JPH07281431A - Positive type photoresist composition - Google Patents

Abstract

PURPOSE:To obtain a photoresist compsn. having high resolving power, accurately reproducing the dimensions of a mask and forming a resist pattern whose cross-sectional shape has a high aspect ratio by incorporating specified novolak resin into alkali-soluble novolak resin. CONSTITUTION:In a positive type photoresist compsn. contg. alkalisoluble novolak resin and a 1,2-quinonediazido compd., novolak resin obtd. by condensing a mixture contg. at least one kind of phenol represented by formula I and at least one kind of compd. represented by formula II with aldehydes is incorporated into the alkali-soluble novolak resin. In the formula I each of R1-R3 is H, hydroxyl, halogen, alkyl, alkoxy, etc. In the formula II, each of R4 and R5 is H, hydroxyl, halogen, alkyl, cycloalkyl, hydroxyalkyl, alkoxy, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation sensitive photoresist composition, and more particularly to a photoresist composition for microfabrication having a high resolution and sensitivity and a good pattern cross-sectional shape. It is a thing. The positive type photoresist according to the present invention is a semiconductor wafer,
It is applied to a substrate of glass, ceramics, metal or the like by a spin coating method or a roller coating method to a thickness of 0.5 to 3 μm. Then, it is heated and dried, and a circuit pattern or the like is printed through an exposure mask by ultraviolet irradiation or the like and developed to form a positive image. Further, by etching with this positive image as a mask, the pattern can be processed on the substrate. IC is a typical application field
And other semiconductor manufacturing processes, liquid crystal, circuit board manufacturing such as thermal heads, and other photo-ablation processes.

[0002]

2. Description of the Related Art As a positive photoresist composition,
Generally, a composition containing an alkali-soluble resin and a naphthoquinonediazide compound as a photosensitive material is used. For example, US Pat. No. 3,666,473 as “Novolak type phenol resin / naphthoquinone diazide substituted compound”.
No., USP-4,115,128 and USP-4,17
No. 3,470, etc., and the most typical composition is "cresol-formaldehyde novolak resin /
An example of "trihydroxybenzophenone-1,2 naphthoquinone diazide sulfonate" is Thompson "Introduction Tou Microlithography".
(LF Thompson "Intro-ducti
on to Microlitho-graphics ")
(ACS Publication, No. 219, P112 to 121). Novolac resin as a binder is particularly useful for this application because it can be dissolved in an aqueous alkaline solution without swelling, and when it is used as a mask for etching, it gives high resistance to plasma etching. Is. Further, the naphthoquinonediazide compound used for the photosensitive material acts as a dissolution inhibitor which reduces the alkali solubility of the novolak resin by itself, but when it is decomposed by being irradiated with light, an alkali-soluble substance is produced and rather the alkali solubility of the novolak resin is reduced. It is unique in that it acts to enhance it, and is particularly useful as a photosensitive material for a positive photoresist because of its large change in properties with respect to light. From this point of view, many positive photoresists containing a novolak resin and a naphthoquinonediazide photosensitive material have been developed and put to practical use from the viewpoint of 1.5 μm to 2 μm.
We have achieved sufficient results in line width processing up to about μm.

However, the degree of integration of integrated circuits is increasing more and more, and in the manufacture of semiconductor substrates such as VLSIs,
It is becoming necessary to process an ultrafine pattern having a line width of μm or less. In such applications, a photoresist having a particularly high resolution, a high pattern shape reproducibility that accurately copies the shape of the exposure mask, and a high sensitivity from the viewpoint of high productivity is required, and the conventional positive photoresist described above is applicable. The reality is that we cannot do it.

[0004]

Therefore, the object of the present invention is to (1) particularly in the manufacture of semiconductor devices.
A positive photoresist composition having high resolution,
(2) A positive photoresist composition that accurately reproduces mask dimensions over a wide range of photomask line width,
(3) A positive photoresist composition capable of forming a resist pattern having a cross-sectional shape having a high aspect ratio in a pattern having a line width of 1 μm or less, (4) a pattern having a shape in which the side wall of the pattern cross section is nearly vertical. An object of the present invention is to provide a positive photoresist composition to be obtained, (5) a positive photoresist composition having a wide development latitude, and (6) a positive photoresist composition in which a resist image obtained has excellent heat resistance.

[0005]

Means for Solving the Problems The inventors of the present invention found that the above object can be achieved by using a specific alkali-soluble novolac resin and a quinonediazide compound, as a result of intensive studies in consideration of the above-mentioned characteristics. The present invention has been completed based on the above. That is, the object of the present invention is to provide a positive photoresist composition containing an alkali-soluble novolac resin and a 1,2-quinonediazide compound, wherein the alkali-soluble novolac resin is a phenol compound represented by the following general formula [1]. A positive type photoresist composition comprising a novolak resin obtained by condensing an aldehyde with a mixture containing at least one compound represented by the general formula [2]. Achieved

[0006]

[Chemical 3]

Here, R _{1 to} R ₃ may be the same or different and are a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an aryl group, an aralkyl group, an alkoxycarbonyl group or an arylcarbonyl group, R _{4 to} R ₅ may be the same or different and represent a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkenyl group, an aryl group or an aralkyl group. Hereinafter, the present invention will be described in detail.

