JP2002278051A - Positive type photosensitive resin composition and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive type photosensitive resin composition giving a light-colored film after curing and less liable to discoloration even in a heat treatment process after curing. SOLUTION: The positive type photosensitive resin composition comprises 100 pts.wt. polyamide (A) of formula (I) having phenolic hydroxyl groups, 1-100 pts.wt. photosensitive diazoquinone compound (B) and 1-20 pts.wt. phosphorus compound (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photosensitive resin composition having a pale color after curing and having little discoloration in a heat treatment process after curing.

[0002]

2. Description of the Related Art Conventionally, a polyimide resin having excellent heat resistance and excellent electrical and mechanical properties has been used as a surface protective film and an interlayer insulating film of a semiconductor element. There is a demand for remarkable improvement in heat cycle resistance and heat shock resistance due to the increase in size, increase in size, thinner and smaller package, shift to surface mounting by solder reflow, etc., and further high-performance resin is required. It has become On the other hand, a technique for imparting photosensitivity to the polyimide resin itself has attracted attention, and examples thereof include a photosensitive polyimide resin represented by the following formula (II).

[0003]

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When this is used, a part of the pattern forming process can be simplified, which has the effect of shortening the process.
Since a solvent such as methyl-2-pyrrolidone is required, there is a problem in safety and handling. Therefore, recently, a positive photosensitive resin that can be developed with an alkaline aqueous solution has been developed. For example, Japanese Patent Publication No. 1-46862 discloses a positive photosensitive resin composed of a polybenzoxazole precursor and a diazoquinone compound. It has high heat resistance, excellent electrical properties and fine workability, and has the potential not only as a wafer coat but also as an interlayer insulating resin. The mechanism of development of this positive photosensitive resin is that the unexposed part of the diazoquinone compound is insoluble in an aqueous alkali solution, but the exposure causes the diazoquinone compound to undergo a chemical change and become soluble in the aqueous alkali solution.
By utilizing the difference in solubility between the exposed portion and the unexposed portion to dissolve and remove the exposed portion, it becomes possible to form a coating film pattern of only the unexposed portion.

After development, the positive photosensitive resin disclosed in Japanese Patent Publication No. 1-46862 is heated to about 300-400 ° C.
Is a general process of performing a heat treatment at the temperature described above to close the ring (curing) and convert the film into a film having excellent thermal stability. But,
When this curing is performed, there is a problem that the polybenzoxazole resin and the diazoquinone compound are decomposed and oxidized, and the film turns black. Further, in the semiconductor manufacturing process, various heat treatments are also performed after the curing process of the polybenzoxazole resin. For example, in the case of the LOC structure, L
The lead frame with the OC tape is pressure-bonded to the chip at a high temperature of 350 to 450 ° C. At that time, the polybenzoxazole resin coated on the chip also turns black. When the color changes, recognition failure occurs during the subsequent wire bonding. Therefore, a positive photosensitive resin composition in which the color of the cured film is light and the discoloration is small in the heat treatment process after the curing is desired.

[0006]

The present invention relates to a positive photosensitive resin composition in which the color of a cured film is light and the discoloration is small even in a heat treatment process after curing.

[0007]

Means for Solving the Problems 100 parts by weight of a polyamide (A) represented by the general formula (I), 1 to 100 parts by weight of a photosensitive diazoquinone compound (B), and a phosphorus compound (C)
It is a positive photosensitive resin composition comprising 0.5 to 20 parts by weight. Also, it is a semiconductor device manufactured using the same.

[0008]

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[0009]

DETAILED DESCRIPTION OF THE INVENTION The polyamide of the formula (I) is synthesized from a diamine having the structure X, a dicarboxylic acid having the structure Y and a carboxylic acid derivative further having the structure E.
When this polyamide is heated at about 300 to 400 ° C., it undergoes dehydration and ring closure to change to a heat-resistant resin called polybenzoxazole.

X of the polyamide (I) of the present invention is, for example,

Embedded image Etc., but are not limited to these.

[0011] Of these, particularly preferred are:

Embedded image It is more chosen.

