JP2001051412A - Positive photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a positive photoresist composition capable of forming various resist patterns in a good shape even under the same exposure conditions and excellent in focal depth-width characteristics by incorporating an alkali- soluble resin and a photosensitive component containing a quinonediazido- esterified product of a specified compound. SOLUTION: The positive photoresist composition contains an alkali-soluble resin and a photosensitive component containing a quinonediazido-esterified product of a compound of the formula (where R1-R9 are each 1-3C alkyl or cyclohexyl). The alkali-soluble resin may be polyhydroxystyrene or its derivative. When the photoresist composition is used, various resist patterns such as a dense pattern, an isolated pattern and a dot pattern can be formed in a good shape even under the same exposure conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a positive photoresist composition capable of forming various resist patterns such as a dense pattern, an isolated pattern, and a dot pattern in a good shape.

[0002]

2. Description of the Related Art In recent years, attention has been focused on the production of high value-added logic ICs. However, in the production of highly integrated logic ICs, dense patterns, isolated patterns,
A photoresist composition capable of forming a resist pattern having various shapes such as a dot pattern in an ultra-fine region of half a micron or less with good shape is desired. Further, it is desired that each of those resist patterns can be formed with good shape under the same exposure conditions. But,
In a conventional photoresist composition, even if it is excellent in forming a dense pattern, it is not excellent in forming an isolated pattern or a dot pattern, or even if it can be formed, the dispersion of focal depth width characteristics in each pattern is large under the same exposure conditions. Therefore, it has been necessary to change the exposure conditions for each pattern shape, change the mask pattern dimensions, and the like.

JP-A-6-167805 (prior art 1) and JP-A-7-168355 (prior art 2) exemplify a quinonediazide ester having a specific structure as a photosensitive component. A high resolution positive photoresist composition is disclosed. But,
With the positive resist compositions specifically exemplified in Prior Art 1 and 2, it is difficult to form various resist patterns in good shape without changing the exposure conditions.

[0004] Japanese Patent Application Laid-Open No. 9-110751 (Prior Art 3) describes a phenol compound having a structure represented by a wide general formula, and describes that a quinonediazide esterified product of the phenol compound is useful as a photosensitive component. are doing. However, the esterified product in the present invention is not specifically described.

[0005]

Accordingly, an object of the present invention is to provide various resist patterns such as a dense pattern, an isolated pattern, and a dot pattern even under the same exposure conditions in the field of forming an ultrafine resist pattern of less than half a micron. An object of the present invention is to provide a positive photoresist composition which can be formed in a good shape and has excellent depth of focus characteristics.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a positive photoresist composition containing a quinonediazide esterified compound of the compound represented by the following general formula (I) has the same light exposure. Under the conditions, it has been found that various resist patterns such as a dense pattern, an isolated pattern, and a dot pattern can be formed in a good shape, and that they have excellent focal depth width characteristics.

That is, the present invention provides a positive photoresist composition comprising (A) an alkali-soluble resin and (B) a photosensitive component, wherein the (B) photosensitive component is represented by the following general formula (I): An object of the present invention is to provide a positive photoresist composition comprising a quinonediazide esterified compound of the compound represented by the formula (I).

[0008]

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The present invention also provides the above positive photoresist composition further comprising (C) a sensitivity enhancer (sensitizer).

The present invention also relates to a 2,6-bis [4-hydroxy-3 compound represented by the following general formula (II) as the component (B):
-(2-hydroxy-4,6-dimethylbenzyl)-
It is intended to provide the above positive photoresist composition comprising a quinonediazide ester of 2,5-dimethylbenzyl] -4-methylphenol.

[0011]

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In the present invention, the component (B) may be added in a proportion of:
An object of the present invention is to provide the positive photoresist composition described above, which accounts for 10 to 60% by weight based on the total amount of the component (A) and the component (C) optionally added.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION (A) Alkali-Soluble Resin The alkali-soluble resin as the component (A) is not particularly limited and may be any of those usually used as a film-forming substance in a positive photoresist composition. And preferably, a condensation reaction product of an aromatic hydroxy compound with an aldehyde or a ketone, polyhydroxystyrene and a derivative thereof.

