JP2001042518A - Positive photosensitive resin composition and semiconductor device using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive photosensitive resin composition capable of forming a pattern high in resolution and film endurance and small in the warp of a wafer after hardening the resin and to provide the semiconductor device formed by using it. SOLUTION: The positive photosensitive resin composition comprises 100 pts.wt. of polyamide (A) represented by the formula and 1-100 pts.wt. of a photosensitive diazoquinone compound (B), or 100 pts.wt. of the polyamide (A) and 1-100 pts.wt. of the photosensitive diazoquinone compound (B) and 1-30 pts.wt. of a phenol compound (C), and the semiconductor device is formed by using this.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-stress positive photosensitive resin which can obtain a pattern with a high resolution and a high residual film ratio, and has a small warp of a substrate such as a wafer after curing. The present invention relates to a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, a polyimide resin having excellent heat resistance and excellent electrical and mechanical properties has been used for 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 integration, enlargement, thinning and miniaturization of the sealing resin package, transition to surface mounting by solder reflow, etc. It is becoming needed.

On the other hand, a technique for imparting photosensitivity to the polyimide resin itself has recently attracted attention. For example, the following formula (6) is given as a photosensitive polyimide resin.

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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 such that the unexposed portion of the diazoquinone compound is insoluble in the alkaline aqueous solution, and the exposure causes the diazoquinone compound to undergo a chemical change and become soluble in the alkaline aqueous solution. By utilizing the difference in solubility between the exposed part and the unexposed part, a coating film pattern can be formed only in the unexposed part.

When these photosensitive resins are actually used in products, the adhesion between the photosensitive resin and the sealing resin becomes important. Since these are mainly used for interlayer insulation and serve as a permanent protective film and exist between the circuit element and the sealing resin, if the adhesion between the photosensitive resin and the sealing resin is poor, they are separated at the interface. Occurs, which causes a problem of lack of practicality.

In recent years, in particular, the size of wafers has increased, and
00 mm wafers have been used. In a large wafer, since the linear expansion coefficient of the Si wafer is different from that of the photosensitive resin, the wafer is warped, and a problem has arisen that the wafer is broken in a back surface grinding process for thinly grinding the wafer. Therefore, development of a low-stress photosensitive resin in which the linear expansion coefficient of the photosensitive resin is close to that of a silicon wafer has been desired.

[0007]

SUMMARY OF THE INVENTION A positive photosensitive resin which can obtain a pattern with a high resolution and a high residual film ratio and has a small warp of a wafer after the resin is cured. Further, a semiconductor device using the same is obtained.

[0008]

According to the present invention, there is provided a compound represented by the general formula (1):
And a photosensitive diazoquinone compound (B) in an amount of 1 to 100 parts by weight. (In the formula (1), X is selected from the following formula (2), and Y is selected from the following formula (3).)

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Embedded image Further, the polyamide (A) 100 represented by the general formula (1)
Parts by weight, 1 to 100 parts by weight of a photosensitive diazoquinone compound (B) and 1 to 30 parts by weight of a phenol compound (C) represented by the general formula (4) and / or (5). It is.

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In a further preferred embodiment, the photosensitive diazoquinone compound (B) is selected from the following:

Embedded image The polyamide (A) is a positive photosensitive resin composition in which Y is selected from the following and has a linear expansion coefficient after curing of 5 to 45 ppm.

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Further, using the above-mentioned positive photosensitive resin composition, the positive photosensitive resin composition is coated by heating and curing so as to have a thickness of 0.1 to 30 μm. This is a semiconductor device including a semiconductor element obtained by heating.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The polyamide of the formula (1) comprises a bisaminophenol having the structure of X and a dicarboxylic acid having the structure of Y.
When heated at 0 ° C., the ring closes and changes to a heat-resistant resin called polybenzoxazole.

X of the polyamide (1) of the present invention is, for example,

Embedded image It is.

Among them, 3-diamino- is particularly preferred as a film having a low coefficient of linear expansion and low stress after curing.
4,4-dihydroxybiphenyl is exemplified. This structure has a structure in which the resin structure after curing has linearity, and the coefficient of linear expansion of the cured film is small and close to the coefficient of linear expansion of the silicon wafer, so that the warpage of the wafer is reduced.