In R _{1 to} R ₃ of the above general formula [1], the halogen atom is preferably a chlorine atom, a bromine atom or an iodine atom, more preferably a chlorine atom. As the alkyl group, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, a sec-butyl group or a t-butyl group is preferable, and a methyl group is a point of sensitivity. Is more preferable. The alkoxy group has 1 to 4 carbon atoms such as methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group or t-butoxy group. Alkoxy groups are preferred, and methoxy and ethoxy groups are more preferred. The alkenyl group is preferably an alkenyl group having a carbon number of 2 to 4, such as vinyl group, propenyl group, allyl group or butenyl group, more preferably vinyl group and allyl group. The aryl group is preferably a phenyl group, a xylyl group, a toluyl group or a cumenyl group, more preferably a phenyl group. The aralkyl group is preferably a benzyl group, a phenethyl group or a cumyl group, more preferably a benzyl group. The alkoxycarbonyl group is preferably a methoxycarbonyl group or an ethoxycarbonyl group, more preferably a methoxycarbonyl group. A benzoyloxy group is preferred as the arylcarbonyl group.

More specific examples of the phenols represented by the above general formula [1] include phenol, cresols such as o-cresol, m-cresol and p-cresol, 2,5-xylenol, 3,5. -Xylenol,
3,4-xylenol, 2,3-xylenol, 2,4
-Xylenols, xylenols such as 2,6-xylenol, o-ethylphenol, m-ethylphenol,
Alkylphenols such as p-ethylphenol and pt-butylphenol, o-methoxyphenol, m-
Methoxyphenol, p-methoxyphenol, o-ethoxyphenol, m-ethoxyphenol, p-ethoxyphenol, 3,5-dimethoxyphenol, 2-
Alkoxyphenols such as methoxy-4-methylphenol, o-propoxyphenol, m-propoxyphenol, p-propoxyphenol, o-butoxyphenol, m-butoxyphenol, p-butoxyphenol, 2,3,5-trimethylphenol , 3, 4,
Trimethylphenols such as 5-trimethylphenol, 2,3,6-trimethylphenol, o-vinylphenol, m-vinylphenol, p-vinylphenol, o-allylphenol, m-allylphenol, p
-Alkenylphenols such as allylphenol, o-
Arylphenols such as phenylphenol, m-phenylphenol, p-phenylphenol, aralkylphenols such as o-benzylphenol, m-benzylphenol, p-benzylphenol, o-methoxycarbonylphenol, m-methoxycarbonylphenol, Alkoxycarbonylphenols such as p-methoxycarbonylphenol, o-benzoyloxyphenol, m-benzoyloxyphenol, arylcarbonylphenols such as p-benzoyloxyphenol, o-chlorophenol, m-chlorophenol, p-chlorophenol Halogenated phenols such as catechol, resorcinol, hydroquinone, phloroglucinol, polyhydroxybenzenes such as pyrogallol, etc. Kill, but not be limited to these.

Of these, phenol, cresols, xylenols and trimethylphenols are preferable, and m-cresol, p-cresol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol, 2, 3-xylenol and 2,3,5-trimethylphenol are more preferable.

These phenols may be used alone or in combination with 2.
It is possible to mix and use one kind or more, but in order to sufficiently exert the effect of the present invention, it is further preferable to appropriately mix and use three kinds of m-cresol, p-cresol and 2,5-xylenol. preferable.

In R _{4 to} R ₅ of the above general formula [2], the halogen atom is preferably a chlorine atom, a bromine atom or an iodine atom, more preferably a chlorine atom. As the alkyl group, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, a sec-butyl group or a t-butyl group is preferable, and a methyl group is a point of sensitivity. Is more preferable. The cycloalkyl group is preferably a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group or a cyclooctyl group, more preferably a cyclohexyl group. Examples of the alkoxy group are methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, isopropoxy group, n-butoxy group, isobutoxy group, se.
1 carbon atom such as c-butoxy group or t-butoxy group
~ 4 alkoxy groups are preferred, and methoxy and ethoxy groups are more preferred. Vinyl group as the alkenyl group,
An alkenyl group having 2 to 4 carbon atoms such as a propenyl group, an allyl group or a butenyl group is preferable, and a vinyl group and an allyl group are more preferable. A phenyl group as an aryl group,
A xylyl group, a toluyl group, or a cumenyl group is preferable, and a phenyl group is more preferable. The aralkyl group is preferably a benzyl group, a phenethyl group or a cumyl group, more preferably a benzyl group. As the hydroxyalkyl group, a hydroxymethyl group and a hydroxyethyl group are preferable, and a hydroxymethyl group is more preferable.

Specific examples of cyclohexylphenols represented by the general formula [2] are shown below, but the compounds usable in the present invention are not limited to these.

[0014]

[Chemical 4]

Among the specific examples shown above, [2-a],
[2-c], [2-f], [2-g], [2-i] and [2-j] are preferable, and [2-a] and [2-c] are particularly preferable.

The mixing ratio of the phenols represented by the general formula [1] and the cyclohexylphenols represented by the general formula [2] is such that the amount of the cyclohexylphenols necessary to sufficiently exert the effects of the present invention is obtained. It may be used, but is not particularly limited. However, if the ratio of cyclohexylphenols is too high, the sensitivity is lowered.
It is preferable that the amount of the above-mentioned phenols is 60 mol% or more and the amount of the cyclohexylphenol [2] is less than 40 mol%. A more preferable mixing ratio of cyclohexylphenol is 0.1 mol% or more and less than 20 mol%, and more preferably 1 mol% or more and less than 10 mol%.

As a mixture of phenols represented by the general formula [1], which exhibits the effects of the present invention sufficiently, m-
A mixture of three kinds of cresol, p-cresol and 2,5-xylenol is preferable, and it is preferable to mix these with cyclohexylphenol represented by the general formula [2] in the following ratios.