As the aromatic hydroxy compound, for example, phenol, m-cresol, p-cresol, o
-Xylenols such as cresol, 2,3-xylenol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol; m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3, 5-trimethylphenol, 2,3,5-triethylphenol, 4-tert-butylphenol, 3-tert-
Butylphenol, 2-tert-butylphenol,
2-tert-butyl-4-methylphenol, 2-t
alkylphenols such as tert-butyl-5-methylphenol; alkoxyphenols such as p-methoxyphenol, m-methoxyphenol, p-ethoxyphenol, m-ethoxyphenol, p-propoxyphenol and m-propoxyphenol; Isopropenylphenol, p-isopropenylphenol, 2-
Methyl-4-isopropenylphenol, 2-ethyl-
Isopropenylphenols such as 4-isopropenylphenol; arylphenols such as phenylphenol; polyhydroxyphenols such as 4,4'-dihydroxybiphenyl, bisphenol A, resorcinol, hydroquinone, and pyrogallol. These may be used alone or in combination of two or more.

Examples of the aldehydes include formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, butyraldehyde, trimethylacetaldehyde, acrolein, crotonaldehyde, cyclohexanealdehyde, furfural, furylacrolein, benzaldehyde, terephthalaldehyde, phenylacetaldehyde, α -Phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde , P-chlorobenzaldehyde And cinnamic aldehyde. These may be used alone or in combination of two or more. Among these aldehydes, formaldehyde is preferable in terms of availability, but in particular, in order to improve heat resistance, it is preferable to use a combination of hydroxybenzaldehyde and formaldehyde.

The ketones include, for example, acetone, methyl ethyl ketone, diethyl ketone, diphenyl ketone and the like. These may be used alone or in combination of two or more. Furthermore, aldehydes and ketones may be used in an appropriate combination.

The condensation reaction product of the aromatic hydroxy compound with aldehydes or ketones can be produced by a known method in the presence of an acidic catalyst. Hydrochloric acid, sulfuric acid, formic acid, oxalic acid, p-toluenesulfonic acid and the like can be used as the acidic catalyst at that time.

Examples of the polyhydroxystyrene and derivatives thereof include homopolymers of vinyl phenol,
Copolymers of vinylphenol and comonomers copolymerizable therewith are exemplified. Examples of the comonomer include acrylic acid derivatives, acrylonitrile, methacrylic acid derivatives, methacrylonitrile, styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene,
Styrene derivatives such as p-methoxystyrene and p-chlorostyrene are exemplified.

Among them, the alkali-soluble resin as the component (A) suitable in the present invention has a weight average molecular weight (Mw).
2000 to 20000, especially 3000 to 12000
Preferred is an alkali-soluble novolak resin,
Alkali-soluble novolak resin obtained by condensation reaction of m-cresol and p-cresol with formaldehyde, alkali-soluble novolak resin obtained by condensation reaction of m-cresol, p-cresol and 2,3,5-trimethylphenol with formaldehyde The use of is preferred since a positive photoresist composition having high sensitivity and wide exposure latitude can be prepared.

(B) Photosensitive Component In the present invention, (B) the photosensitive component is represented by the following general formula (I)
Characterized by using a quinonediazide esterified compound of the compound represented by the formula:

[0021]

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In particular, the following general formula (II)

[0023]

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A quinonediazide ester of the compound represented by the formula (1) is preferred. The esterified product is synthesized by an esterification reaction between the compound represented by the above general formula (I) and 1,2-naphthoquinonediazidesulfonic acid halide. The esterification reaction is carried out in a range of from 1 to 4 mol, preferably from 2 to 3 mol, of 1,2-naphthoquinonediazidesulfonic acid halide to 1 mol of the compound represented by the above general formula (I). Is preferred. The average esterification ratio is in good agreement with the charged amount of each component. The average esterification ratio can be easily determined from the charged amount of 1,2-naphthoquinonediazidosulfonic acid halide and the unreacted amount. The average esterification rate is preferably 20 to 80%, particularly preferably 40 to 60%,
Within this range, under the same exposure conditions, dense, isolated,
It is preferable because it has an excellent effect of forming each resist pattern of dots in a good shape. If the average esterification ratio is less than 20%, the residual film ratio in the unexposed portion and the resolution will be remarkably reduced, and if it exceeds 80%, the sensitivity will be remarkably reduced.

