JP2000219740A - Polyimide precursor, photosensitive resin composition, production of relief pattern, and electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyimide precursor which is excellent in i-ray transmission and gives a polyimide resin with low thermal expansion by selecting a polyimide precursor having thermally decomposable separable groups. SOLUTION: This precursor has repeating units represented by formula I (wherein Ar1 to Ar4 are each an aromatic group provided at least one of them has a thermally decomposable separable group; X and Y are each a single bond or a divalent group; and R1 and R2 are each OH or a monovalent organic group). Preferably, the thermally decomposable separable group is carboxy, an acyloxy, alkoxycarbonylamino, alkylaminocarbonyloxy or alkylazo. Preferably, X and Y are each a single bond or p-phenylene. Preferably, the monovalent organic group in the case of R1 or R2 is a photosensitive group having a carbon- carbon double bond. The polyimide precursor of formula I is obtained by reacting a tetracarboxylic acid (derivative) of formula II with a diamine of formula III, if necessary in an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyimide precursor, a photosensitive resin composition, a method for producing a relief pattern using the composition, and an electronic component. More specifically, using a polyimide precursor having high i-line transmittance, a polyimide precursor which can be converted into a polyimide heat-resistant polymer to be used as a surface protective film, an interlayer insulating film and the like of an electronic component such as a semiconductor device by heat treatment. The present invention relates to a body, a photosensitive resin composition, a method for producing a relief pattern using the composition, and an electronic component.

[0002]

2. Description of the Related Art In recent years, in the semiconductor industry, an organic material having excellent heat resistance, such as a polyimide resin, has been used as an interlayer insulating material, which has conventionally been formed using an inorganic material, taking advantage of its characteristics. Have been. However, formation of a circuit pattern on a semiconductor integrated circuit or a printed circuit board is complicated and diversified, such as forming a resist material on the base material surface, removing unnecessary portions by exposing and etching predetermined portions, and cleaning the substrate surface. Since a pattern is formed through a series of steps, there is a demand for development of a heat-resistant photosensitive material that can use a necessary portion of a resist as an insulating material as it is even after pattern formation by exposure and development.

As these materials, for example, heat-resistant photosensitive materials using photosensitive polyimide, cyclized polybutadiene or the like as a base polymer have been proposed. Particularly, photosensitive polyimide has excellent heat resistance and elimination of impurities. Has attracted particular attention because of its ease of use. As such a photosensitive polyimide, a system comprising a polyimide precursor and a dichromate (Japanese Patent Publication No. 49-17374) was first proposed, but this material has practical photosensitivity. In addition, it has advantages such as high film-forming ability, but has disadvantages such as lack of storage stability and chromium ions remaining in polyimide, and thus has not been put to practical use.

[0004] In order to avoid such a problem, for example, a method of mixing a compound having a photosensitive group with a polyimide precursor (Japanese Patent Application Laid-Open No. 54-109828) discloses a method in which a functional group and a photosensitive group in the polyimide precursor are mixed. A method of reacting with a functional group of a compound having a compound to give a photosensitive group (JP-A-56-2
No. 4343, Japanese Unexamined Patent Publication No. 60-100143)
And so on. However, these photosensitive polyimide precursors use an aromatic monomer having excellent heat resistance and mechanical properties as a basic skeleton, and due to the absorption of the polyimide precursor itself, the light transmittance in the ultraviolet region is low, and However, the photochemical reaction in the portion cannot be performed sufficiently effectively, resulting in a problem that the sensitivity is low and the shape of the pattern is deteriorated. In recent years, with the increasing integration of semiconductors, processing rules have become increasingly smaller, and higher resolutions have been required.

For this reason, a conventional contact / proximity exposure apparatus using parallel rays has been replaced by a 1: 1 projection exposure apparatus called a mirror projection and a reduction projection exposure apparatus called a stepper. The stepper utilizes a monochromatic light such as an excimer laser and a high-power oscillation line of an ultra-high pressure mercury lamp. Until now, g-line steppers using visible light (wavelength: 435 nm) called g-line of an ultra-high pressure mercury lamp have been the mainstream stepper. However, in order to respond to the demand for finer processing rules, a stepper to be used is used. Needs to be shortened. Therefore, the exposure equipment used is from a g-line stepper (wavelength: 435 nm) to an i-line stepper (wavelength: 3).
65 nm).

However, conventional photosensitive polyimide base polymers designed for contact / proximity exposure machines, mirror projection projection exposure machines, and g-line steppers have low transparency due to the above-mentioned reasons, especially i-line. (Wavelength: 365 nm) because there is almost no transmittance.
A decent pattern cannot be obtained with an i-line stepper. In addition, a polyimide film for surface protection is required to be a thicker film corresponding to LOC (lead-on-chip), which is a high-density mounting method of a semiconductor element. The problem gets worse. Therefore, there is a strong demand for a photosensitive polyimide having a high i-line transmittance and a polyimide pattern having a good pattern shape by an i-line stepper. To increase the i-line transmittance,
It has been reported that the introduction of a substituent on the aromatic ring of the main chain is effective (Japanese Patent Application Laid-Open No. 8-337652).

