JPH07248620A - Positive type resist composition - Google Patents

Abstract

PURPOSE:To provide a positive type resist composition excellent in the balance of characteristics such as resolution, profile, and sensitivity. CONSTITUTION:This positive type resist composition is constituted of an alkali- soluble resin and a quinone diazide photosensitive agent containing at least one kind of quinone diazide sulfonate within the phenol compounds expressed by formulas I, II, where Z1-Z12 in the formulas I, II independently indicate groups expressed by formula III, R1-R3 in the formula III indicate hydrogen, an alkyl, or cycloalkyl group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist composition which is sensitive to radiation such as ultraviolet rays, deep ultraviolet rays including excimer laser, electron rays, ion beams and X-rays.

[0002]

2. Description of the Related Art In recent years, integrated circuits have become finer with higher integration, and submicron pattern formation is required. As a result, there is a need for a positive resist composition having a better profile, sensitivity, resolution and the like. In particular, in the fabrication of 16 to 64M DRAM, it is necessary to resolve a pattern having a line width of 0.5 μm or less without a development residue (scum) and with a good profile. Generally, a method of increasing the amount of the photosensitizer is adopted to increase the resolution. However, when the amount of the photosensitizer in the composition is increased, the resolution is increased, but on the other hand, there are problems that scum occurs and the profile deteriorates.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and provides a positive resist composition which is excellent in balance of various performances such as resolution, profile and sensitivity and has no scum. .

[0004]

The present invention has the general formula (I
a) and (Ib)

[0005]

[Chemical 3]

[Wherein Z _{1 to} Z ₁₂ are independently the following formulas:

[0007]

[Chemical 4]

(In the formula, each of R _{1 to} R ₃ independently represents hydrogen or a halogen atom, —OCOR ₄ or optionally substituted cycloalkyl, alkyl or alkoxy group, and R ₄ may be substituted. Represents a good cycloalkyl, alkyl or phenyl group). ] A positive resist composition comprising a quinonediazide sensitizer containing at least one quinonediazide sulfonic acid ester among the phenol compounds represented by the above and an alkali-soluble resin.

The optionally substituted alkyl group represented by R _{1 to} R ₄ and the optionally substituted alkoxy group represented by R _{1 to} R ₃ are preferably linear or branched C 1-6. The following are listed. R _{1 to} R ₄
Examples of the optionally substituted cycloalkyl represented by are those having 5 to 10 carbon atoms. Preferred Z _{1 to} Z ₁₂ in formulas (Ia) and (Ib) are, for example,

[0010]

[Chemical 5]

[0011]

[Chemical 6]

And the like.

Phenolic compounds represented by the general formulas (Ia) and (Ib) are, for example, compounds represented by the formulas (IIa) and (IIb).

[0014]

[Chemical 7]

Each of the methylol compounds represented by

[0016]

[Chemical 8]

(Wherein R _{1 to} R ₃ have the same meanings as described above), and can be produced by reacting in the presence of an acid catalyst such as p-toluenesulfonic acid or sulfuric acid. it can.

The quinonediazide sulfonic acid ester of the phenol compound represented by the general formulas (Ia) and (Ib) can be prepared by a known method, for example, the phenol compound represented by the general formulas (Ia) and (Ib) and 1,2-naphthoquinonediazide sulfone. It can be produced by reacting an acid halide or a 1,2-benzoquinonediazide sulfonic acid halide in the presence of a weak alkali. The amount of the quinonediazide-based photosensitizer used is usually 5 to 50% by weight, preferably 10 to 40% by weight, based on the total solid content of the positive resist composition.

