JP2962103B2 - Photosensitive polyimide precursor composition for i-line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel photosensitive polyimide precursor composition.
The present invention relates to a photosensitive polyimide precursor composition for i-line applicable to both negative and positive types.

[0002]

2. Description of the Related Art The following are known negative photosensitive polyimide precursor compositions in which exposed portions remain after development.

(A) A composition comprising a polyamic acid to which a carbon-carbon double bond capable of being dimerized or polymerized by actinic radiation and an amino group or a quaternized salt thereof are added (for example, JP-B-59-5).
No. 2822).

(B) A composition in which acrylamides are added to polyamic acid (for example, JP-A-3-170555).

(C) A composition comprising a polyimide precursor having a carbon-carbon double bond group, a specific oxime compound, and a sensitizer (for example, JP-A-61-118423, No. 62-184,056, Japanese Unexamined Patent Publication No.
273259).

However, in these prior arts, when the thickness of the photosensitive polyimide precursor is increased, the photosensitivity is reduced, and the side of the pattern of the exposed portion is depressed during development, resulting in overhang. Or the physical properties of the film after imidization deteriorate.

The following are known as positive photosensitive polyimide compositions.

(D) A photosensitive polyimide precursor obtained by introducing photodegradable photosensitivity to an polyamide acid by an ester group (for example, JP-A-1-61747).

(E) A photosensitive polyimide precursor formed by adding a naphthoquinonediazide compound having a specific structure to a polyamic acid having a specific structure and subjecting it to a heat treatment at a specific temperature range after exposure (for example, a proceedings of the Society of Polymer Science, Vol. 40, No. 3, 8
21 (1991)).

However, all of these methods are complicated in the method of producing the photosensitive polyimide composition,
At present, there is a problem in performance, especially in light sensitivity, and it has not been put to practical use.

[0011]

SUMMARY OF THE INVENTION According to the present invention, a photosensitive polyimide precursor composition having good sensitivity can be obtained without using a sensitizer. It is an object of the present invention to provide a photosensitive polyimide precursor composition for i-line which has excellent performance and good film properties after imidization.

[0012]

The object of the present invention is to provide (a) a polymer (A) having a structural unit represented by the general formula (1) as a main component,

Embedded image (Where R ¹ is a trivalent or tetravalent organic group having at least 2 carbon atoms, R ² is a divalent organic group having at least 2 carbon atoms, R ³ is hydrogen, an alkali metal ion , An ammonium ion or an organic group having 1 to 30 carbon atoms. N is 1 or 2.) (b) a compound (B) having an ethylenically unsaturated double bond and an amino group, and (c) a general formula Oxime compound (C) represented by (2)

Embedded image (However, R ⁴ is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R ⁵
Is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms,
10 cycloalkyl groups, C6-C20 aryl groups, C7-C20 arylalkyl groups, C1-C1
10 aliphatic acyl group, aromatic acyl group having 6 to 20 carbon atoms, aliphatic sulfonyl group or an aliphatic sulfonyl group having 6 to 20 carbon atoms having 1 to 10 carbon atoms, R ⁶ is 1 to carbon atoms
10 alkyl groups, C 1-10 alkoxy groups, C 5-10 cycloalkyl groups, C 6-20 aryl groups, C 6-20 aryloxy groups, C 7-7
20 represents an arylalkyl group or an unsaturated hydrocarbon having 2 to 10 carbon atoms. This is achieved by a photosensitive polyimide precursor composition for i-line, which comprises:

The polymer (A) having a structural unit represented by the general formula (1) as a main component in the present invention is a polymer having an imide ring or another cyclic structure (hereinafter, referred to as a polymer) by heating or an appropriate catalyst. Polyimide-based polymer).

In the general formula (1), R ¹ is at least 2
Is a trivalent or tetravalent organic group having three carbon atoms.
From the viewpoint of heat resistance, R ¹ is preferably a trivalent or tetravalent group containing an aromatic ring or an aromatic heterocyclic ring and having 6 to 30 carbon atoms. Specific examples include, but are not limited to, phenyl, biphenyl, terphenyl, naphthalene, perylene, diphenylether, diphenylsulfone, diphenylpropane, benzophenone, and biphenyltrifluoropropane. .

In the above general formula (1), R ² is at least 2
R ² contains an aromatic ring or an aromatic heterocyclic ring from the viewpoint of heat resistance,
Further, a divalent group having 6 to 30 carbon atoms is preferable. Specific examples include, but are not limited to, phenyl, biphenyl, terphenyl, naphthalene, perylene, diphenylether, diphenylsulfone, diphenylpropane, benzophenone, and biphenyltrifluoropropane. .

