JPH0229420A - Epoxy resin molding material for sealing - Google Patents

Abstract

PURPOSE:To form an epoxy resin molding material for sealing having a low stress and an excellent resistance to heat cycle for a long period of time by incorporating a silicone rubber, which has been subjected to surface treatment with a specific treating agent, in a specified amount as a constituent component 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, in an amount of 0.1-5wt.% to the whole molding material. Preferably, the silicone rubber is one having an average particle diameter of 1-20mum. As the alkoxysilane and the polyether-modified silicone oil, common commercially available products can be used, and the amount of each of them to be used is of the order of 0.1-10pts.wt. for 100pts.wt. of the silicone rubber.

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]

1- In order to physically and chemically protect semiconductor elements such as transistors, TCs, and LSIs, and to facilitate mounting, resin encapsulation by low-pressure transfer molding or the like has been widely practiced. Epoxy resin is mainly used as the sealing resin due to its cost and reliability (moisture resistance). In response to trends such as thinner products, advanced properties are required.

Specifically, as wiring becomes finer and chip sizes become larger, reducing stress in sealing resins has become an important issue today, and until now, modifiers have been used as modifiers to provide low stress. By adding silicones (various silicone compounds, modified silicone compounds, etc.) to epoxy resin, we can impart riJtQ properties to the resin molding material and reduce its elasticity.
Attempts have been made to alleviate internal stress (Patent Application 1986)
(Refer to Publication No.-133223).

[Problem to be solved by the invention]

However, although the above-mentioned improvement measures have certainly improved in terms of reducing stress, 1. After further investigation, we found that long-term heat cycle resistance was still insufficient.
It became clear that problems such as package cracks and aluminum wiring sliding had occurred.

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

[Means to solve the problem]

In order to solve the above problems, the epoxy resin molding material for sealing of the present invention contains silicone rubber surface-treated with alkoxysilanes and/or polyether-modified silicone oil in an amount of 0.1 to 5% by weight based on the total amount of the molding material. %
Include.

[For production]

The action of the surface treatment agent improves the wettability (compatibility) between the silicone rubber and other components, and the molding material, which is a mixture of various components, becomes homogeneous throughout. By blending surface-treated silicone rubber in such a homogeneous state,
The elastic modulus of the epoxy resin decreases, internal stress is relaxed and reduced, and the occurrence of cracks caused by internal stress can be suppressed in the long term.

If the amount of the surface-treated silicone rubber blended is less than 0.1% by weight based on the total amount of the molding material, the effects of the present invention will not be sufficiently obtained, and if it exceeds 5% by weight,
The flowability of the molding material and the strength and appearance of the molded product are reduced.

〔Example〕

Examples of the epoxy resin in this invention include bisphenol A-based epoxy resins, bisphenol A-based epoxy resins, novolac-type epoxy resins, brominated epoxy resins, alicyclic epoxy resins, and heterocyclic epoxy resins, with particular limitations. Not allowed. These alone are
Alternatively, multiple types can be used together.

The type of curing agent is not particularly limited; for example, common curing agents such as various amines, imidazoles, acid anhydrides, phenol novolamc resin, polyamide resin, etc. may be used singly or in combination of multiple types. Can be used. Also,
There is no limit to the amount used, and the required amount may be set as appropriate.

The silicone rubber is not particularly limited, but its average particle size is preferably 1 to 20 μm, and 1 μm.
If it is less than 20 μm, there is a risk of secondary agglomeration, and if it exceeds 20 μm, there is a tendency for surface bleeding to occur in the molded product.

Alkoxysilanes as surface treatment agents for silicone rubber are silane coupling agents containing an alkoxy group of 1 (11i1 or more) in the molecule, and (1) an alkoxy group R ( as a hydrolyzable group that reacts with inorganic materials). (methoxy group, ethoxy group, etc.), ■ any organic functional group These include vinylsilane, vinylsilane,
They are called epoxysilane, aminosilane, mercaptosilane, etc. More specifically, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-
Glycidoxypropyltrimethoxysilane, T-methacryloxypropyltrimethoxysilane, r-(2-aminoconidel)aminoprobilt T-aminopropyltriethoxysilane, T-anilinopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane Examples include methoxysilane and γ-mercaptopropylmethyldimethoxysilane. However, the invention is not limited to these, and includes, for example, methyltrimethoxysilane, which does not contain a substituent in the organic functional group X,
Methyltriethoxysilane and the like can also be used. As mentioned above, - You can use any commercially available products used for boat fishing in China, Germany, or a combination of several types.

The amount of the alkoxysilanes used during surface treatment is 4
), but is not limited to 100 parts of silicone rubber (
0. It is preferable to use about 1 to IO parts. If there is too little surface treatment agent,
If a sufficient treatment effect is not obtained and, on the other hand, the amount is too high, surface bleeding or the like may occur in the molded product.

Polyether-modified silicone oil as a surface treatment agent for silicone rubber is a silicone oil modified with polyethers, that is, a copolymer of silicone and polyether. Alternatively, multiple types can be used together without any particular limitation. The amount of the modified silicone oil used during surface treatment is the same as that for the alkoxysilanes described above.

