JPS6181425A - Epoxy resin composition for encapsulation, and semiconductor device using same - Google Patents

Abstract

PURPOSE:To provide the titled resin composition containing an epoxy resin, a specific hardener, and hydrated amorphous silicon dioxide, having high performance, and giving a resin-encapsulated semiconductor device having high reliability. CONSTITUTION:The objective composition contains (A) an epoxy resin (preferably novolac epoxy resin having an epoxy equivalent of preferably 170-300), (B) a curing agent having >=2 phenolic hydroxyl groups in one molecule (preferably novolac phenolic resin) and/or an acid anhydride curing agent (e.g. maleic anhydride, succinic anhydride, etc.) and (C) preferably 0.1-10wt% hydrated amorphous silicon dioxide. The composition is preferably further incorporated with fused silica and/or crystalline silica as an inorganic filler.

Description

Detailed description of the invention [Technical field to which the invention pertains] The present invention relates to a sealant epoxy resin composition and a resin-encapsulated semiconductor device using the same, and particularly relates to a highly reliable sealant epoxy resin composition and a resin-encapsulated semiconductor device using the same. The present invention relates to a highly reliable resin-sealed semiconductor device using the same.

TECHNICAL BACKGROUND OF THE INVENTION AND THE PROBLEMS] As a sealing technology for semiconductor elements such as ICs, L8Is, transistors, etc., hermetic seals using ceramics in metal are employed.

However, such hermetic seven-rules have economical problems such as a large number of parts and complicated processes. For this reason, recently, resin-sealed semiconductor devices, in which a semiconductor element is sealed with a resin molding body made of a thermosetting resin or the like, as shown in the drawings, have become mainstream. That is, 1 in the figure is a semiconductor element 0, and this semiconductor element l is mounted on the bed 2. A plurality of bonding wires 3 are connected to the electrode portion (pad portion) of the semiconductor element 1, and the other ends of these wires 3 are connected to a lead bin 4. Then, the semiconductor element 1. Ped 2. A portion of the wire 3 and the lead pin 4 are sealed with a resin sealing body 5.

However, resin-sealed semiconductor devices have the following drawbacks. That is, the bonding wire 3 connecting the semiconductor element 1 and the lead pin 4 is embedded in the resin molding body 5, and the bonding wire 3 is subjected to mechanical stress by the resin molding body 5.

Since the thermal expansion coefficients of the resin molded body 5 and the embedded components are different, if the resin molded semiconductor device is repeatedly exposed to high and low temperatures, it will no longer be able to withstand the stress due to the difference in the thermal expansion coefficients, and the bonding wire 3 had the disadvantage that it was easy to cause disconnection or poor contact.

[Object of the Invention] The object of the present invention is to improve the drawbacks of such a conventional epoxy resin composition for sealing and fC resin-encapsulated semiconductor devices using the same, and to provide a highly reliable epoxy resin composition for sealing. An object of the present invention is to provide an epoxy resin composition and a highly reliable resin-encapsulated semiconductor device using the same.

[Outline of the invention] In order to achieve the above object, as a result of extensive research by the present inventors, the following sealing piece epoxy resin composition and a resin-encapsulated semiconductor device using the same have been developed. It was discovered that it has superior characteristics compared to the conventional one.

That is, the epoxy resin composition for sealing of the present invention is (,)
An epoxy resin (b) a curing agent having at least two 7-enolic hydroxyl groups in one molecule or #i/an acid anhydride curing agent; and (c) a sealing material containing hydrated amorphous silicon dioxide. This is an epoxy resin composition for

Further, a resin-sealed semiconductor device of the present invention includes a semiconductor element and a resin-sealed body for sealing the semiconductor element, wherein the resin-sealed body is made of (-) epoxy resin. (b) C in one molecule; a curing agent or/and an acid anhydride curing agent having at least two phenolic hydroxyl groups; and (c) a cured product of an epoxy resin composition containing hydrated amorphous silicon dioxide. This is a characteristic resin-sealed semiconductor device.

The above-mentioned epoxy resin is commonly known and is not particularly limited. For example, glycidyl ether type epoxy resins such as bisphenol A type epoxy resin and phenol novolak type epoxy resin.

Glycidyl ester type epoxy resins, glycidylamine type EBOKI 7 resins, linear aliphatic epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, epoxy resins, etc. that have two or more epoxy groups in one molecule Examples include epoxy resins. However, these epoxy resins may be used alone or in a mixed system of two or more. More preferred epoxy resins are novolac type epoxy resins having a t/t of 170 to 300 per epoxy, such as primary phenol novolak type epoxy resins, cresol novolac type epoxy resins, halogenated phenol novolac type epoxy resins, and the like. These epoxy resins preferably have a chlorine ion content of 1099 m or less and a hydrolyzable chlorine content of 0.1% by weight or less. The reasons are 10
This is because if more than ppm of chlorine ions or more than 0.1 ppm of hydrolyzable chlorine is contained, the aluminum electrodes of the sealed semiconductor element are likely to be corroded.