Further, in order to improve the adhesion to the substrate, an aliphatic group having a siloxane structure may be copolymerized at R ¹ and R ² as long as the heat resistance is not reduced. Specifically, examples of the diamine component include those obtained by copolymerizing 1 to 10 mol% of bis (3-aminopropyl) tetramethyldisiloxane.

R ³ represents hydrogen, an alkali metal ion, an ammonium ion, or an organic group having 1 to 30 carbon atoms.
Preferred specific examples of R ³ include, but are not limited to, hydrogen, methyl, ethyl, isopropyl, butyl, ethyl methacrylate, ethyl acrylate, o-nitrobenzyl, and the like. Particularly, as R ³ , hydrogen is preferable.

In the polymer (A), R ¹ , R ² , and R ³ may be each composed of one of them,
It may be a copolymer composed of more than one kind.

The polymer (A) may be composed of only the structural unit represented by the general formula (1), or may be a copolymer or a blend with another structural unit.
At that time, 90 mol% of the structural unit represented by the general formula (1) was used.
It is preferable to contain the above. The type and amount of the structural unit used in the copolymerization or blending are preferably selected within a range that does not impair the heat resistance of the polyimide polymer obtained by the final heat treatment.

Specific examples of the polymer (A) include pyromellitic dianhydride and 4,4'-diaminodiphenyl ether
Ter, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, 3,3', 4,4'-biphenyltetracarboxylic dianhydride and 4 , 4'-diaminodiphenyl ether,
3,3 ', 4,4'-biphenyltrifluoropropanetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, 3,3', 4,4'-biphenylsulfonetetracarboxylic dianhydride And 4,4'-diaminodiphenyl ether, pyromellitic dianhydride and 3,3'-
(Or 4,4 ′) diaminodiphenylsulfone, 3,
3 ′, 4,4′-benzophenonetetracarboxylic dianhydride and 3,3 ′-(or 4,4 ′) diaminodiphenylsulfone, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride 3,3 ′-(or 4,4 ′) diaminodiphenylsulfone, pyromellitic dianhydride and 4,4′-diaminodiphenylsulfide, 3,3 ′,
4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl sulfide, 3,3 ',
4,4'-biphenyltetracarboxylic dianhydride and 4,
4'-diaminodiphenyl sulfide, 3,3 ', 4
4′-benzophenonetetracarboxylic dianhydride and paraphenylenediamine, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and paraphenylenediamine,
3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride and paraphenylenediamine, 3,3 ′,
4,4'-biphenyltrifluoropropanetetracarboxylic dianhydride and paraphenylenediamine, 3,3 ',
4,4'-biphenyltetracarboxylic dianhydride and tar
Phenyldiamine, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride and paraphenylenediamine, pyromellitic dianhydride and 3,3 ',
4,4'-benzophenonetetracarboxylic dianhydride and 3,3 '-(or 4,4') diaminodiphenyl-
Ter, pyromellitic dianhydride and 3,3 ', 4,4
'-Biphenyltetracarboxylic dianhydride and paraphenylenediamine, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether and bis (3-aminopropyl) Tetramethyldisiloxane, pyromellitic dianhydride and 4,4 '
-Diaminodiphenyl ether and bis (3-aminopropyl) tetramethyldisiloxane, 3,3 ', 4
4'-biphenyltetracarboxylic dianhydride and 4,4 '
Polyamic acids synthesized from -diaminodiphenylether and bis (3-aminopropyl) tetramethyldisiloxane, and the like, and ester compounds thereof, but are not limited thereto.

These polyamic acids and their esters are synthesized by known methods. That is, in the case of polyamic acid, tetracarboxylic dianhydride and diamine are selectively combined, and these are mainly composed of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and the like. Polar solvent, γ-
It is synthesized by reacting in butyrolactone.
Esterified polyamic acid is disclosed in, for example, JP-A-61-7.
It is synthesized by the method described in JP-A-2022 and JP-B-55-30207.

The compound (B) having an ethylenically unsaturated double bond and an amino group used in the present invention includes an organic compound having an ethylenically unsaturated double bond and an amino group and having 3 to 30 carbon atoms. preferable. Furthermore, the number of carbon atoms is 3 to 3.
An aliphatic organic compound of 0 is preferred. Examples of the organic group contained therein include, but are not limited to, a hydrocarbon group, a hydroxyl group, a carbonyl group, a carboxyl group, a urethane group, a urea group, an amide group, and the like, in addition to the amino group.

