JP2812774B2 - Photosensitive resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a photosensitive resin composition which is excellent in optical characteristics such as sensitivity to visible light or ultraviolet light and phenomena, and which is excellent in heat resistance.

(Prior art) Conventionally, polyimide having excellent heat resistance and excellent electrical insulation properties and mechanical strength has been used for a surface protection film, an interlayer insulating film and the like of a semiconductor element. Recently, a technique for imparting photosensitivity to polyimide itself in order to simplify complicated steps has attracted attention.

For example, A polyimide-precursor composition having a photosensitive group provided with an ester group having a structure as shown in (JP-A-55-30207) or a carbon-carbon double which can be duplicated or polymerized by actinic radiation to a polyamic acid. A composition to which a compound containing a bond and an amino group or a quaternized salt thereof is added (for example,
No. 145794) is known.

These are all dissolved in an appropriate organic solvent, applied and dried in a varnish state, irradiated with ultraviolet light through a photomask, and subjected to a phenomenon, a rinsing treatment to obtain a desired pattern, and further subjected to a heat treatment to obtain a polyimide. It is a coating.

The use of polyimide with photosensitivity not only has the effect of simplifying the pattern creation process, but also does not require the use of highly toxic etchants, so it is safe and excellent in terms of pollution. It is expected that this technology will become even more important in the future.

However, when such a conventional photosensitizing technique is applied, a polyimide precursor composition having a photosensitive group provided with an ester group only has a low heat resistance of the cured film because the photosensitive group is not easily scattered during thermosetting. It was difficult to use in the semiconductor industry.

In addition, in a composition in which a compound containing a carbon-carbon double bond and an amino group or a quaternized salt thereof that can be dimerized or polymerized by actinic radiation is added to a polyamic acid, the sensitivity is extremely low even when irradiated with infrared rays, In addition, the viscosity of the varnish changes greatly during storage, so that it is insufficient for use in a manufacturing process usually used in the semiconductor industry.

(Problems to be Solved by the Invention) An object of the present invention is to provide a highly sensitive photocurable by mixing an acrylate compound having a carboxy group and a photosensitizer in a polyamic acid compound, Another object of the present invention is to provide a photosensitive resin composition in which the viscosity of the composition does not change during storage and the cured film has excellent heat resistance, heat cycle resistance, heat shock resistance, moisture resistance and the like.

(Means for Solving the Problems) The present inventors have conducted intensive studies to solve these problems which could not be overcome by the conventional technology. (A) The following formula (I) (Wherein R ₁ and R ₂ are the same or different aromatic cyclic groups, and R ₃ is -C
The _{2 H 4 N (CH 3)} 2 or _{-C 2 H 4 N (C 2} H 5) 2, m is 6 to 20
A polyamic acid compound represented by the following formula (II) having one or two acrylic or methacrylic groups: (Wherein X is -H or -CH ₃ radical, Y is a phenyl group, Z is -C
_{2 H 4 -, - C 3} H 6 -, O, P is 1 or 2 showing a) (C) High reliability by maximum absorption wavelength (.lambda.max) is an essential component sensitizer is 330~555nm Have been found that it is possible to obtain a photosensitive resin composition having the formula (1), and have completed the present invention.

(Operation) It is desirable that the polyamic acid compound (A) in the present invention becomes an aromatic polyimide after heat curing in order to improve the heat resistance of the polyimide film. Such a polyamic acid compound (A) includes γ-butyrolactone, N-methyl-
It is synthesized by condensation of a diester of tetracarboxylic acid obtained by reacting an amino alcohol with an aromatic tetracarboxylic anhydride in a polar solvent such as 2-pyrrolidone or N, N-dimethylacetamide, and a diamine. In order to improve the sensitivity, the polyamic acid compound (A) preferably has a high molecular weight.
The temperature is preferably 50 ° C, more preferably -10 ° C to 30 ° C. The dicarboxylic acids and the diamines are moles of 0.8
Preferably it is ~ 1.1.

