JPH0990626A - Positive photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance resolution, to enlarge defocus latitude, and to obtain a resist image high in heat resistance and deep UV-hardenability by using a specified alkali-soluble novolak resin and a quinonediazido compound. SOLUTION: The positive photoresist composition contains an alkali-soluble resin obtained by condensing the phenol compound represented by formula I with formaldehyde and an aromatic aldehyde compound represented by formula II, and a 1,2-quinonediazido compound. In the formulae I and II, each of R1 -R3 is, independently, H or a halogen atom or a hydroxy, alkyl, cycloalkyl, alkoxy, or alkenyl group or the like; each of R4 -R8 is, independently, H or a halogen atom, or a hydroxy, formyl, alkyl, cycloalkyl, alkoxy, alkenyl, or aryl group or the like; and at least one of R4 -R8 is H atom and at least one of the rest is an alkoxy group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation-sensitive positive photoresist composition, which has a particularly high resolution, a wide defocus latitude, a high heat resistance, and a dry etching resistance. De
ep The present invention relates to a photoresist composition for microfabrication which is rich in UV curability.

The positive photoresist according to the present invention is applied to a substrate such as a semiconductor wafer, glass, ceramics or metal by spin coating method or roller coating method at 0.5.
It is applied to a thickness of ˜3 μm. Then, heat and dry,
A circuit pattern or the like is printed through an exposure mask by UV 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. Typical fields of application include manufacturing processes for semiconductors such as ICs, manufacturing circuit boards such as liquid crystals and thermal heads, and other photofabrication processes.

[0003]

2. Description of the Related Art Positive photoresist compositions include:
Generally, a composition containing an alkali-soluble resin (for example, a novolac resin) and a naphthoquinonediazide compound as a photosensitive material is used. The naphthoquinonediazide compound used for the photosensitive material acts as a dissolution inhibitor that lowers the alkali solubility of the novolak resin by itself, but when it is decomposed by light irradiation, it produces an alkali-soluble substance and rather functions to increase the alkali solubility of the novolak resin. It is peculiar in that it is advantageous in that it is particularly useful as a photosensitive material of a positive photoresist because of its large change in properties with respect to light.

The novolak resin as a binder is
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. For example, USP-3, 666, 473, USP-4, 11 as "novolak type phenol resin / naphthoquinonediazide-substituted compound"
5, 128 and USP-4, 173, 470, etc.,
As the most typical composition, the example of "Novolak resin consisting of cresol-formaldehyde / trihydroxybenzophenone-1,2 naphthoquinone diazide sulfonate" is Thompson "Introduction Tou Microlithography" (L . F. Thomp
son "Introduction to Micro
Lithography ”) (ACS Publishing, No. 21
9, No. 9, P112-121).

Further, JP-A-6-242601 discloses a phenolic compound (phenol, m- / p-cresol, xylenol) as a novolac resin and aldehydes containing an aromatic aldehyde (benzaldehyde, hydroxybenzaldehyde). A novolak resin obtained by further condensing a low molecular weight obtained by reacting in the presence of an acid catalyst with a phenol and formaldehyde is described. Then, by incorporating an o-naphthoquinonediazide compound in this novolac resin, a photosensitive resin composition having excellent balance of various characteristics such as resolution, profile, sensitivity, depth of focus and heat resistance and having no scum can be obtained. Is listed.

Further, USP-5,266,440 describes that aromatic aldehydes (benzaldehyde, salicylaldehyde) and phenols (phenol, m- / p).
-Cresol, xylenol, naphthol, bisphenol) and, if necessary, a novolak resin consisting of a condensate of formaldehyde with a photoresist composition containing an o-quinonediazide compound. This photoresist composition has the property of excellent heat resistance.

Further, Japanese Patent Laid-Open No. 2-84414 discloses that
As the novolac resin, a novolac resin composed of a phenolic compound (phenol, m- / p-cresol), formaldehyde and a monohydroxy aromatic aldehyde is described. The novolak resin is prepared from a mixture of formaldehyde and an aldehyde including a monohydroxy aromatic aldehyde, thereby improving heat resistance,
It is described that a positive photosensitive resist having a high resolution can be obtained.

Further, JP-A-2-300751 describes a positive photoresist composition containing a novolak resin obtained by condensing a phenol compound and a hydroxyaromatic aldehyde and a photosensitizer. ing. This photoresist composition has the property that the change in the developing rate with respect to the change in the exposure amount is large, that is, the so-called γ value is large.

