JP3501432B2 - Positive photoresist composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention contains an alkali-soluble resin and a specific 1,2-quinonediazide compound, and emits radiation such as ultraviolet rays, far ultraviolet rays, X-rays, electron beams, molecular beams, γ-rays and synchrotron radiation. More specifically, the present invention relates to a positive photoresist composition that is sensitive to, and more specifically, a positive photoresist composition for microfabrication that provides high sensitivity and high resolution regardless of film thickness variation and that has a good development latitude. It is about things.

The positive photoresist composition of the present invention is applied to a substrate such as a semiconductor wafer, glass, ceramics or metal by spin coating or roller coating to a thickness of 0.5 to 2 μm. After that, it is heated and dried, and a circuit pattern or the like is baked through an exposure mask by irradiation of ultraviolet rays or the like, and if necessary, post-exposure baking is performed and then development is performed to form a positive image.

Further, patterning can be performed on the substrate by etching using this positive image as a mask. Typical fields of application include manufacturing processes for semiconductors such as ICs, manufacturing circuit boards such as liquid crystals and thermal heads, and other photo-ablation processes.

[0004]

2. Description of the Related Art As a positive photoresist composition,
Generally, a composition containing an alkali-soluble resin binder such as novolac and a naphthoquinonediazide compound as a photosensitive material is used. Novolac resin as a binder,
It is particularly useful for this application because it can be dissolved in an alkaline aqueous solution without swelling, and when it is used as a mask for etching, it gives a high resistance to plasma etching. 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 type photosensitive material have been developed and put into practical use. In particular, the progress of resist materials toward high resolution is remarkable, and sufficient results have been achieved in line width processing down to submicrons.

Conventionally, in order to enhance the resolution and obtain an image having a good pattern shape, it has been advantageous to use a resist having a high contrast (γ value), and technical development of a resist composition suitable for such a purpose has been conducted. I've been told. There are numerous publications disclosing such techniques. In particular, with respect to the novolak resin, which is the main part of the positive photoresist, many patent applications have been made regarding its monomer composition, molecular weight distribution, synthetic method, etc., and some results have been achieved. Also, with regard to the photosensitive material which is another main component, compounds having many structures which are effective for increasing the contrast have been disclosed. By designing a positive photoresist using these techniques, it has become possible to develop an ultrahigh resolution resist capable of resolving a pattern having a size comparable to the wavelength of light.

However, integrated circuits are becoming more and more integrated, and it is necessary to process an ultrafine pattern having a line width of 0.5 μm or less in the manufacture of a semiconductor substrate such as a VLSI. Is becoming. In such applications, particularly stable and high resolution is obtained,
There is a demand for a photoresist having a wide development latitude in order to always secure a constant processing line width. Further, it is required that no resist residue is generated in the resist pattern after development in order to prevent circuit processing defects.

Further, particularly in the formation of an ultrafine pattern of 0.5 μm or less, for example, even if a certain resolution is obtained with a certain coating thickness, it can be obtained by slightly changing the coating thickness. Phenomenon that resolution deteriorates (hereinafter,
It is known that there is "film thickness dependency"). Surprisingly, the resolving power changes greatly even if the film thickness changes by only a few hundredths of μm, and more or less than any of the typical positive photoresists currently on the market. I also found that there was a tendency. Specifically, when the thickness of the resist film before exposure changes within a range of λ / 4n (λ is the exposure wavelength, n is the refractive index of the resist film at that wavelength) with respect to the predetermined film thickness, The resolution that is applied varies.

The problem of the film thickness dependence is, for example, SPIE P
Its existence was pointed out in roceedings 1925, p. 626 (1993), and it is stated that this is caused by the multiple reflection effect of light in the resist film.

In particular, it has been found that when the contrast of the resist is increased so as to obtain a pattern having a high resolution and a rectangular cross section, the film thickness dependence is often increased. When actually processing a semiconductor substrate, a pattern is formed by using a resist film applied with a film thickness slightly different depending on the location due to the unevenness on the substrate surface or the unevenness of the coating film thickness. Therefore, this film thickness dependence has been one obstacle in carrying out fine processing close to the limit of its resolution using a positive photoresist.

To date, a large number of 1,2-naphthoquinonediazide compounds, which are polyhydroxy compounds having a specific structure, have been proposed in order to enhance the resolution. For example,
JP-A-57-63526, 60-163043, and 6
2-10645, 62-2, 10646, 62-150.
245, 63-220139, 64-76047,
JP-A-1-189644, 2-285351, 2-
296248, 2-296249, 3-4824
9, Same 3-48250, Same 3-158856, Same 3-2
28057, Japanese Patent Publication No. 4-502519, US Patent 495.
7846, 4992356, 5151340, 5
178986, European Patent 530148, etc. However, even if these photosensitive materials are used, they are insufficient from the viewpoint of reducing the film thickness dependency.

On the other hand, by using a photosensitive material having a hydroxyl group in the molecule, a resist having high contrast and high resolution can be obtained, for example, as described in JP-B-37-18.
015, JP-A-58-150948, JP-A-2-198.
46, ibid. 2-103543, ibid. 3-228057, ibid. 5
-323597, 6-148878, 6-1678
05, 6-202321, 7-104465, 7
-152152, 7-159990, U.S. Pat. No. 306.
1430, 3130047, 3130048, 3
130049, 3102809, 3184310,
3188210, 3180733, West German Patent 938
233, SPIE Proceedings Vol. 631, page 210, Vol. 1672, 23
1 (1992), 1672, 262 (1992) and 1925
See page 227 (1993).

However, the photosensitizers having a hydroxyl group in the molecule described above do not sufficiently satisfy the further increasing demands associated with high integration of semiconductors.

[0014]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a good positive photoresist composition having high sensitivity, high resolution, excellent film thickness dependence of resolution and development latitude. In the present invention, “film thickness dependency” means that the resist film thickness before exposure is λ / 4n as described above.
Is a variation in the resolving power of the resist obtained by exposure and (if necessary, baking) development when it changes in the range.

