JP3133881B2 - Ionizing radiation-sensitive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a UV-ray, a UV-ray, an X-ray, an electron beam, a molecule containing a water-insoluble alkali-soluble novolak resin, a mixture of specific quinonediazide compounds and a water-insoluble alkali-soluble low-molecular compound additive. Line, γ
The present invention relates to a positive photoresist composition which is sensitive to radiation such as radiation and synchrotron radiation. More specifically, the present invention relates to a photoresist composition for fine processing, which can obtain a high resolving power irrespective of a change in film thickness, has little development residue, and is excellent in development latitude. The positive photoresist according to the present invention is applied to a semiconductor wafer, or a substrate of glass, ceramics, metal, or the like by a spin coating method, a roller coating method, or another coating method to a thickness of 0.5 to 3 μm.
It is applied to a thickness of about m. Thereafter, the film is heated and dried, and a circuit pattern or the like is baked through an exposure mask by irradiation with ultraviolet rays or the like. Further, the substrate can be processed in a pattern by etching using the positive image as a mask. Typical fields of application are the manufacturing process of semiconductors such as ICs, the manufacture of circuit boards such as liquid crystals and thermal heads, the manufacture of magnetic bubble memory devices, and other photofabrication processes.

[0002]

2. Description of the Related Art Conventionally, ionizing radiation-sensitive resin compositions have been used in photofabrication processes such as the manufacture of semiconductor devices such as ICs and magnetic bubble memories. Among them, a positive photoresist composition having particularly high resolution is used. As the positive photoresist composition, a composition containing an alkali-soluble resin binder such as novolak and a naphthoquinonediazide compound as a photosensitive material is generally used. For example, US Pat. Nos. 3,666,473 and 4,115, as “Novolak-type phenolic resin / naphthoquinonediazide-substituted compound”
No. 128 and 4,173,470, and the most typical composition is "a novolak resin composed of cresol-formaldehyde / trihydroxybenzophenone-
Examples of "1,2-naphthoquinonediazide sulfonic acid ester" are Thompson's "Introduction to Microlithography" (LF Thompson "Intr").
option to Microlithograph
phy ") (ACS Publishing, No. 219, P112-
121).

A novolak resin as a binder can be dissolved in an aqueous alkali solution without swelling, and when used as a mask for etching, the resulting image has high resistance to plasma etching, in particular. Particularly useful for applications. Further, the naphthoquinonediazide compound used in the photosensitive material itself acts as a dissolution inhibitor that reduces the alkali solubility of the novolak resin, but when decomposed by irradiation with light, generates an alkali-soluble substance, and rather increases the alkali solubility of the novolak resin. 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 property change to light. From this point of view, many positive photoresists containing a novolak resin and a naphthoquinonediazide-based photosensitive material have been developed and put into practical use. In particular, there has been remarkable progress in the development of resist materials for higher resolution, and sufficient results have been achieved in line width processing down to submicron.

Hitherto, it has been advantageous to use a resist having a high contrast (γ value) in order to enhance the resolution and obtain an image with good pattern shape, and technical development of a resist composition suitable for such purpose has been carried out. Have been. There are numerous patents and reports disclosing this technology, and many patent applications have been filed, especially regarding the technology of novolak resin, which is a main component of positive photoresists, regarding its monomer composition, molecular weight distribution, and synthesis method. , With some success.

[0005] Attempts to improve the properties of the resist by giving the novolak resin a certain specific molecular weight distribution are known. For example, JP-A-1-105243 describes that a novolak resin having a distribution in which the molecular weight in the range of 500 to 5000 is 30% or less is preferable. JP-A-62-227144 and JP-A-63-2044 show that there is a preferable range for the ratio of the specific molecular weight region in the molecular weight distribution.
Nos. 60-97347 and 60-18973.
No. 9 describes a novolak resin from which low molecular weight components have been separated and removed, and JP-A 60-45238 describes the use of a resin having a degree of dispersion of 3 or less as used in the present invention.

[0006] Regarding the photosensitive material, which is another main component, many structures that are effective for increasing the contrast have been disclosed. By utilizing this knowledge to design a positive photoresist, it has become possible to develop an ultra-high resolution resist capable of resolving a pattern having a size comparable to the wavelength of light.

However, the degree of integration of integrated circuits is increasing, and in the production of semiconductor substrates such as VLSI,
It has become necessary to process ultrafine patterns having a line width of 0.5 μm or less. In such applications, there is a demand for a photoresist having a particularly high stable resolving power and a wide developing latitude for ensuring a constant processing line width. Further, in order to prevent processing defects in the circuit, it is required that resist residue does not occur in the developed resist pattern.

A low molecular compound having an aromatic hydroxyl group is usually used as a dissolution accelerator for the purpose of improving sensitivity, and many examples of addition to a resist composition are disclosed. However, when such a compound is added, film loss in an unexposed portion is usually increased, and as a result, the shape of the resist is deteriorated. In general, the development latitude also decreases because the development speed is increased. Therefore, a structure of a preferable compound has been selected so as to minimize these phenomena.

Attempts have also been made to improve the sensitivity and developability of the resist by incorporating a specific compound into the resist composition. For example, Japanese Patent Application Laid-Open No. 61-141441 discloses a positive photoresist composition containing trihydroxybenzophenone. The sensitivity and developability of the positive photoresist containing trihydroxybenzophenone are improved, but heat resistance is deteriorated by the addition of trihydroxybenzophenone, and there is a problem in that the unexposed portion increases in film thickness.

Therefore, it has been desired to develop a resist having a wide developing latitude, high sensitivity, good resolution and high heat resistance.

In the formation of an ultra-fine pattern having a thickness of 0.5 μm or less, even if a certain resolution is obtained at a certain coating film thickness, it can be obtained only by slightly changing the coating film thickness. It has been found that there is a phenomenon (hereinafter, referred to as “thickness dependence”) in which the resolution is deteriorated. Surprisingly, a slight change in the film thickness by a few hundredths of a micrometer significantly changes the resolving power, and more or less this tendency is found in any of the typical positive photoresists currently on the market. There was found. Specifically, when the thickness of the resist film before exposure changes within a range of λ / 4n (λ is an exposure wavelength, and n is a refractive index of the resist film at that wavelength) with respect to a predetermined film thickness, it corresponds to this. Thus, the resolving power obtained varies.

In particular, it has been found that, when the contrast of a resist is to be increased so as to obtain a pattern having a high resolution and a rectangular cross-sectional shape, the film thickness dependence often increases. When a semiconductor substrate is actually processed, a pattern is formed using a resist film applied with a slightly different thickness at each location due to unevenness on the substrate surface and unevenness of the applied film thickness. Therefore, in performing fine processing near the resolution limit using a positive photoresist, this film thickness dependency is an obstacle. The problem of the film thickness dependence is described in, for example, SPIE Processing.
The existence thereof is pointed out in Vol. 1925, p. 626 (1993), and it is described that this is caused by the multiple reflection effect of light in the resist film and correlates with the phenomenon of insolubilization of the resist surface. ing.

However, it has not been known at all how to design the composition of the resist material in order to reduce the dependency on the film thickness and obtain a high resolution regardless of the film thickness.

[0014]

SUMMARY OF THE INVENTION Accordingly, a first object of the present invention is to provide a positive photoresist for ultrafine processing having a high resolution and a small thickness dependency. The film thickness dependency in the present invention means that the obtained resolving power changes when the resist film thickness before exposure changes in the range of λ / 4n.

Another object of the present invention is to provide a positive photoresist having a wide development latitude and less generation of development residues. Here, the development latitude can be represented by the development time dependence or the temperature dependence of the resist line width or sensitivity obtained by development. Further, the development residue refers to a trace amount of insoluble resist remaining between fine patterns after development, which can be observed with a scanning electron microscope or the like.

