JPH07219224A - Heat resisatant photosensitive polymer composition and production of relief pattern - Google Patents

Abstract

PURPOSE:To obtain a photosensitive polymer compsn. giving a satisfactory pattern shape even in the case of a thick film. CONSTITUTION:This photosensitive polymer compsn. contains a polymer (a) represented by the formula (where R1 is >=2C tetravalent org. group, R2 is >=2C divalent org. group and each carboxyl group bonds at the o-position to each C atom to which an amido bond has been bonded), a compd. (b) contg. one or more unsatd. bonds capable of dimerization or polymn. under chemical rays and one amino group or its quaternized salt and 4,4'-diazido-3,3'- dimethoxybiphenyl (c). This compsn. is applied on a substrate, dried, exposed and developed to produce the objective relief pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant photosensitive polymer composition, and more specifically, a polyimide-based heat-resistant composition which can be applied as a surface protective film or an interlayer insulating film for electronic parts such as semiconductor elements by heat treatment. The present invention relates to a heat-resistant photosensitive polymer composition which becomes a polymer and a method for producing a relief pattern using this composition.

[0002]

2. Description of the Related Art Polyimide has excellent heat resistance and mechanical properties,
Further, it is widely used as a surface protective film and an interlayer insulating film of a semiconductor element because of its advantages such as easy film formation and flattened surface. When polyimide is used as the surface protective film and the interlayer insulating film, the step of forming through holes and the like is performed by an etching process using a photoresist. However, there is a problem in that the process includes coating and peeling of the photoresist and is complicated. Therefore, heat-resistant materials having photosensitivity have been studied for the purpose of streamlining the work process.

With regard to the photosensitive polyimide composition, carbonic acid which is dimerizable or polymerisable with polyamic acid by actinic radiation is used.
A composition containing a compound having a carbon double bond and an amino group and an aromatic bisazide compound (Japanese Patent Publication No. 3-36861).
No. publication) is known. When the photosensitive polyimide composition is used, it is usually applied on a substrate in a solution state, dried, irradiated with an actinic ray through a mask, and the unexposed portion is removed with a developing solution to form a pattern. However, the above-mentioned photosensitive polyimide composition has a problem that the light absorption of the aromatic bisazide with respect to the exposure wavelength is large and the pattern shape is deteriorated when a thick film is formed.

[0004]

DISCLOSURE OF THE INVENTION The present invention overcomes the above-mentioned problems of the prior art, and provides a heat-resistant photosensitive polymer composition having a good pattern shape which can be obtained even in a thick film, and a relief pattern using the composition. It provides a manufacturing method.

[0005]

The present invention comprises (a) general formula (I)

[Chemical 2] (In the formula, R ₁ represents a tetravalent organic group having 2 or more carbon atoms,
R ₂ represents a divalent organic group having 2 or more carbon atoms, and each carboxyl group is bonded to an ortho position with respect to each carbon atom to which an amide bond is bonded. )
A compound containing one or more unsaturated bonds dimerizable or polymerizable by actinic radiation and one amino group or a quaternized salt thereof, and (c) 4,4′-diazide-3,3 ′
The present invention relates to a heat-resistant photosensitive polymer composition containing dimethoxybiphenyl and a method for producing a relief pattern using this composition. The heat-resistant photosensitive polymer composition may contain a sensitizer for the component (c).

In the present invention, the component (a) is, for example,
It is obtained by reacting diamine and tetracarboxylic dianhydride in a solvent. Here, as the tetracarboxylic dianhydride, for example, pyromellitic dianhydride, 3,3 ′,
4,4'-biphenyltetracarboxylic dianhydride, 3,
3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride, 3,3', 4,4'-biphenyl ether tetracarboxylic acid dianhydride, cyclopentane tetracarboxylic acid dianhydride, 1,2,5 6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,5,6- Pyridine tetracarboxylic dianhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, 4,4'-sulfonyldiphthalic dianhydride, 3,3 ', 4,4'-tetraphenylsilane Known acid anhydrides such as tetracarboxylic dianhydride and 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride may be used alone or in combination of two or more.

