JP2000147761A - Photosensitive polyimide composition and pattern forming method by using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the photosensitive composition capable of developing in a short time with an aqueous solution and low in tendency to cause swelling in exposed areas at the time of development and high in resolution by making a first polyimide having specified first repeating units react with an isocyanate compound having a C=C double bond. SOLUTION: The photosensitive polyimide composition is obtained by making the first polyimide, which has the first repeating unit represented by the formula, react with the isocyanate compound having the C=C double bond. In the formula, R1 is an organic group having a tetravalent organic group having >=4C; R2 is a tri- or tetra-valent organic group having an aromatic ring; A1 is a carboxyl group or a phenolic hydroxyl group; and (n) is 1 or 2. The bonding system between the first polyimide and the isocyanate compound may be ion bond or coordination bond, however, covalent bond, especially amide bond and urethane bond are preferable from the viewpoints of the stability of the compound and the film characteristics finally obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive material suitable for a protective film such as a surface coat film of a semiconductor device and an interlayer insulating film of a thin film multilayer wiring board.
The present invention relates to a photosensitive polyimide composition and a negative photosensitive material containing the same, a method for forming a resin pattern, and a method for producing a photosensitive polyimide.

[0002]

2. Description of the Related Art Conventionally, as a photosensitive heat-resistant material for obtaining a heat-resistant polymer, an aromatic tetracarboxylic dianhydride described in JP-B-5-67026 is reacted with an olefinically unsaturated alcohol. To obtain an olefin aromatic tetracarboxylic acid diester, polymerize this compound and a diamine by a dehydration condensation reaction using carbodiimide, and introduce a photosensitive group through a covalent bond, and
No. 63-31939, a polyamic acid obtained by reacting an aromatic tetracarboxylic dianhydride with an aromatic diamine is reacted with an amine compound having a photosensitive group, and a photosensitive group is introduced by ionic bonding. Is known.

[0003] In each of these prior arts, a varnish dissolved in an appropriate organic solvent is applied to a substrate and dried to form a film. By curing, developing and rinsing with an organic solvent, a negative relief pattern is obtained.

However, when an organic solvent is used as a developing solution at the time of pattern formation, swelling of an exposed portion is likely to occur at the time of development, and it is difficult to obtain a high-resolution pattern. In addition, when an organic solvent is used, there is a problem that the health of a worker is adversely affected and a waste liquid treatment is troublesome.

Therefore, in order to solve the above problems,
As a material that can be developed with an aqueous liquid, for example, a positive polymer in which a naphthoquinonediazidosulfonylamide group is introduced into a carboxyl group of a polyamic acid has been proposed (JP-A-6-258835). This polymer is characterized in that a naphthoquinonediazidosulfonylamide group is changed into a carboxyl group by light irradiation, so that the exposed part is solubilized in a basic aqueous solution, and is used as a positive photosensitive material.

However, this positive type photosensitive material has a problem that sufficient sensitivity cannot be obtained when a long time is required for development or when a thick (10 μm or more) film is formed.

Therefore, the present inventors have solved the above-mentioned problems, and have developed a polyimide precursor for providing a high-resolution photosensitive material that can be developed in a short time with an aqueous solution and that does not easily cause swelling of an exposed portion during development. The following general formula (Formula 1)
A compound having a repeating unit represented by 1) was found.

[0008]

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(However, R ⁹ is a group containing 4 or more carbon atoms.
A valent organic group, R ¹⁰ is a trivalent or tetravalent organic group containing an aromatic ring, R ¹¹ is a monovalent organic group, A ² is an acidic monovalent group, and n is 1 or 2. ) The polyimide precursor, because it has a group A ² acidic in the structural unit of the polymer, before curing well dissolved in a basic aqueous solution. Therefore, development can be easily carried out with a basic aqueous solution, and the above-mentioned various problems caused by using an organic solvent as a developer can be overcome.

If R ¹¹ is a photosensitive group, this polyimide precursor can be used as a negative photosensitive polyimide precursor which is cured by exposure. In this case, since the photosensitive group is introduced by an ester bond, a thick film (10
(μm or more), the curability of the exposed portion is excellent, and if this polyimide precursor is used, a negative pattern can be formed in a short development time.

[0011]

However, since the polyimide precursor is cured by exposing and developing the polyimide by closing the imide ring after exposure and development, a dehydration reaction for ring closure occurs at the time of curing. Therefore, in this polyimide precursor, due to volume shrinkage due to dehydration reaction,
There is a problem that loss of film thickness and reduction of dimensional accuracy are caused.

Accordingly, the present invention provides a photosensitive polyimide which can form an insulating film without causing such a loss in film thickness and a decrease in dimensional accuracy, and which can be developed in a short time with an aqueous solution. An object of the present invention is to provide a method for producing a compound, a polyimide composition and a photosensitive material containing the compound, and a method for forming a resin pattern using the same.

[0013]

In order to achieve the above object, the present invention provides a first polyimide having a first repeating unit represented by the following general formula (Chemical Formula 1) and a carbon-carbon double bond. A photosensitive polyimide obtained by reacting with an isocyanate compound having the formula: The weight average molecular weight of the photosensitive polyimide of the present invention is preferably from 10,000 to 200,000, and more preferably from 20,000 to 100,000.

