JPH01319528A - Epoxy resin composition for semiconductor encapsulation - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an epoxy resin composition for semiconductor encapsulation,
More specifically, the present invention relates to an epoxy resin composition for semiconductor encapsulation IJ, which has heat resistance, moisture resistance, and cold impact resistance, and which contains a specific curing agent.

[Conventional technology]

Generally, in semiconductor devices such as ICs and LSIs, resin encapsulation methods are widely used in which semiconductor elements are encapsulated with silicone resin, epoxy resin, etc. Among these encapsulation resins, In particular, epoxy resin is effective and good at maintaining airtightness after encapsulation, and is relatively inexpensive, making it a popular resin for encapsulating semiconductor devices. It is commonly used.

[Problem to be solved by the invention]

However, in this type of resin-sealed package, I
With the diversification of mounting methods for semiconductor devices such as C and LSI, the packages themselves tend to become smaller and thinner. In the case of resin-sealed packages, the epoxy resin used as the sealing resin itself does not have sufficient heat resistance; for example, if it is dipped into molten solder after being mounted on a board, the sealing resin may crack. Another problem is that the device characteristics may vary, and in terms of reliability, it is completely unsuitable for devices installed in automobiles, which require heat resistance of 150° C. or higher.

It is known that the heat resistance, moisture resistance, and cold shock resistance of cured epoxy resins used as sealing resins vary greatly depending on the epoxy resin skeleton, number of functional groups, etc. The development of heat-resistant epoxy resins is actively underway. For example, Japanese Patent Publication No. 62-53528 discloses an epoxy resin composition having a rigid biphenol structure in its skeleton. Since phenol novolac resin is used as the curing agent, the glass transition temperature of the cured product is 18
The temperature is about 0°C, and the heat resistance is not so excellent.

This invention was made to solve these conventional problems, and its purpose is to provide excellent heat resistance, moisture resistance, and cold shock resistance. An object of the present invention is to provide an epoxy resin composition of this type for semiconductor encapsulation.

[Means to solve the problem]

In order to achieve the above-mentioned objective 11, the epoxy resin composition for semiconductor pair 1L according to the present invention contains a bisimide phenol compound as a curing agent in the epoxy resin composition, thereby increasing the glass transition temperature of the sealing resin. It also has improved heat resistance and strength so that it does not damage the package or affect device characteristics even after thermal shock cycles.

That is, the present invention provides a bisimidophenol compound represented by -4 organic groups selected from the following formula:

An epoxy resin composition for semiconductor encapsulation characterized by containing an epoxy resin and an inorganic filler.

[For production]

Therefore, in this invention, since the epoxy resin composition contains a bisimide phenol compound as a curing agent, it is possible to increase the glass transition temperature of the sealing resin and improve the heat resistance strength. Even after a thermal shock cycle, there is no risk of damaging the package or affecting device characteristics.

〔Example〕

Hereinafter, the epoxy resin composition for semiconductor encapsulation according to the present invention will be explained in detail.

The epoxy resin composition for semiconductor encapsulation according to the present invention is -
A bisimidophenol compound represented by a tetravalent organic group selected from the following formula:

It contains an epoxy resin and an inorganic filler.

The bisimidophenol compound used in this invention is
It is obtained by condensing aminophenol and a tetracarboxylic dianhydride represented by the formula - in a phenolic solvent.

Therefore, the tetracarboxylic dianhydride is biphenyltetracarboxylic dianhydride.

Examples include pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, and the like.

In this condensation, 2 moles of amine phenol are reacted with 1 mole of tetracarboxylic dianhydride. At this time, the amount of aminophenol is 2
It can be used within the range of ~2.2 moles, but if the amount of aminophenol is less than 2 moles per mole of tetracarboxylic dianhydride, the acid will remain in the reaction product, resulting in poor heat resistance and moisture resistance. On the other hand, if the amount of aminophenol exceeds 22 moles, side reactions occur, which also adversely affects heat resistance and moisture resistance.