The diameter of a silicon wafer serving as a substrate is
It has been increasing year by year, and there has been a problem that the warpage of the silicon wafer on which the polyimide as the surface protective film is formed becomes larger than before due to the difference in thermal expansion coefficient between the polyimide and the silicon wafer. Therefore, there is a strong demand for a photosensitive polyimide having a lower thermal expansion property than conventional polyimides. In general, low thermal expansion can be achieved by making the molecular structure rigid. However, in the case of the rigid structure, almost no i-line is transmitted, so that the photosensitive characteristics deteriorate.

[0008]

SUMMARY OF THE INVENTION The present invention provides a polyimide precursor which has good i-line transmittance by itself and can provide a low thermal expansion polyimide resin after imidization. The present invention also provides a photosensitive resin composition which itself has good i-line transmittance and gives a low thermal expansion polyimide resin after imidization.

Further, the present invention provides, in addition to the above-mentioned problems, a photosensitive resin composition having high sensitivity to i-line. Another object of the present invention is to provide a photosensitive resin composition which gives a more favorable pattern shape in addition to the above-mentioned problems.

Further, the present invention uses a polyimide resin having a low thermal expansion property after imidization while having a good i-line transmittance as a polyimide precursor, thereby providing a good pattern shape and an extremely small residual stress. It is intended to provide a method for producing a pattern capable of forming a pattern. Another object of the present invention is to provide an electronic component having extremely low residual stress after forming a polyimide resin film and having excellent reliability.

[0011]

According to the present invention, there is provided a compound represented by the general formula (1):

Embedded image (Wherein, Ar ¹ , Ar ² , Ar ³ and Ar ⁴ are each independently an organic group having an aromatic ring, X and Y are each independently a single bond or a divalent group, R ¹ and R ² is independently OH or a monovalent organic group, and Ar ¹ , Ar ² , Ar
^At least one of Ar ³ and Ar ⁴ has a thermally decomposable leaving group).

[0012] The present invention also relates to a polyimide precursor, wherein the thermally decomposable leaving group is a carboxyl group, an acyloxy group, an alkoxycarbonylamino group, an alkylaminocarbonyloxy group or an alkylazo group. The present invention also relates to a polyimide precursor wherein X and Y are a single bond or a p-phenylene group.

[0013] The present invention, ^{R 1} in the general formula (1)
And a polyimide precursor in which the monovalent organic group in R ² is a photosensitive group having a carbon-carbon unsaturated double bond.
The present invention also relates to a photosensitive resin composition containing the polyimide precursor. Further, the present invention provides a photosensitive group having a carbon-carbon unsaturated double bond in which the monovalent organic group in R ¹ and R ² in the general formula (1) is bonded to a carboxyl group via a salt complex. Which is a photosensitive resin composition.

Further, the present invention provides a method for preparing the above R ¹ and R ² using a derivative of acrylic acid or methacrylic acid having an amino group.
And a photosensitive resin composition provided with a monovalent organic group. The present invention also provides a step of applying the photosensitive resin composition on a supporting substrate and drying, exposing, developing, and thermally desorbing a thermally decomposable leaving group of a polyimide precursor to form a polyimide. The present invention relates to a method for producing a relief pattern including a step of performing The present invention also relates to a method for producing a relief pattern, wherein the exposing step is performed using i-line as an exposure light source. Furthermore, the present invention relates to an electronic component having a layer of a pattern obtained by the above-mentioned manufacturing method.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyimide precursor of the present invention has a repeating unit represented by the above general formula (1). Ar ¹ , Ar ² , Ar ³ and Ar in the above general formula (1)
⁴ is an organic group (hereinafter, referred to as an aromatic group) having an aromatic ring (benzene ring, naphthalene ring, etc.) each independently.

As Ar ¹ and Ar ² ,

Embedded image Is preferred,

Embedded image (Wherein X is defined in the same manner as X in the general formula (1), and Z is a thermally decomposable leaving group).

Further, among Ar ³ and Ar ⁴ ,

Embedded image Is preferred,

Embedded image Is more preferable,

Embedded image (Wherein Y is defined in the same manner as Y in the general formula (1), and Z is a thermally decomposable leaving group).