Preferred specific examples of the compound (B) having an ethylenically unsaturated double bond and an amino group include dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, N, N-dimethylamino Ethyl methacrylamide,
N, N-dimethylaminopropyl methacrylamide,
N, N-diethylaminoethyl methacrylamide, N,
N-diethylaminopropyl methacrylamide, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylaminopropyl acrylate, N, N-
Examples include, but are not limited to, dimethylaminoethylacrylamide, N, N-dimethylaminopropylacrylamide, N, N-diethylaminoethylacrylamide, N, N-diethylaminopropylacrylamide.

These compounds (B) are used alone or as a mixture of two or more.

Compound (B) is represented by 5 of all the structural units of the polymer.
%, Preferably equal to or greater than 30% and equal to or less than 5 times the equivalent of all carboxyl groups in the polymer. If the ratio is out of this range, the sensitivity is deteriorated and restrictions on development are increased.

The oxime compound (C) represented by the general formula (2) used in the present invention is used as a photoinitiator.

[0027]

Embedded image (However, R ⁴ is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R ⁵
Is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms,
10 cycloalkyl groups, C6-C20 aryl groups, C7-C20 arylalkyl groups, C1-C1
10 aliphatic acyl group, aromatic acyl group having 6 to 20 carbon atoms, aliphatic sulfonyl group or an aliphatic sulfonyl group having 6 to 20 carbon atoms having 1 to 10 carbon atoms, R ⁶ is 1 to carbon atoms
10 alkyl groups, C 1-10 alkoxy groups, C 5-10 cycloalkyl groups, C 6-20 aryl groups, C 6-20 aryloxy groups, C 7-7
20 represents an arylalkyl group or an unsaturated hydrocarbon having 2 to 10 carbon atoms. Specific examples of R ⁴ include a methyl group, an ethyl group, and n-
Propyl, isopropyl, n-butyl, t-butyl, isobutyl, n-decyl, cyclohexyl, phenyl, naphthyl, tolyl, xylyl,
Mesityl group, a 4-methoxyphenyl group, 2,4,6-trimethoxyphenyl group, a benzyl group, a 2-phenylethyl group, a hydrogen atom as R ^5, a methyl group, an ethyl group, n- propyl group, an isopropyl group , N-butyl group,
t-butyl group, isobutyl group, n-decyl group, cyclohexyl group, phenyl group, naphthyl group, tolyl group, xylyl group, mesityl group, 4-methoxyphenyl group, 2,4
6- trimethoxyphenyl group, a benzyl group, 2-phenylethyl group, a formyl group, an acetyl group, a propionyl group, a benzoyl group, mesityl group, methylsulfonyl group, ethylsulfonyl group, phenylsulfonyl group, as R ⁶ is Methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, n-decyl group, methoxy group, ethoxy group, cyclohexyl group, phenyl group, naphthyl group, tolyl group, Xylyl group, mesityl group, 4-methoxyphenyl group, 2,4,6-trimethoxyphenyl group, 4-nitrophenyl group, phenoxy group, 4-methoxyphenoxy group, 2,4,6-trimethoxyphenoxy group, benzyl Group, 2-phenylethyl group, vinyl group, allyl group, 1-
Examples include, but are not limited to, propenyl, isopropenyl, 1-butenyl, styryl, cinnamyl and the like.