As the photosensitive component (B) of the present invention, other quinonediazide esterified compounds can be used for the purpose of improving sensitivity and resolution. Examples of such a quinonediazide esterified product include the following general formula (III)

[0026]

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Wherein R ^{10 to} R ¹⁷ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms,
R ^{18 to} R ²⁰ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; Q represents a hydrogen atom or 1 carbon atom; 6 alkyl groups, bonded to R ^18, cyclo ring carbon atoms chain 3-6 or the following formula, (IV)
The residue represented by

[0028]

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Wherein R ²¹ and R ²² each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxyl group having 1 to 6 carbon atoms, or a cycloalkyl group; Represents an integer of 1 to 3);
a and b represent an integer of 1 to 3; d represents an integer of 0 to 3; n represents an integer of 0 to 3].
Specifically, 2,4-bis (3,5-dimethyl-4-hydroxybenzyl) -5-hydroxyphenol, 2,6
-Bis (2,5-dimethyl-4-hydroxybenzyl)
Linear trinuclear compounds such as -4-methylphenol; bis [2,5-dimethyl-3- (4-hydroxy-5-methylbenzyl) -4-hydroxyphenyl] methane, bis [2,5-dimethyl- 3- (4-hydroxybenzyl) -4-hydroxyphenyl] methane, bis [3-
(3,5-dimethyl-4-hydroxybenzyl) -4-
Hydroxy-5-methylphenyl] methane, bis [3-
(3,5-dimethyl-4-hydroxybenzyl) -4-
Hydroxy-5-ethylphenyl] methane, bis [3-
(3,5-diethyl-4-hydroxybenzyl) -4-
Hydroxy-5-methylphenyl] methane, bis [3-
(3,5-diethyl-4-hydroxybenzyl) -4-
Hydroxy-5-ethylphenyl] methane, bis [2-
Hydroxy-3- (3,5-dimethyl-4-hydroxybenzyl) -5-methylphenyl] methane, bis [2-
Hydroxy-3- (2-hydroxy-5-methylbenzyl) -5-methylphenyl] methane, bis [4-hydroxy-3- (2-hydroxy-5-methylbenzyl)-
Linear tetranuclear compound such as 5-methylphenyl] methane; 2,4-bis [2-hydroxy-3- (4-hydroxybenzyl) -5-methylbenzyl] -6-cyclohexylphenol, 2,4-bis [4-hydroxy-3
-(4-hydroxybenzyl) -5-methylbenzyl]
Linear polyphenol compounds such as linear pentanuclear compounds such as -6-cyclohexylphenol;
Hydroxyphenyl) methane, bis (4-hydroxy-
3,5-dimethylphenyl) -4-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -2- Hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -4-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -3
-Hydroxyphenylmethane, bis (4-hydroxy-
2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl)- 3,
4-dihydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -2,4-dihydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2,4-dihydroxyphenylmethane, Bis (4-hydroxyphenyl) -3-methoxy-
4-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxyphenyl) -3-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxyphenyl) -2-hydroxyphenylmethane, bis (3-cyclohexyl-4- Hydroxyphenyl) -4
-Hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -2-hydroxyphenylmethane, bis (3-cyclohexyl-4)
-Hydroxy-6-methylphenyl) -3-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methyl) Phenyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-6-hydroxyphenyl) -3-hydroxyphenylmethane, bis (3
-Cyclohexyl-6-hydroxyphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-
6-hydroxyphenyl) -2-hydroxyphenylmethane, bis (3-cyclohexyl-6-hydroxy-4)
-Methylphenyl) -2-hydroxyphenylmethane,
Bis (3-cyclohexyl-6-hydroxy-4-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-6-hydroxy-4-methylphenyl) -3,4-dihydroxyphenylmethane, bis (4- Hydroxy-2,3,5-trimethylphenyl)
-2-hydroxyphenylmethane, bis (4-hydroxy-2,3,5-trimethylphenyl) -3-hydroxyphenylmethane, bis (4-hydroxy-2,3,5
-Trimethylphenyl) -4-hydroxyphenylmethane, bis (4-hydroxy-2,3,5-trimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4-hydroxy-2,3,5-trimethylphenyl)
Quinonediazide esterified compounds such as trisphenol-like polyphenol compounds such as -4-hydroxy-3-methoxyphenylmethane are preferable. However, it is desired that the content of the quinonediazide esterified compound of the compound represented by the general formula (I) is 10% by weight or more, preferably 50% by weight or more based on the total amount of the component (B). Preferred above.

In the composition of the present invention, the compounding amount of the component (B) is such that the alkali-soluble resin as the component (A) and the sensitivity improver (sensitizer) of the following component (C) added as required. Is preferably from 10 to 60% by weight, more preferably from 20 to 50% by weight, based on the total amount of
When the amount of the component (B) is less than the above range, an image faithful to the pattern cannot be obtained, and the transferability is also reduced. on the other hand,
If the compounding amount of the component (B) exceeds the above range, the sensitivity is deteriorated, the uniformity of the formed resist film is reduced, and the resolution is deteriorated.