The alkali-soluble resin is obtained by addition-condensing phenols and aldehydes. Examples of phenols include phenol, o-, m- or p-cresol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol, 2,3,5-trimethylphenol, 4-t-butylphenol. , 2-t-butylphenol, 3-t-butylphenol, 3-ethylphenol, 2-ethylphenol, 4-ethylphenol, 3-methyl-6-t-butylphenol, 4-methyl-2-t-butylphenol, 2- Naphthol 1,
3-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, or general formula (III)

[0020]

[Chemical 9]

(Wherein R _{5 to} R ₇ each independently represent a hydrogen atom or an alkyl or alkoxy group having 1 to 4 carbon atoms, and k represents 1 or 2), or Two or more and general formula (IV)

[0022]

[Chemical 10]

(In the formula, R _{8 to} R ₁₃ each independently represent a hydrogen atom or an alkyl or alkoxy group having 1 to 4 carbon atoms, and R ₁₄ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an aryl group. Each of a to c represents 0, 1 or 2, and a + b + c> 2.
Seed or a mixture of two or more kinds. These phenols may be used alone or in combination of two or more.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylaldehyde, α- or β-phenylpropylaldehyde,
o-, m- or p-hydroxybenzaldehyde,
Examples thereof include glutaraldehyde, glyoxal, o- or p-methylbenzaldehyde, and the like. The addition condensation of phenols and aldehydes is carried out by a conventional method in the presence of a catalyst, and the reaction conditions are usually 60 to 250 ° C. and 2 to 30 hours. Examples of the catalyst include organic acids (oxalic acid, formic acid, trichloroacetic acid, p-toluenesulfonic acid, etc.), inorganic acids (hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid, etc.) or divalent metal salts (zinc acetate, magnesium acetate, etc.) Etc. The addition condensation is carried out in bulk or in a suitable solvent. The weight average molecular weight in terms of polystyrene of the alkali-soluble resin obtained by addition condensation is 2000 to 50000.

From the viewpoint of resolution, heat resistance and scum, the alkali-soluble resin obtained by addition condensation is subjected to, for example, an operation such as fractionation to obtain a component G having a molecular weight of 1000 or less in terms of polystyrene.
The pattern area by PC (UV-254 nm, the same applies hereinafter) is preferably 25% or less, more preferably the total pattern area excluding the pattern area of unreacted phenols.
20% or less, particularly preferably 15% or less. For fractionation, alkali-soluble resin obtained by addition condensation is used as a good solvent such as alcohol (methanol or ethanol), ketone (acetone, methyl ethyl ketone or methyl isobutyl ketone), ethylene glycol and its ethers, ether esters (ethyl cellosolve acetate etc.) ) Or tetrahydrofuran, and then pouring the obtained solution into water for precipitation, or pouring into a solvent such as pentane, hexane, heptane, or cyclohexane for liquid separation. The weight average molecular weight of the alkali-soluble resin after fractionation is preferably 3000 to 20000. The preferred addition amount of the alkali-soluble resin is 60 to 90% by weight based on the total solid content in the positive resist composition. Further, the positive resist composition includes, for example, a sensitizer, a compound represented by the general formula (IV), another resin, a surfactant, a stabilizer, or a dye for making the formed image more visible. Various additives can be added.

The solvent used for preparing the positive resist solution is preferably one which has an appropriate drying rate and which evaporates the solvent to give a uniform and smooth coating film. As such a solvent,
For example, glycol ether esters such as ethyl cellosolve acetate and propylene glycol monomethyl ether acetate, solvents described in JP-A-2-220056, esters such as ethyl pyruvate, n-amyl acetate and ethyl lactate, 2-heptanone, γ- Examples include ketones such as butyrolactone. These solvents may be used alone or in 2
Used as a mixture of two or more species. The amount of the solvent is not particularly limited as long as it can be applied on the wafer so as to form a coating film that is homogeneous and has no pinholes or uneven coating, but it is usually solid (that is, quinonediazide-based photosensitizer, alkali-soluble resin and various types of resins). A positive resist solution is prepared so that the additive) is 3 to 50% by weight.

[0027]

The positive resist composition of the present invention has an excellent balance of various performances such as resolution, profile and sensitivity required as a resist, and has no scum.

[0028]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, “part” means “part by weight”.