The linear expansion coefficient of the cured resin is 5 to 45 pp.
m is preferred. It is difficult to make the linear expansion coefficient of the cured resin less than 5 ppm. If the linear expansion coefficient of the cured resin exceeds 45 ppm, the substrate such as a wafer will be warped. Further, in order to increase the solubility in an organic solvent, it is possible to copolymerize another diaminodihydroxy compound to such an extent that the coefficient of linear expansion does not increase.

[0015] Y of the polyamide (1) of the present invention is, for example,

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

Among them, those having a low linear expansion coefficient and a low stress property especially after curing of the film.

Embedded image It is.

Further, Z in the formula (1) is, for example,

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

Z in the formula (1) is used, for example, when adhesion is particularly required to a substrate such as a silicon wafer, and the use ratio b can be up to 40 mol%. . If it exceeds 40 mol%, the solubility of the resin is extremely reduced, scum is generated, and pattern processing cannot be performed. When using X, Y, 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, 21
No. 3,669,658.

For example, the following are mentioned.

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Among these, the following are particularly preferable from the viewpoint of a high residual film ratio.

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The compounding amount of the photosensitive diazidoquinone compound (B) to the polyamide (A) is 1 to 100 parts by weight with respect to 100 parts by weight of the polyamide. If the compounding amount is less than 1 part by weight, the patterning property of the resin is poor. Conversely, if it exceeds 100 parts by weight, the tensile elongation of the film is significantly reduced.

A dihydroxypyridine derivative can be added to the positive photosensitive resin composition of the present invention, if necessary, to enhance the photosensitive characteristics. As the dihydroxypyridine derivative, 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-carbomethoxy-
1,4-dihydropyridine and the like can be mentioned.

In the positive photosensitive resin composition of the present invention, the sensitivity can be improved by further containing a phenol compound represented by the general formulas (4) and (5).

[0025]

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[0026]

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As a technique for adding a phenol compound to a positive resist composition, for example, Japanese Patent Application Laid-Open No. 3-2002
No. 51, JP-A-3-200252, JP-A-3-20052
JP-A-200253, JP-A-3-200254, JP-A-4-1650, JP-A-4-1651, JP-A-4-11260, JP-A-4-123
No. 56, JP-A-4-12357. However, phenol compounds such as those described above have a small effect of improving sensitivity even when used in a positive photosensitive resin containing a polyamide as a base resin in the present invention.

However, the general formula (4) in the present invention,
When the phenol compound represented by (5) is used, the dissolution rate in the exposed area increases, and the sensitivity improves. Further, the film loss in the unexposed portion as seen when the sensitivity is increased by reducing the molecular weight is very small. Further, in the present invention, as a new property by adding the phenol compounds represented by the general formulas (4) and (5), a positive photosensitive resin composition having improved adhesion to a sealing resin can be obtained. I found that.

Examples of the compound represented by the general formula (4) include, but are not limited to, the following.

[0030]

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[0031]

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[0032]

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Examples of the compound represented by the general formula (5) include, but are not limited to, the following.

[0034]

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[0035]

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[0036]

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Among these, particularly preferred in terms of sensitivity and residual film ratio are:

Embedded image It is. The compound represented by the general formula (4) or (5) is contained alone or in the form of a mixture in the total phenol compound (C) in an amount of 50% by weight or more.

The addition amount of the phenol compound (C) is preferably 1 to 50 parts by weight based on 100 parts by weight of the polyamide (A). If the added amount is less than 1 part by weight, the effect of improving sensitivity cannot be obtained, and if the added amount exceeds 50 parts by weight, the decrease in the residual film ratio becomes large, or precipitation occurs during frozen storage, resulting in lack of 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 and the like may be used alone or in combination.