Ar ¹ , Ar ² , Ar ^3, and Ar ⁴ may have a substituent on the aromatic ring, and such a substituent may have a branched carbon number of 1 to 1. 10 alkyl groups, alkenyl groups having 1 to 10 carbon atoms, alkynyl groups having 1 to 10 carbon atoms, phenyl groups, aralkyl groups having 1 to 10 carbon atoms, cyano groups, acyl groups, carboxyl groups, carbon atoms An alkoxycarbonyl group having 1 to 10, a halogen atom, a hydroxy group, an alkoxy group having 1 to 10 carbon atoms, an acyloxy group, an amino group, an alkylamino group having 1 to 10 carbon atoms, an azide group, a mercapto group, an alkylthio group, 1 to 1 carbon atoms
0 alkylsulfonyl group, 1 carbon atom of the alkyl group
And 10 to 10 trialkylsilyl groups.

In addition, Ar ¹ and A are represented by divalent substituents.
r ² or a ring may be formed between Ar ³ and Ar ⁴ . Examples of the divalent substituent include an optionally branched alkylene group having 1 to 5 carbon atoms, a carbonyl group, an oxygen atom, an imino group, a sulfur atom, a sulfonyl group, and a dialkylsilylene group. In the general formula (1), X and Y each independently represent a single bond or a divalent group, and examples of the divalent group include an oxygen atom, a carbonyl group, a sulfonyl group, a p-phenylene group, a m-phenylene group, A dimethylmethylene group and a bis (trifluoromethyl) methylene group are preferable, and among them, a single bond and a p-phenylene group are more preferable.

The thermally decomposable leaving group includes a carboxyl group, an acyloxy group, an alkoxycarbonylamino group,
Examples thereof include an alkylaminocarbonyloxy group and an alkylazo group, which may be directly bonded to an aromatic ring or bonded to a substituent on the aromatic ring. The number of the heat-decomposable leaving groups may be one or more in the repeating unit of the general formula (1), and preferably one or two.

The polyimide precursor of the present invention has the general formula (2)

Embedded image (Wherein, Ar ¹ , Ar ² and X are the same as above, provided that X contains a thermally decomposable leaving group) or a derivative thereof, and / or a general formula (3)

Embedded image (Wherein, Ar ³ , Ar ⁴ and Y are the same as described above (where Y is a group containing a thermally decomposable leaving group)), and a reaction is carried out in an organic solvent used as necessary. Can be synthesized.

In the present invention, the use of the above general formulas (2) and / or (3) is essential, but other than the above general formulas (2) and (3) as long as the effects of the invention are not impaired. Can be used simultaneously with the above tetracarboxylic acid or its derivative and diamine.

Examples of the tetracarboxylic acids other than the general formula (2) include oxydiphthalic acid, pyromellitic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4 ' -Biphenyltetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid,
2,3,6,7-naphthalenetetracarboxylic acid, 1,
4,5,8-naphthalenetetracarboxylic acid, 2,3
5,6-pyridinetetracarboxylic acid, 3,4,9,10
-Perylene tetracarboxylic acid, sulfonyl diphthalic acid,
m-terphenyl-3,3 ', 4,4'-tetracarboxylic acid, p-terphenyl-3,3', 4,4'-tetracarboxylic acid, 1,1,1,3,3,3- Hexafluoro-2,2-bis (2,3- or 3,4-dicarboxyphenyl) propane, 2,2-bis (2,3- or 3,
4-dicarboxyphenyl) propane, 2,2-bis {4 '-(2,3- or 3,4-dicarboxyphenoxy) phenyl} propane, 1,1,1,3,3,3-hexafluoro- 2,2-bis {4 '-(2,3- or 3,4-dicarboxyphenoxy) phenyl} propane, the following general formula (4)

Embedded image (Wherein, R ³ and R ⁴ each represent a monovalent hydrocarbon group, and may be the same or different, and s is an integer of 1 or more). Acids and the like are used, and these are used alone or in combination of two or more.

When the diamine represented by the general formula (3) is not used, the amount of the tetracarboxylic acid represented by the general formula (2) is 10 to 100 of the total amount of the tetracarboxylic acid.
It is preferred to be in the range of mol%. This usage is 1
If it is less than 0 mol%, the i-line transmittance of the polyimide precursor tends to decrease. When the diamine represented by the general formula (3) is used, it may not be used. Examples of the derivative of tetracarboxylic acid include tetracarboxylic acid, tetracarboxylic dianhydride, tetracarboxylic acid chloride and the like. As a reaction partner of the diamine, tetracarboxylic dianhydride is preferable from the viewpoint of reactivity and the like.