The aromatic cyclic groups R ₁ and R ₂ in the following formula (I) are, for example, a benzene ring, (Wherein R ₁ and R ₂ are the same or different aromatic cyclic groups, and R ₃ is -C
The _{2 H 4 N (CH 3)} 2 or _{-C 2 H 4 N (C 2} H 5) 2, m is 6 to 20
A naphthalene ring). Also m
Is preferably 6 or less and 200 or less. If it is less than 6, sensitivity decreases, and if it exceeds 200, it is difficult to synthesize industrially. Examples of the aromatic tetracarboxylic dianhydride used for synthesizing the polyamic acid compound of the above formula (1) include the following acid anhydrides. Pyromellitic dianhydride, 3,
3 ′, 4,4′benzophenonetetracarboxylic dianhydride,
2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,
3 ', 4,4'-diphenyltetracarboxylic dianhydride, 2,
2 ', 3,3'-diphenyltetracarboxylic dianhydride, 2,2
3,3 ', 4'-diphenyltetracarboxylic dianhydride, 3,
3 ', 4,4'-p-terphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride,
2,2-bis (3,4-dicarboxydiphenyl) ether dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8, -tetracarboxylic acid Dianhydride, 4,8-dimethyl-1,2,3,5,6,7, -hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6,-
Dichloronaphthalene, 1,4,5,8-tetracarboxylic dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1,2,9,10- Tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, 2,2-bis (2, 5-dicarboxyphenyl)
Propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxy (Carboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, benzene-1,2,3,4-butanetetracarboxylic dianhydride, thiophene-2,3,4,5
-Tetracarboxylic dianhydride and the like.

In addition to the above-mentioned aromatic tetracarboxylic dianhydride, a silicone-based tetracarboxylic dianhydride or an aliphatic tetracarboxylic dianhydride can of course be used in combination for imparting various properties.

Examples of the amino alcohol used for synthesizing the polyamic acid compound include, but are not limited to, 2-dimethylaminoethanol, 2-diethylaminoethanol, 3-dimethylaminopropanol, and 3-diethylaminopropanol.

The aromatic diamine component used for synthesizing the polyamic acid compound may be one kind or a mixture of two or more kinds. Examples of the aromatic diamine used include m-phenylenediamine, p-phenylenediamine, and 4,4′-diamino. Diphenylpropane, 4,4'-diaminodiphenylmethane, benzidine, 4,4'-diaminodiphenylsulfide, 4,4'-diaminophenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylether, 3,4 3'-diaminodiphenyl ether, 4,4 '
-Diamino-p-terphenyl, 2,6-diaminopyridine, bis (4-aminophenyl) phosphine oxide,
Bis (4-aminophenyl) -N-methylamine, 1,5
-Diaminonaphthalene, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybendicine, 2,4-
Bis (β-amino-t-butyl) -toluene, bis (p
-Β-amino-t-butylphenyl) ether, p-bis (2-methyl-4-aminobentyl) benzene, p-
Bis (1,1-dimethyl-5-aminobentyl) benzene, 2,4-diaminotoluene, m-xylylenediamine, p-xylylenediamine and the like. As the diamine component used in the present invention, a silicone-based diamine or an aliphatic diamine can of course be used in combination with the above-described aromatic diamine to impart various properties.

The polyamic acid compound thus obtained has no carboxyl group unlike polyamic acid, and therefore has no intermolecular interaction and has excellent viscosity stability of the varnish during storage.

The acrylate (B) in the present invention is represented by the following formula (II) (Wherein X is -H or -CH ₃ radical, Y is a phenyl group, Z is -C
₂ H ₄ —, —C ₃ H ₆ —, O, P represent 1 or 2) An acrylate compound having one or two acrylic or methacrylic groups and a carboxylic acid group in one molecule. Acrylic acid, methacrylic acid,
Ethyl phthalate-2-acrylate, ethyl phthalate-
2-Methacrylate propyl phthalate-2-acrylate, propyl phthalate-2-methacrylate ethyl trimellitate-2-acrylate, ethyl trimellitate-2-methacrylate diethyl pyromellitate-2-diacrylate, diethyl pyromellitate- Examples include, but are not limited to, 2-dimethacrylate.

The sensitizer (C) in the present invention is a compound having an absorption maximum wavelength (λmax) at 330 to 500 nm.

If λmax is less than 330 nm, light is absorbed by the polyamic acid compound, and a photoreaction cannot be performed. On the other hand, if it exceeds 500 nm, a light reaction occurs with visible light, and it is necessary to set a work place in a shielded room. The sensitizer of the present invention, for example, However, the present invention is not limited to these.

 Hereinafter, the method of using the composition of the present invention will be described.

The composition of the present invention and all of the compositions in the composition are dissolved in a solvent capable of dissolving and applied onto a predetermined substrate.

The solvent is preferably a polar solvent, for example, N-methyl-pyrrolidone, dimethylacetamide, γ-butyrolactone, dimethylformamide and the like.

In order to enhance the adhesion to a substrate such as a silicon wafer, a silane coupling agent such as triethoxyvinylsilane, tri (methoxyethoxy) vinylsilane, and γ-glycidoxypropyltrimethoxysilane is added.

As a method of applying the solution on the substrate, the solution obtained as described above is applied to the substrate by a spin coater, a bar coater, a screen printing method, or the like. The substrate is made of metal, glass, silicon, glass epoxy, or the like.