[0015]

Means for Solving the Problems As a result of paying attention to the above various characteristics, the present inventors have found that the above object can be achieved by using an alkali-soluble resin and a quinonediazide compound having a specific structural formula, The present invention has been completed based on this finding. That is, the gist of the present invention is as follows: (1) 1,2-quinonediazide-5- (and / or a polyhydroxy compound represented by the following general formula [I]
Or -4-) A positive photoresist composition containing at least one sulfonic acid ester and an alkali-soluble resin.

[0016]

[Chemical 3]

Here, R _{1 to} R ₆ : hydrogen atom, halogen atom, alkyl group, alkoxy group, alkenyl group or cycloalkyl group, which may be the same or different, R _{7 to} R ₉ : same or different good hydrogen atom or an alkyl group, R ₁₀ ~R _11: a hydrogen atom or an alkyl group, R _12: a hydrogen atom or an alkyl group, m = 0 or 1, n = 0 an integer, m + n ≧ 1, X 1 ~X ₃ : represents a group represented by the following general formula [II] or a hydrogen atom, provided that at least one of X _{1 to} X ₃ is a group represented by the general formula [II].

[0018]

[Chemical 4]

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The positive photoresist composition of the present invention is 1) linear, 2) has one hydroxyl group on each aromatic ring, and 3) has three linking groups on the aromatic ring. By using a polyhydroxy compound having a specific structure having a hydrophilic substituent represented by the general formula [II] in at least one of them, the above-mentioned specific effect can be exhibited. On the other hand, as compounds similar to the photosensitive material of the present invention, for example, the following polyhydroxy compounds [III] and [IV] are disclosed in JP-A Nos.
No. 159990.

[0020]

[Chemical 5]

However, the polyhydroxy compound having the above-mentioned specific structure used in the present invention is not disclosed.
Further, when the above-mentioned polyhydroxy compounds [III] and [IV] are used, sensitivity and film thickness dependency are particularly poor, and a positive photoresist which is practically satisfactory cannot be obtained.

The present invention will be described in detail below. In the above general formula [I], the alkyl group represented by R _{1 to} R ₆ includes a methyl group, an ethyl group, a propyl group, an isopropyl group, and n-.
Butyl group, isobutyl group, sec-butyl group, tert
An alkyl group having 1 to 4 carbon atoms such as a butyl group, more preferably a methyl group, an ethyl group, a propyl group,
It is an isopropyl group, and particularly preferably a methyl group or an ethyl group. Examples of the alkoxy group of R _{1 to} R ₆ include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group,
An n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group are preferable, more preferably a methoxy group and an ethoxy group, and particularly preferably a methoxy group. The alkenyl group represented by R _{1 to} R ₆ is preferably a vinyl group, a propenyl group or an allyl group, particularly preferably an allyl group. As the halogen atom of R _{1 to} R ₆ ,
A chlorine atom, a bromine atom and an iodine atom are preferable, and a chlorine atom is particularly preferable. The cycloalkyl group represented by R _{1 to} R ₆ is preferably a cyclopentyl group or a cyclohexyl group, more preferably a cyclohexyl group. Further, in the general formula [I], the alkyl group represented by R _{7 to} R ₉ is
The same alkyl group as the alkyl groups of R _{1 to} R ₆ can be mentioned. Further, as the alkyl group for R ₁₀ and R ₁₁ ,
Examples thereof include a methyl group, an ethyl group, a propyl group and an isopropyl group, with a methyl group being particularly preferred, and R ₁₂
Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and the like, but from the viewpoint of sensitivity, a particularly preferable one is A methyl group and an ethyl group. In the general formula [I], m is 0 or 1, n is an integer of 0 to 10, preferably 0 to 3, and m + n ≧ 1.

Specific preferred examples of the respective substituents of the above general formula [I] will be described below. R _{1 to} R ₃ are preferably a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an allyl group, a chlorine atom or a cyclohexyl group. More preferably, it is a hydrogen atom or a methyl group. R ₄ is preferably a hydrogen atom or a methyl group. R ₅ is preferably a hydrogen atom, a methyl group, an ethyl group or a chlorine atom. R ₆ is a methyl group, an ethyl group, a methoxy group, an allyl group, a chlorine atom,
A cyclohexyl group is preferred. R _{7 to} R ₉ are preferably a hydrogen atom, a methyl group or an ethyl group. Furthermore, X _{1 to} X ₃
At least one of is a group represented by the general formula [II],
X ₂ is particularly preferably a group represented by the general formula [II]. Furthermore, in the above general formula [I], the substitution positions of the aromatic hydroxyl groups at both ends are meta positions with respect to the linking group,
The para position is preferable, and the para position is more preferable.

Specific examples of the compound represented by the general formula [I] include the compounds represented by the following [I-1] to [I-36]. The compounds usable in the present invention are It is not limited to. These polyhydroxy compounds may be used alone or in admixture of two or more.

[0025]

[Chemical 6]

[0026]

[Chemical 7]

[0027]

[Chemical 8]

[0028]

[Chemical 9]

[0029]

[Chemical 10]

[0030]

[Chemical 11]

The photosensitizer of the present invention comprises, for example, an esterification reaction of the polyhydroxy compound represented by the general formula [I] with 1,2-naphthoquinonediazide-5- (and / or -4-) sulfonyl chloride. It is obtained by doing. That is, a predetermined amount of polyhydroxy compound and 1,2
-Naphthoquinonediazide-5- (and / or -4
-) Sulfonyl chloride as a solvent, for example, methyl isobutyl ketone, diglyme, ethyl acetate, acetonitrile, dichloroethane, dioxane, acetone, tetrahydrofuran, methyl ethyl ketone, N-methylpyrrolidone, chloroform, trichloroethane, trichloroethylene, dichloroethane or γ-butyl lactone. Etc. at least one kind is charged in a flask, and a basic catalyst such as sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, triethylamine, 4-dimethylaminopyridine, 4-methylmorpholine, N-methylpiperazine, N-methylpiperidine, etc. Is added dropwise to condense. The obtained product is crystallized in water, washed with water, and further purified and dried.