M-cresol: 30 mol% or more and less than 80 mol% p-cresol: 1 mol% or more and less than 40 mol% 2,5-xylenol: 1 mol% or more and less than 40 mol% cyclohexylphenol: less than 40 mol%

More preferably, m-cresol: 40 mol% or more and less than 70 mol% p-cresol: 1 mol% or more and less than 30 mol% 2,5-xylenol: 1 mol% or more and less than 30 mol% cyclohexylphenols: 0 1 mol% or more and less than 20 mol%

More preferably, m-cresol: 50 mol% or more and less than 70 mol% p-cresol: 5 mol% or more and less than 30 mol% 2,5-xylenol: 5 mol% or more and less than 30 mol% cyclohexylphenols: 1 It is not less than 15 mol% and not less than 15 mol%.

As the aldehydes, for example, formaldehyde, paraformaldehyde, trioxane, acetaldehyde, furfural, benzaldehyde, hydroxybenzaldehydes, crotonaldehyde, chloroacetaldehyde and the like can be used. Among them, formaldehyde or paraformaldehyde is usable. Is preferably used. Further, a methylol compound obtained by reacting a phenol represented by the general formula [1] and a cyclohexylphenol represented by the general formula [2] with formaldehyde under a basic condition can be used as a formaldehyde precursor. . These aldehydes may be used alone or in combination of two or more.

As the acidic catalyst used in the condensation reaction, hydrochloric acid,
Sulfuric acid, formic acid, acetic acid, oxalic acid and the like can be used, and oxalic acid is preferred.

The weight average molecular weight of the thus obtained novolak resin is preferably in the range of 2000 to 30000. If it is less than 2000, the film loss of the unexposed area after development is large, and if it exceeds 30,000, the developing speed becomes low and the sensitivity is lowered. The low molecular weight component of the resulting novolak resin was used as described in JP-A-60-45238 and 60-97.
347, 60-140235, and 60-18973.
9, the same 64-14229, JP-A-1-276131, the same 2-60915, the same 2-275955, the same 2-2827.
No. 45, No. 4-101147, No. 4-122938, etc., the performances such as scum and heat resistance are improved when removed by a technique such as fractional precipitation, fractional dissolution, column chromatography and the like. More preferable. The amount of the low molecular weight component to be removed is preferably 20% by weight to 70% by weight, more preferably 30% by weight to 60% by weight. The weight average molecular weight of the novolak resin after the low molecular weight component is removed is preferably in the range of 5,000 to 20,000. Here, the weight average molecular weight is defined as a polystyrene conversion value of gel permeation chromatography (GPC). In addition, the degree of dispersion of the novolac resin (the ratio of the weight average molecular weight Mw to the number average molecular weight Mn, that is, Mw / Mn)
Is preferably 1.5 to 7.0, and more preferably 1.5 to 4.0. When it exceeds 7, the performance such as sensitivity, heat resistance and profile is impaired. On the other hand, if it is less than 1.5, a high-level purification step is required for synthesizing the novolac resin, which is not practically practical and is inappropriate.

In the present invention, 1,2-naphthoquinonediazide sulfonyl esters are used as a photosensitizer. These are polyhydroxy compounds and 1,2-naphthoquinonediazide-5- (and / or -4-) shown below. It is obtained by esterification with a sulfonyl chloride in the presence of a basic catalyst.

Examples of polyhydroxy compounds include 2,
3,4-trihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,3,4-trihydroxy-2 '
-Methylbenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,4,6,3', 4'-penta Hydroxybenzophenone, 2,3,4,2 ', 4'-pentahydroxybenzophenone, 2,3,4,2', 5'-pentahydroxybenzophenone, 2,4,6,3 ', Polyhydroxybenzophenones such as 4 ′, 5′-hexahydroxybenzophenone, 2,3,4,3 ′, 4 ′, 5′-hexahydroxybenzophenone,

2,3,4-trihydroxyacetophenone, 2,3,4-trihydroxyphenyl pentyl ketone, polyhydroxyphenyl alkyl ketones such as 2,3,4-trihydroxyphenylhexyl ketone,

Bis (2,4-dihydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) propane
1, bis ((poly) hydroxyphenyl) alkanes such as bis (2,3,4-trihydroxyphenyl) propane-1, nordihydroguaiaretic acid,

Propyl 3,4,5-trihydroxybenzoate Phenyl 2,3,4-trihydroxybenzoate 3,
Polyhydroxybenzoic acid esters such as phenyl 4,5-trihydroxybenzoate,

Bis (2,3,4-trihydroxybenzoyl) methane, bis (3-acetyl-4,5,6-trihydroxyphenyl) -methane, bis (2,3,4-trihydroxybenzoyl) benzene Bis (polyhydroxybenzoyl) alkanes such as bis (2,4,6-trihydroxybenzoyl) benzene or bis (polyhydroxybenzoyl) aryls,

Ethylene glycol-di (3,5-dihydroxybenzoate), ethylene glycol-di (3,5
Alkylene-di (polyhydroxybenzoates) such as 4,5-trihydroxybenzoates),

2,3,4-biphenyltriol, 3,4,
5-Biphenyltriol 3,5,3 ', 5'-biphenyl tetrol, 2,4,2', 4'-biphenyl tetrol, 2,4,6,3 ', 5'-biphenyl Pentore, 2,4,
6,2 ', 4', 6'-biphenylhexol, 2,3,4,
Polyhydroxybiphenyls such as 2 ′, 3 ′, 4′-biphenylhexol,