The curing agent having two or more phenolic hydroxyl groups in one molecule, which is one of the curing agents mentioned above, includes phenol resins, polyoxystyrene, and polyhydric phenol compounds, and specific examples thereof include phenol novolac resins. , cresol novolac m fat, start-butylphenol novolak resin, novolak type phenol resin such as nonylphenol novolak resin, resol type phenol resin, polyoxystyrene such as polyparaoxystyrene, bisphenol A, etc., and halogenated products of these compounds. Among these, novolac type phenolic resin and polyoxystyrene are most preferred. These curing agents can be used alone or in a mixed system of two or more.

As the acid anhydride which is the other curing agent, any aliphatic, alicyclic or aromatic carboxylic anhydride or a substituted carboxylic anhydride thereof can be used. Examples of such acid anhydrides include maleic anhydride,
Succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrontalic anhydride, trimellitic anhydride,
Pyromellitic anhydride, nadic anhydride (3,6-nindomethylene-1.2.3.6-tetrahydrophthalic anhydride).

Methyl nadic anhydride, 3.3', 4.4'-benzophenone tetracarboxylic acid anhydride, tetrabrome anhydride 7
Examples include tarric acid, chlorendic acid anhydride, and one or more selected from the group consisting of these.

Each of the above curing agents may be used alone, or both may be used in an appropriate combination. The blending amount of the curing agent is such that the ratio of the total number of phenolic hydroxyl groups and/or anhydrous carboxyl groups to the number of epoxy groups in the epoxy resin is 0.5 to 1.
It is desirable to mix it so that it is within the range of 5. The reason for this is that outside the above range, the moisture resistance of the resulting epoxy resin composition tends to deteriorate.

The hydrated amorphous silicon dioxide used in the present invention will be explained. Methods for producing silicon dioxide include a so-called dry method in which it is produced in a gas phase and a so-called wet method in which it is produced in water. The hydrous amorphous silicon dioxide of the present invention is produced by a wet method. Silicon dioxide produced by a wet method has a larger number of silanol groups on the surface and a larger amount of adsorbed water than silicon dioxide produced by a dry method. Therefore, phosphorous silicon dioxide produced by a wet method is called hydrated amorphous silicon dioxide. Adsorbed water i- can be reduced by heat treatment at high temperature.

It is preferable that the adsorbed water content does not exceed FilO weight %, and more preferably does not exceed 3 weight %.

It is preferable that the hydrated amorphous silicon dioxide is blended into the epoxy resin composition in an amount of 0.1 to 10 parts by weight.

The epoxy resin composition according to the present invention may include, if necessary,
Various additives such as inorganic fillers and curing accelerators can be added.

Generally known inorganic photonic agents include fused silica (melted crystalline silica), crystalline silica, glass fiber, talc, alumina, calcium silicate, calcium carbonate, barium sulfate, magnesia, etc. Among these, fused silica and crystalline silica are most preferred because of their high purity and low thermal expansion.

When using other inorganic fillers, they are preferably used in combination with fused silica or crystalline silica.

The blend f of the inorganic filler is preferably about 1.5 to 4 times the total weight of the epoxy resin and curing agent.

Curing accelerators are useful for shortening curing time and improving the properties of cured products. Although commonly known curing accelerators can be used in the present invention, it is desirable to use an organic phosphine compound in order to obtain a highly reliable epoxy resin for sealing and a resin-encapsulated semiconductor device.

A tertiary phosphine compound s in which all R1-Re are organic groups A second phosphine compound in which only R8 is hydrogen %R1! There are primary phosphine compounds in which +R8 are both hydrogen. Specifically, triphenylphosphine, tributylphosphine, tricyclohexylphosphine, methyldiphenylphosphine, butylphenylphosphine,
These include diphenylphosphine, phenylphosphine, and octylphosphine. Further, R1 may be an organic group containing an organic phosphine. Examples include 1,2-bis(siphenylphosphino)ethane and bis(diphenylphosphino)methane. Among these, arylphosphine compounds are preferred, particularly triphenylphosphine, 1
．． Most preferred are 2-bis(diphenylphosphino)ethane, bis(diphenylphosphino)methane, and the like. These organic phosphites/compounds may be used alone or in a mixture of two or more. However, the composition ratio of the organic phosphine compound may generally be within the range of 0.01 to 20% by weight of the resin content (epoxy resin and curing agent), but particularly preferable properties are obtained when the composition ratio is within the range of 0.01 to 5% by weight. It will be done.

The epoxy resin composition for soil use of the present invention may further contain other additives, such as natural waxes, synthetic waxes, metal salts of straight chain fatty acids, acid amides, esters, or paraffins, as necessary. mold release agent, chlorinated paraffin,
Flame retardants such as bromotoluene, hexabromobenzene and antimony trioxide, colorants such as carbon black, silane coupling agents, etc. may be appropriately added and blended. The general method for producing V4 from the above-mentioned soil-use epoxy resin composition as a molding material is to thoroughly mix the raw material components selected at a predetermined composition ratio using, for example, a mixer.
Furthermore, an epoxy resin molding material can be easily obtained by melt-mixing using a hot roll or mixing using a kneader or the like.

