JP2002303977A - Photosensitive resin composition and positive type pattern forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition comprising a polyimide precursor developable with an aqueous alkali solution and having positive type pattern forming capacity and to provide a new positive type pattern forming method. SOLUTION: The photosensitive resin composition is a positive type photosensitive resin composition consisting of (A) a polyimide precursor having a phenolic hydroxyl group in each ester structure moiety, (B) a vinyloxy-containing compound such as triethylene glycol divinyl ether, (C) a photosensitive agent which is decomposed under active light such as UV and generates an acid, (D) a sensitizer which accelerates the decomposition of the above photo-acid generator, e.g. pyrene and (E) a solvent. In the positive type pattern forming method, a coating film insoluble in an alkaline aqueous solution is formed from the components (A) and (B), exposed with active UV and heated, only parts exposed and decomposed by the acid generated from the component (C) are dissolved in the alkaline aqueous solution to form a positive type pattern by development, and this positive type pattern is subjected to imidation heat treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyimide-based photosensitive resin composition used as an electrical or electronic insulating material in the manufacture of semiconductor devices and the like. It is formed on a semiconductor element such as a semiconductor device or an LSI, and is applied to the formation of an insulating protective film that requires fine pattern processing.

[0002]

2. Description of the Related Art In recent years, polyimide resins have been developed in the fields of electricity and electronics, including semiconductors, due to their high heat resistance, chemical resistance, electrical insulation, low dielectric constant, and the like. , IC, LSI and VLSI chips are used as interlayer insulating films and surface protective films. However, in the conventional pattern forming method, after a polyimide precursor is applied on a wafer and dried to form a polyimide resinized film, pattern etching using a photoresist must be performed. In addition, a harmful hydrazine solution had to be used as a polyimide etching solution.

[0003] For this reason, attempts to introduce a photosensitive group into a polyimide precursor to enable pattern formation of the polyimide itself have been made by various material manufacturers, and are in the practical stage in some product fields. However, photosensitive polyimides currently in practical use can be broadly classified into those in which photosensitive groups are introduced into the polyimide precursor through ionic bonds and those in which photosensitive groups are introduced through ester bonds. The sensitivity is low (the solubility difference is low) with respect to the exposure apparatus used in the process, and the process margin is low because the solubility of the resin decreases in the process. Also,
In the latter case, a complicated process is required for the production of the polyimide precursor, and a high-molecular-weight product having a practically usable high molecular weight cannot be obtained. Further, these resins employ a negative pattern forming method, and must be developed with an organic solvent when forming a pattern, which is a serious problem from the viewpoint of environmental conservation.

Recently, as a positive photosensitive resin composition, a composition in which a diazonaphthoquinone compound is added to polybenzoxazole has been proposed. However, this resin composition is inferior to polyimide resin in heat resistance and chemical resistance, and can be applied only to limited semiconductor products. In addition, this resin composition is compared with a positive resist widely used at the time of forming a semiconductor circuit, for example, a resin composition obtained by mixing diazonaphthoquinone with a novolak resin.
Low sensitivity to ultraviolet light and poor pattern forming ability. For this reason, defects such as a thin film remaining during pattern development and an excessively large pattern size have occurred.
From these problems, there is a strong demand for a positive photosensitive polyimide precursor that can use an aqueous alkaline solution at the time of pattern formation, and that does not swell with the developer and can increase the resolution.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional disadvantages and to provide a positive photosensitive resin composition containing a polyimide precursor having a positive pattern forming ability which can be developed with an alkaline aqueous solution. And a method for forming a positive pattern.

[0006]

Means for Solving the Problems As a result of diligent research aimed at achieving the above object, the present inventor has adopted a novel positive photosensitive resin composition having a composition described later and a method for forming a positive pattern thereof. By doing so, the inventors have found that the above object can be achieved, and have completed the present invention.