[0016]

Means for Solving the Problems The inventors of the present invention have paid careful attention to the above-mentioned properties and made intensive studies. As a result, the present inventors have found that a water-insoluble alkali-soluble resin, a water-insoluble alkali-soluble low-molecular compound and an ionizing radiation-sensitive compound are contained. In the ionizing radiation-sensitive resin composition, the ionizing radiation-sensitive compound has a general formula described below.
A naphthoquinonediazidosulfonic acid diester compound (A), which is a water-insoluble alkali-soluble low-molecular compound having three phenolic hydroxyl groups , represented by (A1) or (A2), and a compound represented by the following general formula (B1) or (B2) )
That, phenol - and wherein naphthoquinonediazide sulfonic acid diester compound of the water-insoluble alkali-soluble low-molecular compound having four or Le hydroxyl groups of the mixture of (B), and that the mixture is at least 30% of the sensitive ionizing radiation compound It has been found that the above object can be achieved by using the ionizing radiation-sensitive resin composition described above, and the present invention has been accomplished.

Here, a description will be given of the relation between the present invention and a known technique which forms a part of the constituent elements of the present invention. Some of the skeletal compounds of the ionizing radiation-sensitive compound (A) or (B) used in the present invention are described in, for example, US Pat. No. 5,178,986, JP-A-2-296249 and JP-A-2-296248. However, the photosensitive compounds described are essentially based on naphthoquinonediazidosulfonic acid complete esters of phenolic hydroxyl groups. In positive photoresists using these as a composition of a water-insoluble alkali-soluble resin and a water-insoluble alkali-soluble low-molecular compound, development residues are likely to occur, the development latitude is narrow, and the film thickness dependence is low. There was a problem that it was big.

However, the effect of the present invention is to provide an ionizing radiation-sensitive resin composition containing a water-insoluble alkali-soluble resin, a water-insoluble alkali-soluble low molecular weight compound and an ionizing radiation-sensitive compound. Naphthoquinonediazidosulfonic acid diester compound (A), a specific water-insoluble alkali-soluble low-molecular compound having three phenolic hydroxyl groups, and naphthoquinonediazide, a specific water-insoluble alkali-soluble low-molecular compound having four phenolic hydroxyl groups This is a unique effect exhibited only when the mixture with the sulfonic acid diester compound (B) accounts for 30% or more of the total ionizing radiation-sensitive compound.

That is, when the mixture of the ionizing radiation-sensitive compound is combined with the water-insoluble alkali-soluble resin defined in the present invention and the water-insoluble alkali-soluble low molecular weight compound,
As expected, while improving the resolution of the resist by properly balancing the alkali dissolution inhibiting action of the ionizing radiation-sensitive compound and the alkali dissolution accelerating action of its photodegradation product, it is quite surprising that the development is wider than that obtained by any one alone. It gives latitude and good film thickness dependence. Hereinafter, embodiments of the present invention will be described in detail.

The sensitive ionizing radiation-compound used in the present invention (A) is phenol - a naphthoquinone diazide sulfonic acid diester compound of the water-insoluble alkali-soluble low-molecular compound having three Le hydroxyl groups, represented by the following general formula (A1)
Or naphthoquinone diazide sulfonic acid diester compound represented by the general formula (A2).

[0021]

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Here, R _{1 to} R ₈ and R _{20 to} R ₂₄ each represent a hydrogen atom, —CN, —X—Ra ₁ or a halogen atom. In the case of a group containing a large alkyl group, it depends on the film thickness. A hydrogen atom, a lower alkyl group or a lower alkoxy group is preferable, respectively, because the properties and development residue tend to be deteriorated. Particularly, a hydrogen atom, a methyl group, an ethyl group or a methoxy group is preferable.

X _{1 to} X ₂ are a single bond, a carbonyl group, a sulfide group, a sulfonyl group or —C (R _b1 ) (R _b2 )
Represents-. However, when 1 = 0, X ₁ represents a group represented by the following general formula A ₁₁ or A ₁₂ .

[0024]

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X _{1 to} X ₂ and X _{a each} represent _a sulfide group, a sulfone group or a -C group in view of the solubility of the ionizing radiation-sensitive compound (A) in a coating solvent, cost, and ease of industrial production.
A group represented by (R _b1 ) (R _b2 ) — or, when 1 = 0, X ₁ is preferably a group represented by the general formula A ₁₁ or A ₁₂ .

X ₃ represents a group represented by the following formula A ₂₁ or A ₂₂

[0027]

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[0028] Among these, represented by the general formula A ₂₂ are preferred.

R ₉ , R ₁₂ -R ₁₇ , R ₂₅ -R ₃₁ , R _b1 , R
_b2 represents a hydrogen atom, a methyl group, an ethyl group or a haloalkyl group having 1 to 2 carbon atoms, respectively, and is preferably a hydrogen atom or a methyl group from the viewpoint of the film thickness dependency and the performance of development residue. R _b1 and R _b2 , R ₂₅ and R ₂₆ , R ₂₈ and R ₂₉ , R ₃₀ and R ₃₁
May be linked together to form an alicyclic hydrocarbon residue.

R ₁₀ , R ₁₁ , R _a3 , R _a4 , R ₁₈ and R ₁ each represent a hydrogen atom, —X—R _a1 , —CN or a halogen atom, and from the same viewpoint, a hydrogen atom and a lower alkyl Groups or lower alkoxy groups are preferred. Particularly, a hydrogen atom, a methyl group, an ethyl group or a methoxy group is preferable.

Z ₁ represents a single bond or a trivalent alicyclic hydrocarbon group formed together with CR ₉ , and more preferably a single bond.

Z ₂ is preferably -O-, k and l are each preferably 1, and m, n and q are each preferably 1.

R and s each represent 1 or 2. However, r + s = 3.

D _{1 to} D ₇ each represent a hydrogen atom or a naphthoquinonediazide-4 (and / or 5) -sulfonyl group.

Among these, the ionizing radiation-sensitive compound (A) is preferably an ionizing radiation-sensitive compound represented by the general formula (A1), and particularly preferably, l = 1.

Specific examples of the ionizing radiation-sensitive compound (A) useful in the present invention are shown below, but the compounds usable in the present invention are not limited to these. D represents a hydrogen atom or a naphthoquinonediazide-4 (and / or 5) -sulfonyl group, respectively.

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The sensitive ionizing radiation compound (B) used in the present invention are phenol - a naphthoquinone diazide sulfonic acid diester compound of the water-insoluble alkali-soluble low-molecular compound having four or Le hydroxyl groups, represented by the following general formula (B1)
Or naphthoquinone diazide sulfonic acid diester compound represented by the general formula (B2).

[0047]

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Here, R _{32 to} R ₄₆ and R ₄₉ each represent a hydrogen atom, —CN, —XR _a1 or a halogen atom. In the case of a group containing a large alkyl group, the dependence on the film thickness and A hydrogen atom, a lower alkyl group, a lower alkoxy group, or a chloro atom is preferable, since the development residue tends to deteriorate. Particularly, a hydrogen atom, a methyl group, an ethyl group or a methoxy group is preferable.

R ₄₇ represents a hydrogen atom, a methyl group, an ethyl group, a haloalkyl group having 1 to 2 carbon atoms or R _c , and among them, a hydrogen atom, a methyl group or R _c is preferable. Wherein R _c represents a group represented by the following general formula B _21.

[0050]

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R ₄₈ represents a hydrogen atom, a methyl group, an ethyl group, a haloalkyl group having 1 to 2 carbon atoms or R _d , and among them, a hydrogen atom, a methyl group or R _d is preferable. Wherein R _d represents a group represented by the following general formula B _22.

[0052]

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R ₅₀ and R ₅₁ each represent a hydrogen atom, —CN,
—X— _Ra1 or a halogen atom. Among them, a hydrogen atom, a methyl group or a methoxy group is preferred.
However, when R ₄₇ ≠ R _c and R ₄₈ ≠ R _d , R ₅₀ and R ₅₁ each represent R _c .

X _{4 to} X ₆ are a single bond, a carbonyl group, a sulfide group, a sulfonyl group or —C (R _b1 ) (R _b2 )
Represents a single bond because of the solubility of the ionizing radiation-sensitive compound (B) in the coating solvent, the cost, and the ease of industrial production.
Sulfide group, sulfonyl group or -C (R _b1 )
A group represented by (R _b2 ) _-is preferred. .