Examples of the diamine other than the general formula (3) include, for example, 4,4 '-(or 3,4'-, 3,3'
-, 2,4 '-, 2,2'-) diaminodiphenyl ether, 4,4'- (or 3,4'-, 3,3'-, 2,
4 '-, 2,2'-) diaminodiphenylmethane, 4,
4'- (or 3,4'-, 3,3'-, 2,4'-,
2,2 '-) diaminodiphenyl sulfone, 4,4'-
(Or 3,4'-, 3,3'-, 2,4'-, 2,2 '
-) Diaminodiphenyl sulfide, paraphenylenediamine, metaphenylenediamine, p-xylylenediamine, m-xylylenediamine, o-tolidine, o-tolidinesulfone, 4,4'-methylene-bis- (2,6
-Diethylaniline), 4,4'-methylene-bis-
(2,6-diisopropylaniline), 2,4-diaminomesitylene, 1,5-diaminonaphthalene, 4,4 ′
-Benzophenonediamine, bis- {4- (4'-aminophenoxy) phenyl} sulfone, 1,1,1,3,
3,3-hexafluoro-2,2-bis (4-aminophenyl) propane, 2,2-bis {4- (4'-aminophenoxy) phenyl} propane, 3,3'-dimethyl-4,4 ' -Diaminodiphenylmethane, 3,3 ',
5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis {4- (3'-aminophenoxy) phenyl} sulfone, 2,2-bis (4-aminophenyl)
And propane. These are used alone or in combination of two or more.

The following general formula (5)

Embedded image (Wherein, R ⁵ and R ⁶ each represent a divalent hydrocarbon group, and may be the same or different, and R ⁷ and R ⁸ each represent a monovalent hydrocarbon group, and may each be the same or different. Often, t is an integer of 1 or more.) It is also possible to use an aliphatic diamine such as diaminopolysiloxane.

When the amount of the diamine represented by the general formula (3) is not used, when the tetracarboxylic acid represented by the general formula (2) or a derivative thereof is not used, the amount of the diamine is 10 to 1 of the total amount of the diamine.
It is preferably in the range of 00 mol%. If this amount is less than 10 mol%, the i-line transmittance of the polyimide precursor tends to decrease. When the tetracarboxylic acid represented by the general formula (2) or a derivative thereof is used, it may not be used.

The organic solvent used in the ring-opening polyaddition reaction is preferably an aprotic polar solvent which completely dissolves the polyimide precursor to be produced.
2-pyrrolidone, N, N-dimethylacetamide, N,
N-dimethylformamide, N, N-dimethyl-2-imidazolidone, dimethylsulfoxide, tetramethylurea, hexamethylphosphoric triamide, γ-butyrolactone and the like.

In addition to the aprotic polar solvent,
Ketones, esters, lactones, ethers, halogenated hydrocarbons, hydrocarbons and the like can also be used, for example, acetone, diethyl ketone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone,
Methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate, diethyl carbonate, δ-valerolactone, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, dioxane, chloroform, dichloromethane, 1,2-dichloroethane, , 4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene and the like. These organic solvents are used alone or in combination of two or more.

R ¹ and R ² in the polyimide precursor are O
H or a monovalent organic group. As the monovalent organic group,
Examples thereof include an alkyloxy group and an alkylamino group having 1 to 10 carbon atoms. When used in a negative-type photosensitive resin composition, a carbon-carbon-unsaturated divalent compound is formed through an ionic bond, an ester bond, an amide bond, or the like. The following groups are preferred as the photosensitive group having a heavy bond group.

Embedded image (In the formula, A is a divalent hydrocarbon group, R is a hydrogen atom or a methyl group, and Z ¹ , Z ² and Z ³ are each independently a hydrogen atom or a monovalent hydrocarbon group.) As A, an alkylene group having 1 to 10 carbon atoms is preferable, and as a monovalent organic group among Z ¹ , Z ² and Z ³ , an alkyl group having 1 to 5 carbon atoms is preferable. No.

Among the above-mentioned methods, a method of introducing a carbon-carbon unsaturated double bond through an ionic bond includes a derivative having an amino group of acrylic acid or methacrylic acid (referred to as an acrylate or methacrylate compound having an amino group).
Is preferred. Such compounds include:
For example, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate,
N, N-dimethylaminopropyl methacrylate, N,
N-diethylaminopropyl methacrylate, N, N-
Dimethylaminoethyl acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate, N, N-diethylaminopropyl acrylate, N, N-dimethylaminoethyl acrylamide, N, N-dimethylaminoethyl acrylamide and the like. Can be These are used alone or in combination of two or more.

The amount of the acrylate or methacrylate compound having an amino group to be used is preferably 1 to 200% by weight based on the amount of the polyamic acid before the addition.
More preferably, the content is set to 150% by weight. If the amount is less than 1% by weight, the light sensitivity tends to be poor,
If it exceeds 200% by weight, heat resistance and mechanical properties of the film tend to be inferior.