As the phenolic solvent, o-, p-, m-cresol, p-chlorophenol, a mixture thereof, etc. can be used, and the concentration of aminophenol and tetracarboxylic dianhydride is 5 to 30% by weight. The reaction is carried out within the range of 10 to 20% by weight, preferably within the range of 10 to 20% by weight, and the reaction temperature at this time is desirably within the range of 20 to 200°C. The bisimidophenol compound thus obtained is used alone or mixed with other curing agents.

Further, as the epoxy resin used in the present invention, various types of epoxy resins can be mentioned, such as novolak epoxy resin, bisphenol A epoxy resin, and alicyclic epoxy resin. Among these, Novolac-based epoxy resins are preferred because they have excellent high-temperature properties, and as for the epoxy resins, they may be used alone or two or more of them may be used in combination.

If necessary, epoxy resins such as brominated novolac epoxy resins and brominated bisphenol A epoxy resins may be used in combination with these epoxy resins, and in this case, the amount of these epoxy resins used is It is preferable that the epoxy resin used in combination is 50 parts by weight or less per 100 parts by weight of the epoxy resin.

Further, the blending ratio of the curing agent such as the bisimidophenol compound and the epoxy resin is preferably such that the OH equivalent of the bisimidephenol compound is 0.7 to 1.2 per equivalent of the epoxy group of the epoxy resin. If the OH equivalent of the bisimidophenol compound is less than 0.7 with respect to 1 equivalent of the epoxy group of the epoxy resin, the glass transition temperature of the composition will become low and the heat resistance will decrease, and on the contrary, the OH equivalent will decrease. If it exceeds 1.2, the bisimidophenol compound remains as an unreacted product in the cured product, resulting in a decrease in heat resistance and moisture resistance.

Furthermore, examples of the inorganic filler used in the present invention include crystalline silica powder, fused silica powder, alumina powder, talc, quartz glass powder, calcium carbonate powder, and glass fiber. The amount of these inorganic fillers added is preferably about 50 to 80% in the composition, and if the amount added is less than 50%, the effect of lowering the coefficient of linear expansion and curing shrinkage is reduced. If the amount becomes small and the amount added exceeds 80%, fluidity tends to deteriorate and workability tends to decrease. It is preferable to appropriately select and use the blending amount.

Furthermore, the epoxy resin composition for semiconductor encapsulation according to the present invention may optionally contain a curing accelerator such as an imitazole compound, a tertiary amine, a phosphorus compound, a coloring agent such as carphone black, and carnauba wax. , mold release agents such as synthetic wax, flame retardants such as antimony trioxide, γ-
A coupling agent such as glyciloxypropyltrimethoxysilane, a rubber component such as silicone rubber, fluororubber, etc. may be added to each of them in an amount that does not exceed 10% in the composition.

The epoxy resin composition for semiconductor encapsulation according to the present invention can be mixed using known mixing devices such as rollers, kneader mixers, extruders, and Henschel mixers (manufactured by Mitsui Miike Manufacturing Co., Ltd.). ) etc. can be easily prepared.

Next, examples of the epoxy resin composition for semiconductor encapsulation according to the present invention will be described in detail together with comparative examples thereof.

(Manufacturing Examples 1 to 5) The raw materials for waste were recrystallized according to the formulations and compositions shown in Table 1 below, dried under reduced pressure, and used for the synthesis of a hisimide phenol compound.

The synthesis of N,N-bis(p-hydroxyphenol)biphenylte]-carboxylic diimide begins with 1f! , 21 Put 500 g of m-cresol, 10 g of xylene, and 32.7 g of recrystallized and vacuum-dried p-amine phenol into a flask.
Biphenyltetracarboxylic acid 2 was uniformly dissolved at 20 to 30°C under a nitrogen stream, recrystallized and dried under reduced pressure.
Gradually add 44.1g of anhydride and keep at 20-30℃ for 2h.
r Stir 2 to react.

Gradually increase the darkness to 120 to 150°C at 10ml and reflux, remove the reaction product water by azeotroping with xylene at 1hr, and then
Ihr reactions were carried out at 200°C and 200°C. The amount of produced water is 5. : ] 99g theoretical amount 5.40. tH
)Met.

After that, approximately 1 m-cresol was removed by vacuum distillation, and the mixture was reprecipitated into 3.5 Il of methyl alcohol, filtered, washed with methyl alcohol, and then washed with 20 to 3 ml of methyl alcohol.
Drying under reduced pressure was performed at 0° C. for 8 hours to obtain a synthetic reaction product.