That is, the positive photosensitive resin composition of the present invention comprises (A) a polyimide precursor represented by the following general formula:

Embedded image(However, in the formula, R¹Is a tetravalent aromatic group, a plurality of aromatic groups
A tetravalent organic group having a single bond or a plurality of aromatic rings
-O-, -CO-, -SO_Two-, -CH_Two-Or-
C (CF_Three)_TwoA tetravalent organic group linked by-
^Two, R^ThreeIs a divalent aromatic group, in which a plurality of aromatic rings are a single bond
Divalent organic group or a plurality of aromatic rings is -O-,-
CO-, -SO_Two-, -CH_Two-Or -C (C
F_Three)_TwoA divalent organic group linked by-^Four, R
^FiveIs a divalent aromatic group in which a plurality of aromatic rings are single-bonded
A divalent organic group, or a plurality of aromatic rings represented by -O-, -CO
-, -SO _Two-, -CH_Two-Or -C (CF_Three)_Two
-Is a divalent organic group linked by-. Also, R⁶,
R⁷, R⁸, R⁹Is a hydrogen atom or
Aromatic alcohol having one or more phenolic hydroxyl groups
This is the residue obtained by esterifying the compound. (B) Next one
A vinyloxy group-containing compound represented by the general formula,

Embedded image(However, in the formula, R^TenIs a divalent or trivalent aliphatic group
Or an aromatic group or a plurality of aliphatic or aromatic rings
Single bond, -O-, -CO-, -SO_Two-, -CH _Two−,
-NH- or -C (CF_Three)_TwoDivalent linked with-
Or a trivalent organic group. I is an integer of 1 to 3,
n is an integer of 2 to 3. (C) For actinic rays such as ultraviolet rays
On the other hand, a photosensitizer that decomposes to generate an acid, (D) and (C)
Consisting of a sensitizer and a solvent (E) for accelerating the decomposition of the photosensitizer
It is characterized by the following.

Further, the method of forming a positive pattern according to the present invention comprises the step of coating the above-mentioned positive type photosensitive resin composition on a substrate and drying at 70 to 150 ° C. to form an insolubilized coating film for an alkaline aqueous solution. A film forming step;
After exposing the obtained insolubilized coating film to active ultraviolet light through a positive mask pattern, heating the film at 70 to 150 ° C. to decompose only the exposed portion of the insolubilized coating film,
A positive pattern development step of dissolving only the exposed and decomposed portions of the exposed coating film using an alkaline aqueous solution to develop a positive pattern, and a heat treatment of imidization for heat treatment of the developed positive pattern to form a positive pattern of polyimide And a step.

Hereinafter, the present invention will be described in detail.

The acid component serving as the R ¹ skeleton of the polyimide precursor (A) used in the present invention includes, for example, pyromellitic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ', 4'-biphenyltetracarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, 4,4'-oxydiphthalic acid, 3,3 ', 4
4'-diphenylsulfonetetracarboxylic acid, 2,2-
Bis (3,4-dicarboxyphenyl) hexafluoropropane, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid,
1,4,5,8-naphthalenetetracarboxylic acid, 1,
2,3,4-cyclobutanetetracarboxylic acid, 1,2,2
3,4-butanetetracarboxylic acid, 1,2,4,5-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3 ', 4,4'-bicyclohexyltetracarboxylic Acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-
Examples thereof include 1,2,3,4-tetrahydronaphthalene-1-succinic acid and anhydrides thereof, and these can be used alone or in combination.

The diamine component serving as the R ² and R ³ skeletons of the polyimide precursor (A) used in the present invention includes, for example,
m-phenylenediamine, p-phenylenediamine,
2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminotoluene, 1-methoxy-2,4-diaminobenzene, 1,
4-diamino-2-methoxy-5-methylbenzene,
1,3-diamino-4,6-dimethylbenzene, 3,5
-Diaminobenzoic acid, 2,5-diaminobenzoic acid, 1,
2-diaminonaphthalene, 1,4-diaminonaphthalene, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene, 2,6
-Diaminonaphthalene, 1,4-diamino-2-methylnaphthalene, 1,5-diamino-2-methylnaphthalene, 1,3-diamino-2-phenylnaphthalene, 2,
2-bis (4-aminophenyl) propane, 1,1-bis (4-aminophenyl) ethane, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-Tetramethyl-4,4'-diaminodiphenylmethane, 3,
3'-dimethyl-5,5'-diethyl-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetraethyl-4,4'-diaminodiphenylmethane, 4,4'
-Methylenebis (cyclohexylamine), 4,4'-
Methylene bis (3,3-dimethyl-cyclohexylamine), 2,4'-diaminodiphenyl sulfide, 4,
4'-diaminodiphenylsulfide, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 4,4'-diaminobenzanilide,
3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, bis (4-aminophenyl) diethylsilane, bis (4-aminophenyl) diphenylsilane,
Bis (4-aminophenyl) -N-methylamine, bis (4-aminophenyl) -N-phenylamine, 3,
3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,6-diaminopyridine, 3,5-diaminopyridine, 4,4'-diaminobiphenyl, 3,
3'-diaminobiphenyl, 3,3'-dimethyl-4,
4'-diaminobiphenyl, 3,3'-dimethoxy-
4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, o-toluidinesulfone, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-
Aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 9,10-bis (4-aminophenyl) anthracene, 9,9- Bis (4-aminophenyl) fluorene, 2,2-bis (4
-Aminophenyl) hexafluoropropane, 2,2-
Bis (3-aminophenyl) hexafluoropropane,
1,1-bis (4-aminophenyl) -1-phenyl-
2,2,2-trifluoroethane, 2,2-bis (3-
Amino-4-hydroxyphenyl) hexafluoropropane, 2,2-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2-bis [4- (4
-Aminophenoxy) phenyl] hexafluoropropane and the like, and these can be used alone or in combination of two or more.