Oxime compound (C) used in the present invention
As a specific example of 2- (O-acetyloxime)
-2,3-butanedione, 2- (O-propionyloxime) -2,3-butanedione, 2- (O-methoxycarbonyloxime) -2,3-butanedione, 2- (O
-Ethoxycarbonyloxime) -2,3-butanedione, 2- (O-acryloyloxime) -2,3-butanedione, 2- (O-methacryloyloxime) -2,
3-butanedione, 2- (O-cinnamoyl oxime)
-2,3-butanedione, 2- (O-benzoyloxime) -2,3-butanedione, 2- (O-4-methoxybenzoyloxime) -2,3-butanedione, 2-
(O-4-nitrobenzoyloxime) -2,3-butanedione, 3- (O-acetyloxime) -2,3-pentanedione, 3- (O-propionyloxime)-
2,3-pentanedione, 3- (O-methoxycarbonyloxime) -2,3-pentanedione, 3- (O-ethoxycarbonyloxime) -2,3-pentanedione, 3- (O-methacryloyloxime)- 2,3-pentanedione, 3- (O-benzoyloxime) -2,
3-pentanedione, 1- (O-acetyloxime)-
1,2-propanedione, 1- (O-propionyloxime) -1,2-propanedione, 1- (O-methoxycarbonyloxime) -1,2-propanedione, 1-
(O-ethoxycarbonyloxime) -1,2-propanedione, 1- (O-methacryloyloxime) -1,
2-propanedione, 1- (O-benzoyl oxime)
-1,2-propanedione, 1-phenyl-1- (O-
(Acetyl oxime) -1,2-propanedione, 1-phenyl-1- (O-propionyl oxime) -1,2-
Propanedione, 1-phenyl-1- (O-methoxycarbonyloxime) -1,2-propanedione, 1-phenyl-1- (O-ethoxycarbonyloxime)-
1,2-propanedione, 1-phenyl-1- (O-acryloyloxime) -1,2-propanedione, 1-
Phenyl-1- (O-methacryloyl oxime) -1,
2-propanedione, 1-phenyl-1- (O-cinnamoyloxime) -1,2-propanedione, 1-phenyl-1- (O-benzoyloxime) -1,2-propanedione, 1-phenyl- 1- (O-4-methoxybenzoyloxime) -1,2-propanedione, 1-phenyl-1- (O-4-nitrobenzoyloxime)-
1,2-propanedione, 1-phenyl-2- (O-benzoyloxime) -2,3-butanedione, 1-acetyl-1- (O-benzoyloxime) -1,2-propanedione, 1-benzoyl- 1- (O-benzoyloxime) -1,2-propanedione, 1-acetyl-1
-(O-ethoxycarbonyloxime) -1,2-propanedione, 1-benzoyl-1- (O-ethoxycarbonyloxime) -1,2-propanedione, 1-
(2,4,6-trimethoxybenzoyl) -1- (O-
Ethoxycarbonyloxime) -1,2-propanedione, 1-methylsulfonyl-1- (O-ethoxycarbonyloxime) -1,2-propanedione, 1-phenylsulfonyl-1- (O-ethoxycarbonyloxime) -1 , 2-propanedione, 2- (O-ethoxycarbonyloxime) -2,3-pentanedione, 2-
(O-benzoyl oxime) -2,3-pentanedione, 1-benzoyl-1- (O-benzoyl oxime)
-1,2-butanedione, 1-benzoyl-1- (O-
(Ethoxycarbonyloxime) -1,2-butanedione, 1-cyclohexyl-2- (O-ethoxycarbonyloxime) -1,2-propanedione, 1-cyclohexyl-2- (O-benzoyloxime) -1,2-propane Dione, 1-benzoyl-2-cyclohexyl-
1- (O-ethoxycarbonyloxime) ethanedione, 1-benzoyl-2-cyclohexyl-1- (O-
Benzoyl oxime) ethanedione, 1-phenyl-3
-(O-ethoxycarbonyloxime) -2,3-butanedione, 1-phenyl-3- (O-benzoyloxime) -2,3-butanedione, 1-benzoyl-3-phenyl-1- (O-ethoxycarbonyloxime )-
1,2-propanedione, 1-benzoyl-3-phenyl-1- (O-benzoyloxime) -1,2-propanedione, 1-phenyl-2- (O-acetyloxime) -1,2-propanedione , 1-phenyl-2-
(O-propionyloxime) -1,2-propanedione, 1-phenyl-2- (O-methoxycarbonyloxime) -1,2-propanedione, 1-phenyl-2-
(O-ethoxycarbonyloxime) -1,2-propanedione, 1-phenyl-2- (O-acryloyloxime) -1,2-propanedione, 1-phenyl-2-
(O-methacryloyl oxime) -1,2-propanedione, 1-phenyl-2- (O-cinnamoyl oxime) -1,2-propanedione, 1-phenyl-2-
(O-benzoyloxime) -1,2-propanedione, 1-phenyl-2- (O-4-methoxybenzoyloxime) -1,2-propanedione, 1-phenyl-
2- (O-4-nitrobenzoyloxime) -1,2-
Propanedione, 1,2-diphenyl-1- (O-propionyloxime) -1,2-ethadione, 1,2-diphenyl-1- (O-ethoxycarbonyloxime)-
1,2-ethadione, 1,2-diphenyl-1- (O-
(Methacryloyl oxime) -1,2-ethadione, 1,
2-diphenyl-1- (O-benzoyloxime)-
1,2-ethadione, 1,3-diphenyl-2- (O-
Benzoyloxime) -1,2-propanedione, 1-
Phenyl-2-acetyl-2- (O-benzoyloxime) ethanedione, 1-phenyl-2-acetyl-2-
(O-ethoxycarbonyloxime) ethanedione, 1
-Phenyl-2-benzoyl-2- (O-benzoyloxime) ethanedione, 1-phenyl-2-benzoyl-2- (O-ethoxycarbonyloxime) ethanedione, 1-phenyl-2-phenylsulfonyl-2-
(O-benzoyloxime) ethanedione, 1-phenyl-2-phenylsulfonyl-2- (O-ethoxycarbonyloxime) ethanedione, 1-mesityl-2-
(O-acetyloxime) -1,2-propanedione,
1-mesityl-2- (O-propionyloxime)-
1,2-propanedione, 1-mesityl-2- (O-methoxycarbonyloxime) -1,2-propanedione, 1-mesityl-2- (O-ethoxycarbonyloxime) -1,2-propanedione, -Mesityl-2-
(O-acryloyloxime) -1,2-propanedione, 1-mesityl-2- (O-methacryloyloxime) -1,2-propanedione, 1-mesityl-2-
(O-cinnamoyl oxime) -1,2-propanedione, 1-mesityl-2- (O-benzoyl oxime)-
1,2-propanedione, 1-mesityl-2- (O-4
-Methoxybenzoyloxime) -1,2-propanedione, 1-mesityl-2- (O-4-nitrobenzoyloxime) -1,2-propanedione, and the like, but are not limited thereto. These oxime compounds (C) are used alone or as a mixture of two or more. Further, a photoinitiator other than these oxime compounds (C) may be contained as long as the effects of the present invention are not impaired.