[0014]

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In the general formula (Chemical Formula 1), R ¹ is a tetravalent organic group containing four or more carbon atoms, R ² is a trivalent or tetravalent organic group containing an aromatic ring, and A ¹ is a carboxyl group. Group or phenolic hydroxyl group, n is 1 or 2.

The type of bonding between the first polyimide and the isocyanate compound is not particularly limited, and may be an ionic bond or a coordinate bond. It is preferable in terms of properties and finally obtained film properties. These bonds are
Since the bond energy is lower than that of other covalent bonds such as an ester bond, the photosensitive group is easily detached by heating during film formation. Therefore, the obtained film characteristics are good.

Accordingly, in the present invention, the following general formula (Formula 4)
A photosensitive polyimide having a third repeating unit represented by the formula:

[0018]

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However, in the general formula (Formula 4), R ⁵ ,
R ⁶ and R ⁷ are each independently selected from hydrogen, an alkyl group having 1 to 5 carbon atoms, an aromatic group having 5 to 30 carbon atoms, and an alkenyl group having 1 to 5 carbon atoms,
R ⁸ represents a divalent organic group.

Since the photosensitive polyimide of the present invention already has a ring-closed imide structure, curing shrinkage due to heating is small and pattern dimensional stability is high. further,
An acidic group A ¹ in the structural unit of the polyimide or an —CONH— bond or —O
Since it has a CONH- group, it dissolves well in a basic aqueous solution. Therefore, the photosensitive polyimide of the present invention can be easily developed with a basic aqueous solution. In addition, the photosensitive polyimide of the present invention is excellent in curability of an exposed portion because a photosensitive group which is crosslinked by exposure is introduced into a molecule by a covalent bond. Therefore, the unexposed portion has the property of dissolving in a basic aqueous solution, hardening by exposure and insolubilizing in the basic aqueous solution, and can form a negative pattern in a short development time.

[0021] Incidentally, as a raw material of the photosensitive polyimide, a first polyimide may not be provided with acidic groups A ¹ to all of the repeating units, the acidic group A ¹ to 10 mol% of the repeating units I just need. That is, a copolymer having a second repeating unit represented by the following general formula (Formula 2) in addition to the first repeating unit may be used.

Similarly, the photosensitive polyimide of the present invention does not need to have a photosensitive group R ¹⁰ in all repeating units, and it is sufficient that at least 10 mol% of repeating units have an acidic group R ¹⁰ . That is, a copolymer having a second repeating unit represented by the following general formula (Formula 2) in addition to the third repeating unit may be used.

[0023]

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(Wherein, R ³ is a tetravalent organic group containing four or more carbons, and R ⁴ is a divalent organic group containing an aromatic ring or silicon.) When used, the copolymerization ratio of these repeating units may be the first or third assuming that the total of the number of first or third repeating units and the number of second repeating units in one molecule is 100. The number of repeating units is 10 or more and 100
Hereinafter, it is desirable that the number of the second repeating units is 0 or more and 90 or less.

Also, in the present invention, a photosensitive polyimide composition comprising 100 parts by weight of the photosensitive polyimide of the present invention, 0.1 to 50 parts by weight of a sensitizer, and 0.1 to 50 parts by weight of a photopolymerization auxiliary is used. A method for forming a resin pattern using the photosensitive polyimide composition includes irradiating a film made of the above-described photosensitive polyimide composition with light through a mask having a predetermined pattern. And a method for forming a resin pattern comprising a step of developing the coating film by using the method.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The first polyimide which is a raw material of the photosensitive polyimide of the present invention has, for example, the following general formula (Chemical Formula 1)
2) an acid dianhydride represented by the following general formula:
It is obtained by reacting the diamine represented by 3) in a solvent, heating to 150 ° C. or more in the presence of an amine and an acid catalyst, and performing dehydration ring-closing imidization.

[0027]

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[0028]

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In the diamine component, the compound represented by the above general formula (Formula 13) may be 10 mol% or more, and 90 mol% or less of the total diamine component is represented by the following general formula (Formula 14). A mixture of the diamine represented by formula (I) and 10 mol% or more of the diamine represented by the general formula (Formula 13)
A copolymer obtained by polymerizing with the acid dianhydride of the above general formula (Formula 12) can also be used as a raw material of the photosensitive polyimide of the present invention.

[0030]

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The acidic group A ¹ contained in this polyimide is
It is a carboxyl group or a phenolic hydroxyl group. The diamine residue R ² to which the acidic group A ¹ is bonded is a trivalent or tetravalent organic compound containing an aromatic ring from the viewpoint of the mechanical properties, heat resistance, and adhesiveness of the polyimide film obtained by curing. Group. Preferred examples thereof are shown in the following structural formula group (Formula 7). Note that all R ² in the molecule may be the same, or different groups R ² may be mixed in the molecule.

[0032]

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The diamine residue R ⁴ of the second repeating unit (formula 2) in which the acidic group A ¹ does not exist is obtained from the viewpoints of mechanical properties, heat resistance and adhesiveness of the polyimide film obtained by curing. It is a divalent organic group containing an aromatic ring and / or silicon. Preferred examples thereof are shown in the following structural formula groups (Chem. 8), (Chem. 9), and (Chem. 10). Note that all R ⁴ in the molecule may be the same, and different groups R ⁴
May be present in the molecule.