The acid component serving as the R ⁴ and R ⁵ skeletons of the (A) polyimide precursor used in the present invention is, for example, maleic acid,
Succinic acid, isophthalic acid, nadic acid, oxynadic acid, dimethyloxynadic acid, diethyloxynadic acid, 3,4-dicarboxyphenylacetylene and the like and anhydrides thereof, and these may be used alone or in combination of two or more. Can be used.

In the present invention, a compound having an R ⁶ or R ⁷ skeleton is introduced into an acid anhydride having an R ¹ skeleton via an ester bond, and an acid anhydride having an R ⁴ skeleton is introduced via an ester bond into an acid anhydride having an R ⁴ skeleton. , compounds with R ⁸ skeleton is introduced via an ester bond to the acid anhydride having R ⁵ skeleton, R ⁹
Examples of the compound having a skeleton include a hydrogen atom or, for example, the following.

[0014]

Embedded image These compounds are more preferable in the present invention, but are not limited to the above structure as long as they are aromatic alcohol compounds having a phenolic hydroxyl group at a terminal. These can be used alone or in combination of two or more. As the reaction solvent for the esterification, the above-mentioned aprotic polar solvent favorable for the synthesis of the polyimide precursor is used, and in the presence of a basic catalyst for smoothly performing the reaction, for example, triethylamine, pyridine, triethanolamine, etc., at room temperature. It is preferable to carry out.

As the solvent for the polycondensation reaction between the acid component having the R ¹ skeleton and the diamine component having the R ² skeleton of the polyimide precursor (A) used in the present invention, for example, N-methylpyrrolidone, N, N'- An aprotic polar solvent such as dimethylacetamide and N, N'-dimethylformamide, cyclohexanone, cyclopentanone, γ-butyrolactone and the like are used, and these can be used alone or in combination of two or more. In addition, in order to improve the film properties of the resin, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, or the like may be used alone or in combination of two or more. Can be used.

[0016] (B) used in the present invention vinyloxy group-containing compound having R ¹⁰ backbone is one having a vinyloxy group (vinyl ether group) in compound terminal as a reactive group. For example, compounds represented by the following chemical formulas 6 to 10 can be mentioned, and these can be used alone or in combination of two or more. The addition amount is preferably 1 to 10 parts by weight based on 100 parts by weight of the photosensitive resin composition. If the amount is less than 1 part by weight, the effect is not obtained. If the amount exceeds 10 parts by weight, the properties of the obtained coating film are deteriorated.

[0017]

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image Examples of the photosensitizer (C) which decomposes to actinic rays such as ultraviolet rays and generates an acid used in the present invention include, for example,
The compound shown in Chemical formula 20 is exemplified. These compounds are more preferable in the present invention, but are not limited to the above structure as long as they can be decomposed by irradiation with active ultraviolet rays to efficiently generate an acid. These can be used alone or in combination, and the amount of addition is 0.1 to 100 parts by weight of the photosensitive resin composition.
20 parts by weight are preferred. When the amount is less than 0.1 part by weight, the sensitivity to ultraviolet rays is low, and when the amount exceeds 20 parts by weight, the properties of the obtained coating film deteriorate.