R _{52 to} R ₅₉ each represent a hydrogen atom, —CN,
-X- _Ra1 or a halogen atom, but a hydrogen atom,
A methyl group or a methoxy group is preferred.

X ₇ and X ₈ are a single bond or-(CR
It represents a group represented by _{- 60 R 61) u (CH} = CH) v.
R ₆₀ and R ₆₁ are each preferably a hydrogen atom or a methyl group.

Z ₃ represents a C 1-6 tetravalent alkyl group residue, preferably a carbon atom.

D _{8 to} D ₁₆ each represent a hydrogen atom or a naphthoquinonediazide-4 (and / or 5) -sulfonyl group.

T is preferably 0 or 1, and u and x are preferably 0 or an integer of 1 to 4.

Y, v and w are each 0 or 1. However, when R ₄₇ ≠ R _c and R ₅₀ ≠ R _c and R ₅₁ ≠ R _c , y = 1,
w = 1, otherwise y = 0.

However, among D _{1 to} D ₁₆ , general formula (A1):
In each of the ionizing radiation-sensitive compounds represented by (A2), (B1) or (B2), two per molecule are naphthoquinonediazide-4 (and / or 5) -sulfonyl groups.

The ionizing radiation-sensitive compound used in the present invention is selected from the viewpoints of the action of inhibiting the dissolution of the water-insoluble alkali-soluble resin, the development residue of the ionizing radiation-sensitive composition, the high resolution performance and the like.
Particularly preferred is an ionizing radiation-sensitive compound in which the naphthoquinonediazidosulfonic acid ester group is located at the terminal of the molecular chain of the ionizing radiation-sensitive compound.

Of these, the ionizing radiation-sensitive compound (B) is preferably an ionizing radiation-emitting compound represented by the general formula (B1). Specific examples of the ionizing radiation-sensitive compound (B) useful in the present invention are shown below, but the compounds that can be used in the present invention are not limited thereto. D represents a hydrogen atom or a naphthoquinonediazide-4 (and / or 5) -sulfonyl group, respectively.

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The ratio of the ionizing radiation compound (A) to the ionizing radiation compound (B) in the mixture of the ionizing radiation compound used in the present invention is such that the ratio of the ionizing radiation compound (A) is large. If the amount is too large, the film thickness dependence and the performance of development residues tend to deteriorate. If the amount of the ionizing radiation-sensitive compound (B) is too large, the film thickness during development, development latitude, high resolution performance, etc. Because it tends to deteriorate,
The range is from 0.02 to 20, preferably from 0.1 to 5. Particularly preferably, it is in the range of 0.2 to 4.

The mixture of the ionizing radiation-sensitive compound (A) and the ionizing radiation-sensitive compound (B) used in the present invention contains a specific water-insoluble alkali-soluble resin and a specific water-insoluble alkali-soluble low-molecular compound. It is preferable to use the composition as a composition.

As the specific water-insoluble alkali-soluble resin, a water-insoluble alkali-soluble novolak resin having a ratio of the weight average molecular weight to the number average molecular weight of 1.2 to 5 is preferable.
It is difficult to industrially produce a water-insoluble alkali-soluble novolak resin having a ratio of the weight average molecular weight to the number average molecular weight of less than 1.2, and if the ratio exceeds 5, the development latitude becomes narrow, and the development residue becomes small. Tends to increase, which is not desirable. A person skilled in the art can produce a water-insoluble alkali-soluble resin having a small ratio between the weight average molecular weight and the number average molecular weight, for example, with reference to JP-A-4-122938.

Among these, at least one of the water-insoluble alkali-soluble resins synthesized by a condensation reaction of an aldehyde compound with phenol, cresol, xylenol, trimethylphenol or a mixture of two or more thereof. Novolak resin having a weight average molecular weight to number average molecular weight ratio of 1.2 to 5, and a weight average molecular weight of 60
And the water-insoluble alkali-soluble resin is p-cresol, o-cresol,
At least one novolak resin synthesized by a condensation reaction of a mixture of 2,3-xylenol, 2,6-xylenol, and trimethylphenol with an aldehyde compound, wherein the novolak resin has a weight average molecular weight and a number average molecular weight. The ratio is 1.2 ~
4.0 and a weight average molecular weight of 1500 to 50
A water-insoluble alkali-soluble novolak resin of 00 is more preferred.

The specific water-insoluble alkali-soluble low molecular weight compound is a water-insoluble alkali-soluble low molecular weight compound having a total carbon number of 60 or less in one molecule and having 2 to 10 phenolic hydroxyl groups in one molecule. Low molecular weight compounds are preferred. Further, the water-insoluble alkali-soluble low molecular weight compound has a ratio of phenolic hydroxyl group to aromatic ring of 0.5 to 1.4, and a total number of carbon atoms in one molecule of 12 to 50,
Further, it is preferably at least one water-insoluble alkali-soluble low-molecular compound having 2 to 10 phenolic hydroxyl groups in one molecule. Among these compounds, compounds that increase the alkali dissolution rate of the alkali-soluble resin when added to the water-insoluble alkali-soluble resin are particularly desirable.

When the compound has more than 60 carbon atoms, the effect of the present invention is reduced. If the number is smaller than 12, new drawbacks such as a decrease in heat resistance occur.

In order to exert the effects of the present invention, it is necessary to have at least two phenolic hydroxyl groups in the molecule. If the number exceeds 10, the effect of improving the development latitude is lost. When the ratio of the phenolic hydroxyl group to the aromatic ring is less than 0.5, the film thickness dependency is large,
Also, the development latitude tends to be narrow. 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 preferred amount of the low molecular weight compound is 2 to 50% by weight, more preferably 10 to 40% by weight, based on the alkali-soluble resin. An addition amount exceeding 50% by weight is not preferable because new development defects such as development residue deterioration and pattern deformation during development occur.

The water-insoluble alkali-soluble low molecular weight compounds having an aromatic hydroxyl group used in the present invention can be prepared, for example, by the methods described in JP-A-4-122938, JP-A-2-28531, US Pat. No. 4,916,210, EP 219294 and the like. Can be easily synthesized by those skilled in the art with reference to Specific examples of the low molecular weight compound having an aromatic hydroxyl group useful in the present invention are shown below, but the compounds that can be used in the present invention are not limited thereto.

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As the water-insoluble alkali-soluble resin used in the present invention, novolak resin, vinylphenol resin, acetone-pyrogallol resin, acetone-resole resin,
A maleimide copolymer, an N- (hydroxyphenyl) maleimide (co) polymer, a styrene-maleic anhydride copolymer, a polymer containing a carboxyl group, a sulfonyl group, a lactone group, a phosphonic acid group, or the like is used. I can do it.

The water-insoluble alkali-soluble novolak resin which can be used in the present invention may be a mixture of a substituted phenol alone or a mixture of two or more thereof in the presence of an acidic catalyst.
It is obtained by condensing 0.6 to 1.2 moles of aldehydes with respect to moles. The substituted phenols used here include phenol, p-cresol, m-cresol, o-cresol, 2,3-dimethylphenol,
2,4-dimethylphenol, 2,5-dimethylphenol, 2,6-dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, 2,3,4
-Trimethylphenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, 2,4
5-trimethylphenol, methylenebisphenol,
Methylenebis-cresol, resorcin, catechol, 2-methylresorcin, 4-methylresorcin, o
-Chlorophenol, m-chlorophenol, p-chlorophenol, 2,3-dichlorophenol, p-methoxyphenol, m-methoxyphenol, p-butoxyphenol, o-ethylphenol, m-ethylphenol, p-ethylphenol , 2,3-diethylphenol, 2,5-diethylphenol, p-isopropylphenol, p-tert-butylphenol, α
-Naphthol, β-naphthol, 4-phenylphenol and the like can be used alone or as a mixture of a plurality of them. Among these, it is particularly preferable to use a plurality of mixtures of alkylphenols such as cresol, dimethylphenol and trimethylphenol. Further, a monomethylol compound or a dimethylol compound of these phenols can be used as the substituted phenol.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde, hydroxybenzaldehyde, glyoxal, chloroacetaldehyde, dichloroacetaldehyde, bromoacetaldehyde, acrolein, methacrolein, crotonaldehyde, and acrolein methyl acetal. , Furfural and the like can be used alone or in a mixture of a plurality. Hydrochloric acid as an acidic catalyst,
Sulfuric acid, nitric acid, formic acid, acetic acid, oxalic acid, p-toluenesulfonic acid and the like can be used. The water-insoluble alkali-soluble resin of the present invention preferably has an average molecular weight defined by Mw value in the range of 1,000 to 25,000, more preferably in the range of 2,000 to 15,000. When the Mw value is too large, the effect of the present invention for obtaining a wide development latitude or the like cannot be obtained.