[0034]

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[0035]

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[0036]

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In the general formulas (1), (2) and (4) of the photosensitive polyimide of the present invention, R ¹ and R ³
Is a tetravalent organic group having 4 or more carbon atoms from the viewpoint of mechanical properties, heat resistance, and adhesiveness of the polyimide film obtained by curing. The preferred examples are represented by the following structural formula group (Chemical Formula 6)
Listed in Note that all R ¹ R ³ in the molecule may be the same, or different groups R ¹ or R ³ may be mixed in the molecule. Among them, those having a biphenyl skeleton,
In addition, those having a diphenyl ether skeleton are preferable because when the pattern is formed using polyimide having photosensitivity, the shape of the pattern is good.

[0038]

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The photosensitive polyimide of the present invention can be synthesized, for example, by reacting the above-mentioned first polyimide with an isocyanate compound having a carbon-carbon double bond.

As the isocyanate compound, it is desirable to use a compound represented by the following general formula (Formula 3).
When this compound is used, a group represented by the following general formula (Formula 5) can be introduced into the polyimide through an amide bond or a urethane bond, and a high-resolution photosensitive polyimide can be obtained.

[0041]

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(Wherein, R ⁵ , R ⁶ and R ⁷ are each independently selected from hydrogen, an alkyl group, a phenyl group, a vinyl group and a propenyl group, and R ⁸ is 2
It shows a valent organic group. )

[0043]

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(Wherein R ⁵ , R ⁶ and R ⁷ are hydrogen, an alkyl group having 1 to 5 carbon atoms, an aromatic group having 5 to 30 carbon atoms, or an alkenyl group having 1 to 5 carbon atoms) And R ⁸ represents a divalent organic group. Specific examples of preferable isocyanate compounds include isocyanate ethyl methacrylate, isocyanate ethyl acrylate, and isocyanate propyl methacrylate. However, the present invention is not limited to these. One type of isocyanate compound may be used, or a mixture of several types may be used.

In synthesizing the photosensitive polyimide of the present invention, the isocyanate compound is preferably added in an amount of 0.1 to 400 parts by weight, and more preferably 1 to 200 parts by weight, based on 100 parts by weight of the first polyimide. More preferred.

As described above, the photosensitive polyimide composition of the present invention is used as a negative photosensitive material in which exposed portions are cured, and is used as a protective film such as a surface coat film of a semiconductor device or an interlayer insulating film of a thin film multilayer wiring board. Suitable for films and the like. The components other than the photosensitive polyimide and the isocyanate compound of the photosensitive polyimide composition of the present invention are described below.

The photosensitive polyimide composition of the present invention preferably contains a sensitizer in order to further improve the exposure sensitivity. Preferred examples of the sensitizer include Michler's ketone, bis-4,4'-diethylaminobenzophenone, benzophenone, 3,5-bis (diethylaminobenzylidene) -N-methyl-4-piperidone, 3,5-bis (dimethylaminobenzylidene) ) -N-Methyl-4-piperidone, 3,5-bis (diethylaminobenzylidene)-
N-ethyl-4-piperidone, 3,3'-carbonylbis (7-diethylamino) coumarin, riboflavin tetrabutyrate, 2-methyl-1- [4- (methylthio)
Phenyl] -2-morpholinopropan-1-one,
2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 3,5-dimethylthioxanthone, 3,5-diisopropylthioxanthone, 1-phenyl-2- (ethoxycarbonyl) oxyiminopropane-1 -One, benzoin ether, benzoin isopropyl ether, benzanthrone, 5-nitroacenaphthene, 2-nitrofluorene, anthrone, 1,2-benzanthraquinone, 1-phenyl-5-mercapto-1H-tetrazole, thioxanthen-9- ON, 10-thioxanthenone, 3-acetylindole, 2,6-di (p-dimethylaminobenzal) -4-carboxycyclohexanone, 2,6-di (p-dimethylaminobenzal) -4-
Hydroxycyclohexanone, 2,6-di (p-diethylaminobenzal) -4-carboxycyclohexanone, 2,6-di (p-diethylaminobenzal) -4-
Hydroxycyclohexanone, 4,6-dimethyl-7-
Ethylaminocoumarin, 7-diethylamino-4-methylcoumarin, 7-diethylamino-3- (1-methylbenzimidazolyl) coumarin, 3- (2-benzimidazolyl) -7-diethylaminocoumarin, 3- (2-benzothiazolyl) -7- Diethylaminocoumarin, 2-
(P-dimethylaminostyryl) benzoxazole,
2- (p-dimethylaminostyryl) quinoline, 4-
(P-dimethylaminostyryl) quinoline, 2- (p-
Dimethylaminostyryl) benzothiazole, 2- (p
-Dimethylaminostyryl) -3,3-dimethyl-3H
-Indole and the like, but are not limited thereto.

The sensitizer is preferably added in an amount of 0.1 to 50 parts by weight, more preferably 0.3 to 20 parts by weight, based on 100 parts by weight of the photosensitive polyimide contained in the present invention. Deviating from the range of 0.1 to 50 parts by weight,
The sensitizing effect may not be obtained, or the developing property may be unfavorably affected. As the sensitizer, one type of compound may be used, or a mixture of several types may be used.

