JPH0229421A - Epoxy resin molding material for sealing - Google Patents

Abstract

PURPOSE:To form an epoxy resin molding material for sealing having a low stress and excellent in both the resistance to heat cycle for a long period of time and complex moisture resistance by incorporating a silicone rubber which has been subjected to surface treatment with a specific treating agent and an epoxy modified polybutadiene as the constituents of the molding material. CONSTITUTION:The title material is formed by incorporating a silicone rubber which has been subjected to surface treatment with an alkoxysilane and/or a polyether-modified silicone oil and an epoxy-modified polybutadiene each in an amount of 0.1-5wt.% to the whole molding material. As the alkoxysilane, a polyether-modified silicone oil and an epoxy-modified polybutadiene, common commercially available products, can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an epoxy resin molding material for encapsulation used for resin encapsulation of electronic/electrical parts, particularly various semiconductor elements.

[Conventional technology]

2. Description of the Related Art In order to physically and chemically protect semiconductor elements such as transistors, ICs, and LSIs and to facilitate mounting, resin encapsulation by low-pressure one-transfer molding or the like has been widely used. Epoxy resin is mainly used as the encapsulating resin due to its cost and reliability (moisture resistance), but in recent years the demand for semiconductor devices has increased with T4, high density, and miniaturization of vano gauges. In response to trends such as thinning, -
Layer-level properties are required.

Specifically, as wiring becomes finer and chip sizes become larger, reducing the stress of sealing resins is becoming more important today! Ti
Until now, silicones (various silicone compounds, modified silicone compounds, etc.) have been added to epoxy resin as a modifier for low stress (・1).
Therefore, attempts have been made to impart jiJl', 4 properties to the same resin molding abrasive to reduce its elasticity and alleviate internal stress (Special I9) 1986-133223.
)Refer to the official bulletin).

[Problem to be solved by the invention]

However, although the above-mentioned improvement measures have certainly improved in terms of reducing stress, further study has revealed that the long-term heat cycle resistance is still insufficient.
It became clear that problems such as package cracks and aluminum wiring sliding had occurred.

In addition, there remains the problem of adhesion between the resin and the base material, that is, moisture resistance. For this moisture resistance, composite moisture resistance including pre-treatment such as soldering is particularly important, but if the adhesion between the resin and the base material is not sufficient, solder immersion will cause 1. The gaps at the interface between the knobs and parts widen, allowing water to enter through them and significantly reducing moisture resistance.

In view of the above circumstances, it is an object of the present invention to provide an epoxy resin molding material for sealing that has low stress, long-term heat 1-cycle resistance, and excellent composite moisture resistance. Take it as a challenge.

[Failure to solve the problem]

In order to solve the above problems, the epoxy resin molding material for sealing according to the present invention contains silicone rubber surface-treated with alkoxysilane 11 and/or polyether-modified silicone oil and epoxy-modified polybutadiene in the total amount of the molding material. The content should be 0.1 to 5% by weight, respectively.

[For production]

By cleaning the surface treatment agent and modifier (modifying agent),
The wettability (compatibility) of silicone rubber or polybutadiene with other components is improved, and the molding material, which is a mixture of various components, becomes homogeneous throughout. By combining surface-treated silicone rubber and modified polybutadiene in such a homogeneous state, the elastic modulus of the epoxy resin decreases and internal stress is reduced2, thereby preventing cranking caused by internal stress over a long period of time. can be suppressed. At the same time, the adhesion of the resin to the substrate is greatly improved, and a high degree of moisture resistance can be obtained.

The blending amounts of the surface-treated silicone rubber and epoxy-modified polybutadiene are -ζ0. [If it is less than 5% by weight, the effect of the present invention will not be sufficiently obtained, and if it exceeds 5ffi (1%), the flowability of the molding + A material and the strength and appearance of the molded product will deteriorate.

〔Example〕

Examples of the epoxy resin in this invention include bisphenol A epoxy resin, bisphenol F epoxy resin, novola, 7-type epoxy resin, brominated epoxy resin, alicyclic epoxy resin, and heterocyclic epoxy resin. , there are no particular limitations. These may be used alone or in combination.