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, ceramic, 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 120 ° 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;
Secondary amines such as diethylamine and di-n-propylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like An aqueous solution of an alkali such as a quaternary ammonium salt or an aqueous solution obtained by adding a suitable amount of a water-soluble organic solvent such as alcohol such as methanol or ethanol or a surfactant thereto 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. Distilled water is used as the rinsing liquid.
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 comprises:
It is useful not only for semiconductors but also for interlayer insulation of multilayer circuits, cover coats of flexible copper clad boards, solder resist films, liquid crystal alignment films, and the like. In particular, when the positive photosensitive resin composition of the present invention for a semiconductor element is used, a semiconductor element excellent in productivity and quality can be obtained. A known method can be used for manufacturing a semiconductor element and a semiconductor device.

[0044]

The present invention will be described below in detail with reference to examples. Example 1 * Synthesis of polyamide 0.86 mol of terephthalic acid, 0.14 mol of isophthalic acid and 1-hydroxy-1,2,3-benzotriazole 2
Dicarboxylic acid derivative 38 obtained by reacting
0.4 g (0.95 mol) of 3,3-diamino-4,4
216.3 g (1.0 mol) of dihydroxybiphenyl
Was placed in a four-neck separable flask equipped with a thermometer, a stirrer material inlet, and a dry nitrogen gas inlet tube, and stirred for 12 hours to complete the reaction. After the reaction mixture was filtered, the reaction mixture was poured into a solution of water / methanol = 3/1, the precipitate was collected by filtration, washed sufficiently with water, dried under vacuum, and expressed by the desired general formula (1). X was a mixture of the following formulas X-1 and Y was a mixture of the following formulas Y-1 and Y-2 to obtain a polyamide (A-1) consisting of a = 100 and b = 0.

* Preparation of Positive Photosensitive Resin Composition 100 g of the synthesized polyamide (A-1), 25 parts by weight of diazoquinone (Q-1) having the structure of the following formula, and 200 parts by weight of N-methyl-2-pyrrolidone After dissolution, 0.2
Filtration through a μm Teflon filter gave a photosensitive resin composition.

* Characteristic evaluation After coating this positive photosensitive resin composition on a silicon wafer using a spin coater, it was dried on a hot plate at 120 ° C. for 4 minutes to obtain a coating film having a thickness of about 5 μm. . G-line stepper exposure machine NSR-1505G3A
50 mJ / c through a reticle by Nikon Corporation
from m ² 20mJ / cm ² increase at a time to 540mJ / cm
Exposure was performed up to ² . Next, the exposed portion was dissolved and removed by immersion in a 1.4% tetramethylammonium hydroxide aqueous solution for 60 seconds, and then rinsed with pure water for 30 seconds. As a result, it was confirmed that the pattern was formed. Remaining film ratio at this time (film thickness after development / film thickness before development)
Showed a very high value of 87.6%. Further, in the remaining pattern, fine pattern peeling was not observed at all, and it was confirmed that the adhesion at the time of development was excellent.

Separately, the positive photosensitive resin composition was similarly applied to a 6-inch silicon wafer (thickness: 625 μm) so as to have a thickness of 10 μm after curing, prebaked, and then used in a clean oven made by Koyo Lindberg for 30 minutes. /
The resin was heated and cured in the order of 150 ° C., 30 minutes / 250 ° C., 30 minutes / 350 ° C., and further at a nitrogen concentration of about 1 to 2%. Next, the warpage of this wafer was measured by a surface roughness meter, and as a result, it was 10 μm. In addition, the linear expansion of the cured film
Was measured by Since the cured film had a small coefficient of linear expansion and was close to a silicon wafer, the stress applied to the wafer was small and the warpage of the wafer was small.

Example 2 In the synthesis of the polyamide in Example 1, a dicarboxylic acid derivative obtained by reacting terephthalic acid or isophthalic acid with 2 mol of 1-hydroxy-1,2,3-benzotriazole was used. 1 mole of diphenyl ether-4,4'-dicarboxylic acid and 1 mole of
Dicarboxylic acid derivative 443.2 obtained by reacting 2 mol of -hydroxy-1,2,3-benzotriazole
g (0.9 mol), represented by the general formula (1)
Synthesizes a polyamide (A-2) having the following formula Y-3 and a = 100 and b = 0, further using a diazoquinone (Q-2) having the following formula structure as a diazoquinone, And the other evaluations were the same as in Example 1.