The photosensitive polyimide composition of the present invention may further contain a photopolymerization aid for further improving the exposure sensitivity. As the photopolymerization auxiliary, for example,
4-diethylaminoethyl benzoate, 4-dimethylaminoethyl benzoate, 4-diethylaminopropyl benzoate, 4-dimethylaminopropyl benzoate, 4-dimethylaminoisoamyl benzoate, N
-Phenylglycine, N-methyl-N-phenylglycine, N- (4-cyanophenyl) glycine, 4-dimethylaminobenzonitrile, ethylene glycol dithioglycolate, ethylene glycol di (3-mercaptopropionate), trimethylol Propanethioglycolate, trimethylolpropanetri (3-mercaptopropionate), pentaerythritol tetrathioglycolate, pentaerythritoltetra (3-mercaptopropionate), trimethylolethanetrithioglycolate, trimethylolpropanetrithio Glycolate, trimethylolethane tri (3-mercaptopropionate), dipentaerythritol hexa (3-mercaptopropionate), thioglycolic acid, α-mercaptopropion Acid, t- butyl peroxybenzoate, t- butyl peroxy-methoxybenzoate, t
-Butylperoxynitrobenzoate, t-butylperoxyethylbenzoate, phenylisopropylperoxybenzoate, di-tert-butyldiperoxyisophthalate, tri-tert-butyltriperoxytrimellitate, tri-tert-butyltriperoxytrimesitate,
Tetra-t-butyltetraperoxypyromellitate,
2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 3,3 ′,
4,4'-tetra (t-amylperoxycarbonyl)
Benzophenone, 3,3 ′, 4,4′-tetra (t-hexylperoxycarbonyl) benzophenone, 2,6-
Di (p-azidobenzal) -4-hydroxycyclohexanone, 2,6-di (p-azidobenzal) -4-carboxycyclohexanone, 2,6-di (p-azidobenzal) -4-methoxycyclohexanone, 2,6-di ( p-azidobenzal) -4-hydroxymethylcyclohexanone, 3,5-di (p-azidobenzal) -1-
Methyl-4-piperidone, 3,5-di (p-azidobenzal) -4-piperidone, 3,5-di (p-azidobenzal) -N-acetyl-4-piperidone, 3,5-di (p-azidobenzal) -N-methoxycarbonyl-4
-Piperidone, 2,6-di (p-azidobenzal) -4
-Hydroxycyclohexanone, 2,6-di (m-azidobenzal) -4-carboxycyclohexanone, 2,
6-di (m-azidobenzal) -4-methoxycyclohexanone, 2,6-di (m-azidobenzal) -4-hydroxymethylcyclohexanone, 3,5-di (m-azidobenzal) -N-methyl-4-piperidone, 3,5
-Di (m-azidobenzal) -4-piperidone, 3,5
-Di (m-azidobenzal) -N-acetyl-4-piperidone, 3,5-di (m-azidobenzal) -N-methoxycarbonyl-4-piperidone, 2,6-di (p-azidocinnamylidene)- 4-hydroxycyclohexanone, 2,6-di (p-azidocinnamylidene) -4-carboxycyclohexanone, 2,6-di (p-azidocinnamylidene) -4-hydroxymethylcyclohexanone, 3,5-di ( p-azidocinnamylidene) -N-methyl-4-piperidone, 4,4'-diazidochalcone,
3,3′-diazidochalcone, 3,4′-diazidochalcone, 4,3′-diazidochalcone, 1,3-diphenyl-1,2,3-propanetrione-2- (O-acetyl) oxime 1,3-diphenyl-1,2,3-propanetrione-2- (On-propylcarbonyl) oxime, 1,3-diphenyl-1,2,3-propanetrione-2- (O-methoxycarbonyl ) Oximes,
1,3-diphenyl-1,2,3-propanetrione-
2- (O-ethoxycarbonyl) oxime, 1,3-diphenyl-1,2,3-propanetrione-2- (O-
Benzoyl) oxime, 1,3-diphenyl-1,2,2
3-propanetrione-2- (O-phenyloxycarbonyl) oxime, 1,3-bis (p-methylphenyl) -1,2,3-propanetrione-2- (O-benzoyl) oxime, 1,3- Bis (p-methoxyphenyl) -1,2,3-propanetrione-2- (O-ethoxycarbonyl) oxime, 1- (p-methoxyphenyl) -3- (p-nitrophenyl) -1,2,3 -Propanetrione-2- (O-phenyloxycarbonyl)
Oximes and the like can be used, but are not limited thereto.

The photopolymerization aid is preferably used in an amount of 0.1 to 50 parts by weight, more preferably 0.3 to 20 parts by weight, based on 100 parts by weight of the photosensitive polyimide contained in the present invention. If the amount is out of the range of 0.1 to 50 parts by weight, the intended sensitizing effect may not be obtained, or may adversely affect the developability. As the photopolymerization aid, one kind of compound may be used, or a plurality of kinds may be used in combination.

The photosensitive polyimide composition of the present invention may further contain a copolymer monomer in addition to the above-mentioned sensitizer and photopolymerization aid in order to further improve the exposure sensitivity. The copolymerized monomer is a compound having a carbon-carbon double bond and facilitates a photopolymerization reaction. Examples of the copolymerizable monomer include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, and tetramethylol. Propane tetraacrylate, tetraethylene glycol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, ethylene glycol dimethacrylate, pentaerythritol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexa Methacrylate, tetrame Roll propane tetra methacrylate,
Tetraethylene glycol dimethacrylate and the like are preferred, but not limited thereto.