[0018]

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image The sensitizer (D) used in the present invention promotes the decomposition of the component (C) against actinic rays such as ultraviolet rays, and examples thereof include compounds represented by the following formula (21). These compounds are more preferred in the present invention,
The structure is not limited to the above structure as long as it promotes the decomposition of the compound (C). These can be used alone or as a mixture, and the addition amount thereof is preferably 0.1 to 20 parts by weight based on 100 parts by weight of the photosensitive resin composition. When the amount is less than 0.1 part by weight, the sensitivity to ultraviolet rays is low, and when the amount exceeds 20 parts by weight, the properties of the obtained coating film deteriorate.

[0019]

Embedded image Further, the photosensitive resin composition obtained by the present invention,
(E) It is used in the state of being dissolved in a solvent. Examples of the solvent (E) include N-methylpyrrolidone, N, N '
Aprotic polar solvents such as -dimethylacetamide, N, N'-dimethylformamide, cyclohexanone,
Cyclopentanone, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, γ-butyrolactone, etc., and these can be used alone or in combination of two or more. .

Next, a method for forming a positive pattern using the photosensitive resin composition obtained by the present invention will be described.

When application to a semiconductor device is considered, first, this resin composition is coated on a target wafer using a spin coater, and then the coating film is dried at 70 to 150 ° C. An active ultraviolet ray having a wavelength of 365 nm or 436 nm is irradiated through a mask having a pattern drawn on the obtained coating film. Next, the coating film is heated again at 70 to 150 ° C., and then the coating film is successively applied with an alkaline aqueous solution, for example, an aqueous solution of an inorganic alkali such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia, ethylamine, or n-propyl. Primary amines such as amines,
Secondary amines such as diethylamine and di-n-propylamine; tertiary amines such as triethylamine and methyldimethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; and tetraamines such as tetramethylammonium hydroxide and tetraethylammonium hydroxide. Only the actinic ray irradiated portion is dissolved and developed using an aqueous solution of a graded amine, and rinsed with pure water. As a developing system, a system such as spray, paddle, immersion, and ultrasonic wave can be considered. Thereby, a desired positive pattern can be obtained on the target wafer. further,
By subjecting this coating film to a heat treatment at, for example, 150 ° C. for 1 hour, 250 ° C. for 1 hour, and 350 ° C. for 1 hour, the resin composition is imidized and a polyimide film having excellent film properties can be formed.

[0022]

The most significant feature of the present invention is that the present inventors have made intensive studies and as a result have found a positive pattern formation mechanism described below and have increased the sensitivity. In the positive pattern forming method, the resin composition may be a general formula having R ¹ , R ² , R ³ , R ⁴ , and R ⁵ skeletons in a drying step of drying the insolubilized coating film after spin coating on a substrate. R ⁶ , R ⁷ , R ⁸ , R ^{9 of the} polyimide precursor
Carboxyl or phenolic hydroxyl site with a skeleton, react chemically with the compounds having the R ¹⁰ skeleton, insolubilized in an alkali aqueous solution. Next, by irradiating the insolubilized coating film with actinic rays such as ultraviolet rays, the photoacid generator in the actinic ray-exposed area is decomposed to generate an acid. Further, in the exposure coating film decomposition step of heating, the generated acid decomposes the chemical bond, and again R ¹ , R ² , R ³ , R ⁴
It returns to the polyimide precursor polymer having a skeleton to regenerate carboxyl groups or phenolic hydroxyl groups. The carboxyl group or phenolic hydroxyl group of this polymer has high solubility in an alkaline aqueous solution. As a result, only the part irradiated with actinic rays such as ultraviolet rays shows high solubility in the alkaline aqueous solution, and the unirradiated part is insolubilized. It does not melt at all. Due to this high contrast, the photosensitive resin composition of the present invention can form a positive pattern with high resolution and good dimensional control. In addition, since a compound that promotes the decomposition of the photoacid generating photosensitizer described above was found, the decomposition of the photoacid generating photosensitizer in the active light irradiation portion was further promoted by irradiating actinic rays such as ultraviolet rays, and many acids were exposed. Since the unirradiated portion is not affected and remains insoluble in an alkaline aqueous solution, a positive pattern having higher contrast and higher sensitivity than before can be formed. Further, in the step of heat-treating this coating film to imidize the resin composition,
Simultaneously with imidation, the double bond or triple bond site contained in the R ¹ , R ² , R ³ , R ⁴ , R ⁵ skeleton reacts with the double bond or triple bond site in another polymer having a similar skeleton. Therefore, it has become possible to form a polyimide film having better film characteristics than ever before.