In the polyimide precursor, when a carbon-carbon unsaturated double bond is introduced via an ester bond, a polyamic acid unsaturated ester is synthesized. In this synthesis,
First, a tetracarboxylic acid diester compound is synthesized.
As a method for synthesizing a tetracarboxylic diester compound,
For example, it can be obtained by mixing the tetracarboxylic dianhydride and the unsaturated alcohol compound in an organic solvent in the presence of a base.

The unsaturated alcohol compound has a carbon number of an alkyl chain such as hydroxymethyl acrylate, hydroxymethyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate and hydroxybutyl methacrylate. 1-10 hydroxyalkyl acrylates or methacrylates are used as preferred.

The molecular weight of the polyimide precursor of the present invention is not particularly limited.
Preferably it is 000. The molecular weight is E
It can be measured by a mold viscometer.

The photosensitive resin composition of the present invention contains the above-mentioned polyimide precursor and, if necessary, a photosensitive agent.
Examples of the polyimide precursor itself to which photosensitivity has been imparted include those in which the side chains R ¹ and R ² of the polyimide precursor are groups having a carbon-carbon unsaturated double bond. In addition, a known method such as a method of adding a monomer reactive with a polyimide precursor, a method of mixing a photosensitizing agent such as a photoacid generator, a photobase generator, or the like to obtain a photosensitive resin composition. As a result, a negative or positive photosensitive resin composition is obtained. Above all, from the viewpoint of easy volatilization of the photosensitive group at the time of ring closure of the thermal imide, ease of production of the photosensitive composition, etc., a negative in which an acrylic compound having an amino group in the carboxylic acid group of the polyimide precursor is introduced by ionic bond. Molded photosensitive resin compositions are preferred.

Further, the photosensitive resin composition of the present invention can contain a photoinitiator, if necessary. Examples of the photoinitiator include Michler's ketone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, 2-t-butylanthraquinone, 2-ethylanthraquinone, 4,4, -bis (diethylamino) benzophenone, acetophenone, benzophenone, and thioxanthone , 2,2-dimethoxy-2-
Phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl- [4- (methylthio)
Phenyl] -2-morpholino-1-propanone, benzyl, diphenyl disulfide, phenanthrenequinone, 2-isopropylthioxanthone, riboflavin tetrabutyrate, 2,6-bis (p-diethylaminobenzal) -4-methyl-4- Azacyclohexanone, N
-Ethyl-N- (p-chlorophenyl) glycine, N-
Phenyldiethanolamine, 2- (o-ethoxycarbonyl) oxyimino-1,3-diphenylpropanedione, 1-phenyl-2- (o-ethoxycarbonyl)
Oxyiminopropan-1-one, 3,3,4,4,-
Tetra (t-butylperoxycarbonyl) benzophenone, 3,3, -carbonylbis (7-diethylaminocoumarin), bis (cyclopentadienyl) -bis-
[2,6-difluoro-3- (pyr-1-yl) phenyl] titanium and the like. These are used alone or in combination of two or more.

The amount of the photoinitiator to be used is preferably 0.01 to 30% by weight based on the amount of the polyimide precursor containing the repeating unit represented by the general formula (1).
More preferably, the content is set to 05 to 10% by weight. If the amount is less than 0.01% by weight, the photosensitivity tends to be poor, and if it exceeds 30% by weight, the mechanical properties of the film tend to be inferior.

The photosensitive resin composition of the present invention may contain an addition polymerizable compound, if necessary. Examples of the addition polymerizable compound include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane diacrylate, and trimethylolpropane. Triacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol methacrylate, Pentaerythritol triacrylate, pentaerythritol tetraacrylate, Data pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, styrene, divinylbenzene, 4-vinyl toluene, 4-vinyl pyridine, N- vinylpyrrolidone, 2-
Hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 1,3-acryloyloxy-2-hydroxypropane, 1,3-methacryloyloxy-2
-Hydroxypropane, methylenebisacrylamide,
N, N-dimethylacrylamide, N-methylolacrylamide and the like can be mentioned. These are used alone or in combination of two or more.

The amount of the addition polymerizable compound used is preferably 1 to 200% by weight based on the amount of the polyimide precursor containing a repeating unit represented by the general formula (1). When the amount is less than 1% by weight, the photosensitive characteristics including solubility in a developer tend to be inferior, and when it exceeds 200% by weight, the mechanical characteristics of the film tend to be inferior.

The photosensitive resin composition of the present invention may contain an azide compound, if necessary. As azide compounds, for example,

Embedded image And the like. These are used alone or in combination of two or more.

The amount of the azide compound used is preferably 0.01 to 30% by weight based on the amount of the polyimide precursor containing a repeating unit represented by the general formula (1).
More preferably, the content is 0.05 to 10% by weight. If the amount is less than 0.01% by weight, the photosensitivity tends to be poor, and if it exceeds 30% by weight, the mechanical properties of the film tend to be inferior.