In the infrared absorption spectrum, the compound obtained in this way has an absorption based on the OH group at 3300 cm-' and an absorption at 17 cm-'.
Imide group C at 20cm-' and 1.780cm-'
A characteristic absorption based on the =O group was obtained, which confirmed that the product was the desired product.Production Example 1).

In addition, instead of the biphenyltetracarboxylic dianhydride, pyromellitic dianhydride (Production Example 2), benzophenonetetracarboxylic dianhydride (Production Example 3), cyclopentanetetracarboxylic dianhydride (Production Example 4) and butanetetracarboxylic dianhydride (Production Example 5) were used to obtain synthetic reaction products in the same manner as in Production Example 1. By identifying each of these compounds using the same method, we were able to confirm that each of them was the desired product.

(Examples 1 to 10. Comparative Examples 1 to 3.) A hisimide phenol compound and an epoxy resin or a phenol novolac resin were heated with a heated roll at 70 to 90°C for 15 minutes with the composition and blending ratio shown in Table 2 below. ~
20m1n, further], 10-15m at 30-150℃
A preliminary mixture was obtained by kneading 1n.

And these premixes, epoxy resin.

The phenol novolac resin, inorganic filler, curing accelerator, and other components were prepared to have the composition and combination shown in Table 3 below, and kneaded for 4 to 7 minutes using hot rolls at 70 to 100°C. Using a press machine, it was molded into a tablet with a diameter of 45 mm and a height of 35 mm so that its bulk density was 1.5 to 1.7.

Next, using the tab I knot obtained in this way, the mold temperature was 180℃±5℃, and the plunger pressure was 80kg.
/cm', and the molding time was 90 sec to make various reliability evaluation monitor chips and various evaluation test pieces, and each reliability evaluation monitor chip and each evaluation test piece. (The TFI test piece was subjected to post-curing treatment at 175°C for 8 hours.

In addition, using each evaluation test piece treated as described above, the bending elastic modulus 2 bending strength and linear expansion coefficient were measured.

The glass transition temperature and fluidity were each measured. The results are shown in Table 4 below.

Furthermore, using each of the reliability evaluation monitor chips treated as described above, a heat resistance reliability test, a moisture resistance reliability test, and a cold shock resistance test were conducted by the following means. The results are shown in Table 5 below.

゛Heat Resistance Reliability Test'' The time until failure occurs in the monitor chip was measured in air at 250°C.

“Moisture resistance reliability test” PCT (Pressure Cooker Te5t
) 1000hrJ at 1.30℃ and 2.7atm
The evaluation was based on the number of defective monitor chips in 1.

``Cold thermal shock resistance test'' - 30 m1n at 65℃ and 30m1n at 150℃ 1
The evaluation was made based on the number of defective monitor chips after 500 cycles.

That is, as can be seen from Table 4 above, when the epoxy resin composition for semiconductor encapsulation in this example is used, the basic properties such as the flexural modulus of elasticity 5 flexural strength and linear expansion coefficient of the device itself , the glass transition temperature of the composition can be raised without significantly changing its fluidity, etc., and as can be seen from Table 5 above, the device itself has excellent heat resistance, moisture resistance, and cold shock resistance. It has the following characteristics.

[Effects of the Invention] As described in detail below, according to the epoxy resin composition for semiconductor encapsulation according to the present invention, the epoxy resin composition contains
Since it contains a bisimidophenol compound as a hardening agent, it is possible to increase the glass transition temperature of the sealing resin and improve its heat resistance strength. , there is no risk of damaging the package or affecting the device characteristics, and it exhibits excellent heat resistance, moisture resistance, and cold shock resistance, and is used as a sealant for semiconductors such as ICs and LSIs. It has the advantage that it can be suitably used as a.

Agent Masao Dai Iwa

Claims (1)

[Claims] General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the above formula, R is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc. ▼ A tetravalent organic group selected from among those shown by] It is characterized by containing a bisimidophenol compound shown by, an epoxy resin, and an inorganic filler. An epoxy resin composition for semiconductor encapsulation.