The ionizing radiation compound used in the present invention may be a mixture of the ionizing radiation compound (A) and the ionizing radiation compound (B) mixed with another ionizing radiation compound. Can be done. Other ionizing radiation-sensitive compounds include ionizing radiation-sensitive alkali dissolution inhibitor compounds,
There are ionizing radiation-sensitive acid generator compounds and the like. When an ionizing radiation-sensitive acid generator compound is used, it is preferable to further use an acid labile group-containing alkali dissolution inhibitor compound in combination.

Examples of the ionizing radiation-sensitive alkali dissolution inhibitor compound include quinonediazide compounds, diazoketone compounds, azide compounds, orthonitrobenzyl compounds, orthonitroarylsulfonyl ester compounds and polyolefin sulfone compounds. There is.

The quinonediazide compounds include 1,2
-Naphthoquinonediazide-5-sulfonic acid, 1,2-naphthoquinonediazide-4-sulfonic acid or 1,2-
An ester of benzoquinonediazide-4-sulfonic acid and a polyhydroxy aromatic compound is used. As the polyhydroxy aromatic compound, for example, 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 2,3,4,3 ', 4', 5'-hexahydroxybenzophenone,
Polyhydroxyphenyl alkyl ketones such as 3,4-trihydroxyacetophenone, 2,3,4-trihydroxyphenylhexyl ketone, bis (2,4-dihydroxyphenyl) methane, bis (2,3, Bis ((poly) hydroxyphenyl) alkanes such as 4-trihydroxyphenyl) methane and bis (2,4-dihydroxyphenyl) propane-1, propyl 3,4,5-trihydroxybenzoate, Polyhydroxybenzoic acid esters such as phenyl 4,5-trihydroxybenzoate, bis (2,3,
4-trihydroxybenzoyl) methane, bis (2,3,
Bis (polyhydroxybenzoyl) alkane or bis (polyhydroxybenzoyl) aryls such as 4-trihydroxybenzoyl) benzene, ethylene glycol-
Alkylene-di (polyhydroxybenzoates) such as di (3,5-dihydroxybenzoate), 3,5,3 ′,
5'-biphenyl tetrol, 2,4,2 ', 4'-biphenyl tetrol, 2,4,6,3', 5'-biphenyl pentol, 2,4,6,2 ', 4 Polyhydroxybiphenyls such as', 6'-biphenylhexol, 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 ', Polyhydroxytriphenylmethanes such as 3 ", 4"-octahydroxy-5,5'-diacetyltriphenylmethane, 3,3,3 ', 3'-tetramethyl-1,1'-spirobi-indane -5,6,5 ',
6'-tetrol, 3,3,3 ', 3'-tetramethyl-1,
1'-spirobi-indane-5,6,7,5 ', 6', 7'-hexol, 3,3,3 ', 3'-tetramethyl-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′-hexol, 3,3-bis (3,4-dihydroxyphenyl) phthalide, 3,3-bis (2,3,4-trihydroxyphenyl) phthalide,
Polyhydroxyphthalides such as 3 ', 4', 5 ', 6'-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-
Polyhydroxybenzopyrans such as trihydroxyphenyl) -3- (3,4,5-trihydroxybenzoyloxy) -5,7-dihydroxybenzopyran;
4-trimethyl-2- (2 ', 4'-dihydroxyphenyl) -7-hydroxychroman, 2,4,4-trimethyl-2- (2', 3 ', 4'-trihydroxyphenyl) -7,
8-dihydroxychroman, 2,4,4-trimethyl-2
-(2 ', 4', 6'-trihydroxyphenyl) -5,7-
Polyhydroxyphenylchromans such as dihydroxychroman, 2,6-bis (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, 2,4,6-tris (3,
5-dimethyl-4-hydroxybenzyl) -4-methylphenol, 4,6-bis (3,5-dimethyl-4-hydroxybenzyl) pyrogallol, 2,6-bis (3,5-
Hydroxybenzylphenols such as dimethyl-4-hydroxybenzyl) -4-methylphenol, 2,6-bis (3,5-dimethyl-4-hydroxybenzyl) phloroglucinol, and flavono dyes such as quercetin and rutin In addition, a low nucleus of novolak or an analog thereof can be used. Further, a polymer containing an aromatic hydroxyl group such as an acetone pyrogallol condensed resin or polyvinyl phenol can be used in place of these low molecular compounds. Further, the hydroxyl group of the novolak itself can be substituted with quinonediazide in an appropriate amount, so that it can also function as a photosensitive material or as a binder. Among these, those having a structure having two or more aromatic hydroxyl groups on the same aromatic ring and having a total of three or more hydroxyl groups are preferable.

As the diazoketone compounds, for example, 5
-Diazomeldrum acid, 2-diazo-1-phenylbutane-1,3-dione, 1,3-diphenyl-2-diazopropane-1,3-dione, 2-diazomethylphenylmalonate, 2-diazo- 1- (3'-chlorosulfonylphenyl) -1-trimethylsilylpropane-1,3
-Zeon or JP-A-60-14235, 62-
47296, 63-253938, 63-2539
40 diazoketone compounds and the like.

The azide compounds include, for example, 1-azidopyrene, p-azidobenzophenone, 4'-methoxy-4-azidodiphenylamine, 4-azidobenzal-
2'-methoxyacetophenone, 4-azido-4'-nitrophenylazobenzene, 1- (p-azidophenyl) -1-cyano-4- (p-diethylaminophenyl) -1,3-butadiene, 4- Monoazide compounds such as azidochalcone, 4,4′-diazidobenzophenone,
4,4'-diazidodiphenylmethane, 4,4'-diazidostilbene, 4,4'-diazidochalcone, 4,4 '
-Diazidobenzalacetone, 4,4'-diazidodiphenylsulfide, 4,4'-diazidodiphenylsulfide, 4,4'-diazidodiphenylsulfone, 2,6-
Di (4'-azido benzal) cyclohexanone, 2,
6-di (4'-azidobenzal) -4-methylcyclohexanone, 1,8-diazidonaphthalene, 3-azido-4 '-(3'-azidobenzamethyl) stilbene, or JP-B-35-49295, 4 8-318
41, 44-26047, 44-26048, 4
5-7328, 47-30204, 49-1228
3, 51-29932, 53-325, JP-A-48
-14316, 48-93623, 49-8110
3, 55-57538, 56-39538, 58
-68036, 58-203438, 60-107
644, 62-2249, 63-305347, U
SP2852379, 2940853, 30924
94, GB892281, FR151114, DE5
14057 and the like.

The ortho-nitrobenzyl compounds include:
For example, orthonitrobenzyl stearate, orthonitrobenzyl cholesteric acid, orthonitrobenzyloxytriphenylsilane, 5-methyl-2-nitrobenzyltriphenylsilane, di (5-chloro-2-nitrobenzyloxy) diphenylsilane,
Poly-ortho-nitrobenzyl methacrylate, poly-ortho-nitrobenzyl acrylate, ortho-nitrobenzaldehyde acetal of polyvinyl alcohol,
Or JP-A-48-47320 and JP-A-60-19853.
8, ortho-nitrobenzyl compounds described in JP-A-61-138255, JP-A-62-153853 and JP-B-56-2696.

Examples of the orthonitroarylsulfenyl ester compounds include 2,4-dinitrobenzenesulfenylcholate, orthonitrobenzenesulfenyladamantane carboxylate, orthonitrobenzenesulfenylyl tris (trimethylsilyl) cholate, polymethacrylate and the like. 2,4-dinitrobenzenesulfenyl methacrylate, JP-A-61-3141 and JP-A-61-36
Ortho nitroaryl sulfenyl ester compounds described in No. 741 and the like.