The copolymerization monomer is preferably blended in an amount of 1 to 100 parts by weight, more preferably 3 to 50 parts by weight, based on 100 parts by weight of the photosensitive polyimide contained in the present invention. When deviating from the range of 1 to 100 parts by weight,
The desired effect may not be obtained or may adversely affect the developability. In addition, one kind of compound may be used as the copolymerization monomer, or a mixture of several kinds of compounds may be used.

The photosensitive polyimide composition of the present invention may contain a suitable organic solvent. If a suitable organic solvent is dissolved in the solution, it can be used in a solution (varnish) state, which is convenient when forming a film. The solvent used in this case is preferably an aprotic polar solvent from the viewpoint of solubility. Specifically, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N-benzyl-2
-Pyrrolidone, N, N-dimethylformamide, N, N
-Dimethylacetamide, dimethylsulfoxide, hexamethylphosphortriamide, N-acetyl-ε-caprolactam, dimethylimidazolidinone, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, γ-butyrolactone, and the like are preferable examples. These may be used alone or as a mixed system. Further, in order to improve coatability, a solvent such as toluene, xylene, diethyl ketone, methoxybenzene, or cyclopentanone may be mixed within a range that does not adversely affect the solubility of the polymer.

The resin pattern forming method of the present invention uses the photosensitive polyimide composition of the present invention to form a polyimide film made of a cured product of the composition by a photolithography technique.

In the resin pattern forming method of the present invention, first, a film made of the photosensitive polyimide composition of the present invention is formed on the surface of a supporting substrate. In the resin pattern forming method of the present invention, the surface of the support substrate may be previously treated with an adhesion aid in order to improve the adhesion between the film or the polyimide film after heat curing and the support substrate. Also,
An adhesion aid may be added to the varnish.

The coating made of the photosensitive polyimide composition is
For example, it is formed by forming a varnish film of the photosensitive polyimide composition and then drying it. The varnish film is formed by a means appropriately selected from means such as spin coating using a spinner, dipping, spray printing, screen printing, etc., according to the viscosity of the varnish. The thickness of the film can be adjusted by the application conditions, the solid content concentration of the present composition, and the like. Further, the film formed on the support in advance is peeled from the support to form a sheet made of the photosensitive polyimide composition, and the sheet is attached to the surface of the support substrate to form the film described above. May be.

Next, after irradiating the film with light (usually using ultraviolet light) through a photomask having a predetermined pattern, an unexposed portion is dissolved and removed with a basic aqueous solution.
Obtain the desired relief pattern. This developing step may be performed using a normal positive-type photoresist developing device.

In the resin pattern forming method of the present invention, a basic aqueous solution is used as a developer. The developer may be an aqueous solution of one compound or an aqueous solution of two or more compounds as long as the aqueous solution exhibits basicity. The basic aqueous solution is usually a solution in which a basic compound is dissolved in water. The concentration of the basic compound is usually 0.1 to 50% by weight / weight%.
It is preferably 30% by weight. Incidentally, the developer is to improve the solubility of the photosensitive polyimide precursor,
It further contains a water-soluble organic solvent such as methanol, ethanol, propanol, isopropyl alcohol, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide. You may.

Examples of the basic compound include hydroxides or carbonates of alkali metals, alkaline earth metals or ammonium ions, amine compounds and the like. Specifically, 2-dimethylaminoethanol, 3
-Dimethylamino-1-propanol, 4-dimethylamino-1-butanol, 5-dimethylamino-1-pentanol, 6-dimethylamino-1-hexanol, 2
-Dimethylamino-2-methyl-1-propanol, 3
-Dimethylamino-2,2-dimethyl-1-propano-
2-diethylaminoethanol, 3-diethylamino-1-propanol, 2-diisopropylaminoethanol, 2-di-n-butylaminoethanol, N, N
-Dibenzyl-2-aminoethanol, 2- (2-dimethylaminoethoxy) ethanol, 2- (2-diethylaminoethoxy) ethanol, 1-dimethylamino-2
-Propanol, 1-diethylamino-2-propano-
, N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N
-T-butyldiethanolamine, N-lauryldiethanolamine, 3-diethylamino-1,2-propanediol, triethanolamine, triisopropanolamine, N-methylethanolamine, N-ethylethanolamine, Nn-butylethanolamine, N
-T-butylethanolamine, diethanolamine,
Diisopropanolamine, 2-aminoethanol, 3
-Amino-1-propanol, 4-amino-1-butanol, 6-amino-1-hexanol, 1-amino-2
-Propanol, 2-amino-2,2-dimethyl-1-
Propanol, 1-aminobutanol, 2-amino-1
-Butanol, N- (2-aminoethyl) ethanolamine, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1,3-propanediol, 3-amino-1, 2-propanediol, 2-amino-2-hydroxymethyl-1,3-propanediol, sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate , Ammonium hydrogen carbonate, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, aminomethanol, 2-
Aminoethanol, 3-aminopropanol, 2-aminopropanol, methylamine, ethylamine, propylamine, isopropylamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, trimethylamine, triethylamine, tripropylamine, triisopropylamine It is preferable to use other compounds as long as they are soluble in water and the aqueous solution exhibits basicity.

The relief pattern formed by development is then washed with a rinsing liquid to remove the developing solvent. Preferable examples of the rinsing liquid include methanol, ethanol, isopropyl alcohol, and water having good miscibility with the developing liquid.