[Q] of the curing agent is also not particularly limited; for example, common materials such as intercalated amines, imidazoles, acid anhydrides, phenol novolac resins, and polyamide resins may be used alone or in combination of multiple types. Can be used. Also,
There is no limit to the amount used, and the necessary q may be set appropriately.

Alkoxysilanes used as surface treatment agents for silicone rubber are silane coupling agents containing one or more alkoxy groups in their molecules. 5iRs are often used. These include vinylsilane,
They are called epoxysilane, aminosilane, mercaptosilane, etc. More specifically, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ
-glycidoxypropyltrimethoxysilane, T-methacryloxypropyltrimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane.

Examples include γ-aminopropyltriethoxysilane, r-anilinopropyltrimethoxysilane, T-mercaptopropyl-1-oxysilane, and T-mercaptopropylmethyldimethoxysilane. However, the present invention is not limited to these, and for example, methyl l-ethoxysilane, methyltrimethoxysilane, etc. that do not contain the substituent in the organic functional group X can also be used. For the above, any commercially available products used for boat fishing can be used alone or in combination.

The amount of the alkoxysilane used during surface treatment is not particularly limited, but it is preferably about 0.1 to 10 parts per 100 parts by weight of silicone rubber (hereinafter referred to as 1 part). If the amount of the surface treatment agent is too small, a sufficient treatment effect may not be obtained, whereas if it is too large, surface bleeding or the like may occur in the molded product.

Similarly, polyether-modified silicone oil, which is used as a surface treatment agent for silicone rubber, is a silicone oil modified with polyethers, that is, a copolymer of silicone and polyether. Multiple types can be used together, and there are no particular limitations. The amount of the modified silicone oil used during surface treatment is the same as that for the alkoxysilanes described above.

The above two surface treating agents for silicone rubber are preferably used in combination because the treatment effect will be even higher, but each may be used alone.

The surface treatment method is not particularly limited, but for example, a method may be adopted in which the above-mentioned surface treatment agent is added to the silicone rubber which is being stirred at high speed using a mixer or the like and the mixture is stirred. At this time, the silicone rubber J. generates heat during treatment and reaches a high temperature, but when taken out after treatment, the surface temperature is 60 to 7.
It is preferable to perform this after cooling to about 0'c (if the temperature remains high, there is a risk of secondary agglomeration).

In addition, silicone rubber and surface treatment agent are simply mixed and stirred.
It is sufficient to just do this, but it is also preferable to take measures such as heating if necessary.

Next, epoxy-modified polybutadiene will be explained.

This is a polycitadiene modified to contain an epoxy group in the unat;a or side chain. For example, a commercially available polybutadiene modified with epoxy at both ends and inside can be used. In addition, when cleaving the epoxy resin molded resin, it is preferable to melt the epoxy-modified polybutadiene with any epoxy resin (mixing (pretreatment)) and react the two in advance.

In addition to the above-mentioned components of epoxy resin, curing agent 2, surface-treated silicone rubber, and epoxy-modified polybutadiene, the epoxy resin molding agent for sealing according to the present invention may be added as necessary. tertiary amines, imidazoles, organic phosphorus compounds; phosphines, etc.), fillers or reinforcing materials (glass fiber, carbon fiber, asbestos, talc, fused silica, calcium silicate, magnesium silicate, etc.), flame retardant agent (antimony trioxide, brominated epoxy resin, etc.), camping agent (silane coupling agent, etc.), mold release agent (wax, stearic acid salt, etc.), coloring agent (carbon bra, etc.).

It may also contain other components such as pigments such as gold VS oxides, pigments such as gold VS oxides, etc. The blending amounts of surface-treated silicone rubber and epoxy-modified polybutadiene in the entire molding material, including all of these, are 0.1 as described above.
~5% by weight.

An epoxy resin composition as a molding material can be obtained by mixing the above components in a mixer, blender, etc., and kneading them using a kneader, rolls, etc. After kneading, the mixture may be cooled and solidified, and pulverized into granules, if necessary. Molding is preferably carried out by (low-pressure) transfer molding or injection molding, but is not limited thereto; for example, casting, compression molding, etc. may also be performed.

Next, examples of the present invention will be described together with comparative examples.