[0009]

However, in manufacturing a semiconductor substrate such as a VLSI, it is necessary to process an ultrafine pattern having a line width of 1 μm or less. In such applications, particularly high resolution, a wide range of defocus latitude and high heat resistance, a photoresist having high sensitivity from the viewpoint of high pattern shape reproducibility that accurately copies the shape of the exposure mask and high productivity is required, The fact is that the above-mentioned conventional positive photoresist cannot be used.

In recent years, more severe dry etching conditions have been used from the viewpoint of improving throughput,
The resist pattern obtained by exposure and development with an alkaline solution is further heated and irradiated with deep ultraviolet rays to be cured.
"eeep UV curing method" tends to be applied (for example, Masataka Endo, "Effect of far-ultraviolet irradiation of positive photoresist and its application to lithography"; Polymer Papers, Vol. 45, No. 10, pp.771-776
(Oct. 1988)). However, the conventional novolak resins mainly composed of phenol, cresol, and xylenol as mentioned above, or the novolak resins co-condensed with an aromatic aldehyde, were insufficiently cured by DeepUV.

Therefore, the object of the present invention is, particularly in the manufacture of semiconductor devices, (1) a positive photoresist composition having a high resolution, and (2) a positive photoresist composition having a wide defocus latitude. Stuff,
(3) To provide a positive photoresist composition in which the obtained resist image is excellent in heat resistance, and (4) a positive photoresist composition having deep UV curability.

[0012]

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 can be achieved by the following configurations.

An alkali-soluble resin obtained by condensing a phenol compound represented by the following general formula (1), formaldehyde and an aromatic aldehyde compound represented by the following general formula (2), and a 1,2-quinonediazide compound. A positive photoresist composition comprising:

[0014]

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Here, R _{1 to} R ₃ may be the same or different and each is a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkenyl group,
It represents an aryl group, an aralkyl group, an alkoxycarbonyl group or an arylcarbonyl group, and R _{4 to} R ₈ may be the same or different and are a hydrogen atom, a hydroxyl group, a formyl group, a halogen atom, an alkyl group, a cycloalkyl group or an alkoxy group. , An alkenyl group, an aryl group, an aralkyl group or a nitro group. However, at least one of R _{4 to} R ₈ is a hydroxyl group, and the remaining at least one is an alkoxy group.

That is, the present invention provides an alkali-soluble resin obtained by condensing a phenol compound represented by the general formula (1) with formaldehyde and an aromatic aldehyde compound represented by the general formula (2). By using, it is possible to provide a positive photoresist having high resolution, wide defocus latitude, high heat resistance, and excellent deep UV curability for imparting dry etching resistance.

The positive photoresist according to the present invention can be suitably used for dry etching treatment which requires heat resistance.

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. As the cycloalkyl group, a cyclopropyl group, a cyclopentyl group, a cycloheptyl group, and a cyclooctyl group are preferable, and a cyclohexyl group is more preferable. As the alkoxy group, methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, isopropoxy group, n-
An alkoxy group having 1 to 4 carbon atoms such as butoxy group, isobutoxy group, sec-butoxy group or t-butoxy group is preferable, and methoxy group and ethoxy group are more preferable. Examples of the alkenyl group include a vinyl group, a propenyl group,
An alkenyl group having 2 to 4 carbon atoms such as an allyl group or a butenyl group is preferable, and a vinyl group and an allyl group are more preferable. As the aryl group, a phenyl group, a xylyl group,
A toluyl group or 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. 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.

R _{1 to} R ₃ may be the same or different. Furthermore, the substitution position of each substituent is not particularly limited.