As the diamine, for example, 4,
4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide,
Aromatic diamine compounds such as benzidine, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine and 2,6-naphthalenediamine, the following general formula (II)

[Chemical 3] (Wherein R ₃ represents an alkylene group, R ₄ represents an alkyl group, and q represents an integer of 1 or more), for example,

[Chemical 4] Compounds such as can also be used. The diamine has the general formula (III)

[Chemical 5] (In the formula, Ar means an aromatic group, and Y is SO ₂ or C.
A diaminoamide compound represented by the formula (1), which means O, and one amino group and Y—NH ₂ are located in the ortho positions with respect to each other.
For example, 4,4'-diaminodiphenyl ether-3-
Compounds such as sulfonamide, 3,4'-diaminodiphenyl ether-4-sulfonamide, 3,4'-diaminodiphenyl ether-3'-sulfonamide, 3,3'-diaminodiphenyl ether-4-sulfonamide can also be used. . These diamines can be used alone or in combination of two or more.

For the reaction of diamine and tetracarboxylic dianhydride, for example, N-methyl-2-pyrrolidone, N, N
-Inert solvents such as dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, tetramethylene sulfone and p-chlorophenol are used.

When the polymer as the component (a) is produced,
Preferably the diamine is first dissolved in the above inert solvent and then tetracarboxylic dianhydride is added, preferably about 8
Stirring is performed while maintaining a temperature of 0 ° C. or lower, more preferably around room temperature or lower than room temperature. The preferable ratio (molar ratio) of diamine and tetracarboxylic dianhydride is 0.8 / 1 to 1 /
The range is 0.8, and a more preferable ratio is 0.9 / 1 to
The range is 1 / 0.9. The reaction time is 3 to 24 hours,
A preferable weight average molecular weight is 20,000 or more.
The reaction proceeds promptly, and the viscosity of the reaction system gradually rises to form a polymer.

Examples of the component (b) compound used in the present invention include compounds represented by the general formula (IV)

[Chemical 6] (In the formula, R ₅ and R ₆ represent an alkyl group having 1 to 5 carbon atoms, R ₇ represents an alkylene group having 2 to 6 carbon atoms, and R ₈ represents a hydrogen atom or 1 to 5 carbon atoms. 6 means an alkyl group, and X means —O— or —NH—). In particular,

[Chemical 7] And so on. The component (b) is preferably added to the carboxyl group of the polymer as the component (a) from the viewpoint of the difference in dissolution rate between the exposed portion and the unexposed portion and the allowable width of the developing conditions.
The amount is 2 to 3 equivalents, more preferably 0.5 to 2 equivalents.

The component (c) used in the present invention is 4,
It is 4'-diazide-3,3'-methoxybiphenyl. Examples of the component (c) include 4,4'-diazide-3,
An aromatic bisazide compound other than 3'-methoxybiphenyl may be used in combination. As the aromatic bisazide compound used in combination, 4,4′-diazidophenyl ether,
4,4'-diazidophenyl sulfone, 3,3'-diazidophenyl sulfone, 4,4'-diazidodiphenyl disulfide, 4,4'-diazidodiphenyl sulfide, 4,4'-diazidostilbene, 4 , 4'-diazidochalcone, 2,6-diazidobenzal cyclohexanone, 2,6-diazidobenzal-4-methylcyclohexanone, 2,6-diazidobenzal-4-hydroxycyclohexanone, 2,6-diazidobenzal-4-
Examples include carboxycyclohexanone. The component (c) is 0.5 with respect to 100 parts by weight of the polymer as the component (a), in view of the difference in dissolution rate between the exposed portion and the unexposed portion and the physical properties of the film.
To 20 parts by weight, more preferably 1 to 10 parts by weight.

As the sensitizer for the component (c) which can be used in the present invention, 3- (2'-benzimidazolyl)-
Coumarins such as 7-diethylaminocoumarin, 3- (2'-benzthiazolyl) -7-diethylaminocoumarin, 7-diethylamino-3-cenoylcoumarin, 3,3-carbonylbis (7-diethylaminocoumarin), Michler's ketone, benzanthrone , 2,6-di (4'-
Diethylaminobenzal) -N-methylazacyclohexanone and the like. The component (d) is 0.01 to 2 parts by weight based on 100 parts by weight of the polymer as the component (a), in view of the difference in dissolution rate between the exposed portion and the unexposed portion and the pattern shape.
It is more preferably blended in the range of 0.05 to 1 part by weight.