Further, in the resin compositions containing the diazonaphthoquinone compounds proposed so far, low sensitivity to actinic rays has been an issue. The main cause is derived from diazonaphthoquinone compounds. That is, the addition of a large amount of the diazonaphthoquinone compound lowers the transmittance of actinic rays, thereby lowering the sensitivity. In the photosensitive resin composition of the present invention, in order to form a positive pattern without using a diazonaphthoquinone compound, not only has a good active light transmittance, but also repeatedly uses an acid generated from a photoacid generator. Therefore, sufficient pattern forming ability can be exhibited even with a low amount of active light. Since this reaction mechanism can cause a chemical reaction in an amplifying manner, it has become possible to provide a highly sensitive photosensitive resin composition in the present invention.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on embodiments.

Example 1 First, 2 mol of 4,4'-diaminodiphenyl ether and 2 L of N-methyl-2-pyrrolidone were added to a reaction flask equipped with a nitrogen introducing tube, and the mixture was stirred and dissolved for 1 hour.
Next, 1 mol of benzophenonetetracarboxylic dianhydride is added in three portions, and a condensation reaction is performed for 6 hours in this state. Thereafter, 2 mol of maleic anhydride is added in three portions, and polymerization is carried out for 6 hours in this state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 20 g of dried solid resin, 10 g of triethylene glycol divinyl ether, 1.0 g of 1,8-naphthalimidyl triflate and 0.5 g of pyrene were added to 30 g of N-
It was dissolved in methyl-2-pyrrolidone, and the obtained slurry was filtered at 1 μm to give Sample 1.

This sample 1 was coated on a 6-inch silicon wafer using a spin coater, and dried by heating at 100 ° C. for 4 minutes on a bake plate.
A μm coating was obtained. The coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 100 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, the mixture was heated at 120 ° C. for 1 minute. Then the 2.38% T
Paddle development was performed for 60 seconds using an aqueous solution of MAH (tetramethylammonium hydride), followed by washing with pure water. By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained.
Observation of the obtained pattern with an optical microscope confirmed that a pattern up to 3.0 μm was formed sharply. At this time, the change in film thickness during development was 0.3 μm, which was almost unchanged, and it was observed that the film was insoluble.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
A sharp profile was maintained without collapse even in the heat treatment.

Example 2 First, 2 mol of 4,4'-diaminodiphenyl ether and 2 L of N-methyl-2-pyrrolidone were added to a reaction flask equipped with a nitrogen introducing tube, and the mixture was stirred and dissolved for 1 hour.
Next, 1 mol of biphenyltetracarboxylic dianhydride is added in three portions, and a condensation reaction is performed for 6 hours in this state. Thereafter, 2 mol of nadic anhydride is added in three portions, and polymerization is carried out for 6 hours in this state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 20 g of the dried solid resin and 2,2-bis [4-
(2-vinyloxyethoxy) phenyl] propane and 10
g, 1.0 g of 1,8-naphthalimidyl triflate and 0.5 g of pyrene were dissolved in 30 g of N-methyl-2-pyrrolidone, and the obtained slurry was filtered at 1 μm to give Sample 2.

This sample 2 was coated on a 6-inch silicon wafer using a spin coater, and dried by heating at 100 ° C. for 4 minutes on a bake plate.
A μm coating was obtained. The coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 100 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, the mixture was heated at 120 ° C. for 1 minute. Then the 2.38% T
Paddle development was performed for 60 seconds using an aqueous solution of MAH (tetramethylammonium hydride), followed by washing with pure water. By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained.
Observation of the obtained pattern with an optical microscope confirmed that a pattern up to 3.0 μm was formed sharply. At this time, the change in film thickness during development was 0.3 μm, which was almost unchanged, and it was observed that the film was insoluble.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
A sharp profile was maintained without collapse even in the heat treatment.