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, 2,4-xylenol, 2,6
-Xylenols such as xylenol, o-ethylphenol, m-ethylphenol, p-ethylphenol,
alkylphenols such as pt-butylphenol,
o-methoxyphenol, m-methoxyphenol, p
-Methoxyphenol, o-ethoxyphenol, m-
Ethoxyphenol, p-ethoxyphenol, 3,5
-Alkoxyphenols such as dimethoxyphenol, 2-methoxy-4-methylphenol, o-propoxyphenol, m-propoxyphenol, p-propoxyphenol, o-butoxyphenol, m-butoxyphenol, p-butoxyphenol, o- Vinylphenol, m-vinylphenol, p-vinylphenol, o-allylphenol, m-allylphenol, p
-Alkenylphenols such as allylphenol, 2,
Trimethylphenols such as 3,5-trimethylphenol, 3,4,5-trimethylphenol and 2,3,6-trimethylphenol, o-phenylphenol, m
-Arylphenols such as phenylphenol and p-phenylphenol, aralkylphenols such as o-benzylphenol, m-benzylphenol and p-benzylphenol, o-methoxycarbonylphenol, m-methoxycarbonylphenol, p-methoxycarbonyl Halogenated alkoxycarbonylphenols such as phenol, arylcarbonylphenols such as o-benzoyloxyphenol, m-benzoyloxyphenol, p-benzoyloxyphenol, o-chlorophenol, m-chlorophenol and p-chlorophenol Examples thereof include phenols, catechol, resorcinol, hydroquinone, phloroglucinol, and polyhydroxybenzenes such as pyrogallol, but are not limited thereto. Not shall.

It is also possible to use a methylol compound of phenols such as bishydroxymethyl-p-cresol.

Of these, phenol, cresols, xylenols and trimethylphenols are preferred, and m-cresol, p-cresol, o-cresol-, 2,3-xylenol, 2,5-xylenol,
3,5-xylenol, 2,6-xylenol, 3,4
-Xylenol and 2,3,5-trimethylphenol are more preferable.

Further, the phenol compound of the general formula (1) can be used in combination with other phenol compounds. For example, JP-A-5-181270 and JP-A-5-32360.
4, JP-A-5-249666, and JP-A-5-23326.
96, JP-A-60-164740, JP-A-5-32
3605, JP-A-4-226458, JP-A5-1
It can be used in combination with the polyphenols having 2 to 5 aromatic rings described in JP-A-88590 and JP-A-7-72623. Furthermore, 2,2'-dihydroxy-5,5'-dimethyldiphenylmethane can be preferably used. The combined ratio of these polyphenols is preferably 30 mol% or less, and more preferably 20 mol% or less, based on the mixture of 2,3-xylenol and the phenol compound of the general formula (1). This range is preferable in terms of sensitivity.

In R _{4 to} R ₈ 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. As the cycloalkyl group, a cyclopropyl group, a cyclopentyl group, a cycloheptyl group, and a cyclooctyl group are preferable, and a cyclohexyl group is more preferable. As the alkoxy group, methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydroxypropoxy group, isopropoxy group, n-
An alkoxy group having 1 to 4 carbon atoms such as butoxy group, isobutoxy group, sec-butoxy group or t-butoxy group is preferable, and methoxy group and ethoxy group are more preferable. 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.

However, at least one of R _{4 to} R ₈ must be a hydroxyl group. Incidentally, the substitution position of the hydroxyl group is not particularly limited. Further, at least one of the remaining groups is an alkoxy group, the number of alkoxy groups is preferably 1 and 2, and the substitution position is not particularly limited.

Specific examples of the aromatic aldehydes represented by the general formula (2) are shown below, but the compounds usable in the present invention are not limited to these.

[0028]

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[0029]

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[0030]

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Phenols represented by the general formula (1),
The mixing ratio of formaldehyde and the aromatic aldehydes represented by the general formula (2) is not particularly limited as long as the amount of the aromatic aldehydes required to sufficiently exert the effect of the present invention is used, but ( 1) Phenols 100
When it contains mol% or other phenols, the aromatic aldehyde is preferably 40 mol% or less, more preferably 0.1 to less than 30 mol% with respect to 100 mol% of the whole phenols. This range is preferable in terms of sensitivity.

Particularly preferable combinations of the phenol mixture (including other phenols) and the aromatic aldehydes represented by the general formula (2), which sufficiently exert the effects of the present invention, and their preferable mixing ratios are shown below. Show. m-cresol: 30 mol% or more and less than 90 mol% 2,3-xylenol: 10 mol% or more and less than 70 mol% Aromatic aldehydes: 0.1 mol% or more and less than 40 mol% More preferably, m-cresol: 30 Mol% or more and less than 80 mol% 2,3-xylenol: 20 mol% or more and less than 70 mol% aromatic aldehyde: 1 mol% or more and less than 30 mol% or m-cresol: 30 mol% or more and less than 90 mol% 3, 5-xylenol: 10 mol% or more and less than 70 mol% Aromatic aldehyde: 0.1 mol% or more and less than 40 mol% More preferably, m-cresol: 30 mol% or more and less than 80 mol% 3,5-xylenol: 20 Aromatic aldehydes: 1 mol% or more and less than 30 mol% or m-cresol: 30 mol% or more Less than 0 mol% p-cresol: 1 mol% or more and less than 5 mol% 2,3-xylenol: 10 mol% or more and less than 70 mol% Aromatic aldehydes: 0.1 mol% or more and less than 40 mol% More preferably, m -Cresol: 30 mol% or more and less than 80 mol% p-cresol: 1 mol% or more and less than 5 mol% 2,3-xylenol: 20 mol% or more and less than 70 mol% Aromatic aldehydes: 1 mol% or more and less than 30 mol% Is.

