group. 5. The method according to claim 4, wherein X in the general formula (VI) is a group selected from the following divalent organic residues.
The positive photoresist composition as described in the above. Embedded image 6. The compound according to claim 1, wherein the compound (b) that generates an acid upon irradiation with actinic rays or radiation is at least one sulfonium salt represented by the following general formula (VII). The positive photoresist composition according to any one of the above. Embedded image In the formula, three R _{9 s} may be the same or different and represent a hydrogen atom or a branched alkyl group having 3 to 16 carbon atoms.
However, at least one is not a hydrogen atom.