In the usual esterification reaction, a mixture having different esterification numbers and esterification positions can be obtained. However, by selecting the synthesis conditions or the structure of the polyhydroxy compound, only certain isomers can be selectively selected. It can also be synthesized. Hereinafter, the esterification rate in the present invention is defined as the average value of this mixture. This esterification rate is 1,2-naphthoquinonediazide-5 which is a raw material.
It can be controlled by the mixing ratio of-(and / or -4-) sulfonyl chloride and polyhydroxy compound. That is, since the added 1,2-naphthoquinonediazide-5- (and / or -4-) sulfonyl chloride undergoes an esterification reaction substantially all, in order to obtain a mixture having a desired esterification rate, It suffices to adjust the charged molar ratio of. The preferred esterification rate is 25 to 75%, more preferably 30 to 70%.

A molar ratio of 1,2-naphthoquinonediazide-5- (and / or -4-) sulfonyl chloride to the polyhydroxy compound [1,2-naphthoquinonediazide / polyhydroxy represented by the general formula [I]. Compound] is preferably 1.0 to 3.0. A more preferable range is 1.2 to 2.8. When the molar ratio is within this range, a certain amount of the polyhydroxy compound remains, exhibiting a good effect for the purpose of the present invention. This charge molar ratio is
When it is lower than this range, remarkable film slippage in the unexposed area is observed, and conversely, when it is high, the storage stability is deteriorated and the effects of the present invention are not exhibited.

In the present invention, the 1,2-naphthoquinone diazide-5-sulfonic acid ester and 1,2
-Naphthoquinonediazide-4-sulfonic acid ester can also be used in combination. Moreover, the reaction temperature in the said method is -20-60 degreeC normally, Preferably it is 0-40 degreeC.

The photosensitive material synthesized in this manner is used alone or in the photoresist composition of the present invention.
It is used by mixing one or more species and blending it with an alkali-soluble resin. The blending amount thereof is 5 to 150 parts by weight, preferably 20 to 100 parts by weight, relative to 100 parts by weight of the alkali-soluble resin (usually novolak resin). If this usage ratio is less than 5 parts by weight, the residual film rate is significantly reduced, and
If it exceeds 0 parts by weight, the sensitivity and the solubility in a solvent decrease.

In the present invention, the above-mentioned photosensitive material is used. If necessary, the following polyhydroxy compound and 1,2-naphthoquinonediazide-5- (and / or-
4-) An esterified product with sulfonyl chloride can be used in combination. At this time, the ratio of the naphthoquinone diazide ester photosensitive material of these polyhydroxy compounds to the photosensitive material in the present invention is 20/80 to 80/20 (weight ratio).
Is preferable. That is, if the photosensitive material of the present invention is less than 20% by weight of the total photosensitive material, the effect of the present invention cannot be sufficiently exhibited.

Examples of the polyhydroxy compounds include 2,3,4-trihydroxybenzophenone, 2,4
4'-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,4,6 3 ',
4 ', 5'-hexahydroxybenzophenone, 2,
Polyhydroxybenzophenones such as 3,4,3 ′, 4 ′, 5′-hexahydroxybenzophenone, 2,3,3
Polyhydroxyphenyl alkyl ketones such as 4-trihydroxyacetophenone and 2,3,4-trihydroxyphenylhexyl ketone, bis (2,4-dihydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane , Bis ((poly) hydroxyphenyl) alkanes such as bis (2,4-dihydroxyphenyl) propane-1, propyl 3,4,5-trihydroxybenzoate, phenyl 3,4,5-trihydroxybenzoate, etc. Polyhydroxybenzoates, bis (2,3,4-trihydroxybenzoyl) methane, bis (2,3,4-trihydroxybenzoyl) benzene and other bis (polyhydroxybenzoyl) alkanes or bis (polyhydroxybenzoyl) ) Aryls, ethylene glycol-di (3,3 - dihydroxybenzoate)
Alkylene-di (polyhydroxybenzoate) such as
, 3,5,3 ', 5'-biphenyl tetrol, 2,
4,2 ', 4'-biphenyl tetrol, 2,4,6
3 ', 5'-biphenylbentol, 2,4,6
Polyhydroxybiphenyls such as 2 ′, 4 ′, 6′-biphenylhexol,