Bis (polyhydroxy) sulfides such as 4,4'-thiobis (1,3-dihydroxy) benzene,

Bis (polyhydroxyphenyl) ethers such as 2,2 ', 4,4'-tetrahydroxydiphenyl ether,

Bis (polyhydroxyphenyl) sulfoxides such as 2,2 ', 4,4'-tetrahydroxydiphenylsulfoxide,

Bis (polyhydroxyphenyl) sulfones such as 2,2 ', 4,4'-diphenyl sulfone,

Tris (4-hydroxyphenyl) methane, 4,4 ', 4 "-trihydroxy-3,5,3', 5'-tetramethyltriphenylmethane, 4,4 ', 3", 4 "- Tetrahydroxy-3,5,3 ', 5'-tetramethyltriphenylmethane, 4,4', 2 ", 3", 4 "-pentahydroxy-
3,5,3 ', 5'-tetramethyltriphenylmethane, 2,
3,4,2 ', 3', 4'-hexahydroxy-5,5'-diacetyltriphenylmethane, 2,3,4,2 ', 3', 4 ',
Poly "3,4"-octahydroxy-5,5'-diacetyltriphenylmethane, 2,4,6,2 ', 4', 6'-hexahydroxy-5,5'-dipropionyltriphenylmethane, etc. Hydroxytriphenylmethanes,

3,3,3 ', 3'-tetramethyl-1,1'-
Spirobi-indan-5,6,5 ', 6'-tetrol, 3,
3,3 ′, 3′-tetramethyl-1,1′-spirobi-indane-5,6,7,5 ′, 6 ′, 7′-hexool, 3,3,3 ′,
3'-tetramethyl-1,1'-spirobi-indane-4,
5,6,4 ', 5', 6'-Hexool, 3,3,3 ', 3'-tetramethyl-1,1'-spirobi-indane-4,5,6,
Polyhydroxyspirobi-indanes such as 5 ′, 6 ′, 7′-hexool,

3,3-bis (3,4-dihydroxyphenyl) phthalide, 3,3-bis (2,3,4-trihydroxyphenyl) phthalide, 3 ', 4', 5 ', 6'- Polyhydroxyphthalides such as tetrahydroxyspiro [phthalide-3,9′-xanthene],

Flavono dyes such as morin, quercetin, rutin,

Α, α ', α "-tris (4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α,
α ′, α ″ -tris (3,5-dimethyl-4-hydroxyphenyl) 1,3,5-triisopropylbenzene,
α, α ', α "-tris (3,5-diethyl-4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α, α', α" -tris (3,5-di-n-propyl) −
4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α, α ′, α ″ -tris (3,5-diisopropyl-4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α, α ', α "-Tris (3,5-
Di-n-butyl-4-hydroxyphenyl) 1,3,5-
Triisopropylbenzene, α, α ', α "-tris (3
-Methyl-4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α, α ', α "-tris (3-methoxy-4-hydroxyphenyl) 1,3,5-triisopropylbenzene, α , Α ', α "-Tris (2,4-
Dihydroxyphenyl) 1,3,5-triisopropylbenzene, 1,3,5-tris (3,5-dimethyl-4)
-Hydroxyphenyl) benzene, 1,3,5-tris (5-methyl-2-hydroxyphenyl) benzene,
2,4,6-Tris (3,5-dimethyl-4-hydroxyphenylthiomethyl) mesitylene, 1- [α-methyl-α- (4′-hydroxyphenyl) ethyl] -4-
[Α, α'-bis (4 "-hydroxyphenyl) ethyl]
Benzene, 1- [α-methyl-α- (4'-hydroxyphenyl) ethyl] -3- [α, α'-bis (4 "-hydroxyphenyl) ethyl] benzene, 1- [α-methyl- α- (3 ′, 5′-dimethyl-4′-hydroxyphenyl) ethyl] -4- [α, α′-bis (3 ″, 5 ″ -dimethyl-4 ″ -hydroxyphenyl) ethyl] benzene,
1- [α-methyl-α- (3′-methyl-4′-hydroxyphenyl) ethyl] -4- [α ′, α′-bis (3 ″-
Methyl-4 "-hydroxyphenyl) ethyl] benzene, 1- [α-methyl-α- (3'-methoxy-4'-hydroxyphenyl) ethyl] -4- [α ', α'-bis (3 "-Methoxy-4" -hydroxyphenyl) ethyl]
Benzene, 1- [α-methyl-α- (2 ′, 4′-dihydroxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -hydroxyphenyl) ethyl] benzene, 1-
[Α-Methyl-α- (2 ', 4'-dihydroxyphenyl) ethyl] -3- [α "α'-bis (4" -hydroxyphenyl) ethyl] benzene etc. JP-A-4-25305
The polyhydroxy compound according to item 8,

P-bis (2,3,4-trihydroxybenzoyl) benzene, p-bis (2,4,6-trihydroxybenzoyl) benzene, m-bis (2,3,4-trihydroxybenzoyl) benzene , M-bis (2,4,6-
Trihydroxybenzoyl) benzene, p-bis (2,
5-dihydroxy-3-bromobenzoyl) benzene,
p-bis (2,3,4-trihydroxy-5-methylbenzoyl) benzene, p-bis (2,3,4-trihydroxy-5-methoxybenzoyl) benzene, p-bis (2,3,4-) Trihydroxy-5-nitrobenzoyl)
Benzene, p-bis (2,3,4-trihydroxy-5-
Cyanobenzoyl) benzene, 1,3,5-tris (2,
5-dihydroxybenzoyl) benzene, 1,3,5-tris (2,3,4-trihydroxybenzoyl) benzene, 1,2,3-tris (2,3,4-trihydroxybenzoyl) benzene, 1,2 , 4-tris (2,3,4-trihydroxybenzoyl) benzene, 1,2,4,5-tetrakis (2,3,4-trihydroxybenzoyl) benzene, α, α′-bis (2,3, 4-trihydroxybenzoyl) -p-xylene, α, α ′, α′-tris (2,3,4-
Trihydroxybenzoyl) mesitylene,