Synthesis Example 1 TPPA1000-P manufactured by Honshu Kagaku Co., Ltd. [Compound in which Z _{1 to} Z ₆ in the general formula (Ia) are all p-hydroxybenzyl groups] 16 g, 1,2-naphthoquinonediazide-5-sulfone In a mixture of 16.2 g of acid chloride and 161 g of dioxane,
Triethylamine (7.32 g) was added dropwise at 20 to 30 ° C. for 1 hour. After completion of dropping, react at 30 ° C for 15 hours, and then add acetic acid 1.82
After adding g, the mixture was stirred at the same temperature for 1 hour. After the reaction mixture was filtered and washed (dioxane), the filtrate was added to 5.32 g of acetic acid and 532 g of ion-exchanged water and stirred, and the precipitated crystals were filtered. After washing the obtained cake with 532 g of deionized water, 40
Photosensitizer A was obtained by drying at ° C. Synthesis Example 2 TPPA1100-2C manufactured by Honshu Kagaku Co., Ltd. [Compound in which Z _{1 to} Z ₆ in the general formula (Ia) are all 3-methyl-4-hydroxybenzyl groups] 16 g, 1,2-naphthoquinonediazide-5 6.79 g of triethylamine was added dropwise to a mixture of 15 g of sulfonic acid chloride and 155 g of dioxane at 20 to 30 ° C. for 1 hour. After completion of dropping, the mixture was reacted at 30 ° C. for 15 hours, 1.68 g of acetic acid was added, and the mixture was stirred at the same temperature for 1 hour. The reaction mixture is filtered and washed (dioxane), and the filtrate is washed with acetic acid.
5.1 g and ion-exchanged water (510 g) were added and the mixture was stirred, and the precipitated crystals were filtered. The obtained cake was washed with 510 g of ion-exchanged water and then dried at 40 ° C. to obtain a photosensitizer B. Synthetic Example 3 TPPA1200-26X manufactured by Honshu Kagaku Co., Ltd. [a compound in which Z _{1 to} Z ₆ are all 3,5-dimethyl-4-hydroxybenzyl groups in the general formula (Ia)] 16 g, 1,2-naphthoquinonediazide 14 g of 5-sulfonic acid chloride and dioxane
In a mixture of 150 g, 6.32 g of triethylamine at 20-30 ° C
-Drip in 1 hour. After completion of dropping, the mixture was reacted at 30 ° C. for 15 hours, 1.56 g of acetic acid was added, and the mixture was stirred at the same temperature for 1 hour. After the reaction mixture was filtered and washed (dioxane), the filtrate was added to 4.9 g of acetic acid and 492 g of ion-exchanged water and stirred, and the precipitated crystals were filtered. The resulting cake is deionized water
After washing with 492 g, it was dried at 40 ° C. to obtain a photosensitizer C.

Examples (Example Nos. 1 to 3) Alkali-soluble resins (abbreviated as resins in the table), quinonediazide-based photosensitizers (abbreviated as photosensitizers in the table) and additives having the compositions shown in the table below, It was mixed with 50 parts of 2-heptanone. The mixed solution was filtered through a Teflon filter having a pore size of 0.2 μm to prepare a resist solution. A silicon wafer washed by a conventional method is coated with the above resist solution using a spin coater.
It was applied to a thickness of 1.1 μm and baked on a hot plate at 90 ° C. for 1 minute. Next, a reduction projection exposure machine with an exposure wavelength of 365 nm (i-line) (Nikon product, NSR1755i7A NA = 0.5)
Was used to change the amount of exposure in steps. Then, the wafer was baked on a hot plate at 110 ° C. for 1 minute. This was developed with SOPD [developer; product of Sumitomo Chemical Co., Ltd.] for 1 minute to obtain a positive pattern. The resolution is 0.
The dimension of the line-and-space pattern that was separated without film loss was evaluated by a scanning electron microscope at an exposure amount (effective sensitivity) at which the 5 μm line-and-space pattern became 1: 1. As for the profile, the cross-sectional shape of the 0.5 μm line-and-space pattern at the effective sensitivity was observed with a scanning electron microscope.