4,4 ', 4 "-trihydroxy-3,
5,3 ', 5'-tetramethyltriphenylmethane,
4,4 ', 4 "-trihydroxy-3" -methoxy-
3,5,3 ', 5'-tetramethyltriphenylmethane, 4,4', 2 "-trihydroxy-3,5,3 ',
5'-tetramethyltriphenylmethane, 4,4 ',
2 "-trihydroxy-2,2'-dimethyl-5,5 '
-Dicyclohexyltriphenylmethane, 4,4 ',
2 "-trihydroxy-2,5,2 ', 5'-tetramethyltriphenylmethane, 4,4', 3", 4 "-tetrahydroxy-3,5,3 ', 5'-tetramethyltriphenyl Methane, 4,4 ', 2 ", 3", 4 "-pentahydroxy-3,5,3', 5'-tetramethyltriphenylmethane, 2,3,4,2 ', 3', 4 ', 3 ″,
Polyhydroxytriphenylmethanes such as 4 ″ -octahydroxy-5,5′-diacetyltriphenylmethane, 3,3,3 ′, 3′-tetramethyl-1,1′-spirobi-indane-5,6,6. 5 ', 6'-tetrol,
3,3,3 ', 3'-Tetramethyl-1,1'-spirobi-indan-5,6,7,5', 6 ', 7'-hexool, 3,3,3', 3'-tetra Methyl-1,1 '
-Spirobiindane-4,5,6,4 ', 5', 6'-
Hexool, 3,3,3 ', 3'-tetramethyl-
1,1'-spirobi-indane-4,5,6,5 ',
Polyhydroxyspirobi-indanes such as 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], 2- (3,4-
Dihydroxyphenyl) -3,5,7-trihydroxybenzopyran, 2- (3,4,5-trihydroxyphenyl) -3,5,7-trihydroxybenzopyran, 2
-(3,4-dihydroxyphenyl) -3- (3,4,
5-trihydroxybenzoyloxy) -5,7-dihydroxybenzopyran, 2- (3,4,5-trihydroxyphenyl) -3- (3,4,5-trihydroxybenzoyloxy) -5,7-dihydroxy Polyhydroxybenzopyrans such as benzopyran, 2,4,4-trimethyl-2- (2 ', 4'-dihydroxyphenyl)
-7-hydroxychroman, 2,4,4-trimethyl-
2- (2 ', 3', 4'-trihydroxyphenyl)-
Polyhydroxyphenyl chromanes such as 7,8-dihydroxychroman, 2,4,4-trimethyl-2- (2 ', 4', 6'-trihydroxyphenyl) -5,7-dihydroxychroman, 2,6- Screw (2,3,4-
Trihydroxybenzyl) -4-methylphenol,
2,6-bis (2,4-dihydroxybenzyl) -4-
Methylphenol, 2,6-bis (5-chloro-2,4
-Dihydroxybenzyl) -4-methylphenol,
2,6-bis (2,4,6-trihydroxybenzyl)
-4-Methylphenol, 2,6-bis (2-acetyl-3,4,5-trihydroxybenzyl) -4-methylphenol, 2,4,6-tris (2,3,4-trihydroxybenzyl) Phenol, 2,6-bis (3,5
-Dimethyl-4-hydroxybenzyl) -4-methylphenol, 2,6-bis (2,5-dimethyl-4-hydroxybenzyl) -4-methylphenol, 2,6-bis (2,5-dimethyl-4) -Hydroxybenzyl) -4
-Phenylphenol, 2,6-bis (2,5-dimethyl-4-hydroxybenzyl) -4-cyclohexylphenol, 2,6-bis (4-hydroxybenzyl)-
4-cyclohexylphenol, 2,6-bis {3'-
(4 "-hydroxybenzyl) -4'-hydroxy-
5'-methylbenzyl} -4-cyclohexylphenol, 2,6-bis {3 '-(3 "-methyl-4" -hydroxybenzyl) -4'-hydroxy-5'-methylbenzyl} -4-cyclohexylphenol , 2, 4, 6
-Tris (3,5-dimethyl-4-hydroxybenzyl) -phenol, 4,6-bis (3,5-dimethyl-
4-hydroxybenzyl) pyrogallol, 2,6-bis (3-methyl-4-hydroxybenzyl) -4-methylphenol, 2,6-bis (3,5-dimethyl-4-hydroxybenzyl) phloroglucinol, etc. Hydroxybenzylphenols,

2,2'-dihydroxy-5,5'-bis (4 "-hydroxybenzyl) biphenol, 2,2 '
-Dihydroxy-3,3'-dimethoxy-5,5'-bis (4 "-hydroxybenzyl) biphenol, 2,
2'-dihydroxy-3,3'-dimethoxy-5,5 '
-Bis (3 ", 5" -dimethyl-4 "-hydroxybenzyl) biphenol, 2,2'-dihydroxy-3,
3'-dimethoxy-5,5'-bis (3 "-methyl-
4 "-hydroxybenzyl) biphenol, 4,4'-
Dihydroxy-3,3'-dimethyl-5,5'-bis (3 ", 5" -dimethyl-4 "-hydroxybenzyl)
Biphenols such as biphenols, 1,3,3,5-
Tetrakis (4-hydroxyphenyl) pentane, 1,
1-bis {3 '-(4 "-hydroxybenzyl) -4'
-Hydroxy-5'-methylphenyl} cyclohexane, 1,1-bis {3 '-(3 "-methyl-4" -hydroxybenzyl) -4'-hydroxy-5'-methylphenyl} cyclohexane, 1, 1-bis {3'-
(3 ", 6" -dimethyl-4 "-hydroxybenzyl)
-4'-hydroxy-5'-methylphenyl} cyclohexane, 4,4'-methylenebis {2- (4 "-hydroxybenzyl) -3,6-dimethylphenol}, 4,
4'-methylenebis {2- (3 "-methyl-4" -hydroxybenzyl) -3,6-dimethylphenol},
4,4'-methylenebis {2- (3 "-methyl-4"-
(Hydroxybenzyl) -3-cyclohexyl-6-methylphenol}, 4,4'-methylenebis {2-
(2 ", 4" -dihydroxybenzyl) -6-methylphenol}, 1,8-bis {3 '-(4 "-hydroxybenzyl) -4'-hydroxy-5'-methylphenyl} menthane, 1,8 -Bis {3 '-(3 "-methyl-
4 "-hydroxybenzyl) -4'-hydroxy-5 '
Hydroxyphenylalkanes such as -methylphenyl} menthane,

3,3'-bis (4 "-hydroxybenzyl) -4,4'-dihydroxy-5,5" -diallyldiphenyl ether, 3,3'-bis (4 "-hydroxybenzyl) -4 , 4'-dihydroxy-5,5 "-dimethyldiphenyl thioether, 3,3'-bis (3"-
Methyl-4 ″ -hydroxybenzyl) -4,4′-dihydroxy-5,5 ″ -dimethyldiphenylthioether, 3,3′-bis (3 ″, 6 ″ -dimethyl-4 ″ -hydroxybenzyl) -4,4 ′ -Dihydroxy-5,
5 "-dimethyldiphenyl thioether, 3,3'-bis (3" -methyl-4 "-hydroxybenzyl) -4,
Diphenyl ethers such as 4'-dihydroxy-5,5 "-diallyl diphenyl ether, 2,6-bis (4 '
-Hydroxybenzyl) -4-benzenesulfonamide-phenol, 2,6-bis (3 ', 6'-dimethyl-4'-hydroxybenzyl) -4-benzenesulfonamide-phenol and other sulfonamide phenols or quercetin, Flavono pigments such as rutin,
Furthermore, a low nucleolar form of novolac, or an analogue thereof can be used.