2,6-bis- (2'-hydroxy-3 ',
5'-dimethyl-benzyl) -p-cresol, 2,6
-Bis- (2'-hydroxy-5'-methyl-benzyl)
-P-cresol, 2,6-bis- (2'-hydroxy-3 ', 5'-di-t-butyl-benzyl) -p-cresol, 2,6-bis- (2'-hydroxy-5') -Ethyl-benzyl) -p-cresol, 2,6-bis-
(2 ', 4'-Dihydroxy-benzyl) -p-cresol, 2,6-bis- (2'-hydroxy-3'-t-butyl-5'-methyl-benzyl) -p-cresol, 2,
6-bis- (2 ', 3', 4'-trihydroxy-5'-acetyl-benzyl) -p-cresol, 2,6-bis-
(2 ', 4', 6'-trihydroxy-benzyl) -p-
Cresol, 2,6-bis- (2 ', 3', 4'-trihydroxy-benzyl) -p-cresol, 2,6-bis- (2 ', 3', 4'-trihydroxy-benzyl)-
3,5-dimethyl-phenol, 4,6-bis- (4 '
-Hydroxy-3 ', 5'-dimethyl-benzyl) -pyrogallol, 4,6-bis- (4'-hydroxy-3',
5'-dimethoxy-benzyl) -pyrogallol, 2,6
-Bis- (4'-hydroxy-3 ', 5'-dimethyl-benzyl) -1,3,4-trihydroxy-phenol,
4,6-bis- (2 ', 4', 6'-trihydroxy-benzyl) -2,4-dimethyl-phenol, 4,6-bis- (2 ', 3', 4'-trihydroxy-benzyl) ) −
2,5-dimethyl-phenol and the like can be mentioned.

It is also possible to use a low molecular weight phenol resin such as novolak resin.

Further, the following polyhydroxy compounds can also be used.

[0045]

[Chemical 5]

[0046]

[Chemical 6]

Of the above polyhydroxy compounds, the compounds represented by the formulas (5) to (16) are more preferable,
More preferably, formulas (5), (6), (14) and (1
It is the compound shown in 5). These can be used as a mixture, and most preferably, the photosensitive material derived from the compound of formula (5) or (6) and the photosensitive material derived from the compound of formula (14) or (15) are mixed. As a result, the effects of the present invention can be sufficiently exerted.

In the esterification reaction of the photosensitive material, a predetermined amount of polyhydroxy compound and 1,2-naphthoquinonediazide-5- (and / or -4-) sulfonyl chloride are mixed with dioxane, acetone, tetrahydrofuran, methyl ethyl ketone, It is dissolved in a solvent such as N-methylpyrrolidone, chloroform, trichloroethane, trichloroethylene or dichloroethane, and a basic catalyst such as sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, triethylamine, N-methylmorpholine, N-methylpiperazine, 4-dimethylamino is used. Pyridine or the like is added dropwise for condensation. The obtained product is washed with water, purified, and dried.

In the usual esterification reaction, a mixture having different esterification numbers and esterification positions can be obtained. However, by selecting synthesis conditions or the structure of the polyhydroxy compound, only a specific isomer is selected. It can also be esterified. The esterification rate in the present invention is defined as the average value of this mixture.

The esterification rate thus defined can be controlled by the mixing ratio of the raw material polyhydroxy compound and 1,2-naphthoquinonediazide-5- (and / or -4-) sulfonyl chloride. That is, the added 1,
2-naphthoquinonediazide-5- (and / or -4-)
Substantially all of the sulfonyl chloride undergoes an esterification reaction, so the molar ratio of the raw materials may be adjusted in order to obtain a mixture having a desired esterification rate. If necessary,
It is also possible to use 1,2-naphthoquinonediazide-5-sulfonyl chloride and 1,2-naphthoquinonediazide-4-sulfonyl chloride in combination. The reaction temperature in the above method is usually -20 to 60 ° C, preferably 0 to 4
It is 0 ° C.

When the photosensitive compound synthesized by the above method is used as a resin composition, it is used singly or as a mixture of two or more kinds in an alkali-soluble resin. Is 5 to 100 parts by weight, preferably 20 to 60 parts by weight of the compound with respect to 100 parts by weight of the novolak resin.
Parts by weight. If the usage ratio is less than 5 parts by weight, the residual film rate is remarkably lowered, and if it exceeds 100 parts by weight, the sensitivity and the solubility in a solvent are lowered.