The following combinations are preferable as the system containing no m-cresol. 2,2'-dihydroxy-5,5'-dimethyldiphenylmethane: 1 mol% or more and less than 30 mol% o-cresol: 1 mol% or more and less than 20 mol% 2,3-xylenol: 40 mol% or more and less than 80 mol% 2 , 6-xylenol: 3 mol% or more and less than 20 mol% 2,3,5-trimethylphenol: 5 mol% or more and less than 40 mol% Aromatic aldehydes: 1 mol% or more and less than 30 mol% More preferably, 2,2 '-Dihydroxy-5,5'-dimethyldiphenylmethane: 3 mol% or more and less than 20 mol% o-cresol: 1 mol% or more and less than 10 mol% 2,3-xylenol: 40 mol% or more and less than 80 mol% 2,6- Xylenol: 3 mol% or more and less than 20 mol% 2,3,5-trimethylphenol: 5 mol% or more and less than 30 mol% Aromatic aldehydes: 1 It is at least mol% and less than 20 mol%.

In the present invention, formaldehyde is further contained as an essential component, and the amount thereof is 20 to 15 relative to 100 mol% of the phenols represented by the general formula (1).
It is preferably 0 mol%, more preferably 50 to 120 mol%. Within this range, a novolac resin having a suitable molecular weight range can be obtained, which is preferable. Formaldehyde can also be used in the form of a formaldehyde precursor, that is, paraformaldehyde, trioxane and the like. Furthermore, acetaldehyde, furfural, benzaldehyde, hydroxybenzaldehydes, crotonaldehyde, chloroacetaldehyde, etc. can be used as the third component.

Acidic catalyst used in the condensation reaction is hydrochloric acid,
Sulfuric acid, formic acid, acetic acid, p-toluenesulfonic acid, oxalic acid and the like can be used, among which oxalic acid and p-
Toluenesulfonic acid is preferred. Moreover, these can be used together.

The weight average molecular weight of the novolak resin comprising the above components of the present invention is 3000 to 20000, preferably 4000 to 18000, and more preferably 5000 to 1.
It is preferably in the range of 6000. If it is less than 3,000, the film loss of the unexposed area after development is large, and if it exceeds 20,000, the developing speed becomes low and the sensitivity is lowered.
The novolak resin of the present invention is most effective when the low molecular weight component is removed and the molecular weight after removal is within the above range. As a method for removing the low molecular weight component of the novolac resin, there are disclosed in JP-A-60-45238, 60-97347, 60-140235, 60-189739, 64-64.
14229, JP-A-1-276131, 2-6091
5, the same 2-275955, the same 2-28745, the same 4-
It is more preferable to remove it by the techniques described in the publications such as 101147, 4-122938 and the like, for example, methods such as fractional precipitation, fractional dissolution, column chromatography and the like because performances such as scum and heat resistance are improved. The amount of the low molecular weight component to be removed is preferably 20% by weight to 70% by weight,
30% to 60% by weight is more preferable. Within this range, a novolac resin having a suitable molecular weight range can be obtained, which is preferable.

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, M
w / Mn) is 1.5 to 4.0, preferably 1.8 to 3.
5, and more preferably 2.0 to 3.3. When it exceeds 4, 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.

The alkali-soluble resin that can be used together is not particularly limited as long as it is compatible with the novolak resin, but polyhydroxystyrene, acetone-pyrogallol resin, acetone-resorcinol resin and the like are preferable because they do not deteriorate the heat resistance.