Examples of the polyolefin sulfon compounds include polybutene-1-sulfone, polyhexene-1-sulfone, polycyclopentene sulfone, poly-2-methylpentene sulfone, polyoctene-1-sulfone, polybutene-2-sulfone, and JP-A-62-27.
732, 63-218949 and the like.

The tetrahydropyranyl ether compounds include, for example, 4,4'-isopropylidenediphenol-bis-2-tetrahydropyranyl ether,
4'-Sulfonyldiphenol-bis-tetrahydropyranyl ether, poly-tetrahydropyranyl ether of phenol formaldehyde resin and US Pat.
778, and the like.

The content ratio of the mixture of the ionizing radiation compound (A) and the ionizing radiation compound (B) in the ionizing radiation compound of the present invention is such that the mixture is 30% of the ionizing radiation compound. % Or more, preferably 40%
That is all. It is particularly preferably at least 50%. When this ratio is 30% or less, the film thickness dependency is deteriorated, and the development residue tends to increase. The use ratio of the ionizing radiation-sensitive compound and the water-insoluble alkali-soluble resin in the present invention is 5 to 10 parts by weight per 100 parts by weight of the resin.
0 parts by weight, preferably 20 to 80 parts by weight. If the use ratio is less than 5 parts by weight, the residual film ratio is remarkably reduced, and if it exceeds 100 parts by weight, sensitivity and solubility in a solvent are reduced. When an ionizing radiation-sensitive acid generator compound is used, an acid labile group-containing alkali dissolution inhibitor compound 100 is used.
0.1 parts by weight of the ionizing radiation-sensitive acid generator compound was
It is used in an amount of from 200 to 200 parts by weight, preferably from 1 to 60 parts by weight. If this ratio is less than 0.1 part by weight, the sensitivity is significantly reduced.

In the present invention, a polyhydroxy compound can be further contained to promote dissolution in a developer.
Preferable polyhydroxy compounds include polyhydroxy aromatic compounds which are ester residues of the aforementioned quinonediazide compounds. Representative examples include phenols, resorcinol, phloroglucin, 2,3,4-
Trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, polyhydroxytriphenylmethanes, polyhydroxyspirobiindanes, hydroxybenzylphenol , Acetone-pyrogallol condensation resin, phloroglucid and the like.

Solvents for dissolving the ionizing radiation-sensitive compound, the water-insoluble alkali-soluble low molecular weight compound and the water-insoluble alkali-soluble resin of the present invention include ketones such as methyl ethyl ketone, methyl amyl ketone and cyclohexanone, ethylene glycol monomethyl ether, ethylene glycol and the like. Alcohol ethers such as glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, n-propyl alcohol, iso-butyl alcohol, n-butyl alcohol, cyclohexyl alcohol, diacetone alcohol;
Alcohols such as dioxane, ethers such as dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, methyl methoxypropionate, propyl formate, propyl acetate, butyl acetate, methyl propionate, methyl lactic acid Esters such as methyl, ethyl lactate, ethyl 2-hydroxy-2-methylpropionate, methoxyethyl propionate, methoxymethyl propionate, ethoxyethyl propionate, and ethyl pyruvate; propylene glycol; Propylene glyco-
Propylene glycols such as monomethyl ether, propylene glycol monoethyl ether and propylene glycol monomethyl ether acetate; halogenated hydrocarbons such as 1,1,2-trichloroethylene; and aromatics such as toluene and xylene. Hydrocarbons, dimethylacetamide, N-methylpyrrolidone, dimethylformamide,
Highly polar solvents such as dimethyl sulfoxide can be exemplified. These solvents can be used alone or as a mixture of a plurality of solvents.

The ionizing radiation-sensitive resin composition of the present invention includes:
If necessary, compatible additives such as a dye, a plasticizer, an adhesion aid storage stabilizer, a sensitizer, a striation inhibitor, and a surfactant can be added. Specific examples include dyes such as methyl violet, crystal violet, malachite green, curcumin, tinuvin, thiazolyl azophenol, stearic acid, acetal resins, phenoxy resins, plasticizers such as alkyd resins, and hexamethyl. Adhesion aids such as disilazane and chloromethylsilane; and polyoxyethylene ethers such as polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, and polyoxyethylene nonylphenyl ether.
Terbits, polyoxyethylene polyoxypropylene block copolymers, sorbitan monostearate, sorbitan fatty acid esters such as sorbitan trioleate, polyoxyethylene sorbitan monostearate,
Polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monopalmitate and polyoxyethylene sorbitan trioleate;
F301, EF303, EF352 (Shin-Akita Chemical Co., Ltd.)
), Megafac F171, F173 (Dainippon Ink Co., Ltd.), Florad FC430, FC431 (Sumitomo 3M Co., Ltd.), Asahi Guard AG710,
Freon S-382, SC101, SC102, SC10
3, fluorinated surfactants such as SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid-based or methacrylic acid-based (co) polymer-No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK). 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 water-insoluble alkali-soluble resin in the composition of the present invention. In particular, in the case of dyes, dyes containing an alkali-soluble group such as an aromatic hydroxyl group or a carboxylic acid group in the molecule, such as curcumin, are particularly advantageously used. It is desirable to adjust the amount of the low molecular weight dissolution promoter to match to obtain optimal performance.

The above-mentioned ionizing radiation-sensitive resin composition is applied on a substrate (eg, silicon / silicon dioxide coating) used for the production of precision integrated circuit devices by a suitable application method such as a spinner or a coater. A good resist pattern can be obtained by exposing through a mask and developing. The ionizing radiation-sensitive resin composition of the present invention,
A so-called positive pattern image in which a portion not normally irradiated with ionizing radiation is formed as an image is obtained. However, a method of performing a heat treatment in an amine atmosphere as disclosed in JP-A-63-316429, or a method described in JP-A-62-35350 and EP263434A.
6-di-t-butylpyridine, benzimidazole,
By compounding a compound such as pyridine, quinoline, acridine, lutidine, 1-methylbenzimidazole, melamine formaldehyde alkyl ether, etc., with the resin composition of the present invention, it is possible to perform a so-called image inversion and effectively obtain a negative pattern. is there.

Examples of the developer for the ionizing radiation-sensitive resin composition of the present invention include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, and the like.
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, and tetraamines Aqueous solutions of quaternary ammonium salts such as methylammonium hydroxide, tetraethylammonium hydroxide and choline hydroxide, and alkalis such as cyclic amines such as pyrrole and piperidine can be used. Further, an appropriate amount of an alcohol, a surfactant, an aromatic hydroxyl group-containing compound or the like may be added to the aqueous solution of the above alkalis. Among them, it is particularly preferable to use tetramethylammonium hydroxide. Hereinafter, the present invention will be described with reference to examples. However, it is needless to say that aspects of the present invention should not be limited to these examples.

[0111]

【Example】

Synthesis Example 1 Synthesis of Photosensitive Material [A-2A] In a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, 50.5 g of 2,6-bis (hydroxymethyl) -p-cresol and o-cresol 194. 7 g with methano-
And 9.1 g of 36% hydrochloric acid was added. Thereafter, the reaction was carried out for 7 hours under reflux. The reaction mixture was poured into 4 l of water, and the precipitate was washed with water.
Stir in dichloromethane (2/1) to remove unreacted raw materials. Recrystallization from ethanol / water yielded 54 g of a white solid. According to NMR, this was 2,6-bis (3′-methyl-4′-hydroxybenzyl) -p-
It was confirmed to be cresol. 8.71 g of 2,6-bis (3′-methyl-4′-hydroxybenzyl) -p-cresol obtained in a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping device, and 1, 2-Naphthoquinonediazide-5-sulfonyl chloride 13.4
3 g, acetone 200 ml and distilled water 10 ml were charged and dissolved. To this, a solution of 5.27 g of triethylamine in 25 ml of acetone was added dropwise at room temperature over 35 minutes, and the mixture was further reacted for 3 hours. After adding 3.14 g of acetic acid to the reaction mixture, it was poured into 3 l of distilled water. The precipitated yellow precipitate was separated by filtration, washed with water and dried to obtain a photosensitive material [A-2A] 1
9.7 g were obtained. Analysis by high performance liquid chromatography revealed that the diester compound was 59% and the triester compound was 2%.
4%.