The relief pattern obtained by the above-mentioned treatment is heated at a temperature selected from the range of 160 ° C. to 250 ° C. and the solvent is dried to obtain a resin comprising the photosensitive polyimide composition of the present invention. The pattern is obtained with high resolution. This resin pattern has high heat resistance,
Excellent mechanical properties.

[0062]

[Embodiment 1] A. First Embodiment Synthesis of Photosensitive Polyimide 4.96 g of 4,4′-oxydiphthalic dianhydride (hereinafter abbreviated as ODPA) was placed in a 200 ml four-necked flask equipped with a moisture metering tube and a reflux condenser under a nitrogen stream. 0.
016 mol), 5.86 g of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane
(0.016 mol), pyridine 0.13 g (0.001
6 mol), 0.19 g (0.0016 mol) of benzoic acid and 38 g of N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) were added and stirred at 23 ° C. to form a clear solution in 1 hour.

Thereafter, the solution was heated and stirred at 180 ° C. for 3 hours. Water generated by the ring closure reaction was distilled off by azeotropy with toluene and collected in a water content tube, and the polyimide (compound 1a) was placed in the flask. Was obtained. Next, 0.03 g of t-butylcatechol and 2.48 g (0.016 mol) of isocyanateethyl methacrylate were added, and the mixture was stirred at 23 ° C. for 24 hours. The solution was poured into 1 liter of water, and the precipitated polymer was filtered. The sample was taken, washed twice with water, and dried under vacuum to obtain 13 g of a polymer.

[0064]

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The weight average molecular weight of this polymer measured by GPC (gel permeation chromatography) was 81,000 in terms of polystyrene. FIG. 1 shows a ¹ H-NMR (nuclear magnetic resonance) chart of the obtained compound. The measurement deuterated dimethyl sulfoxide (DMSO-d ₆₎ as the solvent were conducted tetramethylsilane (TMS) as the standard. In this chart, peaks derived from the residual solvent, water and the like are mixed.

B. Preparation of Photosensitive Polyimide Composition 10 g of the obtained polymer was added to 40.0 g of γ-butyrolactone.
In 4-diethylaminoethyl benzoate 20
After 0 mg was added and dissolved, the solution was filtered under pressure using a filter having a pore size of 5 μm to obtain a photosensitive polyimide composition in a solution state.

C. Evaluation of polyimide film The obtained solution was spin-coated on a silicon wafer with a spinner, and then dried on a hot plate at 90 ° C for 3 minutes to obtain a 10 µm thick coating film. After exposing this coating film to an intensity of 200 mJ / cm ² (ultraviolet light intensity of 365 nm) using a high-pressure mercury lamp of 500 W, 1% aqueous solution (developer) of 2.38% by weight of tetramethylammonium hydroxide at 20 ° C. After immersion for a minute, the film was developed, and then rinsed with water to obtain a polyimide film. This film was cured by heating at 200 ° C. for 60 minutes, and the solvent was evaporated to a thickness of 9.
A 2 μm film was obtained. From this result, it was found that the photosensitive material of this example reduced the film thickness only to 8% of the initial film thickness and showed a small volume shrinkage during curing.

The polyimide film was peeled from the silicon wafer, and the elongation characteristics of the film were measured. The elongation was as good as 8%. Further, the dependence of the film thickness after development on the amount of exposure was measured, and a sensitivity of 50 mJ / cm ² was obtained using the exposure amount at which the film thickness after development was half the thickness of the coated film.

D. Formation of Resin Pattern Further, using the photosensitive polyimide composition prepared in the step B, a coating film, exposure, development, and rinsing were performed in the same manner as in the formation of the polyimide film described above. However, at the time of exposure,
It was tightly covered with a photomask having a stripe pattern of 0 μm width. Thereby, consisting of a polyimide precursor,
A relief pattern having a sharp end face and a width of 10 μm was obtained. This pattern was subjected to a heat treatment in the same manner as in the formation of the above-mentioned polyimide film to obtain a high-resolution resin pattern made of polyimide.

Example 2 A. Synthesis of Photosensitive Polyimide In a 200 ml four-necked flask equipped with a moisture metering tube and a reflux condenser, 4.96 g (0.0
16 mol), 2.43 g of 3,5-diaminobenzoic acid
(0.016 mol), pyridine 0.13 g (0.001
6 mol), 0.19 g (0.0016 mol) of benzoic acid and 38 g of NMP were stirred at 23 ° C., and a clear solution was obtained in 1 hour.

Thereafter, this solution was heated and stirred at 180 ° C. for 3 hours. Water generated by the ring-closing reaction was distilled off by azeotropy with toluene and collected in a water content measuring tube to obtain a polyimide (compound 1b) solution. Was. Next, 0.03 g of t-butyl catechol and 1.24 g (0.008 mol) of isocyanate ethyl methacrylate were added, and the mixture was added at 23 ° C for 24 hours.
After stirring for 1 hour, the solution was poured into 1 liter of water, and the precipitated polymer was collected by filtration, washed twice with water, dried in vacuo, and 8.1.
g of polymer were obtained. The weight average molecular weight of this polymer is determined by GP
When measured by C (gel permeation chromatography), it was 76,000 in terms of polystyrene.