(C) Sensitivity enhancer (sensitizer) The (C) sensitivity enhancer (sensitizer) is not particularly limited, and a known one can be used. For example, a polyphenol compound represented by the above general formula (III) can be used. For example, bis (4-hydroxy-2,3,5-
Trimethylphenyl) -2-hydroxyphenylmethane, 1,4-bis [1- (3,5-dimethyl-4-hydroxyphenyl) isopropyl] benzene, 2,4-bis (3,5-dimethyl-4-hydroxyphenyl) Methyl) -6-methylphenol, bis (4-hydroxy-
3,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3, 4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-
Hydroxyphenyl) ethyl] benzene, 1- [1-
(3-methyl-4-hydroxyphenyl) isopropyl] -4- [1,1-bis (3-methyl-4-hydroxyphenyl) ethyl] benzene, 2,6-bis [1-
(2,4-dihydroxyphenyl) isopropyl] -4
-Methylphenol, 4,6-bis [1- (4-hydroxyphenyl) isopropyl] resorcin, 4,6-bis (3,5-dimethoxy-4-hydroxyphenylmethyl) pyrogallol, 4,6-bis (3 5-dimethyl-
4-hydroxyphenylmethyl) pyrogallol, 2,6
-Bis (3-methyl-4,6-dihydroxyphenylmethyl) -4-methylphenol, 2,6-bis (2
3,4-trihydroxyphenylmethyl) -4-methylphenol, 1,1-bis (4-hydroxyphenyl)
Cyclohexane and the like are preferred. Among them, bis (4-hydroxy-2,3,5-trimethylphenyl) -2-hydroxyphenylmethane, bis (4
-Hydroxy-3,5-dimethylphenyl) -3,4-
Dihydroxyphenylmethane, 2,4-bis (3,5-
Dimethyl-4-hydroxyphenylmethyl) -6-methylphenol, 4,6-bis [1- (4-hydroxyphenyl) isopropyl] resorcin, 1- [1- (4-
Hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene is particularly preferred.

When the component (C) is blended, the content thereof is 5 to 5% with respect to the alkali-soluble resin as the component (A).
It can be selected in the range of 50% by weight, preferably 10-35% by weight. In the present invention, it is more preferable to use the (C) sensitivity enhancer (sensitizer) in the above-mentioned range because the exposure latitude, the resolution, and the depth of focus width characteristic are further improved, and the sensitivity is excellent.

The composition of the present invention may further contain, if necessary, a compatible additive, an ultraviolet absorber for preventing halation such as 2,2 ', 4,4'-tetrahydroxybenzophenone, -Dimethylamino-2 ', 4'
-Dihydroxybenzophenone, 5-amino-3-methyl-1-phenyl-4- (4-hydroxyphenylazo) pyrazole, 4-dimethylamino-4'-hydroxyazobenzene, 4-diethylamino-4'-ethoxyazobenzene, 4- Diethylaminoazobenzene, curcumin and the like, and a surfactant for preventing striation, for example, Florade FC-430, FC431 (trade name, manufactured by Sumitomo 3M Co., Ltd.), F-Top EF122A,
Fluorinated surfactants such as EF122B, EF122C, and EF126 (trade name, manufactured by Tochem Products Co., Ltd.) can be added and contained as long as the object of the present invention is not hindered.

The composition of the present invention is preferably used in the form of a solution in which the components (A) to (C) and various additives are dissolved in a suitable solvent. Examples of such solvents include the solvents used in conventional positive photoresist compositions, such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone,
Ketones such as heptanone; ethylene glycol, propylene glycol, diethylene glycol, ethylene glycol monoacetate, propylene glycol monoacetate, diethylene glycol monoacetate, or monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether thereof; And cyclic ethers such as dioxane; and ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate. Esters can be mentioned. These may be used alone or as a mixture of two or more. In particular, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, and 2-heptanone; ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; Esters are preferred.