Further, a polymer containing an aromatic hydroxyl group such as acetone pyrogallol condensation resin or polyvinyl phenol can be used instead of these low molecular weight compounds. Further, it is possible to substitute the hydroxyl group of novolac itself with quinonediazide in an appropriate amount so that it also functions as a photosensitive material or as a binder.

Among these, in particular, a portion having one or more aromatic hydroxyl groups on the same aromatic ring is included, and a total of 3
Those having a structure having one or more hydroxyl groups are preferable.
In addition, 1,2-naphthoquinonediaside-5- (and / or-, which is a known aromatic or aliphatic polyhydroxy compound,
4-) Sulfonic acid ester compounds include, for example, JP-B-56-2333, JP-B-62-3411, JP-B-3-2293, JP-B-3-42656, JP-A-58-150948, and JP-A-58-150948. 60-154249
JP-A-60-134235, JP-A-62-10646, JP-A-62
-153950, JP-A-60-146234, JP-A-62-178562,
JP-A 63-113451, JP-A 64-76047, JP-A 1-14753
No. 8, JP-A 1-189644, JP-A 1-309052, JP-A 2-
19846, JP2-84650, JP2-72363, JP2
-103543, JP-A-2-285351, JP-A-2-296248, JP-A-2-296249, JP-A-3-48251, JP-A-3-48249,
JP-A-3-119358, JP-A-3-144454, JP-A-3-185447
No. 4-1652, No. 4-60548, No. 5-15823
No. 4, JP-A-5-224410, JP-A No. 5-303198, JP-A No. 5-2
97580, Japanese Unexamined Patent Publication No. 5-323597, Japanese Patent Application No. 5-251781, Japanese Patent Application No. 5-251780, Japanese Patent Application No. 5-233537, U.S. Pat.No. 4,797,34
No. 5, No. 4,957,846, No. 4,992,356, No. 5,151,340,
Examples thereof include compounds described in JP-A-5,178,986, European Patent Nos. 530,148 and 573,056.

Examples of the alkali-soluble resin used in the present invention include novolac resin, acetone-pyrogallol resin, polyhydroxystyrene and derivatives thereof. Among these, novolac resin is particularly preferable,
It can be obtained by addition-condensing an aldehyde with a predetermined monomer as a main component in the presence of an acidic catalyst.

As the predetermined monomer, phenol, m
-Cresol, p-cresol, o-cresol and other cresols, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol, 2,3-xylenol and other xylenols, m-ethylphenol, p- Alkylphenols such as ethylphenol, o-ethylphenol, pt-butylphenol, trialkylphenols such as 2,3,5-trimethylphenol, 2,3,4-trimethylphenol, p-methoxyphenol, m-methoxyphenol , 3,5-dimethoxyphenol, 2-methoxy-4-methylphenol, m-ethoxyphenol, p-ethoxyphenol, m-propoxyphenol, p-propoxyphenol, m-butoxyphenol, p-butoxyphenol, and other alkoxyphenols. Kind Bisalkylphenols such as 2-methyl-4-isopropylphenol, m-chlorophenol, p-chlorophenol, o-chlorophenol, dihydroxybiphenyl, bisphenol A, phenylphenol, resorcinol, naphthol and other hydroxyaromatic compounds alone or Two or more kinds can be mixed and used, but not limited thereto.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde. , O-chlorobenzaldehyde,
m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-
Methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, furfural,
Chloroacetaldehyde and acetals thereof such as chloroacetaldehyde diethyl acetal can be used, and of these, formaldehyde is preferably used.

These aldehydes may be used alone or in combination of two or more. As the acidic catalyst, hydrochloric acid, sulfuric acid, formic acid, acetic acid, oxalic acid or the like can be used.

Further, JP-A-60-45238 and 60-
97347, 60-140235, 60-1897.
39, 64-14229, JP-A-1-276131,
2-60915, 2-275955, 2-282
745, 4-101147, 4-122938, etc., that is, it is preferable to use a technique in which low-molecular components of novolac resin are removed or reduced.

The novolak resin thus obtained preferably has a weight average molecular weight in the range of 1,500 to 25,000. If it is less than 1500, the film loss of the unexposed portion after development is large, and if it exceeds 25,000, the developing speed becomes small. Here, the weight average molecular weight is defined by the polystyrene conversion value of gel permeation chromatography.

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 5.0. If the dispersity exceeds 7, the effect of the present invention cannot be obtained. When the dispersity is less than 1.5, a high-level purification step is required for synthesizing the novolac resin, which is unsuitable for practical use.

The weight average molecular weight and dispersity of the novolak resin can be appropriately set depending on the kind of the novolac resin.

The alkali-soluble resin is a novolak resin synthesized by a condensation reaction between a mixture containing two or more kinds of phenol, cresol, xylenol and trimethylphenol (however, m-cresol is essential) and an aldehyde compound. In this case, the weight average molecular weight is 5500.
It is preferably ˜25,000, more preferably 6
000 to 25,000. Furthermore, the above novolak resin has a ratio of the weight average molecular weight to the number average molecular weight of 1.5 to 5.
It is preferably 0.

The alkali-soluble resin is p-cresol, o-cresol, 2,3-xylenol, 2,6-
In the case of at least one type of novolak resin synthesized by a condensation reaction of a mixture containing at least four types of xylenol and trimethylphenol (o-cresol is essential) and an aldehyde compound, a weight average molecular weight and a number average molecular weight. Is preferably 1.5 to 5.0 and the weight average molecular weight is 1500 to 6000.

As described above, the effect of the present invention becomes more remarkable by setting the weight average molecular weight and the polydispersity within predetermined ranges depending on the type of novolak resin used.

The low molecular weight compound having a phenolic hydroxyl group (water-insoluble alkali-soluble low molecular weight compound) that can be used in the present invention will be described.

The development latitude can be improved by adding a water-insoluble alkali-soluble low molecule to the composition of the present invention in order to accelerate the dissolution in a developing solution. Specific examples of the water-insoluble alkali-soluble low molecule include polyhydroxy compounds. Preferred polyhydroxy compounds are 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′-biphenyltetrol, 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 ', Examples include α′-tetrakis (4-hydroxyphenyl)]-xylene.