Further, Y in the formula (I) is, for example,

Embedded image Etc., but are not limited to these.

Among these, particularly preferred are:

Embedded image It is more chosen.

E in the formula (I) represents a polyamide synthesized by reacting a dicarboxylic acid derivative having the structure of Y with a diamine having the structure of X, and then ending the terminal amino group with at least one alkenyl group or alkynyl group. The reaction is carried out by reacting a carboxylic acid derivative having the same, and the terminal is blocked. Examples of the carboxylic acid derivative include 5-norbornene-2,3-dicarboxylic anhydride, maleic anhydride and the like.
Norbornene-2,3-dicarboxylic anhydride is preferred.

Further, Z in the formula (I) is, for example,

Embedded image Etc., but are not limited to these.

Z in the formula (I) is used when even higher adhesion is required, but the proportion b used is up to 40.0 mol%. If it exceeds 40.0 mol%, the solubility of the resin is extremely reduced, and undeveloped portions (scum) are generated, so that pattern processing cannot be performed. In using these X, Y, E, and Z, one type or a mixture of two or more types may be used.

The photosensitive diazoquinone compound used in the present invention is a compound having a 1,2-benzoquinonediazide or 1,2-naphthoquinonediazide structure, and is disclosed in US Pat. Nos. 2,772,972 and 2,797,213.
No. 3,669,658. For example, the following are mentioned.

[0018]

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[0019]

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Among these, the following are particularly preferred.

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The compounding amount of the photosensitive diazoquinone compound (B) to the polyamide (A) is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the polyamide. It is bad, conversely 100
If the amount is more than 10 parts by weight, the tensile elongation of the film obtained after curing is significantly reduced.

A dihydropyridine derivative can be added to the positive photosensitive resin composition of the present invention, if necessary, to enhance the photosensitive characteristics. Examples of the dihydropyridine derivative include, for example, 2,6-dimethyl-3,5-diacetyl-4- (2′-nitrophenyl) -1,4-dihydropyridine, 4- (2′-nitrophenyl) -2,6-dimethyl -3,5-dicarbethoxy-1,4-dihydropyridine, 4- (2 ', 4'-dinitrophenyl) -2,
6-dimethyl-3,5-dicarbomethoxy-1,4-dihydropyridine and the like can be mentioned.

In the positive photosensitive resin composition of the present invention, it is essential to further use a phosphorus compound.
It has been found that the use of the polyamide represented by the general formula (I) is effective for discoloration and the like. Specific examples of the phosphorus-based compound that can be used in the present invention include diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate and tris (2,4-ditert- Butylphenyl) phosphite, bis [2,4-bis (1,1-dimethylethyl)
-6-methylphenyl] ethyl ester phosphorous acid, tetrakis (2,4-tert-butylphenyl) [1,1
-Biphenyl] -4,4'-diylbisphosphonite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite and the like. In addition, these can be used alone or in a mixture of two or more. Further, a general hindered phenol-based antioxidant can be used in combination.

The amount of the phosphorus compound to be added to the positive photosensitive resin composition is 0.5 to 20 parts by weight, preferably 1 to 10 parts by weight, per 100 parts by weight of the polyamide (A). When the amount is less than 0.5 part by weight, the effect of discoloration resistance cannot be obtained, and when the amount exceeds 20 parts by weight, sensitivity is lowered, and there is a problem in practicality.

If necessary, additives such as a leveling agent and a silane coupling agent can be added to the positive photosensitive resin composition of the present invention.

In the present invention, these components are dissolved in a solvent and used in the form of a varnish. Examples of the solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-
Dimethylacetamide, dimethylsulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene Glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate, methyl-3-methoxypropionate, etc., may be used alone or as a mixture.