In the present invention, 1,2-naphthoquinonediazide sulfonyl esters are used as the 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 '
-Pentahydroxybenzophenone, 2, 3, 4, 2 ',
4'-pentahydroxybenzophenone, 2,3,4,
2 ', 5'-pentahydroxybenzophenone, 2,4,
6,3 ', 4', 5'-hexahydroxybenzophenone,
2,3,4,3 ', 4', 5'-polyhydroxybenzophenones such as hexahydroxybenzophenone,

Polyhydroxyphenylalkylketones such as 2,3,4-trihydroxyacetophenone, 2,3,4-trihydroxyphenylpentyl ketone, 2,3,4-trihydroxyphenylhexyl ketone,

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

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

Bis (2,3,4-trihydroxybenzoyl) methane, bis (3-acetyl-4,5,6-trihydroxyphenyl) -methane, bis (2,3,4-trihydroxybenzoyl) benzene, Screw (2, 4, 6
-Bis (polyhydroxybenzoyl) alkanes such as 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'-biphenyltetrol, 2,4,2', 4'-biphenyltetrol, 2,4,6,3 ', 5'- Polyhydroxybiphenyl such as biphenyl pentol, 2,4,6,2 ', 4', 6'-biphenylhexol, 2,3,4,2 ', 3', 4'-biphenylhexol Kind,

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 ', 3 ", 4"-octahydroxy-5,5'-diacetyltriphenylmethane,
2,4,6,2 ', 4', 6'-hexahydroxy-5,
Polyhydroxytriphenylmethanes such as 5′-dipropionyltriphenylmethane,

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-4,5,6,5 ', 6', 7'-polyhydroxyspirobi-indanes such as hexol,

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

Flavono pigments such as morin, quercetin and 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 (3,3
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 and the like are described in JP-A-4-253058. A polyhydroxy compound of

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 (2,2
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-trihydroxyoxybenzoyl) 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.

Further, it is also possible to use a low-nuclear substance of a phenol resin such as a novolak resin.

Furthermore, the polyhydroxy compounds shown below can also be used.

[0060]

[Chemical 6]

[0061]

[Chemical 7]

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 product obtained is purified after washing with water and dried.

In the usual esterification reaction, a mixture having different esterification numbers and esterification positions can be obtained. However, only certain specific isomers can be selected by selecting the synthesis conditions or the structure of the polyhydroxy compound. It can also be esterified. The esterification rate referred to in the present invention is defined as an 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 desired, 1,2-naphthoquinonediazide-5-sulfonyl chloride and 1,2-naphthoquinonediazide-4-sulfonyl chloride may be used in combination. The reaction temperature in the above method is usually -2.
It is 0 to 60 ° C, preferably 0 to 40 ° C.

When the photosensitive compound synthesized by the above-mentioned method is used as a resin composition, it may be used alone or as a mixture of two or more kinds thereof in an alkali-soluble resin. Is 5 to 150 parts by weight, preferably 20 to 10 parts by weight, relative to 100 parts by weight of the novolak resin.
0 parts by weight. If the use ratio is less than 5 parts by weight, the residual film rate is remarkably lowered, and if it exceeds 150 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'-tetrakis (4 -Hydroxyphenyl)]-xylene and the like can be mentioned.

These polyhydroxy compounds can be added in an amount of usually 100 parts by weight or less, preferably 5 to 70 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,
Propylene glycol monomethyl ether propionate or 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,
High-boiling solvents such as N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and benzylethyl 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 alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether, and polyoxyethylene nonyl. Polyoxyethylene alkyl allyl ethers such as phenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters such as 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.)
Manufactured by), Megafask F171, F173 (Dainippon Ink)
Co., Ltd.), Florard FC430, FC431 (Sumitomo 3M Co., Ltd.), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC10.
3, SC104, SC105, SC106 (Asahi Glass (
Manufactured by Shin-Etsu Chemical Co., Ltd., acrylic acid-based or methacrylic acid-based (co) polymerized Polyflow N
o. 75, No. 95 (Kyoeisha Yushi Kagaku Kogyo Co., Ltd.)
Manufactured). The amount 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 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
Use aqueous solutions of alkali amines such as alcoholamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and choline, and cyclic amines such as pyrrole and piperidine. 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 a light absorber, a cross-linking agent, an adhesion aid, etc., if necessary. The light absorbing agent is added as needed for the purpose of preventing halation from the substrate or for enhancing the visibility when applied to a 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 the Society of 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,
CIDisperse Red 1,5,7,13,17,19,43,50,54,58,65,72,
73,88,117,137,143,199 and 210, CIDisperse Viole
t 43, CIDisperse Blue 96, CIFluorescent Bright
ening Agent 112, 135 and 163, CISolvent Yellow 1
4,16,33 and 56, CI Solvent Orange 2 and 45, CI
Solvent 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 absorbing agent is usually added in an amount of 100 parts by weight or less, preferably 50 parts by weight or less, and more preferably 30 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin.