Synthesis Example 2 Synthesis of Photosensitive Material [A-2B] Instead of 8.71 g of 2,6-bis (3′-methyl-4′-hydroxybenzyl) -p-cresol, 2,6-bis (3 ′) was used. -Methyl-4'-hydroxybenzyl) -p-
17.1 g of photosensitive material [A-2B] was obtained in the same manner as in Synthesis Example 1 except that 5.81 g of cresol was used. Analysis by high performance liquid chromatography revealed that the diester form was 2
0% and triesters were 75%.

Synthesis Example 3 Synthesis of Photosensitive Material [A-3A] In a three-necked flask equipped with a stirrer, a reflux condenser and a thermometer, 40.4 g of 2,6-bis (hydroxymethyl) -p-cresol was added. 176 g of 5-xylenol was dissolved in 170 ml of methanol, and 7.3 g of 36% hydrochloric acid was added. Thereafter, the reaction was carried out for 12 hours under heating and reflux. The reaction mixture was poured into 3.5 l of water, and the precipitate was washed with water and further stirred in hexane / dichloromethane (2/1) to remove unreacted raw materials. By recrystallizing with ethanol / water, 41 g of a white solid was obtained. By NMR, this is 2,
It was confirmed to be 6-bis (2 ′, 5′-dimethyl-4′-hydroxybenzyl) -p-cresol. 6. 6,6-bis (2 ', 5'-dimethyl-4'-hydroxybenzyl) -p-cresol obtained in a four-necked flask equipped with a stirrer, reflux condenser, thermometer and dropping device.
34 g, 10.48 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride, 160 ml of acetone and 10 mL of distilled water were charged and dissolved. To this, a solution of 4.11 g of triethylamine in 20 ml of acetone was added dropwise at room temperature over 30 minutes, and then the mixture was further reacted for 5 hours. After adding 2.45 g of acetic acid to the reaction mixture, it was poured into 2.5 l of distilled water. The deposited yellow precipitate was separated by filtration, washed with water and dried to obtain 15.5 g of a photosensitive material [A-3A]. Analysis by high performance liquid chromatography revealed that the diester form was 61%.
%, And the triester form was 35%.

Synthesis Example 4 Synthesis of Photosensitive Material [A-3B] 2,6-bis (2 ′, 5′-dimethyl-4′-hydroxybenzyl) -p-cresol Instead of 7.34 g, 2,6-bis 13.2 g of photosensitive material [A-3B] in the same manner as in Synthesis Example 3 except that 4.91 g of (2 ′, 5′-dimethyl-4′-hydroxybenzyl) -p-cresol was used.
I got Analysis by high performance liquid chromatography revealed that the diester form was 18% and the triester form was 77%.

Synthesis Example 5 Synthesis of Photosensitive Material [A-71A] A flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping device, and a gas inlet tube was prepared as follows.
6 g of phenol and 2.5 g of a 16% aqueous solution of methyl mercaptan sodium salt were added thereto, and the mixture was saturated by introducing hydrogen chloride gas while stirring at 40 ° C. Subsequently, a mixture of 19 g of p-isopropenylacetophenone and 19 g of phenol was added dropwise over 2 hours while introducing hydrogen chloride gas at 40 ° C. The reaction was carried out at 40 ° C. for 6 hours while introducing hydrogen chloride gas little by little. After the temperature was lowered to room temperature and allowed to stand overnight, 700 g of toluene and 360 g of a 3% aqueous sodium hydrogen carbonate solution were added, and the mixture was vigorously stirred at 80 ° C. for 30 minutes. After cooling to room temperature, the precipitated crystals were collected by filtration and washed with toluene and distilled water. Methyl isobutyl ketone
After heating and dissolving in a toluene mixed solvent, washing with distilled water, cooling, the crystals were collected by filtration and dried to obtain 41 g of white crystals having a melting point of 221-224 ° C. As a result of mass spectrometry, M ⁺ was 424. 16.99 g of white crystals obtained in a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a dropping device, 21.49 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride, 320 ml of acetone, 15 m of distilled water
L was charged and dissolved. To this, triethylamine 8.4
A solution of 3 g of acetone in 40 ml was added dropwise at room temperature over 30 minutes, and the reaction was further continued for 4 hours. After adding 5.02 g of acetic acid to the reaction mixture, it was added to 4.8 l of distilled water.
The deposited yellow precipitate was separated by filtration, washed with water and dried to obtain 32.7 g of a photosensitive material [A-71A]. Analysis by high performance liquid chromatography revealed that the diester form was 68% and the triester form was 29%.

Synthesis Example 6 Synthesis of Photosensitive Material [A-71B] 11.33 g of white crystals instead of 16.99 g of white crystals
Except for using a photosensitive material [A-71]
B] 26.4 g were obtained. As a result of analysis by high performance liquid chromatography, the diester form was 10% and the triester form was 87%.

Synthesis Example 7 Synthesis of Photosensitive Material [A-9A] 15 g of 2,6-bis (3,5-dimethyl-4-hydroxybenzyl) p-cresol, 1,2-naphthoquinonediazide-5-sulfonyl chloride 3 g and 300 ml of acetone were charged into a three-necked flask and uniformly dissolved. Then, triethylamine / acetone = 12.4 g /
30 ml of the mixture was gradually added dropwise, and reacted at 25 ° C. for 15 hours. The reaction mixture was poured into 1500 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was separated by filtration, washed with water and methanol, and dried (40 ° C.) to recover a photosensitive material [A-9A]. When the product was analyzed by HPLC, it was a mixture composed of 28% of a triester compound, 59% of a diester compound, and the rest of other low-substituted compounds.

Synthesis Example 8 Synthesis of Photosensitive Material [A-9B] 10 g of 2,6-bis (3,5-dimethyl-4-hydroxybenzyl) p-cresol, 1,2-naphthoquinonediazide-5-sulfonyl chloride 3 g and 300 ml of acetone were charged into a three-necked flask and uniformly dissolved. Then, triethylamine / acetone = 12.4 g /
30 ml of the mixture was gradually added dropwise, and reacted at 25 ° C. for 15 hours. The reaction mixture was poured into 1500 ml of a 1% aqueous hydrochloric acid solution, and the resulting precipitate was separated by filtration, washed with water and methanol, and dried (40 ° C.) to recover a photosensitive material [A-9B]. When the product was analyzed by HPLC, it was a mixture comprising 78% of the triester compound, 12% of the diester compound, and the balance of other low-substituted compounds.

Hereinafter, a production example of the novolak resin according to the present invention will be described. Reference Example 1 Synthesis of novolak resin (a) 50 g of m-cresol, 50 g of p-cresol, 37%
45.5 g of formalin aqueous solution and oxalic acid dihydrate 0.0
5 g was charged into a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, and heated to 100 ° C. while stirring.
The reaction was performed for 10 hours. After the reaction, the mixture was cooled to room temperature, the reflux condenser was removed, and the pressure was reduced to 25 mmHg. Then gradually 1
The temperature was raised to 60 ° C. to remove water and unreacted monomers,
3 g of novolak resin (a) was obtained. When this was analyzed by GPC, the Mw was 6540 and the degree of dispersion was 7.4.

Reference Example 2 Synthesis of Novolak Resin (b) 44 g of the novolak resin (a) was dissolved in 400 ml of MEK, and then 1600 ml of cyclohexane was added, followed by heating to 60 ° C. with stirring. This solution was allowed to stand still at room temperature and left for 16 hours to obtain a precipitate.
The precipitate was recovered, filtered and dried in a vacuum oven at 50 ° C. to obtain about 15 g of novolak resin (b). This is GP
When analyzed by C, the Mw was 8720 and the degree of dispersion was 4.3.