The photosensitive resin composition of the present invention may contain a radical polymerization inhibitor or a radical polymerization inhibitor in order to enhance the stability during storage. As the radical polymerization inhibitor or the radical polymerization inhibitor, for example,
p-methoxyphenol, diphenyl-p-benzoquinone, benzoquinone, hydroquinone, pyrogallol, phenothiazine, resorcinol, orthodinitrobenzene, paradinitrobenzene, metadinitrobenzene, phenanthraquinone, N-phenyl-1-naphthylamine, N-phenyl-2- Examples include naphthylamine, cuperon, phenothiazine, 2,5-toluquinone, tannic acid, parabenzylaminophenol, nitrosamines and the like. These are used alone or in combination of two or more.

The amount of the radical polymerization inhibitor or the radical polymerization inhibitor used is preferably 0.01 to 30% by weight based on the amount of the polyimide precursor containing the repeating unit represented by the general formula (1). More preferably, it is 0.05 to 10% by weight. The amount used is 0.01% by weight
If it is less than 30, the stability during storage tends to be inferior, and 30
If the amount is more than 10% by weight, light sensitivity and mechanical properties of the film tend to be poor.

When producing a positive photosensitive resin composition, a compound which generates an acid by light is generally used together with a polyimide precursor. The compound that generates an acid by light is a photosensitizer, and has a function of generating an acid and increasing the solubility of the irradiated portion in an aqueous alkaline solution. Examples of the type include an o-quinonediazide compound, an allyldiazonium salt, a diallyliodonium salt, and a triallylsulfonium salt. There is no particular limitation, but an o-quinonediazide compound is preferred because of its high sensitivity. The component that generates an acid by light is preferably 5 to 100 parts by weight, based on 100 parts by weight of the polyimide precursor having the repeating unit represented by the general formula (1), from the viewpoint of the film thickness and sensitivity after development. More preferably, it is used in an amount of 10 to 40 parts by weight.

The photosensitive resin composition of the present invention can be obtained in a solution state by dissolving a polyimide precursor having a repeating unit represented by the above general formula (1) in a solvent and then dissolving other components. it can.

As the solvent, for example, N-methyl-
2-pyrrolidone, N, N-dimethylformamide, N,
N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, tetramethylene sulfone,
Aprotic polar solvents such as γ-butyrolactone, cyclohexanone and cyclopentanone are used alone or in combination of two or more.

The photosensitive resin composition of the present invention may further contain an organic silane compound, an aluminum chelate compound, a silicon-containing polyamic acid, etc. in order to enhance the adhesion of the cured film to the substrate. Examples of the organic silane compound include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the like. Can be Examples of the aluminum chelate compound include aluminum tris (acetylacetonate) and aluminum acetylacetate diisopropylate.

The photosensitive resin composition of the present invention is applied onto a base material such as a silicon wafer, a metal substrate, a ceramic substrate or the like by an immersion method, a spray method, a screen printing method, a spin coating method or the like, and removes most of the solvent. By heating and drying, a coating film having no tackiness can be obtained. Although there is no particular limitation on the thickness of this coating film, from the viewpoint of circuit characteristics and the like, it is 4 to 50 μm.
m, more preferably 6 to 40 μm, particularly preferably 10 to 40 μm, and most preferably 20 to 35 μm. After irradiating actinic rays or actinic rays on the coating film through a mask on which a desired pattern is drawn, for example, by irradiating it with a pattern, the unexposed portion is developed and dissolved with an appropriate developing solution to be removed. Thereby, a desired relief pattern can be obtained.

The photosensitive resin composition of the present invention is suitable for use in an i-ray stepper. As an actinic ray or actinic ray to be irradiated, for example, an ultra-high pressure mercury lamp is used in addition to the i-ray stepper. Contact / proximity exposure machine, mirror projection exposure machine, g-line stepper,
Other ultraviolet rays, visible light sources, X-rays, electron beams and the like can also be used.

As a developing solution, for example, a good solvent (N, N
-Dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, etc.), a mixed solvent of the above good solvent and a poor solvent (lower alcohol, ketone, water, aromatic hydrocarbon, etc.), a basic solution ( Aqueous solution of tetramethylammonium hydroxide, aqueous solution of triethanolamine, etc.). After the development, it is preferable to perform rinsing with water or a poor solvent, if necessary, and to dry at about 100 ° C. to stabilize the pattern.

Further, by heating the relief pattern, imide ring closure and elimination of the thermally decomposable leaving group can be achieved, and a patterned polyimide resin film can be formed. The heating temperature at this time is preferably from 80 to 450 ° C. If the heating temperature is lower than 80 ° C. or higher than 450 ° C., the mechanical and thermal properties of the polyimide film tend to decrease. The heating time at this time is preferably set to 10 minutes to 100 minutes. If the heating time is less than 10 minutes or more than 100 minutes, the mechanical properties and thermal properties of the polyimide film tend to decrease.