An example of a preferred method of using the composition of the present invention is as follows. First, the components (A), (B) and (C), and various components added as required, are described above. Dissolve in a suitable solvent like this, apply it on a silicone wafer or a support on which an antireflection film is formed with a spinner or the like, dry it to form a photosensitive layer, and then emit a UV light source, for example, a low pressure light source. Mercury lamp,
Exposure through a desired mask pattern using a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, an arc, a xenon lamp, or the like,
Alternatively, irradiation is performed while scanning an electron beam. Next, when this is immersed in a developing solution, for example, an alkaline aqueous solution such as a 1 to 10% by weight aqueous solution of tetramethylammonium hydroxide (TMAH), the exposed portions are dissolved and removed, and an image faithful to the mask pattern can be obtained.

[0036]

The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. The physical properties of the positive photoresist composition were determined as follows and are shown in Table 1.

(1) A sensitivity sample was applied on a silicon wafer using a spinner, and dried on a hot plate at 90 ° C. for 90 seconds to obtain a resist film having a thickness of 1.05 μm. A reduction projection exposure apparatus NSR-2005i10D (manufactured by Nikon Corporation) is applied to this film via a mask (reticle) corresponding to a 0.35 μm resist pattern in which the line and space (L & S) is 1: 1.
After exposure at 0.1 to 0.01 second intervals using NA = 0.57), PEB (post-exposure bake) treatment is performed at 110 ° C. for 90 seconds to obtain 2.38 wt% tetramethylammonium hydroxide. When developed with an aqueous solution at 23 ° C. for 60 seconds, washed with water for 30 seconds, and dried, the exposure time (Eop) at which the L & S width of the 0.35 μm resist pattern is formed to 1: 1 is defined as the sensitivity in millisecond (ms) units. It was expressed by.

(2-1) Depth of Focus Width Characteristics (Isolated Pattern
E ) Using a reduction projection exposure apparatus NSR-2005i10D (manufactured by Nikon Corporation, NA = 0.57), Eop [the set dimensions of the mask pattern (line width 0.35 μm, L & S 1: 1) are faithfully reproduced. Exposure required for this) was taken as a reference exposure, and the SEM photograph of the isolated resist pattern (0.35 μm in width) obtained by performing exposure and development by appropriately shifting the focus up and down at the exposure was observed. . The SE
The maximum value (μm) of the focus shift obtained by obtaining a rectangular resist pattern of 0.35 μm from the M photograph within the range of ± 10% of the set dimension was defined as the depth of focus width characteristic (isolated pattern).

(2-2) Depth of Focus Width Characteristics (Dense Putter
E ) Using a reduction projection exposure apparatus NSR-2005i10D (manufactured by Nikon Corporation, NA = 0.57), Eop [the set dimensions of the mask pattern (line width 0.35 μm, L & S 1: 1) are faithfully reproduced. Exposure amount required for the exposure) is set as a reference exposure amount. At the exposure amount, the focus is shifted up and down as appropriate, and exposure and development are performed to obtain a dense resist pattern (line width 0.35 μm, L & S is 1: 1). The SEM photograph was observed. From the SEM photograph, the maximum value (μm) of the focus deviation obtained when a rectangular resist pattern of 0.35 μm was obtained within a range of ± 10% of the set dimension was defined as the depth of focus width characteristic (dense pattern).

(2-3) Depth of Focus Width Characteristics (Dot Pattern
N) Reduced projection exposure apparatus NSR-2005i10D (manufactured by Nikon Corporation, NA = 0.57), sideways 0.6 μm × 0.6 μm
Using a mask with an m-dot pattern and a duty ratio of 2: 1 (interval between dots: 1.20 μm),
op [set dimensions of mask pattern (line width 0.35 μm,
Exposure amount required to faithfully reproduce L & S of 1: 1)] as a reference exposure amount, and at that exposure amount, the dot pattern (0. An SEM photograph of (6 μm × 0.6 μm) was observed. 0.6 μm × 0.6 μm from the SEM photograph
The maximum value (μm) of the focus shift obtained by the rectangular dot pattern in the range of ± 10% of the set dimension was defined as the depth of focus width characteristic (dot pattern).

(3) Total Depth-of-Focus Width Characteristics In the above evaluations (2-1) to (2-3), 0.35 μm of the resist pattern of any of the dense pattern, the isolated pattern, and the dot pattern was determined. The maximum value (μm) of the focus deviation obtained when the rectangular resist pattern was within ± 10% of the set dimension was defined as the total focal depth width characteristic.

(4) Resolution Line width is 0.35 μm, and L & S is represented by a limit resolution at an exposure amount for reproducing a mask pattern of 1: 1.