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, improvement of dry etching resistance, and the like. 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 crosslinking agents can be blended in a proportion of less than 10 parts by weight, preferably less than 5 parts by weight, based on 100 parts by weight of the photosensitive agent. If the amount of the crosslinking agent exceeds 10 parts by weight, the sensitivity is lowered, and scum (resist residue) is undesirably generated.

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, 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 promoters 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)
Performing e), developing, rinsing, and drying can provide a good resist. The present invention is also used for PS plates.

Examples of the present invention will be shown below, but the present invention is not limited thereto. In addition,% indicates weight% unless otherwise specified.

[0080]

【Example】

Synthesis of novolac resin (1) Synthesis of novolac resin (a-1) m-cresol 81.11 g, p-cresol 4.87
g, 2,3-xylenol 86.13 g and o-vanillin 22.82 g were charged in a 500 mL three-necked flask equipped with a stirrer, a reflux condenser and a thermometer, and 90 ° C.
While stirring at 5.67 g of oxalic acid dihydrate was added. 3
After 0 minutes, the bath temperature was raised to 130 ° C., and the contents were refluxed by stirring for 8.5 hours. Next, 102.65 g of formalin aqueous solution (37.32%) was added dropwise over 30 minutes. The reaction mixture was refluxed for another 4 hours.
Then, after adding 40 g of ethyl 3-ethoxypropionate, 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. Two hours were required for distillation 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 6490 (in terms of 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 (a-1) had a weight average molecular weight of 11060 (in terms of polystyrene) and a dispersity of 2.5.

(2) Synthesis of novolak resin (a-2) m-cresol 81.11 g, p-cresol 4.87
g, 2,3-xylenol 86.13 g, o-vanillin 22.82 g and formalin aqueous solution (37.32%)
12.07 g was charged into a 500 mL three-necked flask equipped with a stirrer, a reflux condenser and a thermometer, and 5.67 g of oxalic acid dihydrate was added under stirring at 90 ° C. After 30 minutes, the bath temperature was raised to 130 ° C., and the contents were refluxed by stirring for 12.5 hours. Next, 90.58 g of a formalin aqueous solution (37.32%) was added dropwise over 30 minutes. The reaction mixture was refluxed for another 4 hours. Next, after adding 40 g of ethyl 3-ethoxypropionate, the reflux condenser was replaced with a Liebig condenser,
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. Two hours were required for distillation 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 5620 (in terms of 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-
2) was obtained. The resulting novolak resin (a-2) had a weight average molecular weight of 10270 (in terms of polystyrene) and a dispersity of 2.6.

(3) Synthesis of Novolac Resin (a-3) 54.98 g of 2,3-xylenol and 45.65 g of o-vanillin were charged into a 1000 mL three-necked flask equipped with a stirrer, a reflux condenser and a thermometer. With stirring at 90 ° C., 0.86 g of p-toluenesulfonic acid was added. After 30 minutes, the bath temperature was raised to 130 ° C., and the contents were refluxed by stirring for 5 hours. Then, m-cresol 162.21 g, p-cresol 9.73 g, 2,3
-117.28 g of xylenol and 229.45 g of formalin aqueous solution (37.30%) were added dropwise over 30 minutes. The reaction mixture was refluxed for another 4 hours. Then, after adding 100 g of ethyl 3-ethoxypropionate, the bath temperature was lowered to 80 ° C. 300 mL of ion-exchanged water was added to the reaction mixture, and stirring, washing with water and decantation were repeated 3 times.

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. Two hours were required for distillation under reduced pressure. The molten alkali-soluble novolac resin was returned to room temperature and recovered. The weight average molecular weight of the obtained novolac resin was 3930 (in terms of polystyrene).

1000 g of 100 g of this novolak resin
Was dissolved in acetone, and 1500 g of n-hexane was added with stirring, and the mixture was further stirred at room temperature for 30 minutes, and 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 a solid novolak (a-3). The resulting novolak resin (a-
The weight average molecular weight of 3) was 5890 (in terms of polystyrene), and the dispersity was 2.5.