The photosensitive polymer composition of the present invention comprises a component (a), a component (b), a component (c), and optionally a sensitizer for the component (c) dissolved in a suitable organic solvent. By doing so, it can be obtained in a solution state. Examples of the organic solvent used at this time include N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, tetramethylenesulfone, N-acetyl-. An inert solvent such as ε-caprolactam is used.

From the heat-resistant photosensitive polymer composition of the present invention, a relief pattern of a polyimide compound can be obtained as follows. That is, a glass substrate, a semiconductor, a metal oxide insulator (for example, TiO ₂ , SiO _2, etc.),
The heat-resistant photosensitive polymer composition containing the insoluble solvent is spin-coated on a supporting substrate such as silicon nitride using a spinner or the like, and then dried using a hot plate, an oven, or the like. Then, the photosensitive polymer composition that has formed a film on the supporting substrate is irradiated with an actinic ray such as ultraviolet rays, visible rays, and radiation through a mask. A relief pattern is obtained by removing the unexposed portion with a developing solution. Examples of the developer include N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide,
Dimethyl sulfoxide, hexamethylphosphoramide,
Tetramethylene sulfone, N-acetyl-ε-caprolactam and the like can be used alone or as a mixed solution with water, methanol, ethanol, isopropanol, toluene, xylene and the like. Then, the relief pattern thus obtained is subjected to a heat treatment at 150 to 450 ° C. to form a relief pattern of a heat resistant polymer having an imide ring or other cyclic group.

[0015]

EXAMPLES The present invention will be described below with reference to examples. Example 1 376.3 g of N-methyl-2-pyrrolidone was charged into a 0.5-liter flask equipped with a stirrer, a thermometer, a nitrogen introduction tube, and a Dimroth condenser, and 4,4'-diaminodiphenyl ether 40. 05 g was added and dissolved by stirring.
Next, 21.81 g of pyromellitic dianhydride and 32.22 g of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride were added to this solution, and the mixture was allowed to stand at 25 ° C. for 6 hours and then 7
The mixture was stirred and reacted at 0 ° C. for 8 hours. The obtained polyamic acid solution had a nonvolatile concentration of 20% by weight and a viscosity of 80 poise. To 100.0 g of this solution, 13.37 g of 2-dimethylaminoethyl methacrylate, 0.75 g of 4,4'-diazide-3,3'-dimethoxybiphenyl and 0.08 g of 3,3-carbonylbis (7-diethylaminocoumarin) were added. Then, the mixture was stirred and dissolved. 3μ of this solution
A photosensitive polymer composition was obtained by pressure filtration using an m-pore Teflon filter. The obtained photosensitive polymer composition was spin-coated on a silicon wafer using a spinner and dried by heating on a hot plate at 100 ° C. for 5 minutes.
A coating film of μm was obtained. 3 through a photomask on this coating
Contact exposure was carried out from a distance of 0 cm for 75 seconds using a high-pressure mercury lamp of 1 kW. Then N-methyl-2-pyrrolidone 70
2 parts by weight of a developing solution consisting of 30 parts by weight of methanol and
Paddle development was carried out for 80 seconds, followed by washing with ethanol to obtain a relief pattern. The obtained relief pattern was placed under a nitrogen atmosphere at 140 ° C. for 30 minutes, and at 200 ° C. for 30 minutes.
Heat treatment was performed at 0 ° C. for 1 hour to obtain a relief pattern of the polyimide film.