(Synthesis Example) 2.03 g of p-toluenesulfonic acid was added to 1 mol of 3,5-xylenol, and 50 to 6
The mixture was stirred at 0 ° C. and dissolved to prepare a solution 1. 2,6-bis (2,5-dimethyl-4-hydroxy-3-methylolbenzyl) -4- represented by the following general formula (V)
0.05 mol of methylphenol was added to γ-butyrolactone /
Methanol = 125/25 (weight ratio) mixed solvent 150
g, stirred at 25 ° C. and dissolved to prepare solution 2.

[0044]

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At a temperature of 60 ° C., the solution 2 was dropped into the solution 1 over 30 to 60 minutes, and the mixture was stirred for 3 hours while maintaining the temperature. Thereafter, the reaction solution was poured into 8 liters of pure water and allowed to stand for 3 hours, whereupon a reaction product was deposited.
The reaction product was filtered off, recrystallized from butyl acetate, and the obtained crystallized product was washed with toluene and dried to obtain a compound represented by the following general formula (II).

[0046]

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Example 1 Component (A): 100 parts by weight of alkali-soluble novolak resin [m-cresol / p-cresol / 2,3,5-trimethylphenol = 35/40/25 (molar ratio), weight average Novolak resin having a molecular weight of 4500] (B) component: 35 parts by weight of photosensitive component [1 mol of phenol compound (II) synthesized in Synthesis Example and 1,2-naphthoquinonediazide-5-sulfonic acid chloride (hereinafter referred to as “5-NQD”) ") Reaction product with 2.5 mol Average esterification rate 50%. Component (C): 20 parts by weight of a sensitivity improver: 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene The above (A) ) To (C) were dissolved in 2-heptanone, and then filtered using a membrane filter having a pore size of 0.2 μm to prepare a positive photoresist composition.

(Comparative Example 1) Instead of the component (B) used in Example 1, 1 mol of the following phenol compound (VI) and 5-N
A positive photoresist composition was prepared in the same manner as in Example 1 except that a reaction product with 2 mol of QD was used. In addition,
The average esterification was 50%.

[0049]

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Comparative Example 2 In place of the component (B) used in Example 1, 1 mol of the following phenol compound (VII) was added
A positive photoresist composition was prepared in the same manner as in Example 1 except that a reaction product with 2 mol of NQD was used. Incidentally, the average esterification rate was 50%.

[0051]

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Comparative Example 3 In place of the component (B) used in Example 1, 1 mol of the following phenol compound (VIII) was added
A positive photoresist composition was prepared in the same manner as in Example 1 except that a reaction product with 2.5 mol of NQD was used.
Incidentally, the average esterification rate was 50%.

[0053]

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With respect to the positive photoresist compositions prepared in Example 1 and Comparative Examples 1 to 3, the above (1) and (2-
1), (2-2), (2-3), (3), and (4)
Was evaluated, and the results are shown in Table 1.

[0055]

[Table 1]

From Table 1, it can be seen that the composition of the present invention has excellent focal depth width characteristics in any of the isolated pattern, dense pattern and dot pattern, and also has excellent sensitivity and resolution.

[0057]

According to the present invention, in the field of forming an ultra-fine resist pattern of half a micron or less, various resist patterns such as a dense pattern, an isolated pattern, and a dot pattern are formed in good shape even under the same exposure condition. And a positive photoresist composition having excellent depth of focus characteristics.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satoshi Aikura 150 Nakamurako Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Tokyo Ohka Kogyo Co., Ltd. (72) Inventor Hidekatsu Ohara 150 Nakamaruko Nakahara-ku Kawasaki City, Kanagawa Prefecture Within Industrial Co., Ltd.

Claims (4)

[Claims] 1. A positive photoresist composition comprising (A) an alkali-soluble resin and (B) a photosensitive component, wherein the (B) photosensitive component is represented by the following general formula (I). A positive photoresist composition comprising a quinonediazide ester of a compound. Embedded image 2. The positive photoresist composition according to claim 1, further comprising (C) a sensitivity enhancer (sensitizer). 3. A 2,6-bis [4-hydroxy-3- (2-hydroxy-4,6-dimethylbenzyl) -2,5-dimethyl represented by the following general formula (II) as a component (B): 3. The positive photoresist composition according to claim 1, comprising a quinonediazide ester of benzyl] -4-methylphenol. Embedded image 4. The mixing ratio of the component (B) is 1 to the total amount of the component (A) and the component (C) added as required.
4. The positive photoresist composition according to claim 1, wherein the amount is from 0 to 60% by weight.