The amount of the photoinitiator is from 1% by weight to the polymer.
100% by weight, preferably 2% to 50% by weight, more preferably 5% to 20% by weight is desirable. Deviating from this range will lower the sensitivity,
There are many restrictions on development.

As a photoreactive monomer in the composition of the present invention,
The addition of monomers such as 2-hydroxyethyl methacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and ethylene glycol dimethacrylate in an amount of 1% by weight to 20% by weight based on the polymer can further improve sensitivity.

The photosensitive polyimide precursor composition is obtained by mixing the above polymer (A), compound (B), oxime compound (C) and, if necessary, a photoreactive monomer with a solvent. As the solvent used at this time,
Polar solvents mainly containing N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide and the like, and solvents such as γ-butyrolactone, N, N-dimethylacrylamide and the like. It is preferably used alone or as a mixture of two or more, but is not limited thereto.

Further, if necessary, a surfactant for improving the wettability with the substrate, SiO ₂ ,
Inorganic particles such as TiO ₂ or polyimide particles may be added.

The composition of the present invention is for i-line (365n
It is most suitable for pattern exposure in m), in which case it is not necessary to use a sensitizer. G-line (436n ) such as 3,3'-carbonylbis (diethylaminocoumarin)
Use of a sensitizer used for pattern exposure in m) is not preferred because exposure to i-rays rather reduces the polyimide film after curing.

Next, a method for forming a polyimide pattern using the photosensitive polyimide precursor composition of the present invention will be described.

The photosensitive polyimide precursor composition is applied on a substrate. As the substrate, silicon, alumina ceramic, glass ceramic, aluminum nitride, a substrate on which a semiconductor is formed, or the like is used, but the substrate is not limited thereto. Examples of the coating method include methods such as spin coating using a spinner, spray coating, dipping, and roll coating, but are not limited thereto. The coating thickness varies depending on the coating means, the solid content concentration of the composition, the viscosity, and the like, but is usually applied so that the dried film thickness is 0.1 to 150 μm.

Next, the substrate coated with the polyimide precursor composition is dried to obtain a polyimide precursor composition film. The drying is preferably performed in an oven, a hot plate, an infrared ray or the like at 50 to 100 ° C. for 1 minute to several hours.

Next, a mask having a desired pattern is placed on this film, and the film is exposed to actinic radiation through the mask. Actinic rays used for exposure include ultraviolet rays, visible rays, electron beams, X-rays and the like. Particularly, ultraviolet rays and visible rays are preferable, and i-line of a mercury lamp is more preferably used.

The formation of a negative polyimide pattern is achieved by removing the unexposed portions using a developing solution after exposure. As a developing solution, N-methyl-2
-Pyrrolidone, N, N-dimethylacetamide, N, N
-Polar solvents such as dimethylformamide, methanol, ethanol, isopropyl alcohol, xylene,
A developer in combination with water or the like can be used. After development
Rinse with alcohol such as ethanol or isopropyl alcohol.