Example 3 First, 1 mol of benzophenonetetracarboxylic dianhydride and 2 L of N-
2.1 mol of methyl-2-pyrrolidone and P-hydroxybenzyl alcohol were added and stirred.
1 of triethylamine is added dropwise over 30 minutes. After standing for 3 hours in this state, 1.0 mol of 4,4 '
Add diaminodiphenyl ether and stir for 30 minutes to dissolve. Next, 2.1 mol of diphenyl (2,3
-Dihydro-2-thioxo-3-benzoxazole)
The phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. Further, 2 mol of maleic anhydride and 2.1 mol of 1 L of N-methyl-2-pyrrolidone and P-hydroxybenzyl alcohol were added to a reaction flask 2 equipped with another nitrogen inlet tube, and stirred, followed by 2.1 mol. Of triethylamine is added dropwise over 30 minutes. 3 in this state
After standing for a time, the solution in the reaction flask 2 is mixed with the reaction flask 1 and stirred for 30 minutes. Next, 2.1 mol of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 20 g of the dried solid resin, 10 g of triethylene glycol divinyl ether, 1.0 g of 1,8-naphthalimidyl triflate and 0.5 g of pyrene are dissolved in 30 g of N-methyl-2-pyrrolidone to obtain a slurry. Was filtered by 1 μm to obtain Sample 3.

This sample 3 was coated on a 6-inch silicon wafer using a spin coater, and dried by heating at 100 ° C. for 4 minutes on a baking plate.
A μm coating was obtained. The coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 100 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, the mixture was heated at 120 ° C. for 1 minute. Then the 2.38% T
Paddle development was performed for 60 seconds using an aqueous solution of MAH (tetramethylammonium hydride), followed by washing with pure water. By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained.
Observation of the obtained pattern with an optical microscope confirmed that a pattern up to 3.0 μm was formed sharply. At this time, the change in film thickness during development was 0.3 μm, which was almost unchanged, and it was observed that the film was insoluble.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
A sharp profile was maintained without collapse even in the heat treatment.

EXAMPLE 4 First, 1 mol of hexafluoroisopropylidene-2,2'-bisphthalic dianhydride and 2 L of N-methyl-2-pyrrolidone and P-
2.1 mol of hydroxybenzyl alcohol was added and stirred, and then 2.1 mol of triethylamine was added to 30 mol.
Drop in minutes. In this state, the mixture is left for 3 hours, and after completion of the reaction, 1.0 mol of 4,4'-diaminodiphenyl ether is added, and the mixture is stirred and dissolved for 30 minutes. Next, 2.1m
ol diphenyl (2,3-dihydro-2-thioxo-
(3-Benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. Further, 2 mol of nadic anhydride and 2.1 mol of 1 L of N-methyl-2-pyrrolidone and P-hydroxybenzyl alcohol were added to a reaction flask 2 equipped with another nitrogen inlet tube, followed by stirring, followed by 2.1 mol. Of triethylamine is added dropwise over 30 minutes. After being left for 3 hours in this state, the solution in the reaction flask 2 is mixed with the reaction flask 1 and stirred for 30 minutes. Next, 2.1 mol of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 20 g of the dried solid resin, 2,2-bis [4- (2-vinyloxyethoxy) phenyl] propane, 10 g, 1.0 g of 1,8-naphthalimidyl triflate and 0.5 g of pyrene are added to 30 g of N-methyl. -2 was dissolved in pyrrolidone, and the obtained slurry was filtered at 1 μm to give Sample 4.

This sample 4 was coated on a 6-inch silicon wafer using a spin coater, and was dried by heating at 100 ° C. for 4 minutes on a bake plate.
A μm coating was obtained. The coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 100 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, the mixture was heated at 120 ° C. for 1 minute. Then the 2.38% T
Paddle development was performed for 60 seconds using an aqueous solution of MAH (tetramethylammonium hydride), followed by washing with pure water. By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained.
Observation of the obtained pattern with an optical microscope confirmed that a pattern up to 3.0 μm was formed sharply. At this time, the change in film thickness during development was 0.3 μm, which was almost unchanged, and it was observed that the film was insoluble.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
A sharp profile was maintained without collapse even in the heat treatment.