Next, the coating film thus obtained is dried by air drying, heating drying, vacuum drying, or the like, and then exposed. At this time, the active light used includes, for example, visible light, ultraviolet light, X-ray, electron beam and the like, and visible light and ultraviolet light are preferable.

After exposure in this way, to remove unirradiated parts,
The phenomenon is performed using an immersion method or a spray method. Phenomena used at this time include, for example, N-methylpyrrolidone, N,
An aprotic polar solvent such as N'-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide and the like may be used alone, or as a second component thereof, for example, alcohols such as ethanol and isopropanol, hexane and cyclohexane And a solvent such as an aliphatic hydrocarbon compound such as an aromatic hydrocarbon compound such as toluene and xylene. Further, it is preferable to rinse immediately after the development with a solvent such as that described as the second component.

The thus obtained image containing polyamide as a main component is used for applications such as a cured resist, an insulating film and a protective film.

At this time, if necessary, treatments such as removal of unnecessary components by heating and conversion of the chemical structure of the polyamide are performed.

EXAMPLES Next, the present invention according to examples will be described in more detail.

Example 1 21.8 g (0.1 mol) of pyromellitic anhydride, 36.8 g (0.207 mol) of 2-dimethylaminoethanol, and 19.0 g (0.1 mol) of p-toluenesulfonic acid hydrate were N-methyl-2-
The reaction is carried out at room temperature for 4 hours in 200 ml of pyrrolidone. Next, a solution of 41.2 g (0.2 mol) of dihexylcarbodiimide in N-methyl-2-pyrrolidone is slowly added dropwise, and the mixture is reacted for 75 minutes.

Then, 4,4'-diaminodiphenyl ether 18g (0.9mo
l) was added, and the mixture was reacted for 4 hours. After that, the precipitate was filtered, and the filtrate was added to ethanol of 5 to obtain a yellow-white polyimide oxide compound. 100 weight parts of this polyimide acid compound
-Methyl-2-pyrrolidone was dissolved in 400 parts by weight, and 80 parts by weight of methyl methacrylate and 5 parts by weight of a photosensitizer Michler's ketone were stirred at room temperature for 3 hours, dissolved and mixed.

The obtained solution was applied on an aluminum plate with a spinner and dried at 80 ° C. for 1 hour with a dryer to obtain a film.

In this film, Kodak's Photographic Step Tablet No.2, 21 steps (In the above Grescale,
Each time the number of steps increases, the amount of transmitted light increases Therefore, the sensitivity increases as the number of remaining steps of the coating after development increases. ), Irradiated with ultraviolet rays of 500 mJ / cm ² , developed with a developing solution of N-methylpyrrolidone 60 parts by weight and methanol 40 parts by weight, and further rinsed with isopropyl alcohol, and found to have a sensitivity of 200 mJ / cm ^2. It was found to be highly sensitive.

Next, exposure and development were performed in the same manner as in the patterning experiment described above using a mask for resolution measurement made by letterpress printing (letterpress test chart No. 1). Did not.

 The pattern had a resolution of 10 μm.

Further, the temperature at which the thermal decomposition of the polyimide film started was 400 ° C. as measured with a differential thermobalance. The viscosity change of the obtained photosensitive resin composition was measured to be +5.
There was no change in viscosity for 30 days under the storage conditions of ° C.

The photosensitive resin composition thus obtained had the effects of high sensitivity, high heat resistance, and excellent varnish preservability at the same time.

 Table 1 shows the evaluation results.

Example 2 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride 32.2 g (0.1 mol), 2-diethylaminoethanol 20.
6g (0.2mol), p-phenylenediamine 10.8g (0.1mol)
In the same manner as in Example 1 to obtain a polyamic acid compound.

10 parts by weight of this polyamic acid compound was dissolved in 300 parts by weight of r-butyrolactone, and 90 parts by weight of diethyl-2-diacrylate pyromellitate and 10 parts by weight of Michler's ketone photosensitizer were dissolved and mixed. The obtained photosensitive resin composition was evaluated in the same manner as in Example 1. The results are shown in Table 1.

The obtained photosensitive resin composition was highly sensitive and further excellent in heat resistance.

Example 3 2,3,3 ', 4'-diphenyltetracarboxylic dianhydride 1
8.4 g (0.1 mol), 2-dimethylaminoethanol 35.8 g
(0.201 mol), 8.6 g of p-phenylenediamine (0.08mo
l) was performed in the same manner as in Example 1 to obtain a polyamic acid compound.