In the method of using the positive photosensitive resin composition of the present invention, the composition is first applied to a suitable support, for example, a silicon wafer, a ceramic substrate, an aluminum substrate or the like.
Examples of the coating method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, and roll coating. Next, after pre-baking at 60 to 130 ° C. to dry the coating film, a desired pattern shape is irradiated with actinic radiation. As the actinic radiation, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used, but those having a wavelength of 200 to 500 nm are preferable. Next, a relief pattern is obtained by dissolving and removing the irradiated portion with a developer. Examples of the developer include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, and di-n. Secondary amines such as propylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine,
An aqueous solution of an alkali such as a quaternary ammonium salt such as tetramethylammonium hydroxide or tetraethylammonium hydroxide, and an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as alcohol such as methanol or ethanol or a surfactant. Can be suitably used. As a developing method, a system such as spray, paddle, immersion, and ultrasonic wave can be used. Next, the relief pattern formed by development is rinsed. As the rinse liquid,
Use distilled water. Next, heat treatment is performed to form an oxazole ring, and a final pattern having high heat resistance is obtained. The positive photosensitive resin composition according to the present invention is useful not only for semiconductor applications, but also as interlayer insulation for multilayer circuits, cover coats for flexible copper clad boards, solder resist films, liquid crystal alignment films, and the like. When used for a semiconductor device, a known method can be used.

[0028]

The present invention will be described below in detail with reference to examples. << Example 1 >> * Synthesis of polyamide 443.2 parts by weight of a dicarboxylic acid derivative obtained by reacting 1 mol of diphenyl ether-4,4'-dicarboxylic acid with 2 mol of 1-hydroxybenzotriazole (0.
9 mol) and 366.3 parts by weight (1.0 mol) of hexafluoro-2,2-bis (3-amino-4-hydroxyphenyl) propane were mixed with a thermometer, a stirrer, a raw material inlet, and a dry nitrogen gas inlet tube. Was placed in a four-necked separable flask, and 3000 parts by weight of N-methyl-2-pyrrolidone was added to dissolve. Thereafter, the reaction was carried out at 75 ° C. for 12 hours using an oil bath. Next, 5-norbornene-2,3-dissolved in 500 parts by weight of N-methyl-2-pyrrolidone
32.8 parts by weight (0.2 mol) of dicarboxylic anhydride was added, and the mixture was further stirred for 12 hours to complete the reaction. After filtering the reaction mixture, the reaction mixture was poured into a solution of water / methanol = 3/1, the precipitate was collected by filtration, washed sufficiently with water, and dried under vacuum to obtain the desired polyamide (A-1). Obtained.

* Preparation of Positive Photosensitive Resin Composition 100 parts by weight of the synthesized polyamide (A-1), 25 parts by weight of diazoquinone (B-1) having a structure of the following formula, and diethyl [[3,5-bis ( 1,1-dimethylethyl) -4
-Hydroxyphenyl] methyl] phosphonate (C-
1) 5 parts by weight was dissolved in 250 parts by weight of N-methyl 2-pyrrolidone, and then filtered through a 0.2 μm Teflon (registered trademark) filter to obtain a photosensitive resin composition.

* Evaluation of Developability After coating this positive photosensitive resin composition on a silicon wafer by using a spin coater, the composition was coated on a hot plate for 4 hours.
After drying for a minute, a coating film having a thickness of 5 μm was obtained. A g-line stepper exposure machine NSR-1503G3A (Nikon Corporation)
From 100 mJ / cm ² through reticle
After performing exposure by increasing by 0 mJ / cm ² , 2.3
After developing with an 8% aqueous solution of tetrahydroxyammonium hydroxide (manufactured by Tokyo Ohka Kogyo Co., Ltd .: NMD-3) for 40 seconds, the film was rinsed with pure water for 1 minute and air-dried with a spinner. As a result, a 5 μm line & space has an exposure amount of 25.
It was confirmed that the opening was at 0 mJ / cm ² .

* Evaluation of Colorability After applying this positive photosensitive resin composition to a quartz plate using a spin coater, the composition was heated at 120 ° C. on a hot plate for 4 hours.
Prebaked for minutes. Using a clean oven,
After heating and curing in a nitrogen atmosphere in the order of 30 minutes / 150 ° C. and 30 minutes / 320 ° C., a film having a thickness of 10 μm was obtained after curing. Next, when the transmittance at 500 nm was measured using a spectrophotometer, the transparency was as high as 52.1%. Next, after performing a heat treatment at 400 ° C. for 30 seconds using a hot plate, the transmittance at 500 nm was measured again with a spectrophotometer, and it was 29.8% and high transparency.