Reference Example 3 Synthesis of novolak resin (c) 456.6 g of m-cresol, 295.p-cresol.
8 g and 404.35 g of 37% formalin aqueous solution were charged into a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, and stirred while heating in a 110 ° C. oil bath. When the internal temperature reached 90 ° C., 1.03 g of oxalic acid dihydrate was added. Thereafter, the reaction was continued under reflux for 15 hours, the temperature of the oil bath was further raised to 200 ° C., and water and unreacted monomers were removed under reduced pressure except for the reflux condenser to obtain 565 g of novolak resin (c). When analyzed by GPC, Mw
Was 8860 and the degree of dispersion was 7.7.

Reference Example 4 Synthesis of Novolak Resin (d) 44 g of the novolak resin (c) was dissolved in 280 ml of acetone and 175 ml of toluene.
0 ml of hexane was added, and the mixture was heated to 40 ° C. while stirring. The solution was allowed to stand at room temperature for 16 hours to obtain a precipitate. The precipitate was recovered, filtered and dried in a vacuum oven at 50 ° C. to obtain about 15 g of novolak resin (d). When this was analyzed by GPC, Mw was 11400,
The dispersity was 3.9.

Reference Example 5 Synthesis of Novolak Resin (e) 50 g of m-cresol and 25 g of p-cresol 25 were placed in a 500-ml three-necked flask equipped with a stirrer and a reflux condenser.
g, 2,5-xylenol 28 g, formalin (37
% Aqueous solution), stirred well while heating in an oil bath at 110 ° C., added 0.15 g of oxalic acid, and heated and stirred for 15 hours. Then raise the temperature to 200 ° C and gradually
Distillation was performed for 2 hours under reduced pressure to 2 mmHg to remove unreacted monomers, water, formaldehyde, oxalic acid and the like. The temperature was lowered to room temperature to obtain 81 g of novolak resin (e). When this was analyzed by GPC, the Mw was 4,400 and the degree of dispersion was 6.5.

Reference Example 6 Synthesis of novolak resin (f) 20 g of novolak resin (e) was dissolved in 60 g of methanol. To this, 30 g of distilled water was gradually added with stirring to precipitate the resin component. The upper layer separated into two layers was removed by decanting. Then, 30 g of methanol was added and dissolved therein, and 40 g of distilled water was gradually added again with stirring to precipitate a resin component. The separated upper layer was removed by decantation, and the recovered resin component was heated to 40 ° C. in a vacuum drier to obtain 2
After drying for 4 hours, 7 g of novolak resin (f) was obtained. GP
When analyzed by C, the Mw was 9860 and the degree of dispersion was 2.8.
It was 0.

Reference Example 7 Synthesis of novolak resin (g) Methylene bis-p-cresol 14.4 g, o-cresol 2.2 g, 2,3-dimethylphenol 70.2
g, 2,3,5-trimethylphenol 27.2 g,
9.77 g of 2,6-dimethylphenol was mixed with 50 g of diethylene glycol monomethyl ether, and charged into a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer. Then, 85.2% 37% aqueous formalin solution
g was added and stirred while heating in a 110 ° C. oil bath. When the internal temperature reached 90 ° C., 6.2 g of oxalic acid dihydrate was added. After that, the reaction was continued for 18 hours while maintaining the temperature of the oil bath at 130 ° C., and then the reflux condenser was removed to remove the oil at 200 ° C.
To remove unreacted monomers. The obtained novolak resin had a Mw of 3530 and a dispersity of 2.25.

Reference Example 8 Synthesis of Novolak Resin (h) 8.1 g of p-cresol, 6.6 g of o-cresol,
119.1 g of 2,3-dimethylphenol, 2,3,5
40.8 g of trimethylphenol and 11 g of 2,6-dimethylphenol were mixed with 73.5 g of diethylene glycol monomethyl ether, and charged in a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer. Then
133.8 g of 37% formalin aqueous solution was added, and 110
The mixture was stirred while being heated in an oil bath at 0 ° C. When the internal temperature reached 90 ° C., 9.3 g of oxalic acid dihydrate was added. Thereafter, the reaction was continued while keeping the temperature of the oil bath at 130 ° C. for 18 hours, and then the reflux condenser was removed, followed by vacuum distillation at 200 ° C. to remove unreacted monomers. The obtained novolak resin had a Mw of 3830 and a dispersity of 2.36.

Reference Example 9 Synthesis of Photosensitive Material (A) 2,3,4,4'-Tetrahydroxybenzophenone 1
0 g, 41 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 400 ml of γ-butyrolactone were charged into a three-necked flask and uniformly dissolved. Next, a mixed solution of triethylamine / acetone = 17 g / 40 ml was gradually added dropwise, and reacted at 25 ° C. for 3 hours. 1% reaction mixture
The mixture was poured into 1,000 ml of an aqueous hydrochloric acid solution, and the resulting precipitate was separated by filtration, washed with water and methanol, and dried (40 ° C.) to recover a photosensitive material (A). When the product was analyzed by high performance liquid chromatography (HPLC),
As seen from the peak area ratio on the chart detected by the absorbance of the tetraester compound, 81% and the triester compound were 5%.
%, The remainder being a mixture of other low-substituted products.

Reference Example 10 Synthesis of Photosensitive Material (B) 3,3,3 ', 3'-Tetramethyl-1,1'-spirobiindane-5,6,7,5', 6 ', 7'-hexol 1
0 g, 1,2-naphthoquinonediazide-5-sulfonyl chloride (32.5 g) and acetone (500 ml) were charged into a three-necked flask and uniformly dissolved. Next, a mixed solution of triethylamine / acetone = 13.7 g / 50 ml was gradually added dropwise, and reacted at 25 ° C. for 3 hours. 1% reaction mixture
The resulting precipitate was separated by filtration, washed with water and methanol, and dried (40 ° C.) to recover a photosensitive material (B). When the product was analyzed by HPLC,
The mixture was composed of 86% of the hexaester compound and the remainder of other low-substituted compounds.

Reference Example 11 Synthesis of Photosensitive Material (C) 2,6-bis (2,3,4-trihydroxybenzyl)
10 g of p-cresol, 50.4 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 500 ml of γ-butyrolactone were charged into a three-necked flask and uniformly dissolved. Then triethylamine / acetone = 20.7
g / 30 ml of the mixed solution was gradually added dropwise, and reacted at 20 ° C. for 10 hours. The reaction mixture was treated with a 1% hydrochloric acid aqueous solution at 1500 m.
The resulting precipitate was separated by filtration, washed with water and methanol, and dried (40 ° C.) to recover a photosensitive material (C). When the product was analyzed by HPLC, it was a mixture consisting of 25% of a heptaester compound, 58% of a hexaester compound and the rest of other low-substituted compounds.

The ionizing ionizing compound of the present invention formulated using the novolak resin prepared in the above reference example and the ionizing radiation-sensitive compound defined in the present invention in combination with a predetermined low molecular weight compound will be described below. The example of a radiation resin composition and the comparative example of the resist for a comparison are shown.

Examples 1 to 53 and Comparative Examples 1 to 35 Novolak resins (a) to (h) obtained in Reference Examples 1 to 8 described above.
And the photosensitive materials (A) to (C) obtained in Reference Examples 9 to 11,
Further, the ionizing radiation-sensitive compound (A), the ionizing radiation-sensitive compound (B) and the low molecular weight compound specified in the present invention are mixed in the types and amounts shown in Tables 1 and 2, and this is mixed with ethyl lactate 18
g and 4.5 g of ethoxyethyl propionate,
The solution was filtered using a 0.1 μm microfilter to prepare an ionizing radiation-sensitive resin composition. Here, the compositions of the diesters and triesters of naphthoquinonediazide-5-sulfonic acid of the ionizing radiation-sensitive compounds (A) and (B) in Tables 1 and 2 are the content values shown in Table 3. . The ionizing radiation-sensitive resin composition is applied to a silicon wafer using a spinner, and 90
After drying at 60 ° C. for 60 seconds, a resist film having a thickness of 0.98 μm was obtained. A reduced projection exposure system (Nikon NSR
After exposing using -2005i9C), the film was heated on a vacuum adsorption hot plate at 110 ° C. for 90 seconds, developed with a 2.38% aqueous solution of tetramethylammonium hydroxide for 1 minute, washed with water for 30 seconds, and dried.