The composition of the present invention may further contain a polyhydroxy compound in order to accelerate the dissolution in the developing solution. Preferred polyhydroxy compounds include phenols, resorcin, phloroglucin, 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,3,4,3 ', 4 ', 5'-hexahydroxybenzophenone, acetone-pyrogallol condensation resin, phlorogluside, 2,4,2', 4'-biphenyl tetrol, 4,4'-thiobis (1,3-dihydroxy) benzene, 2,2 ', 4,4'-tetrahydroxydiphenyl ether, 2,2', 4,4'-tetrahydroxydiphenyl sulfoxide, 2,2 ', 4,4'-tetrahydroxydiphenyl sulfone , Tris (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4 ′-(α-methylbenzylidene) bisphenol, α, α ′, α ″ -tris (4 -Hydroxyphenyl) -1,3,5-triisopropylbenzene, α, α ', α "-tris (4-hydroxyphenyl)
-1-ethyl-4-isopropylbenzene, 1,2,2
-Tris (hydroxyphenyl) propane, 1,1,2
-Tris (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2,5,5-tetrakis (4-hydroxyphenyl) hexane, 1,2-tetrakis (4-
Hydroxyphenyl) ethane, 1,1,3-tris (hydroxyphenyl) butane, para [α, α, α ', α'-
Examples thereof include tetrakis (4-hydroxyphenyl)]-xylene. These polyhydroxy compounds can be added in an amount of usually 100 parts by weight or less, preferably 5 to 50 parts by weight or less, based on 100 parts by weight of the quinonediazide compound.

Solvents for dissolving the photosensitive material and the alkali-soluble novolak resin of the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol. Methyl ether acetate, propylene glycol propyl ether acetate, toluene,
Xylene, methyl ethyl ketone, cyclohexanone, 2
-Ethyl hydroxypropionate, 2-hydroxy-2
-Ethyl methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, 3-ethoxypropionic acid Methyl, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate and the like can be used. These organic solvents are used alone or in combination of two or more.

Further, N-methylformamide, N, N-
Dimethylformamide, N-methylacetamide, N,
A high-boiling solvent such as N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzyl ethyl ether can be mixed and used.

A surfactant may be added to the positive photoresist composition of the present invention in order to further improve the coating properties such as striation. Examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, and other polyoxyethylene alkyl ethers, polyoxyethylene octylphenol ether, polyoxyethylene nonyl Polyoxyethylene alkyl allyl ethers such as phenol ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristea Sorbitan fatty acid esters such as oleate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sol Monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, etc., polyoxyethylene sorbitan fatty acid esters nonionic surface active agents such as, Efutotsupu EF
301, EF303, EF352 (manufactured by Shin-Akita Kasei Co., Ltd.),
Megafacs F171, F173 (Dainippon Ink Co., Ltd.)
), Florard FC430, FC431 (Sumitomo 3M Limited), Asahi Guard AG710, Surflon S
-382, SC101, SC102, SC103, SC10
4, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), fluorine-based surfactant, organosiloxane polymer KP341
(Manufactured by Shin-Etsu Chemical Co., Ltd.) or acrylic acid-based or methacrylic acid-based (co) polymerized Polyflow No. 75, No. 95
(Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) and the like can be mentioned. The blending amount of these surfactants is 100% by weight of the alkali-soluble resin and the quinonediazide compound in the composition of the present invention.
It is usually 2 parts by weight or less, preferably 1 part by weight or less, per part by weight. These surfactants may be added alone or in some combinations.

The developer for the positive photoresist composition of the present invention includes sodium hydroxide, potassium hydroxide,
Inorganic alkalis such as sodium carbonate, sodium silicate, sodium metasilicate and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, triethylamine and methyldiethylamine. Tertiary amines such as
Uses an aqueous solution of alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and choline, and cyclic amines such as pyrrole and piperidine, etc. can do. Furthermore, alcohols such as isopropyl alcohol and surfactants such as nonionic surfactants may be added to the aqueous solution of the above alkalis in appropriate amounts.

The positive photoresist composition of the present invention may contain, if necessary, a light absorbing agent, a cross-linking agent, an adhesion aid and the like. The light absorber is added as necessary for the purpose of preventing halation from the substrate and for improving the visibility when applied to the transparent substrate. For example, commercially available light absorbers described in "Technology and Markets of Industrial Dyes" (CMC Publishing) and the Handbook of Dyes (Edited by Synthetic Organic Chemistry), such as CIDe.
sperse Yellow 1,3,4,5,7,8,13,23,31,49,50,51,54,56,
60,64,66,68,79,82,88,90,93,102,114 and 124, CIDis
perse Orange 1,5,13,25,29,30,31,44,57,72 and 73, C.
I. Disperse Red 1,5,7,13,17,19,43,50,54,58,65,72,7
3,88,117,137,143,199 and 210, CIDisperse Violet 4
3, CIDisperse Blue 96, CI Fluorescent Brighteni
ng Agent112, 135 and 163, CI Solvent Yellow 14,16,
33 and 56, CISolvent Orange2 and 45, CISolvent
Red 1,3,8,23,24,25,27 and 49, CI Pigment Green 1
0, CI Pigment Brown 2 and the like can be preferably used. The light absorber is usually 100 parts by weight or less, preferably 50 parts by weight or less, based on 100 parts by weight of the alkali-soluble resin,
More preferably, it is blended in a proportion of 30 parts by weight or less.

The cross-linking agent is added within a range that does not affect the formation of a positive image. The purpose of adding the crosslinking agent is mainly
These include sensitivity adjustment, improvement of heat resistance, and improvement of dry etching resistance. Examples of the cross-linking agent include melamine, benzoguanamine, glycoluril, etc., which are reacted with formaldehyde, or their alkyl modified products, epoxy compounds, aldehydes, azide compounds, organic peroxides, hexamethylenetetramine, etc. be able to. These cross-linking agents can be added in an amount of less than 10 parts by weight, preferably less than 5 parts by weight, based on 100 parts by weight of the photosensitizer. If the amount of the cross-linking agent is more than 10 parts by weight, the sensitivity is lowered and scum (resist residue) is generated, which is not preferable.