As described above, the photosensitive resin composition of the present invention can be used for a surface protective film, an interlayer insulating film and the like of electronic parts such as a semiconductor device and a multilayer wiring board. The electronic component of the present invention is not particularly limited except that it has a surface protective film and an interlayer insulating film formed using the composition, and can have various structures.

As an example of the electronic component of the present invention, an example of a semiconductor device manufacturing process will be described below. FIG. 1 is a manufacturing process diagram of a semiconductor device having a multilayer wiring structure. In the figure, a semiconductor substrate such as a Si substrate having a circuit element is covered with a protective film 2 such as a silicon oxide film except for a predetermined portion of the circuit element, and a first conductor layer is formed on the exposed circuit element. . A film 4 of a polyimide resin or the like as an interlayer insulating film is formed on the semiconductor substrate by a spin coating method or the like (step (a)).

Next, a photosensitive resin layer 5 of a chlorinated rubber type or a phenol novolak type is formed on the interlayer insulating film 4 by spin coating, and a predetermined portion of the interlayer insulating film 4 is exposed by a known photolithography technique. Window 6A is provided as described above (step (b)). The interlayer insulating film 4 in the window 6A is selectively etched by a dry etching means using a gas such as oxygen or carbon tetrafluoride, and a window 6B is opened. Next, the photosensitive resin layer 5 is completely removed by using an etching solution that corrodes only the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B (step (c)).

Further, using a known photolithography technique,
The conductor layer 7 is formed, and the electrical connection with the first conductor layer 3 is made completely (step (d)). When a multilayer wiring structure of three or more layers is formed, the above steps are repeated to form each layer.

Next, a surface protection film 8 is formed. In the example of this figure, the surface protective film is coated with the photosensitive polymer composition by a spin coating method, dried, and irradiated with light from a mask on which a pattern for forming a window 6C is drawn on a predetermined portion. A pattern is formed by developing with an aqueous solution, and heated to form a polyimide film. This polyimide film protects the conductor layer from external stress, α-rays and the like, and the resulting semiconductor device has excellent reliability. In the above example, the interlayer insulating film can be formed using the photosensitive resin composition of the present invention.

[0058]

The present invention will be described below with reference to examples. Synthesis Examples 1 to 3 A diamine component and N-methyl-2-pyrrolidone shown in Table 1 were added to a 100-ml flask equipped with a stirrer and a thermometer and dissolved by stirring at room temperature. The acid component was added and stirred for 24 hours to obtain a viscous polyimide precursor solution. Further, the solution was adjusted to a viscosity of 10
The solution was heated at 70 ° C. until it reached 0 poise (solid content 25% by weight), and the polyimide precursor solutions (PAA-1 to PAA-
3). In addition, each use amount and weight average molecular weight of the diamine component, the acid component, and N-methyl-2-pyrrolidone,
The results are shown in Table 1.

The molecular weight was measured using an E-type viscometer (EHD type, manufactured by Toki Sangyo Co., Ltd.) at a temperature of 25 ° C. and a rotation speed of 2.5 rpm. A dried solution of the obtained polyimide precursor was subjected to an infrared absorption spectrum (JIR-100, manufactured by JEOL Ltd.) by the KBr method.
As a result, the absorption of C = O of the amide group at around 1600 cm ^-1 and the absorption of NH at around 3300 cm ^-1 were confirmed.

[0060]

[Table 1]

Examples 1 to 3 Each of the polyimide precursors (PAA) obtained in Synthesis Examples 1 to 3
−1 to PAA-3), 0.027 g of 2,6-bis (4′-azidobenzal) -4-carboxycyclohexanone (CA) and 4,4′-bis (diethylamino) benzophenone (EAB) with respect to 10 g of the solution of 0.027 g and 0.054 g of 1-phenyl-2- (o-ethoxycarbonyl) oxyiminopropan-1-one (PDO) were added, and dimethylaminopropyl methacrylate (MDA) equivalent to the carboxyl group of the polyimide precursor was added.
P) was added thereto, followed by stirring and mixing to obtain a uniform photosensitive resin composition solution used in Examples 1 to 3.

The obtained photosensitive resin composition solution was filtered through a filter, and each solution was spin-coated on a silicon wafer. Next, using a hot plate, the coating was heated at 100 ° C. for 150 seconds to form a 23 μm coating film, and then subjected to pattern masking and exposure with an i-line stepper. This was further heated at 100 ° C. for 60 seconds, and paddle-developed using a mixed solution of N-methyl-2-pyrrolidone / water (75/25 (weight ratio)). 20
By heating at 0 ° C. for 30 minutes and at 350 ° C. for 60 minutes, a polyimide resin relief pattern was obtained.