[0031]

[Table 1]

Resin: m-cresol / p-cresol =
Novolak resin obtained by reacting under reflux with an oxalic acid catalyst at a molar ratio of 70/30, cresols / formalin = 1 / 0.8 [for the total pattern area excluding the pattern area of unreacted phenols in the GPC pattern] Molecular weight 60
Alkali-soluble resin having an area ratio of 00 or less of 34%, an area ratio of molecular weight of 1000 or less of 15%, and a weight average molecular weight of 8000 (both molecular weights are in terms of polystyrene).

Additive: A compound represented by the following formula.

[0034]

[Chemical 11]

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[Procedure amendment]

[Submission date] May 27, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

[0029] [Compound Z ₁ to Z ₆ is whole and hydroxycarboxylic benzyl group in the general formula (Ia)] Synthesis Example 1 Honshu Chemical Co., Ltd. TPPA1000-P
To a mixture of 16 g, 1,2-naphthoquinonediazide-5-sulfonic acid chloride 16.2 g and dioxane 161 g, triethylamine 7.32 g was added dropwise at 20 to 30 ° C. for 1 hour. After completion of dropping, the mixture was reacted at 30 ° C. for 15 hours, 1.82 g of acetic acid was added, and the mixture was stirred at the same temperature for 1 hour. After the reaction mixture was filtered and washed (dioxane), the filtrate was added to 5.32 g of acetic acid and 532 g of ion-exchanged water and stirred, and the precipitated crystals were filtered.
The obtained cake was washed with 532 g of deionized water and then dried at 40 ° C. to obtain a photosensitizer A. Synthesis Example 2 Honshu Chemical Co., Ltd. TPPA1100-2C [general formula (Ia) Z ₁ to Z ₆ are all by methylation - hydroxycarboxylic a benzyl group compound] 16g, 1,2-naphthoquinonediazide-5
6.79 g of triethylamine was added dropwise to a mixture of 15 g of sulfonic acid chloride and 155 g of dioxane at 20 to 30 ° C. for 1 hour. After completion of dropping, react at 30 ° C for 15 hours, and then acetic acid 1.
After adding 68 g, the mixture was stirred at the same temperature for 1 hour. After the reaction mixture was filtered and washed (dioxane), the filtrate was added to 5.1 g of acetic acid and 510 g of ion-exchanged water and stirred, and the precipitated crystals were filtered. After washing the obtained cake with 510 g of ion-exchanged water, 40
Photosensitizer B was obtained by drying at ° C. Synthetic Example 3 TPPA1200-26X manufactured by Honshu Kagaku Co., Ltd. [a compound in which Z _{1 to} Z ₆ are all 3,5-dimethyl-4-hydroxybenzyl groups in the general formula (Ia)] 16 g, 1,2-naphthoquinonediazide 14 g of 5-sulfonic acid chloride and dioxane
In a mixture of 150 g, 6.32 g of triethylamine at 20-30 ° C
-Drip in 1 hour. After completion of dropping, the mixture was reacted at 30 ° C. for 15 hours, 1.56 g of acetic acid was added, and the mixture was stirred at the same temperature for 1 hour. After the reaction mixture was filtered and washed (dioxane), the filtrate was added to 4.9 g of acetic acid and 492 g of ion-exchanged water and stirred, and the precipitated crystals were filtered. The resulting cake is deionized water
After washing with 492 g, it was dried at 40 ° C. to obtain a photosensitizer C.

Claims (1)

[Claims] 1. General formulas (Ia) and (Ib): [Wherein Z _{1 to} Z ₁₂ are each independently represented by the following formula: (In the formula, each of R _{1 to} R ₃ independently represents hydrogen or a halogen atom, —OCOR ₄ or an optionally substituted cycloalkyl, alkyl or alkoxy group,
R ₄ represents an optionally substituted cycloalkyl, alkyl or phenyl group. ) Represents a group represented by. ] At least 1 of the phenol compounds shown by
A positive resist composition comprising a quinonediazide-based photosensitizer containing one quinonediazide sulfonate and an alkali-soluble resin.