(4) Novolac resins (a-4) to (a-
Synthesis of 10) Monomers and aromatic aldehydes shown in Table 1 were charged in predetermined weights, and other polymerization and fractionation were carried out in the same manner as in Example (1), and novolak resins (a-4) to (a-10) were obtained. Got (In Table 1, the charged amount of monomer represents a molar ratio, the total charged amount of monomer was 1.5 mol in total. Further, the charged amount of aromatic aldehyde was shown in mol% with respect to the charged amount of monomer (1.5 mol). (5) Synthesis of novolac resin (a-11) 2,2'-dihydroxy-5,5'-dimethyldiphenylmethane 14.27 g, o-cresol 5.41 g,
198.53 g of 2,3-xylenol, 68.10 g of 2,3,5-trimethylphenol, 24.43 g of 2,6-xylenol and 38.04 g of o-vanillin were added to 1 L of a stirrer, a reflux condenser and a thermometer. The mixture was placed in a three-necked flask and 50 g of ethyl 3-ethoxypropionate was further added. While stirring the mixture at 90 ° C., 9.46 g of oxalic acid dihydrate was added. After 1 hour, change the bath temperature to 13
The contents were refluxed by raising the temperature to 0 ° C. and further stirring for 30 hours. Then 9.46 g of oxalic acid dihydrate was added again before the reaction mixture was refluxed for another 13 hours. Then, formalin aqueous solution (37.30%) 24
5.30 g was added and refluxed at 130 ° C. for 12 hours, and 25 g of ethyl 3-ethoxypropionate was added. After refluxing for 6 hours, 25 g of ethyl 3-ethoxypropionate was added again. Next, 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. It took 3 hours to distill off. The heating was stopped, and when the internal temperature dropped to 180 ° C., 620 g of ethyl lactate was gradually added dropwise to obtain a solution of novolac in ethyl lactate. The weight average molecular weight of the resulting novolak resin (a-11) was 3
The degree of dispersion was 250 (in terms of polystyrene) and the degree of dispersion was 2.3.

[0088]

[Table 1]

In the table, * m; m-cresol p; p-cresol 2,3Xy; 2,3-xylenol 2,5Xy; 2,5-xylenol

(6) Novolac resins (b-1) to (b-
Synthesis of 2) The monomers and aromatic aldehydes shown in Table 2 were charged in predetermined weights, and the polymerization and fractionation were carried out in the same manner as in the synthesis (1) of the novolak resin, except that novolak resins (b-1) to (b-) were used.
Got up to 2). (In Table 2, the monomer charge represents the molar ratio, and the total amount of the monomer charged was 1.5 mol in total.
The charged amount of the aromatic aldehyde is the charged amount of the monomer (1.
5 mol). )

[0091]

[Table 2]

(7) Synthesis of novolac resin (b-3) m-cresol 81.11 g, p-cresol 4.87
90 g of 2,3-xylenol and 159.76 g of o-vanillin were charged into a 500 mL three-necked flask equipped with a stirrer, a reflux condenser and a thermometer.
With stirring at 1.degree. C., 1.95 g of concentrated hydrochloric acid was added dropwise. 30 minutes later,
The bath temperature was raised to 130 ° C., and the reaction was further stirred for 8.5 hours. Then, 40 g of ethyl 3-ethoxypropionate was added, the reflux condenser was replaced with a Liebig condenser, the bath temperature was raised to 200 ° C. over about 1 hour, and hydrochloric acid, water and the like were removed. 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. Two hours were required for distillation 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 5170 (in terms of 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 (b-
3) was obtained. The obtained novolak resin (b-3) had a weight average molecular weight of 9730 (in terms of polystyrene) and a dispersity of 2.6.

Synthesis of Photosensitive Material (8) Synthesis of Photosensitive Material (S-1) 62.9 g of the compound (1) shown in Table 3, 53.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 800 mL of acetone were mixed. It was charged in a single-necked flask and uniformly dissolved. Then, 21.2 g of triethylamine was gradually added dropwise and reacted at 25 ° C. for 3 hours. 1% reaction mixture
Pour into 3 L of hydrochloric acid aqueous solution, separate the resulting precipitate by filtration, wash with water,
It was dried to obtain a photosensitive material (S-1).