The adhesion aid is mainly added for the purpose of improving the adhesion between the substrate and the resist and preventing the resist from being peeled off particularly in the etching step. Specific examples include trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, chlorosilanes such as chloromethyldimethylchlorosilane, trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, dimethylvinylethoxysilane,
Alkoxysilanes such as diphenyldimethoxysilane and phenyltriethoxysilane, hexamethyldisilazane, N, N′-bis (trimethylsilyl) urea, dimethyltrimethylsilylamine, silazanes such as trimethylsilylimidazole, vinyltrichlorosilane, γ-
Silanes such as chloropropyltrimethoxysilane, γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane, benzotriazole, benzimidazole, indazole, imidazole, 2-
Heterocyclic compounds such as mercaptobenzimidazole, 2-mercaptobenzthiazole, 2-mercaptobenzoxazole, urazole, thiouracil, mercaptoimidazole, mercaptopyrimidine, and urea such as 1,1-dimethylurea and 1,3-dimethylurea, and Can include thiourea compounds. These adhesive aids are usually used in an amount of 10 parts by weight per 100 parts by weight of the alkali-soluble resin.
The amount is less than 5 parts by weight, preferably less than 5 parts by weight.

A spinner or coater is provided on a substrate (eg, a silicon / silicon dioxide coating, a glass substrate, a transparent substrate such as an ITO substrate, etc.) on which the above positive photoresist composition is used for the production of precision integrated circuit devices. After applying a suitable coating method such as pre-baking, exposing through a predetermined mask, and if necessary post-heating (PEB: Post Exposure
A good resist can be obtained by performing Bake), developing, rinsing and drying. Examples of the present invention will be shown below, but the present invention is not limited thereto.
In addition,% indicates weight% unless otherwise specified.

[0061]

【Example】

(1) Synthesis of novolac resin (a-1) m-cresol 129.77 g, p-cresol 32.
44 g, 2,5-xylenol 48.87 g and p-cyclohexylphenol (compound number [2-
a]) 17.63 g and formalin aqueous solution (37.27
%) 145.03 g was charged into a 1-liter three-necked flask 9
0.75 g of oxalic acid was added with stirring at 0 ° C. After 1 hour, the bath temperature was raised to 115 ° C., and the mixture was further stirred for 3 hours. Then replace the reflux condenser with a Liebig condenser,
Gradually raise the bath temperature to 200 ℃, unreacted formalin,
The water was removed. After distilling off at atmospheric pressure for 2 hours, gradually move to 1 m
The pressure was reduced to mHg to remove unreacted monomers and the like. The molten alkali-soluble novolac resin was returned to room temperature and recovered. The obtained novolak resin a-1 had a weight average molecular weight of 4120 (in terms of polystyrene) and a dispersity of 3.
It was 71.

(2) Synthesis of novolac resin (b-1)-
(L-1) In the same manner as in the above (1), the monomers shown in Tables 1 and 2 and a cyclohexylphenol compound (the parentheses in the table correspond to the compound numbers in the description) were charged in a predetermined mol%,
Novolak resins (b-1) to (l-1) were obtained by condensing with formaldehyde. In addition, (X) in Table 1 represents bisphenol A.

Table 1: Synthesis of novolac resin (mol% charged) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Novolac m-cresol p-cresol 2,5-xylenol cyclohexyl compound Mw ──────────────────────────────────── a-1 60 15 20 2-a 5 4120 b-1 60 5 5 2-a 30 3280 c-1 70 0 15 2-a 15 4300 d-1 70 20 0 2-c 10 5930 e-1 60 15 20 2-c 5 4730 f-1 60 15 20 2-g 5 7480 ─────────────────────────────────── -G-1 60 40 0--5150 h-1 60 15 20 (X) 5 4370 i-1 60 20 0 - - 4470 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Table 2: Synthesis of novolac resin (mol% charged) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Novolac m-cresol p-cresol quinolenol or cyclohexyl Mw trimethylphenol compound ──────────────────────────────────── j-1 60 15 3,5-xylenol 20 2-c 5 4120 k-1 60 15 2,3,5-trimethylphenol 20 2-a 5 4760 l-1 70 0 2,3,5-trimethylphenol 20 2 -C 10 5020 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

(3) Separation Novolak resin (a-2)
(L-2) The novolac resin (a- obtained in the above (1) and (2)
100 g of each of 1) to (l-1) is dissolved in 1000 g of acetone, and 1000 g to 160 g of n-hexane is stirred.
0 g was added, and the mixture was stirred for 30 minutes and left standing for 1 hour. After removing the upper layer by decantation, the solvent was distilled off from the remaining lower layer using a rotary evaporator to obtain solid novolaks (a-2) to (1-2).

Table 3: Separation novolak resin ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Novolak low molecular weight component removal rate (%) Mw ─────────────────────────────────── a-2 57 7410 b-2 61 6590 c -2 63 7890 d-2 36 9920 e-2 54 8470 f-2 41 11260 g-2 63 11090 h-2 54 7710 i-2 50 8710 j-2 46 7060 k-2 48 8620 1-2 -51 9360- ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

(4) Synthesis of Photosensitive Material (A-1) Compound (5) 38.9 g, 1,2-naphthoquinonediazide-5-sulfonyl chloride 53.7 g, acetone 80
0 ml was charged into a three-necked flask and uniformly dissolved. Then, 20.8 g of N-methylpiperidine was gradually added dropwise, and the mixture was reacted at 25 ° C for 3 hours. The reaction mixture was poured into 3 l of a 1% hydrochloric acid aqueous solution, the precipitate formed was filtered off, washed with water and dried to obtain 76.8 g of a photosensitive material (A-1).