Example 2 Evaluation was made by replacing the phosphorus compound (C-1) in Example 1 with tris (2,4-ditert-butylphenyl) phosphite (C-2). << Example 3 >> The phosphorus compound (C-
Evaluation was performed by replacing 1) with bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid (C-3). << Example 4 >> The phosphorus compound (C-
The evaluation was performed with the addition amount of 1) being 1 part by weight. << Example 5 >> The phosphorus compound (C-
The evaluation was performed with the addition amount of 1) being 10 parts by weight. Example 6 In the synthesis of polyamide in Example 1, dicarboxylic acid obtained by reacting 0.8 mol of terephthalic acid and 0.2 mol of isophthalic acid instead of 1 mol of diphenyl ether-4,4′-dicarboxylic acid Polyamide (A-2) was synthesized using an acid derivative, and the other evaluations were the same as in Example 1. Example 7 In the synthesis of the polyamide in Example 1, 329.6 parts by weight of hexafluoro-2,2-bis (3-amino-4-hydroxyphenyl) propane was added.
9 mol), and 24.9 parts by weight (0.1 mol) of 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane were added instead. 3) was synthesized, and the other evaluations were performed in the same manner as in Example 1. << Example 8 >> The evaluation was performed by replacing the photosensitive diazoquinone compound (B-1) in Example 1 with (B-2).

Comparative Example 1 Evaluation was performed in Example 1 without adding a phosphorus compound. As a result, as shown in Table 1, the transmittance after curing and the transmittance after heat treatment were low. << Comparative Example 2 >> In Example 1, the phosphorus compound (C-
The evaluation was performed with the addition amount of 1) being 0.1 part by weight. As a result, the transmittance after curing and the transmittance after heat treatment were low. << Comparative Example 3 >> In Example 1, the phosphorus compound (C-
The evaluation was performed with the addition amount of 1) being 30 parts by weight. As a result, the sensitivity was lowered to 550 mJ / cm ² .

[0034]

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[0035]

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Table 1 shows the evaluation results of Examples 1 to 8 and Comparative Examples 1 to 3.

[Table 1]

[0037]

According to the present invention, it is possible to obtain a positive photosensitive resin composition in which the color of the cured film is light and the discoloration is small even in the heat treatment process after curing.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/037 G03F 7/037 7/075 521 7/075 521 H01L 21/027 H01L 21/30 502R F-term (Ref.) EC70 ED24 ED35 ED36 ED45 ED46 ED47 ED48 ED49 ED50 4J002 CL031 EQ016 EW047 EW067 EW117 GP03

Claims (6)

[Claims] 1. 100 parts by weight of a polyamide (A) represented by the general formula (I) and a photosensitive diazoquinone compound (B)
1 to 100 parts by weight and a phosphorus compound (C) 0.5 to 20
A positive photosensitive resin composition comprising parts by weight. Embedded image 2. The method of claim 1, wherein the phosphorus compound is diethyl [[3,5
-Bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, tris (2,4-ditert-butylphenyl) phosphite, bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid, tetrakis (2,4-tert-butylphenyl) [1,1-biphenyl] -4,4'-diylbisphosphonite, bis (2,4-di- 2. The composition according to claim 1, which is selected from tert-butylphenyl) pentaerythritol diphosphite.
The positive photosensitive resin composition according to the above. 3. X in a polyamide of the general formula (I)
Is selected from the following: The positive photosensitive resin composition according to claim 1 or 2, wherein Embedded image 4. Y in the polyamide of the general formula (I)
Is selected from the following: The positive photosensitive resin composition according to claim 1, 2 or 3. Embedded image 5. The positive photosensitive resin composition according to claim 1, wherein the photosensitive diazoquinone compound (B) is selected from the following. Embedded image 6. A semiconductor device manufactured using the positive photosensitive resin composition according to claim 1.