Among these, as the water-insoluble alkali-soluble low-molecular weight compound, the total number of carbon atoms in one molecule is 60 or less, and the water-insoluble alkali-soluble low-molecular weight compound having 2 to 8 phenolic hydroxyl groups in one molecule is used. Compounds are preferred. Furthermore, the water-insoluble alkali-soluble low molecular weight compound has a ratio of phenolic hydroxyl groups to aromatic rings of 0.5 to 1.
4 and the total number of carbon atoms in one molecule is 12 to 60, and at least one water-insoluble alkali-soluble low-molecular compound having 2 to 10 phenolic hydroxyl groups in one molecule is preferable. . Among such compounds, compounds that increase the rate of alkali dissolution of the alkali-soluble resin when added to the water-insoluble alkali-soluble resin are particularly preferable. As a result, the development latitude is further improved.

If the compound has more than 60 carbon atoms, the effect of the present invention is reduced. On the other hand, if it is less than 12, a new defect such as a decrease in heat resistance occurs.
In order to exert the effect of the present invention, it is necessary to have at least two hydroxyl groups in the molecule, but if it exceeds 10, the effect of improving the development latitude is lost. Also, the ratio of phenolic hydroxyl group to aromatic ring is 0.5.
If it is less than 1, there is a large dependency on the film thickness, and the development latitude tends to be narrowed. If this ratio exceeds 1.4, the stability of the composition deteriorates, and it becomes difficult to obtain high resolution and good film thickness dependency, which is not preferable.

The low molecular weight compound is preferably added in an amount of 1 to 100% by weight, more preferably 2 to 80% by weight, based on the alkali-soluble resin. If the amount added exceeds 100% by weight, the development residue deteriorates and a new defect that the pattern is deformed during development is not preferable. Examples of the water-insoluble alkali-soluble low molecular weight compound having a phenolic hydroxyl group used in the present invention include those disclosed in JP-A-4-122938, JP-A-2-28531 and JP-A-2-2429.
73, 2-2-275995, 4-251849, 5
-303199, 5-22440, 6-30120
4 each gazette, U.S. Pat.
57, No. 5,318,875, European Patent No. 219294, etc., and can be easily synthesized by those skilled in the art.

As the solvent for dissolving the photosensitive material and the alkali-soluble resin of the present invention, 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, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate , Ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate,
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.

Furthermore, 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 (Shin-Akita Kasei Co., Ltd.)
Product), Megafasc F171, F173 (manufactured by Dainippon Ink Co., Ltd.), Florard FC430, FC431 (manufactured by Sumitomo 3M Ltd.), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, S
Fluorine-based surfactants such as C104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer K
P341 (manufactured by Shin-Etsu Chemical Co., Ltd.) or acrylic acid-based or methacrylic acid-based (co) polymerization polyflow No. 75,
No. 95 (manufactured by Kyoeisha Oil and Fat Chemical Co., Ltd.) and the like. Among these surfactants, fluorine-based surfactants and silicon-based surfactants are particularly preferable. The content of these surfactants is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the alkali-soluble resin and the quinonediazide compound in the composition of the present invention.

These surfactants may be added alone or in some combinations.

The developer of the positive photoresist composition of the present invention includes sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, inorganic alkalis such as aqueous ammonia, ethylamine,
Primary amines such as n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetra An aqueous solution of alkali such as methylammonium hydroxide, tetraethylammonium hydroxide, quaternary ammonium salt such as choline, cyclic amines such as pyrrole and piperidine, and the like can be used. 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.

Of these developers, quaternary ammonium salts are preferable, and tetramethylammonium hydroxide and choline are more preferable.

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
43, CIDisperse Blue 96, CIFluorescent Brighte
ning Agent 112, 135 and 163, CI Solvent Yellow 14,
16,33 and 56, CI Solvent Orange 2 and 45, CISolv
ent Red 1,3,8,23,24,25,27 and 49, CI Pigment Green
10, 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 adhesion aids are usually mixed 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 alkali-soluble resin.

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 specified mask, and post-baking (PEB: Post Exposure Bak)
A good resist can be obtained by performing e), 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.

[0072]

【Example】

Synthesis example (1) Synthesis of compound [I-1] 4 equipped with a stirrer, reflux condenser, thermometer, dropping device
2,5-xylenol 855 g, 1,
1,2-trimethoxyethane 84 g, ethanol 100
0 ml was charged. After adding 7 g of concentrated sulfuric acid to this mixture, the mixture was stirred under reflux conditions for 2 hours. The obtained reaction mixture was poured into 10 l of distilled water, and excess 2,5-xylenol was removed from the precipitated white solid by steam distillation to obtain a binuclear mixture A. This mixture A was purified by column chromatography to obtain 94 g of binuclear body B. To the same reactor, 56 g of the binuclear body B obtained above, 168 g of 50% dimethylamine aqueous solution and 200 ml of ethanol were charged, and 151 g of 37% formalin aqueous solution was added dropwise over 1 hour while stirring. After completion of dropping, the mixture was stirred under reflux conditions for 10 hours. After the reaction was completed, the precipitated white solid was filtered to obtain 64 g of an aminomethyl compound. A similar reaction apparatus was charged with 63 g of an aminomethyl derivative and 388 g of acetic anhydride, and the mixture was heated and stirred at 150 ° C. After stirring for 10 hours, excess acetic anhydride was distilled off under reduced pressure, the residue was dissolved in acetone and crystallized in 500 ml of distilled water, and the precipitated white solid was collected by filtration and washed with methanol to give acetoxy compound 7
0 g was obtained. Finally, 63 g of the acetoxy compound obtained above, 224 g of phenol, 250 ml of methanol, and concentrated sulfuric acid 1
2 g was charged, and the mixture was stirred under reflux conditions for 20 hours. After the reaction was completed, the obtained reaction mixture was poured into 5 l of distilled water, and the precipitated solid was washed with distilled water to obtain 55 g of the desired compound [I-1].