Example 3 In the synthesis of the polyamide in Example 1, the amount was reduced to (0.95 mol), and instead of 1,3-bis (3-aminopropyl) -1,1,3,3
12.4 parts by weight of tetramethyldisiloxane (0.05
Mol), and X is represented by the following formula X-
1, Y is a mixture of the following formulas Y-1 and Y-2, and Z is a formula Z
-1, a polyamide consisting of a = 95 and b = 5 (A-
3) was synthesized, and the other evaluations were performed in the same manner as in Example 1.

Example 4 A phenol compound (P-1) having a structure represented by the following formula was added to the resin composition in Example 1.
15 parts by weight were added, and the other evaluations were performed in the same manner as in Example 1.

Example 5 A phenol compound (P-2) having a structure represented by the following formula was added to the resin composition in Example 1.
15 parts by weight were added, and the other evaluations were performed in the same manner as in Example 1.

Example 6 The same evaluation as in Example 1 was performed except that the diazoquinone compound in Example 1 was changed to the following formula Q-2.

Example 7 (No data for Example 7 in Table 1) The same evaluation as in Example 1 was conducted except that the amount of the phenol compound (P-1) in Example 1 was changed to 5 parts by weight. went.

Comparative Example 1 In Example 2, hexafluoro-2,2-bis (3-amino-4-hydroxyphenyl) propane was reacted instead of 3,3-diamino-4,4-dihydroxybiphenyl. X represented by the general formula (1), Y is Y-3, and
= 100, polyamide (A-2) consisting of b = 0,
Otherwise, the same evaluation as in Example 1 was performed. << Comparative Example 2 >> The same evaluation as in Example 1 was performed except that the amount of the phenol compound added in Example 1 was increased to 60 parts by weight.

[0055]

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[0056]

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[0057]

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[0058]

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The resin components of Examples 1 to 7 and Comparative Examples 1 and 2,
Table 1 summarizes the evaluation results.

[Table 1]

[0060]

According to the present invention, it is possible to provide a positive photosensitive resin capable of obtaining a pattern having a high resolution and a high residual film ratio and having a small warpage of a wafer after curing the resin, and a semiconductor device using the same. be able to.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08L 77/06 C08L 77/06 G03F 7/004 501 G03F 7/004 501 7/037 501 7/037 501 7/40 501 7/40 501 H01L 21/027 H01L 21/312 D 21/312 21/30 502R F term (reference) 2H025 AA00 AB16 AC01 AD03 BE01 CB26 FA03 FA17 FA29 2H096 AA25 BA10 BA20 EA02 GA08 HA01 JA04 4J001 DA01 DB04 DC10 DC14 DC16 EB35 EB36 EB37 EB55 EB56 EC23 EC38 EC65 EC74 ED46 FB03 FC06 GB13 GD07 GD08 JA07 4J002 CL061 CL071 EJ037 EJ057 EJ067 EQ016 FD206 GP03 GQ05 5F058 AA02 AC07 AF04 AG01 AH01 AH02

Claims (6)

[Claims] 1. 100 parts by weight of a polyamide (A) represented by the general formula (1) and a photosensitive diazoquinone compound (B)
A positive photosensitive composition comprising 1 to 100 parts by weight. (In the formula (1), X is selected from the following formula (2), and Y is selected from the following formula (3).) Embedded image Embedded image 2. 100 parts by weight of a polyamide (A) represented by the general formula (1) and a photosensitive diazoquinone compound (B)
A positive photosensitive composition comprising 1 to 100 parts by weight and 1 to 30 parts by weight of a phenol compound (C) represented by formulas (4) and / or (5). Embedded image Embedded image 3. The method according to claim 1, wherein the photosensitive diazoquinone compound (B) is
3. The positive photosensitive resin composition according to claim 1, which is selected from the following. Embedded image 4. The positive photosensitive resin composition according to claim 1, wherein Y in the polyamide (A) is selected from the following. Embedded image 5. The positive photosensitive resin composition according to claim 1, wherein the linear expansion coefficient after curing is 5 to 45 ppm. 6. The positive photosensitive resin composition according to claim 1, which has a thickness of 0.1 to 3 after being heated and cured.
0 μm, pre-bake, exposure, development,
A semiconductor device comprising a semiconductor element obtained by heating.