Examples 1-5. Ratio / Calendar 1.2 = ■ ゛ Silicone rubber (TOμ Silicone 01) with an average particle size of 10 μm was stirred at high speed in a Henzel mixer for 1 l: While stirring, alkoxy Epoxysilane as a silane (Nippon Unicar (1)
3 parts of mercaptosilane (Chisso (S-810 manufactured by 1 Kiku)), 3 parts of mercaptosilane (S-810 manufactured by Chisso (1 Kiku),
749) were added together in a spray state (particle size: 5 μm). The surface temperature at the time of taking out the silicone rubber after the left side treatment was 60°C.

■ Polybutadiene modified with epoxy at both ends (A: Idemitsu Petrochemical (
Structure R45EI)T) 130~ by adding 20 parts
The mixture was melt-mixed at 150"C for 1 to 2 hours, then cooled and pulverized to obtain a pretreated modified polybutadiene A product.

■ Bo1butadiene B 41 Instead of both terminal epoxy-modified polybutadiene A, internal epoxy-modified polybutadiene (B; manufactured by Idemitsu Petrochemical @11
A pretreated product of modified polybutadiene B was obtained in the same manner as in Section 2, except that 45 UPI) was used.

■ Epoxy 4 Epoxy resin (made by Sumitomo Chemical @; softening point 68”c) 1
35 parts, brominated epoxy resin (same as above (manufactured by ■), 15 parts, phenol novolak resin (manufactured by Arayo Kagaku Kogyo (1), softening point 85°C) 75 parts, antimony trioxide 20 parts, fused silica 743 parts, carbon bra・3 parts of Tsuku, 4 parts of coupling agent (Nihon Uniriki = (Taru-187, ^-186 or Toray Silicone (+1) 511-6040),
3 parts carnauba wax and 2 parts triphenylphosphine
(total of 1,000 parts), the above 0-0 surface-treated silicone rubber and epoxy-modified polybutadiene A, B shown in Table 1 are treated with 1); 1 treated product (however,
The table shows the amounts of modified polybutadiene A and B), mixed in a mixer and then kneaded using a kneader to form an epoxy resin molding material. In addition, comparative example 1
In Comparative Example 2, the modified butadiene was not added, and in Comparative Example 2, the same untreated silicone rubber was used.

Using the above molding material, a 6-pin DIP, 3.2 mm length x 11.5 mm width pellet was made, and -
A heat shock of 65° C./1 minute to 150° C./1 minute was applied, and the aluminum wiring slide was measured after 1000 cycles.

(1fi511μ2 Using the above molding material, 18pin SOP, length 3゜2x
A beret with 2.3 horizontal fins was made and heated to 85°C and 85%.
After absorbing moisture for 72 hours under RH, it was floated on a molten solder bath at 260°C for 10 seconds, and finally a pressure Knoka test (PCT; 151°C, ■00% RH) was performed to reduce the percentage of 10% of the sealed product. The time required for a defect to occur was measured.

The above results are also shown in Table 1.

The molded products of the Examples containing both the surface-treated silicone rubber and the epoxy-modified polybutadiene exhibited good appearance, and as shown in Table 1, compared to the Comparative Examples, they exhibited better performance in the heat cycle test. Aluminum wiring slide is reduced to 1/2 or less, and composite moisture resistance is 2~2
This is an improvement of more than three times.

[Effect of the invention] The epoxy 4AJ resin molding material for sealing according to this invention has the following properties:
Compared to conventional products, it has low stress and long-term heat cycle resistance, preventing cracks and misalignment of aluminum wiring.
Moreover, it is possible to provide a good molded product with a composite moisture resistance of 1'11 degrees. Therefore, the epoxy resin molding + A material is expected to be used in a wide range of applications as a monopoly molding material used for resin encapsulation of various semiconductor devices.

Agent Patent Attorney Takehiko Matsumoto ``46tne 111 official text: (0悄0 November 11, 1985 [1 11 Rain 1163 special so-called t9E's l 80768 No. 2
, name of invention sealed 11. Jl] Epoxy resin molding material 3, relationship with the case of the person making the amendment (1 name, representative name 4, agent)

Claims (1)

[Claims] 1. An epoxy resin molding material for sealing containing silicone rubber surface-treated with alkoxysilanes and/or polyether-modified silicone oil and epoxy-modified polybutadiene, each in an amount of 0.1 to 5% by weight based on the total amount of the molding material. .