In order to form a positive polyimide pattern, it is important to apply a treatment in which the unexposed portion of the film after exposure has a higher degree of curing than the exposed portion, and to select a developer composition. . Heat treatment, infrared irradiation treatment, microwave irradiation treatment, and the like are effective as treatments in which the coating in the unexposed portion has a higher degree of curing than the coating in the exposed portion, and is particularly desirable in that the heat treatment is simple. The heat treatment is preferably performed at a temperature equal to or higher than the drying step for one minute to several hours. Specifically, the temperature is 60 to 180 ° C, more preferably 90 to 170 ° C. By performing these treatments after exposure, the unexposed film has a higher degree of curing than the exposed film, and the resistance to the developer causes a difference between the unexposed film and the exposed film. . If the unexposed portion has a higher resistance to the developing solution than the exposed portion, the exposed portion is removed faster than the unexposed portion, and a positive image is formed. In the opposite case, that is, when the exposed portion has higher resistance to the developing solution than the unexposed portion, the unexposed portion is removed faster than the exposed portion, and a negative image is formed. .

The term “curing” as used herein means that components other than polyimide, for example, a compound having an amino group, a photoinitiator, photoreactive monomers, a solvent, and ring-closing water are volatilized from a polyimide precursor film. Say. As the curing of the polyimide precursor composition progresses, the film thickness becomes thinner, and the film thickness becomes constant when curing is completed, that is, when the polyimide film is formed. The difference in the degree of cure between the unexposed portion and the exposed portion after the treatment to increase the degree of cure is determined by the film thickness ratio, that is, (curing degree ratio = film thickness of unexposed portion film thickness ÷
(Thickness of the exposed portion film). The curing degree ratio depends on the exposure dose and the processing conditions for promoting curing, but is preferably 0.98 or less in order to form a positive polyimide pattern.

As a developer suitable for forming a positive polyimide pattern, an alkali aqueous solution such as sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline is most desirable. Also, N-
An organic solvent-based developer in which a polar solvent such as methyl-2-pyrrolidone or N, N-dimethylacetamide is combined with methanol, ethanol, isopropyl alcohol, xylene, water, etc., depends on the components of the photosensitive polyimide precursor composition. Gives a positive, or negative image. After development, it is rinsed with water or an alcohol such as methanol, ethanol or isopropyl alcohol.

After development, a polyimide insulating film is obtained by curing. After the development, select the temperature and raise the temperature stepwise or select a certain temperature range while continuously raising the temperature.
Perform for minutes to 5 hours. The maximum temperature of this cure is 250
To 500 ° C., preferably 300 to 450 ° C. For example, at 130 ° C., 200 ° C., and 400 ° C., 3
Heat treatment for 0 minutes. Alternatively, the temperature may be raised linearly from room temperature to 400 ° C. over 2 hours.

The polyimide film formed from the photosensitive polyimide precursor according to the present invention is used as a passivation film for a semiconductor, a protective film for a semiconductor element, or an interlayer insulating film for a multilayer wiring for high-density mounting.

[0044]

EXAMPLES Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

Example 1 80.55 g of 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride and 54.53 g of pyromellitic dianhydride were added to 2.3 g of ethanol and 549 g of N-methyl-2-pyrrolidone.
, And reacted at 70 ° C. for 3 hours. Thereafter, the mixture is cooled to 20 ° C. and 95.10 g of 4,4′-diaminodiphenyl ether
Then, 6.20 g of bis (3-aminopropyl) tetramethyldisiloxane was added, and further reacted at 60 ° C. for 3 hours to obtain a polymer solution of the structural unit (1) having a viscosity of 126 poise (25 ° C.). To this solution, 157.2 g of dimethylaminoethyl methacrylate (equivalent to all carboxyl groups in the polymer), 1-phenyl-2- (O-benzoyloxime)
23.6 g of -1,2-propanedione and 315 g of γ-butyrolactone were added to obtain a photosensitive polyimide precursor composition.

This photosensitive polyimide precursor composition was coated on a 4-inch silicon wafer and dried in a nitrogen atmosphere at 60 ° C. for 30 minutes to form a photosensitive polyimide precursor film having a thickness of 4.36 μm. UV exposure machine PL manufactured by Canon Inc.
A-501F was fitted with a filter, and exposed to i-line only through a chrome photomask at 500 mJ / cm ² . After the exposure, heat treatment was performed on a hot plate at 140 ° C. for 3 minutes. Due to this treatment, the unexposed film is 3.60 μm,
The film thickness of the exposed portion was 3.72 μm (curing ratio 0.968), and a difference was observed between the unexposed portion and the exposed portion. Next, when the film was immersed in a developing solution composed of a 2.38% aqueous solution of tetramethylammonium hydroxide, the exposed portion was dissolved, and an image having an unexposed portion remaining of 3.02 μm was formed. After rinsing with water, it was dried by blowing nitrogen. The positive pattern thus obtained was applied at 130 ° C, 200 ° C, 400 ° C
Each was cured in a nitrogen atmosphere for 30 minutes to form a good positive type polyimide pattern.