Synthesis Example (2) Synthesis of Compound [I-2] Using methoxy-2-propanone as a starting material instead of 1,1,2-trimethoxyethane in Synthesis Example (1), Synthesis Example (1) The target product [I-2] was obtained by the same operation.

Synthesis Example (3) Synthesis of Compound [I-3] Synthesis Example (1) using hydroxyacetone as a starting material instead of 1,1,2-trimethoxyethane in Synthesis Example (1)
The target product [I-3] was obtained by the same operation as.

Synthesis Example (4) Synthesis of Comparative Compound [III] 1,1,2-Trimethoxyethane and 2,2 of Synthesis Example (1)
Acetaldehyde and p-cresol were used as starting materials in place of 5-xylenol, and o-cresol was used in place of phenol in the final condensation reaction by the same operation as in Synthesis Example (1). Got

Synthesis Example (5) Synthesis of Comparative Compound [IV] 1,1,2-trimethoxyethane and 2, of Synthesis Example (1)
Acetone and o-cresol were used as starting materials in place of 5-xylenol, and p-cresol was used in place of phenol in the final condensation reaction, and the target compound [IV] was obtained by the same operation as in Synthesis Example (1). Got Synthesis example (6) Synthesis of photosensitive material a 51.2 g of compound [I-1] obtained in synthesis example (1), 1,
2-naphthoquinonediazide-5-sulfonyl chloride 5
3.7 g and 900 ml of acetone were charged into a three-necked flask and uniformly dissolved. Then N-methylpiperidine 2
0.8 g was gradually added dropwise and reacted at 25 ° C. for 3 hours.
The reaction mixture was poured into 3.2 l of a 1% aqueous hydrochloric acid solution, the precipitate formed was filtered off, washed with water and dried to give 1,2-naphthoquinonediazide-5-sulfonate of compound [I-1] (photosensitive). 92.5 g of the product a) was obtained.

Synthesis Example (7) Synthesis of Photosensitive Material b Compound [I-2] obtained in Synthesis Example (2) 52.7 g, 1,
2-naphthoquinonediazide-5-sulfonyl chloride 5
3.7 g and 900 ml of acetone were charged into a three-necked flask and uniformly dissolved. Then N-methylpiperidine 2
0.8 g was gradually added dropwise and reacted at 25 ° C. for 3 hours.
The reaction mixture was poured into 3.2 l of a 1% aqueous hydrochloric acid solution, the precipitate formed was filtered off, washed with water and dried to give 1,2-naphthoquinonediazide-5-sulfonate of compound [I-2] (photosensitive). The product b) 93.1g was obtained.

Synthesis Example (8) Synthesis of Photosensitive Material c Compound [I-3] obtained in Synthesis Example (3) 51.2 g, 1,
2-naphthoquinonediazide-5-sulfonyl chloride 5
3.7 g and 1000 ml of acetone were 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 3.2 l of a 1% aqueous hydrochloric acid solution, the precipitate formed was filtered off, washed with water and dried to give compound [I-
3] to obtain 91.8 g of 1,2-naphthoquinonediazide-5-sulfonic acid ester (photosensitive material c).

Synthesis Example (9) Synthesis of Photosensitive Material d 46.9 g of the comparative compound [III] obtained in Synthesis Example (4),
53.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 900 ml of acetone were 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 3.2 l of a 1% hydrochloric acid aqueous solution, the precipitate formed was filtered off, washed with water and dried to give compound [III].
1,2-naphthoquinonediazide-5-sulfonic acid ester (photosensitive material d) was obtained.

Synthesis Example (10) Synthesis of Photosensitive Material e Comparative compound [IV] obtained in Synthesis Example (5) 49.7 g,
53.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 900 ml of acetone were 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 3.2 l of a 1% aqueous hydrochloric acid solution, the precipitate formed was filtered off, washed with water and dried to give 1,2-naphthoquinonediazide-5-sulfonic acid ester of compound [IV] (photosensitive material e). ) 91.0g was obtained.

Synthesis Example (11) Synthesis of Novolac Resin A 50 g of m-cresol, 25 g of p-cresol, 2,5
-Xylenol 28 g, 37% formalin aqueous solution 53 g
Further, 0.15 g of oxalic acid was charged into a three-necked flask, the temperature was raised to 100 ° C. with stirring, and the reaction was carried out for 14 hours. Then, the temperature was raised to 200 ° C., and the pressure was gradually reduced to 1 mmHg, and water, unreacted monomers, formaldehyde, oxalic acid, etc. were distilled off. Next, the molten novolac resin was returned to room temperature and collected. The obtained novolak resin had a weight average molecular weight of 4,800 (in terms of polystyrene). Next, 20 g of this novolak resin was completely dissolved in 60 g of methanol, and then 30 g of water was gradually added thereto with stirring to precipitate the resin component. The upper layer was removed by decantation, the precipitated resin component was recovered, heated to 40 ° C., and dried under reduced pressure for 24 hours to obtain an alkali-soluble novolak resin A. The obtained novolak resin had a weight average molecular weight of 9960 (in terms of polystyrene) and a dispersity of 3.50. The contents of the monomer, dimer and trimer are 0%, 2.3% and 3.5%, respectively,
43% of low molecular weight components were removed by the fractional reprecipitation operation.

Synthesis Example (12) Synthesis of Novolac Resin B m-cresol 259.54 g, p-cresol 9.7
3 g, 2,3-xylenol 62.31 g, and formalin aqueous solution (37.17%) 218.14 g were stirred.
A 1-liter three-necked flask equipped with a reflux condenser and a thermometer was charged, and the mixture was stirred at 90 ° C. under an oxalic acid dihydrate.
13 g was added. After 30 minutes, raise the bath temperature to 130 ° C,
The contents were refluxed by further stirring for 3 hours and 30 minutes.
Then, the reflux condenser was replaced with a Liebig condenser, and the bath temperature was raised to 200 ° C. over about 1 hour to remove unreacted formalin, water and the like. After further distilling at atmospheric pressure for 1 hour, the pressure was gradually reduced to 1 mmHg to distill off unreacted monomers and the like. It took 2 hours to evaporate under reduced pressure.