The transmittance of each of the polyimide precursors (PAA-1 to PAA-3) obtained in Synthesis Examples 1 to 3, the coefficient of thermal expansion of the polyimide film obtained above, the residual stress on the silicon wafer, and the relief The resolution of the pattern was evaluated by the following method, and the evaluation results are shown in Table 2.

The transmittance was determined by spin-coating the obtained resin solution of each of the polyimide precursors (PAA-1 to PAA-7) and drying at 85 ° C. for 3 minutes and further at 105 ° C. for 3 minutes. The film (10 μm) was measured with a spectrophotometer.
The coefficient of thermal expansion was measured by TMA under the conditions of a heating rate of 10 ° C./min and a load of 10 g for a polyimide film having a thickness of 10 μm. Residual stress is obtained by forming a polyimide film on a 6-inch wafer and using a Tencor stress measuring device (FLX-232).
0). The resolution was evaluated as the minimum size of a developable through hole using a through hole test pattern.

[0065]

[Table 2]

[0066]

The polyimide precursor of the present invention has good i-line transmittance by itself and can provide a polyimide resin having low thermal expansion after imidization. Further, the photosensitive resin composition of the present invention has good i-line transmittance by itself and can provide a polyimide resin having low thermal expansion after imidization.

Further, the photosensitive resin composition of the present invention exhibits the above-mentioned effects, and has high sensitivity to i-line. Further, the photosensitive resin composition of the present invention exhibits the above-mentioned effects, and gives a more favorable pattern shape.

According to the method for producing a pattern of the present invention,
By using a polyimide resin having a low thermal expansion property after imidization while having good i-line transmittance as a polyimide precursor, a pattern having a very small residual stress in a good pattern shape can be formed. Further, the electronic component of the present invention has extremely small residual stress after the formation of the polyimide resin film, and is excellent in reliability.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a semiconductor device having a multilayer wiring structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1: Semiconductor substrate, 2: Protective film, 3: 1st conductor layer,
4 ... interlayer insulating film layer, 5 ... photosensitive resin layer, 6A, 6B, 6
C: window, 7: second conductor layer, 8: surface protective film layer.

Continued on the front page F-term (reference) 4J002 CM041 GP03 4J043 PA02 PA04 PA19 PC015 PC035 PC075 PC085 PC145 PC165 QB15 QB26 RA06 RA35 SA06 SB01 SB03 TA22 TB01 TB03 UA121 UA131 UA132 UA141 UA142 UA252 UA262 UA362 UB011 UB 012 UB011 UB151 UB152 UB291 UB301 UB302 UB351 UB352 WA09 WA16 WA22 XA16 XA19 YA06 YB07 YB08 YB19 YB32 ZA46 ZA60 ZB02 ZB50

Claims (10)

[Claims] 1. A compound of the general formula (1) (Wherein, Ar ¹ , Ar ² , Ar ³ and Ar ⁴ are each independently an organic group having an aromatic ring, X and Y are each independently a single bond or a divalent group, R ¹ and R ² is independently OH or a monovalent organic group, and Ar ¹ , Ar ² , Ar
³ and at least one of Ar ⁴ has a thermally decomposable leaving group). 2. The polyimide precursor according to claim 1, wherein the thermally decomposable leaving group is a carboxyl group, an acyloxy group, an alkoxycarbonylamino group, an alkylaminocarbonyloxy group or an alkylazo group. 3. The polyimide precursor according to claim 1, wherein X and Y are a single bond or a p-phenylene group. 4. A 1 in the general formula (1) ^{R 1} and ^{R 2} in
4. The polyimide precursor according to claim 1, wherein the valence organic group is a photosensitive group having a carbon-carbon unsaturated double bond. 5. A photosensitive resin composition comprising the polyimide precursor according to claim 1, 2, 3, or 4. 6. A compound represented by R ¹ and R ² in the general formula (1)
The photosensitive resin composition according to claim 5, wherein the valent organic group is a photosensitive group having a carbon-carbon unsaturated double bond bonded to a carboxyl group via a salt complex. 7. The photosensitive resin composition according to claim 6, wherein a monovalent organic group for R ¹ and R ² is provided by using a derivative of acrylic acid or methacrylic acid having an amino group. 8. A step of applying the photosensitive resin composition according to claim 5, 6 or 7 on a support substrate and drying, exposing,
A method for producing a relief pattern, comprising a step of developing and a step of thermally desorbing a thermally decomposable leaving group of a polyimide precursor to form a polyimide. 9. The method for producing a relief pattern according to claim 8, wherein the step of exposing is performed using i-line as an exposure light source. 10. An electronic component having a pattern layer obtained by the method according to claim 9.