[0072]

Embedded image

B. Preparation of Photosensitive Polyimide Composition 10 g of the obtained polymer was added to 40.0 g of γ-butyrolactone.
And then added with 100 mg of mihira ketone and dissolved.
Pressure filtration was performed using a filter having a pore size of μm to obtain a photosensitive polyimide composition in a solution state.

C. Evaluation of polyimide film The obtained solution was spin-coated on a silicon wafer with a spinner, and then dried on a hot plate at 90 ° C for 3 minutes to obtain a coating film having a thickness of 10 µm. After exposing this coating film to an intensity of 200 mJ / cm ² (ultraviolet light intensity of 365 nm) using a high-pressure mercury lamp of 500 W, 2.38 at 20 ° C.
It was immersed in a 1% by weight aqueous solution of tetramethylammonium hydroxide (developer) for 1 minute to develop, and then rinsed with water to obtain a polyimide film. This film was heated at 200 ° C. for 60 minutes to evaporate the solvent to obtain a film having a thickness of 9.1 μm. From this result, it was found that the decrease in film thickness was only 9% of the initial film thickness, and that the volume shrinkage during curing was small.

The polyimide film was peeled from the silicon wafer, and the elongation characteristics of the film were measured. The elongation was as good as 8%. Further, the dependence of the film thickness after development on the amount of exposure was measured, and a sensitivity of 50 mJ / cm ² was obtained using the exposure amount at which the film thickness after development was half the thickness of the coated film.

D. Formation of Resin Pattern Further, using the photosensitive polyimide composition prepared in the step B, a coating film, exposure, development, and rinsing were performed in the same manner as in the formation of the polyimide film described above. However, at the time of exposure,
It was tightly covered with a photomask having a stripe pattern of 0 μm width. Thereby, consisting of a polyimide precursor,
1 with sharp edge without peeling on silicon wafer
A relief pattern having a width of 0 μm was obtained. This pattern was subjected to a heat treatment in the same manner as in the formation of the above-mentioned polyimide film to obtain a high-resolution resin pattern made of polyimide.

<Examples 3 to 12> The acid dianhydride, diamine, and isocyanate compounds shown in Tables 1 and 2 were reacted under the same reaction conditions as in Example 1 to synthesize a photosensitive polyimide. The weight average molecular weight of the obtained photosensitive polyimide was 20,000 to 200,000.

[0078]

[Table 1]

[0079]

[Table 2]

The obtained photosensitive polyimide was dissolved in a solvent in the same manner as in Example 1, and a sensitizer, a photopolymerization aid and a copolymerized monomer were added to prepare a photosensitive polyimide composition. Tables 3 and 4 show the results obtained by forming a film in the same manner as in Example 1 and examining the sensitivity, volume shrinkage during curing, development time, and film elongation. In Tables 3 and 4, the amount of each additive per 100 parts by weight of the photosensitive polyimide precursor is shown in parentheses.

[0081]

[Table 3]

[0082]

[Table 4]

The conditions for film formation and evaluation were the same as in Example 1, and the film thickness was 10 to 20 μm. The sensitivity is 50 mJ / cm, as the exposure amount at which the film thickness after development becomes half of the coating film thickness.
^{A value of 2} or less was regarded as favorable, and the volume shrinkage during curing was regarded as favorable when the decrease in film thickness relative to the initial film thickness was within 10%. The developing time was determined to be good if the developing time was 3 minutes or less using a developing solution composed of a 2.38% by weight aqueous solution of tetramethylammonium hydroxide. Further, the elongation of the final polyimide film was determined to be 8% or more.

Comparative Example A photosensitive polyimide precursor was synthesized in the same manner as in Example 1 of JP-A-8-155324, and this precursor was used to produce a photosensitive polyimide in the same manner as in Example 1 of the present application. A precursor composition was prepared and a 10 μm coating was formed. Subsequently, after exposing at the same exposure amount as in Example 1 through a photomask, developing, heating and curing at 350 ° C. for 60 minutes, a thickness of 5.4 μm made of photosensitive polyimide
m was obtained. From this result, the decrease in the film thickness was 4% of the initial film thickness.
It reached 6%, and the volume shrinkage upon curing was large.

[0085]

As described in detail above, the photosensitive polyimide composition of the present invention is soluble in a basic aqueous solution, and can be developed using an aqueous basic aqueous solution instead of an organic solvent. Can be. Therefore, if a resin pattern is formed using the photosensitive polyimide composition of the present invention, the swelling of the exposed portion during development, an adverse effect on the health of workers, the trouble of waste liquid treatment, etc. Problem can be avoided. Further, the photosensitive polyimide of the present invention,
Since it has a ring-closed imide structure, curing shrinkage due to heat is small and pattern dimensional stability is high. Therefore, it can be used as a protective film such as a surface coat film of a semiconductor element and an interlayer insulating film of a thin-film multilayer wiring board.