The molten alkali-soluble novolac resin was returned to room temperature and recovered. The weight average molecular weight of the obtained novolak resin was 2290 (converted to polystyrene).
100 g of this novolak resin was dissolved in 1000 g of acetone, 1000 g of n-hexane was added with stirring, the mixture was further stirred at room temperature for 30 minutes, and then allowed to stand 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 novolac (a-
1) was obtained. The obtained novolac resin (B) has a weight average molecular weight of 5430 (in terms of polystyrene) and a dispersity of 2.
It was 4.

Synthesis Example (13) Synthesis of Novolac Resin C 30 g of p-cresol, 14 g of o-cresol, 2,3
-Dimethylphenol 50g, 2,3,5-trimethylphenol 20g, 2,6-dimethylphenol 4.9
g was mixed with 50 g of diethylene glycol monomethyl ether and equipped with a stirrer, a reflux condenser and a thermometer.
I put it in a one-necked flask. Next, 85 g of a 37% formalin aqueous solution was added, and the mixture was stirred while heating in an oil bath at 110 ° C. When the internal temperature reached 90 ° C, 6.3 g of oxalic acid 2
The hydrate was added. After that, the oil bath temperature is set to 130 for 18 hours.
The reaction was continued while maintaining the temperature at 0 ° C, then the reflux condenser was removed, and the mixture was distilled under reduced pressure at 200 ° C to remove the unreacted monomer.
The obtained novolak resin had an Mw of 3280 and a dispersity of 2.75.

Preparation and Evaluation of Positive Photoresist Compositions [Examples 1 to 5] Photosensitive Materials a to c obtained in Synthesis Examples (6) to (8) and Synthesis Examples (11) to (13) Novolak resins A to C obtained in 1., solvent ethyl 2-hydroxypropionate and polyhydroxy compound (p): α, α,
Ratio (weight) of α'-tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene shown in Table 1.
After mixing to form a uniform solution, the solution was filtered using a Teflon microfilter having a pore size of 0.10 μm to prepare a photoresist composition. This photoresist composition was applied onto a silicon wafer using a spinner while changing the rotation speed, and dried on a vacuum contact hot plate at 90 ° C. for 60 seconds to obtain resists having film thicknesses of 0.97 μm and 1.02 μm, respectively. A film was obtained.

This film was exposed by using a reduction projection exposure apparatus (reduction projection exposure apparatus NSR-2005i9C manufactured by Nikon Corporation), and then PEB was performed at 110 ° C. for 60 seconds to prepare a 1% solution of 2.38% tetramethylammonium hydroxide. It was developed for 1 minute, 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 2.

The sensitivity was defined as the reciprocal of the exposure dose for reproducing a mask pattern of 0.50 μm, and shown as a relative value to the sensitivity in Comparative Example 1 at a resist film thickness of 0.97 μm. The resolving power represents a limiting resolving power at an exposure amount for reproducing a mask pattern of 0.50 μm. The film thickness dependence was taken as an index of the film thickness dependence by the ratio of the resolution at a film thickness of 0.97 μm and the resolution at a film thickness of 1.02 μm. The closer this value is to 1.0, the smaller the film thickness dependence, and the more desirable the result. Development latitude is 0.97 μm
In the resist, the ratio of the sensitivity at the developing time of 40 seconds and the sensitivity at the developing time of 90 seconds was used as an index of the developing latitude. The closer this value is to 1.0, the wider the development latitude and the more desirable the result.

[Comparative Examples 1 to 5] Of the compounds used in Examples 1 to 5, instead of the photosensitive substances a to c, Synthesis Example (9),
The resist compositions shown in Table 1 were prepared and evaluated in the same manner as in Examples 1 to 5 except that the photosensitive materials d and e obtained in (10) were used. The results are also shown in Table 2.

[0089]

[Table 1]

[0090]

[Table 2]

[0091]

INDUSTRIAL APPLICABILITY The present invention uses a quinonediazide ester of a polyhydroxy compound having a specific structure to provide a positive photoresist composition having high sensitivity, high resolution, excellent film thickness dependence of resolution, and excellent development latitude. I will provide a.

─────────────────────────────────────────────────── --Continued from the front page (56) Reference JP-A-8-29978 (JP, A) JP-A-56-111852 (JP, A) JP-A-61-218616 (JP, A) JP-A-7- 152152 (JP, A) JP-A-6-167805 (JP, A) JP-A-7-168355 (JP, A) JP-A-7-159990 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03F ^7/ 004-7/18

Claims (4)

(57) [Claims] 1. At least one 1,2-quinonediazide-5- (and / or -4-) sulfonic acid ester of a polyhydroxy compound represented by the following general formula [I], and an alkali-soluble resin. A positive photoresist composition characterized by the following: [Chemical 1] Here, R _{1 to} R ₆ : hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, alkenyl groups or cycloalkyl groups, which may be the same or different, R _{7 to} R ₉ : hydrogen atoms, which may be the same or different. Or an alkyl group, R _{10 to} R ₁₁ :
Hydrogen atom or alkyl group, R ₁₂ : hydrogen atom or alkyl group, m = 0 or 1, n = 0 to 10 integer, m + n ≧ 1,
X _{1 to} X ₃ represent a group or a hydrogen atom represented by the following general formula [II], provided that at least one of X _{1 to} X ₃ is a group represented by the general formula [II]. [Chemical 2] 2. R _{10 to} R ₁₁ of the general formula [II] is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₁₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. The positive photoresist composition according to claim 1. 3. R _{10 to} R ₁₁ of the general formula [II] is a hydrogen atom or a methyl group, and R ₁₂ is a hydrogen atom or a carbon number of 1 to 4.
The positive photoresist composition according to claim 2, which is an alkyl group of 4. The positive photoresist composition according to claim 3 , wherein R _{12 in the} general formula [II] is a hydrogen atom or a methyl group.