Example 5 First, 1 mol of hexafluoroisopropylidene-2,2'-bisphthalic dianhydride and 2 L of N-methyl-2-pyrrolidone were added to a reaction flask 1 equipped with a nitrogen inlet tube.
2.1 mol of 5-dihydroxybenzyl alcohol is added and stirred, followed by dropwise addition of 2.1 mol of triethylamine in 30 minutes. In this state, the mixture is left for 3 hours, and after completion of the reaction, 1.0 mol of 4,4'-diaminodiphenyl ether is added, and the mixture is stirred and dissolved for 30 minutes. Next, 2.
1 mol of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. In a reaction flask 2 equipped with another nitrogen inlet tube, 2 mol of nadic anhydride and 2.1 mol of 1 L of N-methyl-2-pyrrolidone and 3,5-dihydroxybenzyl alcohol were added.
Then, 2.1 mol of triethylamine is added dropwise over 30 minutes. After being left for 3 hours in this state, the solution of the reaction flask 2 was mixed with the reaction flask 1,
Stir for 30 minutes. Next, 2.1 mol of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 30 g of dried solid resin 20 g, 2,2-bis [4- (2-vinyloxyethoxy) phenyl] propane 10 g, 1,8-naphthalimidyl triflate 1.0 g and pyrene 0.5 g
Was dissolved in N-methyl-2-pyrrolidone, and the resulting slurry was filtered at 1 μm to give Sample 5.

This sample 5 was coated on a 6-inch silicon wafer using a spin coater, and dried by heating at 100 ° C. for 4 minutes on a baking plate.
A μm coating was obtained. The coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 100 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, the mixture was heated at 120 ° C. for 1 minute. Then the 2.38% T
Paddle development was performed for 60 seconds using an aqueous solution of MAH (tetramethylammonium hydride), followed by washing with pure water. By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained.
Observation of the obtained pattern with an optical microscope confirmed that a pattern up to 3.0 μm was formed sharply. At this time, the change in film thickness during development was 0.3 μm, which was almost unchanged, and it was observed that the film was insoluble.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
A sharp profile was maintained without collapse even in the heat treatment.

Comparative Example First, 1 mol of hexafluoroisopropylidene-2,2'-bisphthalic acid dianhydride and 2 L of N-methyl-2-pyrrolidone and P-
2.1 mol of hydroxybenzyl alcohol was added and stirred, and then 2.1 mol of triethylamine was added to 30 mol.
Drop in minutes. In this state, the mixture is left for 3 hours, and after completion of the reaction, 1.0 mol of 4,4'-diaminodiphenyl ether is added, and the mixture is stirred and dissolved for 30 minutes. Next, 2.1m
ol diphenyl (2,3-dihydro-2-thioxo-
(3-Benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. Further, 2 mol of nadic acid anhydride and 2.1 mol of 1 L of N-methyl-2-pyrrolidone and P-hydroxybenzyl alcohol were added to a reaction flask 2 equipped with another nitrogen inlet tube, followed by stirring. 1 mol of triethylamine is added dropwise over 30 minutes. After being left for 3 hours in this state, the solution in the reaction flask 2 is mixed with the reaction flask 1 and stirred for 30 minutes. Next, 2.1 mol of diphenyl (2,3-dihydro-2-thioxo-3-benzoxazole) phosphonate is added in five portions, and a condensation reaction is performed for 5 hours in that state. The obtained slurry mixture is poured into a large amount of methanol for washing, and the obtained solid resin is dried by a vacuum dryer for 12 hours. 20 g of the dried solid resin and 5 g of a benzophenone-type disubstituted diazonaphthoquinone compound were dissolved in 30 g of N-methyl-2-pyrrolidone,
The obtained slurry was filtered at 1 μm to obtain Sample 6.

This sample 6 was coated on a 6-inch silicon wafer using a spin coater, and was dried by heating at 120 ° C. for 4 minutes on a baking plate.
A μm coating was obtained. This coating film was irradiated with an ultraviolet light using a filter that transmits only 365 nm to a thickness of 500 nm.
irradiating a test pattern with energy of mj / cm ² ,
Subsequently, paddle development was performed for 1 minute with a 2.38% aqueous solution of TMAH (tetramethylammonium hydride). By this operation, a positive relief pattern in which only the ultraviolet irradiation part of the coating film was dissolved was obtained. Observation of the obtained pattern with an optical microscope revealed that
It was confirmed that a pattern up to 5.0 μm was formed. However, this pattern was swollen and not a sharp shape.