The resist pattern of the thus obtained silicon wafer was observed with a scanning electron microscope to evaluate the ionizing radiation-sensitive resin composition. The results are shown in Tables 1 and 2. The sensitivity was defined as an exposure amount for reproducing a 0.5 μm mask pattern. In order to evaluate the development latitude, the same evaluation was performed by changing the development time between 40 seconds and 90 seconds. The ratio of the sensitivities defined above in both cases was used as an index of development latitude. The closer this value is to 1.0, the wider the development latitude and the more desirable the result. The resolving power indicates a limit resolving power at an exposure amount for reproducing a 0.5 μm mask pattern. In order to evaluate the film thickness dependence, the film thickness was set to 1.
A silicon wafer coated to a thickness of 00 μm was exposed and developed in the same manner. The ratio of the resolving power between the film having a thickness of 0.98 μm and the film having a thickness of 1.00 μm was used as an index of the film thickness dependency. The closer this ratio is to 1.0, the less the film thickness dependence is, which is a desirable result. The evaluation of the development residue was observed with a scanning electron microscope, and those in which the development residue was observed between the resist patterns were represented by x, and those in which the development residue was not observed were represented by o.

[0133]

[Table 1]

[0134]

[Table 2]

[0135]

[Table 3]

[0136]

[Table 4]

[0137]

[Table 5]

[0138]

[Table 6]

[0139]

[Table 7]

As described above, a resist sample satisfying the requirements of the present invention exhibits a high resolving power with a small dependency on film thickness and a small amount of development residues, and all of the samples exhibit excellent development latitude as compared with the resist of the comparative example. I understand.

[0141]

The ionizing radiation-sensitive resin composition of the present invention is characterized in that it has excellent film thickness dependence, has a small development residue, has a high resolution, and has a wide development latitude.
Therefore, it is most suitably used for mass production of semiconductor devices having ultrafine circuits.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-32352 (JP, A) JP-A-2-19846 (JP, A) JP-A-5-323597 (JP, A) JP-A-2-32 222954 (JP, A) JP-A-5-119475 (JP, A) JP-A-5-34917 (JP, A) JP-A-2-220056 (JP, A) JP-A-2-103543 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03F ^7/ 00-7/42

Claims (5)

(57) [Claims] 1. An ionizing radiation-sensitive resin composition containing a water-insoluble alkali-soluble resin, a water-insoluble alkali-soluble low-molecular compound and an ionizing radiation-sensitive compound, wherein the ionizing radiation-sensitive compound is represented by the following general formula: (A1) or (A
A naphthoquinonediazidosulfonic acid diester compound (A), which is a water-insoluble alkali-soluble low-molecular compound having three phenolic hydroxyl groups represented by 2), and a compound represented by the following general formula:
A mixture of a water-insoluble alkali-soluble low molecular weight compound having four phenolic hydroxyl groups , represented by (B1) or (B2), and a naphthoquinonediazidosulfonic acid diester compound (B) is used as the ionizing radiation-sensitive compound. 30%
An ionizing radiation-sensitive resin composition comprising the above. Embedded image Here, R _{1 to} R ₈ and R _{20 to} R ₂₄ each represent a hydrogen atom,
It represents a - single bond, a carbonyl group, a sulfide group, a sulfonyl group or _{-C (R b1) (R b2} ): CN, -X-R a1 or a halogen atom, X ₁ to X _2.
However, when l = 0, X ₁ is a group represented by the following general formula A ₁₁ or A _12; X ₃ : a group represented by the following general formula A ₂₁ or A ₂₂ R ₉ , R _{12 to} R ₁₇ , R _{25 to} R ₃₁ , R _b1 and R _b2 : a hydrogen atom, a methyl group, an ethyl group or a haloalkyl group having 1 to 2 carbon atoms, R _b1 and R _b2 , R ₂₅ and R ₂₆ , R ₂₈ and R ₂₉ and R ₃₀ and R ₃₁ may be bonded together to form an alicyclic hydrocarbon residue. R ₁₀ , R ₁₁ , R _a3 , R _a4 , R ₁₈ , R ₁₉ : a hydrogen atom, -XR _a1 , -CN or a halogen atom, X: a single bond, -O-, -S-, -CO- , -OC (=
O)-or N (R _a1 ) CO-, Xa: carbonyl group, sulfide group, sulfonyl group or -C (R _b1 ) (R _b2 )-, R _a1 : alkyl group having 1 to 10 carbon atoms, aryl A group or an aralkyl group; Z ₁ : a single bond or a trivalent alicyclic hydrocarbon group formed together with CR ₉ ; Z ₂ : a single bond or —O—, k, l: 0 or 1, m, n: each 1 or 2, q: 1 to 8 integers, r, s: respectively 1 or 2, provided that _{r + s = 3, D 1} ~D 7: each a hydrogen atom, naphthoquinonediazide -
Represents a 4 (and / or 5) -sulfonyl group. R ₃₂ ~R _46, R _49: each a hydrogen atom, -CN, -X-
R _a1 or a halogen atom, R ₄₇ : a hydrogen atom, a methyl group, an ethyl group, a haloalkyl group having 1 to 2 carbon atoms, or R _c , wherein R _c is a group represented by the following general formula B ₂₁ ; Formula 4 R _48: a hydrogen atom, a methyl group, an ethyl group, a haloalkyl group having 1 to 2 carbon atoms or R _d, where, R _d is a group represented by the following general formula B _22, embedded image R ₅₀ , R ₅₁ : a hydrogen atom, —CN, —X—R _a1 or a halogen atom, provided that when R ₄₇ ≠ R _c and R ₄₈ ≠ R _d , each represents R _c ; X _{4 to} X ₆ : single bond, a carbonyl group, a sulfide group, a sulfonyl group or _{-C, (R b1) (R} b2) -, X 7, X 8: single bond or _{- (CR 60 R 61) u} (CH =
CH) _v - group represented by, R ₅₂ to R _59: each a hydrogen atom, -CN, -X-R _a1 or a halogen atom, R _60, R _61: respectively a hydrogen atom, a methyl group, an ethyl group or a carbon number A haloalkyl group of 1 to 2, Z ₃ : a tetravalent alkyl group residue having 1 to 6 carbon atoms, D _{8 to} D ₁₆ : a hydrogen atom, naphthoquinonediazide-4 (and / or 5) -sulfonyl group, t: U, x: an integer of 0 or 1 to 8, y, v, w: 0 or 1, respectively, provided that R ₄₇ ≠ R _c and R ₅₀ ≠ R _c and R ₅₁ ≠ R _c , Y = 1 and w = 1,
Otherwise, y = 0. However, for D _{1 to} D ₁₆ , general formula (A1),
In each of the ionizing radiation-sensitive compounds represented by (A2), (B1) or (B2), two per molecule are a naphthoquinonediazide-4 (and / or 5) -sulfonyl group. 2. The method according to claim 1, wherein the water-insoluble alkali-soluble resin is phenol, cresol, xylenol,
An ionizing radiation-sensitive resin composition comprising at least one novolak resin synthesized by a condensation reaction of trimethylphenol or a mixture of two or more thereof with an aldehyde compound. 3. The method according to claim 1, wherein the water-insoluble alkali-soluble resin is p-cresol, o-cresol, 2,3,
-Ionizing radiation-sensitive resin composition characterized in that it is at least one novolak resin synthesized by a condensation reaction of a mixture of xylenol, 2,6-xylenol, and trimethylphenol with an aldehyde compound. . 4. The method according to claim 1, wherein the water-insoluble alkali-soluble low molecular weight compound has a phenolic hydroxyl group and an aromatic ring, and the ratio of the phenolic hydroxyl group to the aromatic ring is 0.5 to 0.5.
An ionizing radiation-sensitive resin composition, which is at least one compound of 1.4. 5. The method according to claim 1, wherein the ratio of the ionizing radiation-sensitive compound (A) to the ionizing radiation-sensitive compound (B) is 0.1.
An ionizing radiation-sensitive resin composition, which is 1 to 5.