The resin-sealed semiconductor device of the present invention can be easily manufactured by encapsulating the semiconductor device using the epoxy resin composition for sealing. The most common method of sealing is low-pressure transfer molding, injection molding, and compression molding.

Sealing by casting or the like is also possible. The epoxy resin composition is cured by heating during sealing, and a resin-sealed semiconductor device can finally be obtained by encapsulating the cured product of this composition. It is particularly desirable to heat to 150° C. or higher during curing.

[Examples of the invention Examples 1 to 6 Cresol novolak type epoxy resin (epoxy resin A) with epoxy equivalent weight of 220, brominated epoxy novolac resin (epoxy resin B) with epoxy equivalent weight of 290, molecular weight 8
00 phenol novolac fat curing agent, tetrahydrophthalic anhydride curing agent, hydrated amorphous silicon dioxide by wet process, amorphous silicon dioxide by dry process, fused silica powder, triphenylphosphine curing accelerator, antimony trioxide, carnauba wax , carbon black, and a silane coupling agent (r-glycidoxypropyltrimethoxysilane) were selected in the composition (parts by weight) shown in Table 1, and each composition was mixed with a mixer and kneaded with a heated roll. , 10 types of transfer molding materials including comparative examples were used by U! 4fB.

By performing transfer molding using the molding material thus obtained, the MOa type integrated circuit was sealed with resin. For sealing, molding material heated to 90℃ using a high-frequency preheater is heated to 170℃.
fc by molding at 180°C for 2 minutes and after-curing at 180°C for 4 hours.

Comparative Example 1f'i Poor fluidity and transfer molding was not possible. was prepared, and the resin-sealed semiconductor device was placed in a constant temperature bath at +20σC and left for 30 minutes. Thereafter, it was taken out and left at room temperature for 5 minutes, and then placed in a constant temperature bath at -65°C for 30 minutes. Thereafter, it was taken out and left at room temperature again for 5 minutes. The above operations are considered to be one cycle.

Continuously conduct thermal cycle tests. The cycle was interrupted at any time as the thermal cycle test progressed, and the characteristics of the resin-sealed semiconductor device were measured using a tester to investigate the occurrence of defects. The results are shown in Table 2.

Table 2 [Effects of the Invention] As is clear from the above objects of the present invention, summary description, and examples, the epoxy resin composition for sealing of the present invention has excellent performance, and it can be used for By encapsulating with

[Brief explanation of the drawing]

The drawing is a cross-sectional view of a resin-sealed semiconductor device. 1... Semiconductor element 2... Bed 3... Bonding wire 4... Rit bottle 5... Resin sealing body

Claims (1)

[Claims] 1. (a) an epoxy resin, (b) a curing agent or/and an acid anhydride curing agent having at least two phenolic hydroxyl groups in one molecule, and (c) hydrated amorphous silicon dioxide. An epoxy resin composition for sealing 2 characterized by comprising: an epoxy resin composition for sealing according to claim 1, wherein the epoxy resin is a novolac type epoxy resin having an epoxy equivalent of 170 to 300; The epoxy resin composition 4 for sealing according to claim 1, wherein the curing agent is a novolac type phenolic resin, the content of hydrated amorphous silicon dioxide in the epoxy resin composition is 0.1 to 10. % by weight of the epoxy resin composition 5 for sealing according to claim 1, and the epoxy resin composition according to claim 1, wherein the epoxy resin composition contains an organic phosphine compound as a curing accelerator. Epoxy resin composition 6 for sealing, the epoxy resin composition serving as an inorganic filler,
The epoxy resin composition 7 for sealing according to claim 1 containing fused silica and/or crystalline silica, a resin sealing type comprising a semiconductor element and a resin sealing body for sealing the semiconductor element. In the semiconductor device, the resin encapsulant comprises (a) an epoxy resin, (b) a curing agent or/and an acid anhydride curing agent having at least two phenolic hydroxyl groups in one molecule, and (c) a hydrated amorphous form. A semiconductor device 8 characterized in that it is a cured product of an epoxy resin composition containing silicon dioxide, and a semiconductor device according to claim 7, wherein the epoxy resin is a novolac type epoxy resin having an epoxy equivalent of 170 to 300. 9. The semiconductor device 10 according to claim 7, wherein the curing agent is a novolac type phenolic resin, and the epoxy resin composition has a content of hydrated amorphous silicon dioxide of 0.1 to 10% by weight. The semiconductor device 11 according to claim 7, the semiconductor device 12 according to claim 7, wherein the epoxy resin composition contains an organic phosphine compound as a curing accelerator, and the epoxy resin composition The semiconductor device according to claim 7, wherein the product contains fused silica and/or crystalline silica as an inorganic filler.