[Brief description of the drawings]

FIG. 1 shows ¹ H of photosensitive polyimide synthesized in Example 1.
-It is an NMR chart.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/028 G03F 7/028 7/075 511 7/075 511 7/32 7/32 H01L 21/027 H01L 21/30 502R (72) Inventor Fumio Kataoka 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi, Ltd.Production Technology Laboratory (72) Inventor Makoto Kaji 4-3-1-1, Higashicho, Hitachi, Ibaraki Hitachi (72) Inventor Minoru Sugiura 4-3-1-1, Higashimachi, Hitachi, Ibaraki Prefecture Hitachi Chemical Co., Ltd.Ibaraki Research Laboratory F-term (reference) 2H025 AA00 AA01 AA04 AA10 AA20 AB20 AC01 AD01 BC13 BC69 BC78 BC83 BC92 CA00 CC20 FA17 2H096 AA27 BA06 EA02 GA08 4J027 AD04 BA19 BA20 BA23 BA25 BA26 BA28 CB10 CC05 CD06 CD10 4J043 PA02 PA04 PA05 PA08 PC016 PC066 PC086 PC 166 PC206 QB15 QB26 QB31 RA35 SA06 SA62 SA71 SB01 SB03 TA14 TA22 TB01 TB03 UA022 UA121 UA122 UA132 UA142 UA152 UA261 UA262 UB011 UB012 UB021 UB022 UB061 VA062 VA1UB1 UB301 UB301 UB301 UB301 UB301 B1

Claims (14)

[Claims] 1. A photosensitive polyimide obtained by reacting a first polyimide having a first repeating unit represented by the following general formula (Formula 1) with an isocyanate compound having a carbon-carbon double bond. Embedded image (Wherein, R ¹ is a tetravalent organic group containing 4 or more carbons, R ² is a trivalent or tetravalent organic group containing an aromatic ring,
A ¹ is a carboxyl group or a phenolic hydroxyl group, and n is 1 or 2. ) 2. The first polyimide further has a second repeating unit represented by the following general formula (Chemical Formula 2). (Wherein, R ³ is a tetravalent organic group containing 4 or more carbon atoms, and R ⁴ is an aromatic ring or a divalent organic group containing silicon.) , The sum of the number of the first repeating units and the number of the second repeating units is 100
And the number of the first repeating units is 10 to 10
0. The photosensitive polyimide according to claim 1, wherein the number of the second repeating unit is 0 to 90. 3. The photosensitive polyimide according to claim 1, wherein the isocyanate compound is a compound represented by the following general formula (Formula 3). Embedded image (Wherein, R ⁵ , R ⁶ and R ⁷ are each independently selected from hydrogen, an alkyl group, a phenyl group, a vinyl group and a propenyl group, and R ⁸ represents a divalent organic group. ) 4. A photosensitive polyimide having a third repeating unit represented by the following general formula (Formula 4). Embedded image (R ¹ is a tetravalent organic group containing four or more carbons, R ² is a trivalent or tetravalent organic group containing an aromatic ring, R ¹⁰ is a photosensitive group, n
Is 1 or 2. ) 5. The method according to claim 1, further comprising a third repeating unit represented by the following general formula (Formula 2). (Wherein, R ³ is a tetravalent organic group containing 4 or more carbons, and R ⁴ is an aromatic ring or a divalent organic group containing silicon.) When the sum of the number of repeating units and the number of second repeating units is 100, the first
4. The photosensitive polyimide according to claim 3, wherein the number of repeating units is 10 to 100, and the number of the second repeating units is 0 to 90. 6. The photosensitive polyimide according to claim 4, wherein said R ¹⁰ is represented by the following general formula (Formula 5). Embedded image (Wherein, R ⁵ , R ⁶ and R ⁷ are hydrogen, carbon 1
And R ⁵ is a divalent organic group, which is independently selected from an alkyl group having 5 to 5 carbon atoms, an aromatic group having 5 to 30 carbon atoms, and an alkenyl group having 1 to 5 carbon atoms. ) 7. A method according to claim 1, wherein each of R ¹ and R ³ is at least one of organic groups represented by any of the structural formulas shown in the following structural formula group (Formula 6). The photosensitive polyimide according to claim 1 or 4, wherein Embedded image 8. The above R ² is an organic group represented by any of the structural formulas shown in the following structural formula group (Formula 7):
2. The method as claimed in claim 1, wherein at least one of them is selected.
Or the photosensitive polyimide according to 4. Embedded image 9. The method according to claim 2, wherein R ⁴ is
The organic group represented by any one of the structural formulas represented by the following structural formula groups (Chemical Formula 8), (Chemical Formula 9) and (Chemical Formula 10). Or the photosensitive polyimide according to 5. Embedded image Embedded image Embedded image 10. The photosensitive polyimide according to claim 1, wherein the weight average molecular weight is 10,000 to 200,000. 11. A process for obtaining a photosensitive polyimide by reacting a polyimide having a repeating unit represented by the following general formula (Formula 1) with an isocyanate compound having a carbon-carbon double bond. A method for producing a photosensitive polyimide. Embedded image (Wherein, R ¹ is a tetravalent organic group containing 4 or more carbons, R ² is a trivalent or tetravalent organic group containing an aromatic ring,
A ¹ is a carboxyl group or a phenolic hydroxyl group, and n is 1 or 2. ) 12. The photosensitive polyimide according to claim 1, comprising 100 parts by weight, a sensitizer of 0.1 to 50 parts by weight, and a photopolymerization aid of 0.1 to 50 parts by weight. A photosensitive polyimide composition, comprising: 13. A method comprising the steps of: irradiating a film made of the photosensitive polyimide composition according to claim 12 with light through a mask having a predetermined pattern, and then developing the film using a basic aqueous solution. A method for forming a characteristic resin pattern. 14. A negative photosensitive material for forming a protective film or an insulating film, comprising the photosensitive polyimide according to claim 1.