(9) Synthesis of Photosensitive Material (S-2) 53.8 g of the compound (2) described in Table 3, 53.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 800 mL of acetone were placed in a three-necked flask. Charged and dissolved uniformly. Then, 21.2 g of triethylamine was gradually added dropwise and reacted at 25 ° C. for 3 hours. 1% reaction mixture
Pour into 3 L of hydrochloric acid aqueous solution, separate the resulting precipitate by filtration, wash with water,
It was dried to obtain a photosensitive material (S-2).

(10) Synthesis of Photosensitive Material (S-3) 56.5 g of the compound (3) shown in Table 3, 53.7 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 800 mL of acetone were placed in a three-necked flask. Charged and dissolved uniformly. Then, 21.2 g of triethylamine was gradually added dropwise and reacted at 25 ° C. for 3 hours. 1% reaction mixture
Pour into 3 L of hydrochloric acid aqueous solution, separate the resulting precipitate by filtration, wash with water,
It was dried to obtain a photosensitive material (S-3).

[0097]

[Table 3]

(11) Preparation and Evaluation of Positive Photoresist Composition Novolak resin (a-) obtained in the above (1) to (6)
1) to (a-11) and (b-1) to (b-3), and the photosensitive materials (S-1) to (S-) obtained in (7) to (9) above.
3), the solvents (Y-1) to (Y-4) and the polyhydroxy compounds (P-1) to (P-3) shown in Table 4 were mixed at a ratio shown in Table 5 to form a uniform solution. , Hole diameter 0.10μ
m using a microfilter to prepare a photoresist composition. This photoresist composition was applied on a silicon wafer using a spinner and dried on a vacuum adsorption hot plate at 90 ° C. for 60 seconds to give a film thickness of 1.
A resist film of 02 μm was obtained.

[0099]

[Table 4]

[0100]

[Table 5]

This film was exposed 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% aqueous solution of 2.38% tetramethylammonium hydroxide. It was developed for 1 minute, washed with water for 30 seconds and dried. The resist pattern on the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the resist. Table 6 shows the results.

The sensitivity was defined as the reciprocal of the exposure dose for reproducing a 0.4 μm mask pattern, and was shown as a value relative to the sensitivity of Comparative Example 1. The resolving power indicates a limiting resolving power at an exposure amount for reproducing a mask pattern of 0.40 μm. The defocus latitude was evaluated by observing a cross section of a focus width at which a resist pattern of 0.40 μm in effective sensitivity is separated without film loss with a scanning electron microscope.

The heat resistance was indicated by the temperature at which the edge of the 0.50 μm line pattern started to be rounded. Deep U
As for the V-curability, the resist pattern formed on the silicon wafer by the above-described method is evaluated by AE manufactured by Dainippon Screen Co., Ltd.
While heating and raising the temperature using the W-612 device (initial temperature 1
Deep ultraviolet rays were irradiated for 60 seconds at a temperature of 00 ° C. and a final temperature of 200 ° C., and then the resist pattern was immersed in isoamyl acetate for 1 minute (etching), dried, and observed by a scanning electron microscope for evaluation. The symbols in the table are shown below.

◯: When the resist pattern is not etched at all, and the pattern is neither deformed nor roughened (cured completely). Δ: When slight etching was observed between the substrate and the resist pattern, or when the pattern was slightly roughened or deformed. X: When the space between the substrate and the resist pattern is greatly etched, or the pattern is largely deformed or roughened.

[0105]

[Table 6]

From the evaluation results shown in Table 6, the positive photoresist according to the present invention is excellent in relative sensitivity, resolution, defocus latitude and heat resistance, and at the same time, Dee.
It was confirmed that the pUV curability was excellent.

[0107]

As described above, according to the present invention,
It has a high resolution and a wide defocus latitude, and the resulting resist image has excellent heat resistance.
A positive photoresist composition rich in UV curability is obtained.

Claims (1)

[Claims] 1. An alkali-soluble resin obtained by condensing a phenol compound represented by the following general formula (1) with formaldehyde and an aromatic aldehyde compound represented by the following general formula (2), and 1,2-quinonediazide. A positive photoresist composition comprising a compound. Embedded image Here, R _{1 to} R ₃ may be the same or different and each is a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkenyl group, an aryl group, an aralkyl group, an alkoxycarbonyl group or an arylcarbonyl. It represents a group, R ₄ to R _8, which may be the same or different, a hydrogen atom, a hydroxyl group, a formyl group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkenyl group, an aryl group, an aralkyl group or a nitro group Indicates. However, at least one of R _{4 to} R ₈ is a hydroxyl group, and the remaining at least one is an alkoxy group.