Comparative Example 1 The procedure of Example 1 was repeated, except that 1-phenyl-2- (O-benzoyloxime) -1,2-propanedione was not added. A body composition was obtained.

This photosensitive polyimide precursor composition was coated on a 4-inch silicon wafer and dried in a nitrogen atmosphere at 60 ° C. for 30 minutes to form a photosensitive polyimide precursor film having a thickness of 4.15 μm. UV exposure machine PL manufactured by Canon Inc.
A-501F was fitted with a filter, and exposed to i-line only through a chrome photomask at 500 mJ / cm ² . After the exposure, heat treatment was performed on a hot plate at 140 ° C. for 3 minutes. This treatment did not produce any measurable difference in the film thickness of the unexposed and exposed areas. (Curing degree ratio ~ 1.0
00). Next, when immersed in a developing solution consisting of a 2.38% aqueous solution of tetramethylammonium hydroxide, there was no difference in solubility between exposed and unexposed portions, and no polyimide pattern was obtained at all.

Comparative Example 2 In Example 1, benzoin ethyl ether known as a photopolymerization initiator was used in place of 1-phenyl-2- (O-benzoyloxime) -1,2-propanedione.
The same operation as in Example 1 was performed except that 23.6 g was used, to obtain a photosensitive polyimide precursor composition.

This photosensitive polyimide precursor composition was coated on a 4-inch silicon wafer and dried in a nitrogen atmosphere at 60 ° C. for 30 minutes to form a photosensitive polyimide precursor film having a thickness of 4.61 μm. UV exposure machine PL manufactured by Canon Inc.
A-501F was fitted with a filter, and exposed to i-line only through a chrome photomask at 500 mJ / cm ² . After the exposure, heat treatment was performed on a hot plate at 140 ° C. for 3 minutes. By this treatment, the film of the unexposed part is 3.71 μm,
The film thickness of the exposed part was 3.77 μm (curing degree ratio 0.984), and no significant difference was observed between the unexposed part and the exposed part. Next, when immersed in a developing solution consisting of a 2.38% aqueous solution of tetramethylammonium hydroxide, there was no difference in solubility between exposed and unexposed portions, and a clear polyimide pattern could not be obtained.

Example 2 The procedure of Example 1 was repeated, except that the developer consisting of a 2.38% aqueous solution of tetramethylammonium hydroxide was replaced with N-
The film was immersed in a developer composed of 900 g of methyl-2-pyrrolidone and 100 g of water, rinsed with isopropyl alcohol, and then blown with nitrogen to obtain a negative pattern.

Example 3 The photosensitive polyimide precursor obtained in Example 1 was coated on a 4-inch silicon wafer, dried at 80 ° C. for 30 minutes in a nitrogen atmosphere, and then heated at 130 ° C., 200 ° C., and 400 ° C. for 30 minutes each.
Curing was performed in a nitrogen atmosphere to obtain a polyimide film having a thickness of 5.60 μm. This film was peeled off from the silicon wafer, cut into strips having a width of 1 cm, and the elongation was measured by a tensile tester. As a result, strength 13.5 kg / mm ² ,
A value of elongation of 25% was obtained, indicating that a strong polyimide film was obtained.

Comparative Example 3 157.2 g (equivalent to all carboxyl groups in the polymer) of dimethylaminoethyl methacrylate was added to a polymer solution of the structural unit (1) obtained in Example 1 and 1-phenyl-2- (O
-Benzoyloxime) -1,2-propanedione 23.
6 g, 11.8 g of 3,3′-carbonylbis (diethylaminocoumarin) as a sensitizer and γ-butyrolactone
315 g was added to obtain a photosensitive polyimide precursor composition. This photosensitive polyimide precursor was coated on a 4-inch silicon wafer, dried at 80 ° C. for 30 minutes in a nitrogen atmosphere, and then cured at 130 ° C., 200 ° C., and 400 ° C. for 30 minutes each in a nitrogen atmosphere to a thickness of 5.71. A μm polyimide coating was obtained. The coating was peeled off from the silicon wafer, cut into strips having a width of 1 cm, and the elongation was measured with a tensile tester. As a result, values of strength 6.4 kg / mm ² and elongation of 4% were obtained, and it was found that the physical properties of the polyimide film were reduced by the addition of the sensitizer.

Example 4 In Example 1, 1-phenyl-2- (O-benzoyloxime) -1,2-propanedione was replaced by 1
-Mesityl-2- (O-benzoyloxime) -1,2
Example 1 was repeated except that propanedione was used to obtain a photosensitive polyimide precursor composition.