Further, this pattern was applied at 150 ° C. for 1 hour and 2 hours.
Heat treatment at 50 ° C for 1 hour and 350 ° C for 1 hour,
The imidization of the coating film was completed. This imide pattern is
It was firmly adhered on the silicon wafer, and no resin crack or peeling was observed in the pattern.

[0043]

The present invention is a photosensitive polyimide precursor having a positive pattern forming ability, and an alkaline aqueous solution can be used for pattern formation. Furthermore, since the photosensitive resin composition of the present invention reacts chemically with ultraviolet light, it has a high contrast, a high sensitivity, and a very sharp positive pattern with good dimensional control can be obtained. . Moreover, by adding a compound that promotes the decomposition of acid, higher sensitivity can be achieved.
Furthermore, the resin composition is heat-treated and imidized, and at the same time, a three-dimensional crosslinking reaction occurs between the polymers, so that a polyimide film having excellent film properties can be obtained. Since the polyimide film finally obtained is excellent in heat resistance and chemical resistance,
It has become possible to use the same as a commonly used semiconductor device protective film. These are based on a completely new idea, and it can be easily understood that they are unique and excellent inventions.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/027 H01L 21/30 502R F-term (Reference) 2H025 AA01 AA02 AA04 AA06 AB16 AC01 AD03 BE00 BE10 BG00 CB25 CB41 CC03 CC20 FA17 FA29 FA40 2H096 AA25 BA11 DA01 EA02 GA08 HA01 4J026 AB34 BA15 BA17 DB36 FA05 GA06 4J043 PA02 QB15 QB26 QB31 RA34 SA06 TA14 TA22 XA36 XA38 ZB47

Claims (2)

[Claims] (A) a polyimide represented by the following general formula:
Precursor,(However, in the formula, R¹Is a tetravalent aromatic group, a plurality of aromatic groups
A tetravalent organic group having a single bond or a plurality of aromatic rings
-O-, -CO-, -SO_Two-, -CH_Two-Or-
C (CF_Three)_TwoA tetravalent organic group linked by-
^Two, R^ThreeIs a divalent aromatic group, in which a plurality of aromatic rings are a single bond
Divalent organic group or a plurality of aromatic rings is -O-,-
CO-, -SO_Two-, -CH_Two-Or -C (C
F_Three)_TwoA divalent organic group linked by-^Four, R
^FiveIs a divalent aromatic group in which a plurality of aromatic rings are single-bonded
A divalent organic group, or a plurality of aromatic rings represented by -O-, -CO
-, -SO _Two-, -CH_Two-Or -C (CF_Three)_Two
-Is a divalent organic group linked by-. Also, R⁶,
R⁷, R⁸, R⁹Is a hydrogen atom or
Aromatic alcohol having one or more phenolic hydroxyl groups
This is the residue obtained by esterifying the compound. (B) Next one
A vinyloxy group-containing compound represented by the general formula:(However, in the formula, R^TenIs a divalent or trivalent aliphatic group
Or an aromatic group or a plurality of aliphatic or aromatic rings
Single bond, -O-, -CO-, -SO_Two-, -CH _Two−,
-NH- or -C (CF_Three)_TwoDivalent linked with-
Or a trivalent organic group. I is an integer of 1 to 3,
n is an integer of 2 to 3. (C) For actinic rays such as ultraviolet rays
On the other hand, a photosensitizer that decomposes to generate an acid, (D) and (C)
Consisting of a sensitizer and a solvent (E) for accelerating the decomposition of the photosensitizer
A positive photosensitive resin composition, characterized in that: 2. An insolubilized coating film forming step of coating the positive photosensitive resin composition according to claim 1 on a substrate and drying at 70 to 150 ° C. to form an insolubilized coating film for an alkaline aqueous solution. After exposing the insolubilized coating film to active ultraviolet light through a positive mask pattern,
Exposure coating decomposing step of heating at 0 ° C to decompose only the exposed part of the insolubilized coating, and positive pattern development of dissolving only the exposed decomposition part using an alkaline aqueous solution and developing the exposed coating into a positive pattern A positive pattern forming method, comprising: a step of heat treating the developed positive pattern to form a polyimide positive pattern by heat treatment.