100 parts by weight of this polyamic acid compound was dissolved in 200 parts by weight of N, N-dimethylacetamide, and 70 parts by weight of ethyl trimellitate-2-acrylate and 10 parts by weight of a photosensitizer Michler's ketone were dissolved and mixed.

The obtained photosensitive resin composition was evaluated in the same manner as in Example 1. The results are shown in Table 1.

The obtained photosensitive resin composition has high sensitivity and further has excellent storage stability of a heat-resistant varnish.

Comparative Example 1 A polyamic acid solution was prepared by reacting 290 g (0.9 mol) of 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride and 200 g (0.1 mol) of 4,4'-diaminodiphenyl ether in N-methylpyrrolidone. I got

80 parts by weight of N, N-dimethylaminoethyl methacrylate and 5 parts by weight of Michler's ketone were added to 100 parts by weight of the obtained polyamic acid solution (solid content of polyamic acid) at room temperature.
The mixture was stirred for a period of time, dissolved and reacted to obtain a photosensitive resin composition.

The obtained photosensitive resin composition has a strong intermolecular interaction because it has a carboxyl group in the molecule, and its viscosity changes greatly during storage due to the influence of moisture and the like, and its practicality is low. I understood.

Comparative Example 2 21.8 g of pyromellitic anhydride, 27.0 g of 2-hydroxyethyl methacrylate and 100 ml of r-butyrolactone were added, and 17.0 g of pyridine was added with stirring under ice cooling. 8 at room temperature
After stirring for 4 hours, dicyclohexylcarbodiimide 41.2
g of r-butyrolactone in 40 ml was added under ice cooling over 10 minutes, followed by 16.0 g of 4,4'-diaminodiphenyl ether.
Was added for 15 minutes, the mixture was stirred under ice cooling for 3 hours, and the precipitate was filtered. The obtained solution was added to 10 parts of ethanol to obtain a yellowish white powder. 100 parts by weight of this powder, 40 g of ethylene glycol diacrylate, 0.4 g of Michler's ketone, 2.0 g of benzophenone, and 4.0 g of benzyldimethyl ketal were dissolved in 200 g of N-methylpyrrolidone to obtain a photosensitive resin composition.

The obtained photosensitive resin composition was processed in the same manner as in Example 1 to form a pattern. The thermal decomposition onset temperature of this polyimide film was 330 ° C.

In the photosensitive resin composition thus obtained, since the polyimide compound and the photosensitive group are bound by a covalent bond, the photosensitive group is hardly scattered and the heat resistance is poor.

 Table 1 shows the evaluation results.

(Effect of the Invention) A photosensitive polyamic acid synthesized by blending an acrylic compound having an amino group is easily affected by moisture and the like because of strong intermolecular interaction, and the viscosity during storage greatly changes. Further, even if light is irradiated for patterning, the sensitivity is low, so that it is not preferable for being suitable for the semiconductor industry.

However, in the present invention, since the polyimide acid compound (A) does not contain a carboxy group, there is no intermolecular interaction and the viscosity during storage is stable. In addition, since a monofunctional acrylate (B) and a sensitizer (C) having an absorption maximum wavelength (λmax) of 330 to 500 nm are blended, as a result, crosslinking is caused by an extremely small amount of light irradiation and high sensitivity is obtained.

Furthermore, the heat resistance of the polyimide film after heat curing is such that the acrylate (B) is only compounded in the polyimide compound (A) and is not introduced into the polyimide skeleton by a covalent bond. , And the heat resistance inherent to the aromatic polyimide is maintained, and a very excellent effect of exhibiting high heat resistance can be obtained at the same time.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-175854 (JP, A) JP-A-59-15449 (JP, A) JP-A-61-73740 (JP, A) JP-A-63-175 27834 (JP, A) JP-A-2-142828 (JP, A) JP-A-2-96168 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03F 7/038 G03F 7 / 027 C08G 73/10 C08L 79/08

Claims (1)

(57) [Claims] (A) The following formula (I) (Wherein R ₁ and R ₂ are the same or different aromatic cyclic groups, and R ₃ is -C
The _{2 H 4 N (CH 3)} 2 or _{-C 2 H 4 N (C 2} H 5) 2, m is 6 to 20
A polyamic acid compound represented by the following formula (I): (B) acrylic acid, methacrylic acid, or the following formula (I) having one or two acryl or methacryl groups in one molecule;
I) Acrylate (Wherein X is -H or -CH ₃ radical, Y is a phenyl group, Z is -C
_{2 H 4 -, - C 3} H 6 -, O, P is 1 or 2 showing a) (C) maximum absorption wavelength (.lambda.max) is characterized in that as an essential component sensitizer is 330~500nm Photosensitive resin composition.