The photosensitive polyimide precursor composition was coated on a 4-inch silicon wafer and dried at 60 ° C. for 30 minutes in a nitrogen atmosphere to form a 4.61 μm-thick photosensitive polyimide precursor film. UV exposure machine PL manufactured by Canon Inc.
A-501F was fitted with a filter, and exposed to i-line only through a chrome photomask at 500 mJ / cm ² . After the exposure, heat treatment was performed on a hot plate at 140 ° C. for 3 minutes. By this treatment, the film of the unexposed part is 3.71 μm,
The film thickness of the exposed part was 3.92 μm (hardness ratio 0.946), and a difference was observed between the unexposed part and the exposed part. Next, when the film was immersed in a developing solution composed of a 2.38% aqueous solution of tetramethylammonium hydroxide, the exposed portion was dissolved, and an image having an unexposed portion remaining at 3.15 μm was formed. After rinsing with water, it was dried by blowing nitrogen. The positive pattern thus obtained was applied at 130 ° C, 200 ° C, 400 ° C
Each was cured in a nitrogen atmosphere for 30 minutes to form a good positive type polyimide pattern.

[0056]

As described above, the present invention provides a polymer having a structural unit represented by the general formula (1) as a main component, a compound having an ethylenically unsaturated double bond and an amino group,
It was possible to obtain an unexpected effect that the composition containing the oxime compound represented by the general formula (2) exhibits excellent performance as a positive type or negative type photosensitive polyimide precursor for i-line. Things. The photosensitive polyimide precursor composition of the present invention can be easily produced, and cured after development to obtain a polyimide film having excellent strength and elongation.

Continuation of the front page (51) Int.Cl. ⁶ identification code FI G03F 7/039 501 G03F 7/039 501 H01L 21/027 H01L 21/30 502R (56) References JP-A-60-42425 (JP, A) JP-A-63-256663 (JP, A) JP-A-63-99235 (JP, A) JP-A-54-145794 (JP, A) JP-A-3-91752 (JP, A) JP-A-62-273259 (JP, A) JP-A-62-127840 (JP, A) JP-A-62-184056 (JP, A) JP-A-61-118423 (JP, A) JP-A-6-324492 (JP, A) 45-28383 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03F 7/038 C08K 5/17 C08K 5/33 C08L 79/08 G03F 7/037 G03F 7/039

Claims (3)

(57) [Claims] (A) a polymer (A) having a structural unit represented by the general formula (1) as a main component, (Where R ¹ is a trivalent or tetravalent organic group having at least 2 carbon atoms, R ² is a divalent organic group having at least 2 carbon atoms, R ³ is hydrogen, an alkali metal ion , An ammonium ion or an organic group having 1 to 30 carbon atoms. N is 1 or 2.) (b) a compound (B) having an ethylenically unsaturated double bond and an amino group, and (c) a general formula Oxime compound (C) represented by (2) (However, R ⁴ is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R ⁵
Is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms,
10 cycloalkyl groups, C6-C20 aryl groups, C7-C20 arylalkyl groups, C1-C1
10 aliphatic acyl group, aromatic acyl group having 6 to 20 carbon atoms, aliphatic sulfonyl group or an aliphatic sulfonyl group having 6 to 20 carbon atoms having 1 to 10 carbon atoms, R ⁶ is 1 to carbon atoms
10 alkyl groups, C 1-10 alkoxy groups, C 5-10 cycloalkyl groups, C 6-20 aryl groups, C 6-20 aryloxy groups, C 7-7
20 represents an arylalkyl group or an unsaturated hydrocarbon having 2 to 10 carbon atoms. And i) a photosensitive polyimide precursor composition for i-line. 2. The compound (B) having an ethylenically unsaturated double bond and an amino group accounts for 30% of the polymer (A) having a structural unit represented by the general formula (1) as a main component. 2. The mixture according to claim 1, wherein the equivalent is not less than 5 equivalents of all carboxyl groups in the polymer.
The photosensitive polyimide precursor composition for i-line according to the above. 3. A compound (B) having an ethylenically unsaturated double bond and an amino group, comprising dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, N, N-dimethylaminoethyl methacrylamide, N, N-dimethylaminopropyl methacrylamide, N, N-diethylaminoethyl methacrylamide, N, N-diethylaminopropyl methacrylamide, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylaminopropyl acrylate, N, N-dimethyl Aminoethylacrylamide, N, N-dimethylaminopropylacrylamide, N, N-diethylaminoethylacrylamide,
The photosensitive polyimide precursor composition for i-line according to claim 1 or 2, wherein the composition is at least one member selected from the group consisting of N, N-diethylaminopropylacrylamide.