Example 2 395.6 g of N-methyl-2-pyrrolidone was placed in a 0.5 liter flask equipped with a stirrer, a thermometer, a nitrogen inlet tube, and a Dimroth condenser tube, and 4,4'-diamino was added. Diphenyl ether (40.05 g) was added and dissolved with stirring.
Next, 58.84 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added to this solution, and the mixture was reacted at 25 ° C. for 8 hours and then at 70 ° C. for 7 hours for reaction. The obtained polyamic acid solution had a nonvolatile concentration of 20% by weight and a viscosity of 75 poise. To this solution 100.0 g, 2-dimethylaminoethyl methacrylate 12.72 g, 4,
4'-diazide-3,3'-dimethoxybiphenyl 0.
70 g and benzanthrone 0.20 g were added and dissolved with stirring. This solution was pressure-filtered using a Teflon filter having 3 μm pores to obtain a photosensitive polymer composition. The resulting photopolymer composition was spin coated on a silicon wafer using a spinner and heated on a hot plate at 100 ° C. for 5 hours.
It was heated and dried for a minute to obtain a coating film of 20 μm. This coating film was contact-exposed through a photomask from a distance of 30 cm for 80 seconds using a high-pressure mercury lamp of 1 kW. Then 70 parts by weight of N-methyl-2-pyrrolidone and 30 parts of methanol
Perform paddle development for 240 seconds with a developer composed of parts by weight,
It was washed with ethanol to obtain a relief pattern. The obtained relief pattern is heated at 140 ° C. under a nitrogen atmosphere for 30 minutes.
Min, heat treatment at 200 ℃ for 30 minutes, 350 ℃ for 1 hour,
A relief pattern of the polyimide film was obtained.

Comparative Example 1 In 100.0 g of the solution of the polyamic acid obtained in Example 1, 13.37 g of 2-dimethylaminoethyl acrylate and 0.94 g of 2,6-di (4'-azidobenzal) -4-carboxycyclohexanone Was added and dissolved by stirring. This solution was pressure-filtered using a Teflon filter having 3 μm pores to obtain a photosensitive polymer composition. The obtained photosensitive polymer composition was spin-coated on a silicon wafer using a spinner, and dried by heating on a hot plate at 100 ° C. for 5 minutes to obtain a coating film of 20 μm. The coating film was contact-exposed through a photomask from a distance of 30 cm for 75 seconds using a high-pressure mercury lamp of 1 kW. Next, paddle development was performed for 280 seconds with a developer consisting of 70 parts by weight of N-methyl-2-pyrrolidone and 30 parts by weight of methanol, and washed with ethanol to obtain a relief pattern. The obtained relief pattern is placed in a nitrogen atmosphere at 140 ° C. for 30 minutes and at 200 ° C. for 3 minutes.
Heat treatment was performed for 0 minutes at 350 ° C. for 1 hour to obtain a relief pattern of the polyimide film. The results of observing the cross-sectional shapes of the relief patterns obtained in Examples 1 and 2 and Comparative Example 1 by SEM are shown in FIGS. 1, 2 and 3, respectively. In the figure, 1 is a relief pattern and 2 is a silicon wafer. The relief pattern of the example has an excellent shape as compared with the comparative example.

[0018]

EFFECTS OF THE INVENTION The photosensitive polymer composition of the present invention has a good pattern even in a thick film, and can be used as a surface protective film for semiconductor elements, an interlayer insulating film and the like.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a result of observing a cross-sectional shape of a relief pattern obtained in Example 1 with an SEM.

FIG. 2 is a schematic diagram of a result of observing a cross-sectional shape of the relief pattern obtained in Example 2 with an SEM.

FIG. 3 is a schematic diagram of a result of observing a cross-sectional shape of the relief pattern obtained in Comparative Example 1 with an SEM.

[Explanation of symbols]

 1 relief pattern 2 silicon wafer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sato Court 4-13-1, Higashimachi, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Yamazaki Factory

Claims (3)

[Claims] 1. (a) General formula (I): (In the formula, R ₁ represents a tetravalent organic group having 2 or more carbon atoms,
R ₂ represents a divalent organic group having 2 or more carbon atoms, and each carboxyl group is bonded to an ortho position with respect to each carbon atom to which an amide bond is bonded. ) A compound containing one or more unsaturated bonds dimerizable or polymerizable by actinic radiation and one amino group or a quaternized salt thereof, and (c) 4,4'-diazide-3,3'-dimethoxy. A heat-resistant photosensitive polymer composition containing biphenyl. 2. A heat-resistant photosensitive polymer composition which further comprises a sensitizer for the component (c). 3. A method for producing a relief pattern, which comprises coating the heat-resistant photosensitive polymer composition according to claim 1 on a supporting substrate, drying, exposing and developing.