(5) Synthesis of Photosensitive Material (B-1) Compound (15) 53.7 g, 1,2-naphthoquinonediazide-5-sulfonyl chloride 53.7 g, acetone 8
00 ml was charged into a three-necked flask and uniformly dissolved.
Then, 21.2 g of triethylamine was gradually added dropwise,
The reaction was carried out at 25 ° C for 3 hours. The reaction mixture was poured into 3 l of a 1% hydrochloric acid aqueous solution, the resulting precipitate was filtered off, washed with water and dried to obtain 90.2 g of a photosensitive material (B-1).

(6) Synthesis of Photosensitive Material (C-1) α, α ', α "-tris (4-hydroxyphenyl) -1-
Ethyl-4-isopropylbenzene 35.3 g, 1,2
-Naphthoquinonediazide-5-sulfonyl chloride 5
3.7 g and 800 ml of acetone were charged into a three-necked flask and uniformly dissolved. Then triethylamine 21.
2 g was gradually added dropwise and reacted at 25 ° C. for 3 hours. The reaction mixture was poured into 3 l of a 1% hydrochloric acid aqueous solution, the resulting precipitate was filtered off, washed with water and dried to obtain 75.0 g of a photosensitive material (C-1).

(7) Synthesis of Photosensitive Material (D-1) 2,3,4,4'-Tetrahydroxybenzophenone 19.19
g, 1,2-naphthoquinonediazide-5-sulfonyl chloride 53.7 g and acetone 800 ml were charged into a three-necked flask and uniformly dissolved. Then, 21.2 g of triethylamine was gradually added dropwise and reacted at 25 ° C. for 3 hours. The reaction mixture was poured into 3 l of a 1% hydrochloric acid aqueous solution, the precipitate formed was filtered off, washed with water and dried to give Photosensitive Material (D-1) 6
2.3 g was obtained.

(8) Preparation and Evaluation of Positive Photoresist Composition Novolak resin (a-) obtained in the above (1) to (3)
1) to (l-1) and (a-2) to (l-2), and photosensitive materials (A-1) to (D-) obtained in (4) to (7) above.
1), a solvent and, if necessary, a polyhydroxy compound are mixed at a ratio shown in Table 4 to obtain a uniform solution, and then a pore size of 0.1
A photoresist composition was prepared by filtering using a 0 μm microfilter. This photoresist composition,
A silicon wafer was coated with a spinner and dried at 90 ° C. for 60 seconds on a vacuum adsorption type hot plate to obtain a resist film. This film was exposed using a reduction projection exposure device (reduction projection exposure device NSR-2005i9C manufactured by Nikon Corporation), PEB was performed at 110 ° C. for 60 seconds, and the film was developed with a 2.38% tetramethylammonium hydroxide aqueous solution for 1 minute. It was washed with water for 30 seconds and dried. The resist pattern of the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the resist. The results are shown in Table 5. The sensitivity was defined as the reciprocal of the exposure dose for reproducing a mask pattern of 0.60 μm, and shown as a relative value to the sensitivity of the resist of Comparative Example 1. Resolution is 0.60 μm
Represents the limiting resolution at the exposure dose for reproducing the mask pattern of. The heat resistance was a temperature at which a resist-patterned silicon wafer was baked on a hot plate for 4 minutes and the deformation of the pattern did not occur. The shape of the resist is represented by the angle (θ) formed by the resist wall surface and the plane of the silicon wafer in the resist pattern cross section of 0.50 μm. The scum is indicated by the degree of development residue remaining in the resist pattern of 0.50 μm. The case where no residue is observed is indicated by ◯, the case where some residue is observed is indicated by Δ, and the portion which remains considerably is indicated by x.

[0072]

[Table 1]

Here, * 1 P-1: α, α, α'-tris (4-human oxyphenyl) -1-ethyl-4-isoprophylbenzene Zene P-2: tris (4-human oxyphenyl) methane P-3 : 1,1-Bis (4-human oxyphenyl) cyclohexane * 2 S-1: Ethyl cellosolve acetate S-2: 2-Hethyl ethyl hydroxypropionate S-3: 3-Methyl methoxypropionate S-4: 3-Ethoxypropionate Represents ethyl acid.

[0074]

[Table 2]

[0075]

The positive photoresist using the alkali-soluble novolac resin of the present invention is excellent in resist performance such as sensitivity, resolution, pattern profile, scum and heat resistance.

Claims (4)

[Claims] 1. An alkali-soluble novolac resin and 1,2
In a positive photoresist composition containing a quinonediazide compound, the alkali-soluble novolak resin is at least one of phenols represented by the following general formula [1] and at least a compound represented by the general formula [2]. A positive photoresist composition comprising a novolak resin obtained by condensing a mixture containing one kind with an aldehyde. [Chemical 1] Here, R _{1 to} R _3, which may be the same or different, are a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an aryl group, an aralkyl group, an alkoxycarbonyl group or an arylcarbonyl group, R ₄ to R ₅ may be the same or different and represents a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkenyl group, an aryl group or an aralkyl group. 2. The phenol according to claim 1, wherein
A positive photoresist composition comprising at least one selected from the group consisting of phenol, cresol, xylenol and trimethylphenol. 3. The phenol according to claim 1, wherein the phenol is
A positive photoresist composition, which is a mixture of m-cresol, p-cresol and 2,5-xylenol. 4. The phenol according to claim 1, wherein the phenol is
A compound of m-cresol, p-cresol and 2,5-xylenol, wherein the compound represented by the general formula [2] is at least one compound represented by the following general formulas [3] and [4]. And a positive photoresist composition. [Chemical 2]