It is preferable that the above-mentioned two surface treating agents for silicone rubber are 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 and stirred into the silicone rubber which is being stirred at high speed using a mixer or the like. At this time, silicone rubber generates heat during processing and becomes high temperature, but it is preferable to take it out after processing after cooling the surface temperature to about 60 to 70 °C (if it remains at high temperature, secondary (There is a risk of agglomeration). Although the silicone rubber and the surface treatment agent may be simply mixed or stirred, it is also preferable to take measures such as heating if necessary.

In addition to the above-mentioned components of the epoxy resin, curing agent, and surface-treated silicone rubber, the epoxy resin molding material for sealing according to the present invention may optionally contain a hardening accelerator (tertiary hardening agent).
grade amines, imidazoles, Iff IJ compounds;
(bosfins, etc.), filling ('' or reinforcement (A (glass fiber, carbon fiber, asbestos, slag, fused silica, etc.)
Calcium silicate.

Magnesium silicate, etc.), ff1lt retardant (antimony trioxide, brominated epoxy resin, etc.), coupling agent (silane coupling agent, etc.), mold release agent (wax, stearic acid, stearate, etc.), coloring agent (pigments such as carbon oxide) may also be included. The blending amount of the surface-treated silicone rubber in the entire molding material, including all of these, is 0.1 to 5% by weight, as described above.

An epoxy resin composition as a molding material can be obtained by mixing the above components using, for example, a mixer, a blender, or the like, and kneading them using a kneader, roll, or the like. After kneading, if necessary, the mixture may be cooled to solidify and pulverized into granules. 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 to 5. Comparative Example 1.2 ■ While silicone rubber A (manufactured by TO-μ Silicone Rubber) with an average particle size of 10 μm was being stirred at high speed in a Hentzel mixer, alkoxysilanes were added to 100 parts of the same silicone rubber. Epoxy silane (A-18 manufactured by Nippon Unicar) as
7) 3 parts and further 5 parts of polyether-modified silicone oil (5ll-3749 manufactured by TOMU Silicone ■) were added together in a spray state (particle size 50μ) and stirred to obtain surface-treated silicone rubber A. . The surface temperature when the silicone rubber was taken out after treatment was 60 to 70'C.

■ The same as ■ above except that 3 parts of the same epoxysilane and 3 parts of mercaptosilane (manufactured by Chisso ■η 5-810) were used as the Δ-cleavage alkoxysilanes. Surface treatment was performed in the same manner, and surface treated silicone rubber B was prepared using i! It was.

■ Human blood odor L≧≦6U4ffl As alkoxysilane flame 1, 3 parts of aminosilane (Japan 1 Nika 01) or -1100) was used, but the surface treatment was carried out in the same manner as in ① above, and the surface Processed silicone JC? Ta.

■ -” Epoxy 1 Epoxy resin (manufactured by Sumitomo Chemical Co., Ltd. (+@; softening point 68”C)
) 135 parts, 15 parts of brominated epoxy resin (made by ■ above),
Phenol novolac resin (manufactured by Arayo Kagaku Kogyo (1); softening point 85"c) 75 parts, antimony trioxide 20 parts, melt 1
Mj 743 parts of silica, 3 parts of carbon black, coupling agent (ll-187 manufactured by Nippon Unicar Gη) 4'fll
+, 3 parts of carnauba wax and 2 parts of l-rifenylphosphine (total of 1000 parts above) were blended with the above ■C■ surface-treated silicone rubbers Δ to C in the amounts shown in Table 1, and mixed in a mixer. The mixture was then kneaded using a kneader to obtain an epoxy resin molding material. In Comparative Example 1, the same untreated silicone rubber was used.

Using the above molding material, 60 pin QF P, length 11
x horizontal 1: (■■, Make a pellet of ``fl-2,4ms'' and heat it at -65°C/1 minute at -150°C/
A 1-minute heat shock was applied, and the pano-dicrasok number was measured after 1000 cycles.

(A) Two and one high ζ-Sakemi Wani 22 (-Ra! Goenid-Using the above molding material, 16pin I)
A pellet of IP, 113°2×11.5 m in width was prepared, and a heat shock of 65° C/1 minute to +150° C/1 minute was applied thereto, and the aluminum wiring slide was measured after 500 cycles.

The following results are also shown in Table 1.

The molded products of the Examples containing surface-treated silicone rubber all had a good appearance, and as shown in Table 1, the package cracking characteristics were more than three times improved compared to those of the Comparative Examples. Moreover, the aluminum wiring slide in the P1-cycle test was reduced to 1/2 or less.

In addition, ]7-A silicone rubber with an average particle size of 5 μm and a weight of 15 to 20 μm was subjected to a surface treatment similar to that of a paperback, and molded products were similarly produced using the same, and its properties were evaluated. As a result, it was found that rT had the same performance as the above embodiment.

(Effects of the Invention) The epoxy resin molding material for sealing according to the present invention has low stress and excellent heat cycle resistance over a long period of time compared to conventional ones, and has good properties that suppress the occurrence of cracks, cracks, and misalignment of aluminum wiring. Therefore, the epoxy resin molding material is expected to have a wide range of uses, such as a molding material used for resin encapsulation of various semiconductor elements.

Agent Patent Attorney Takehikoen Matsumoto ``45 Yami Ne Ichimasa's spontaneous petition 1, Indication of the case 1988 Patent Application No. 180766 2, Name of the invention Epoxy resin molding material for sealing 3, ?Iti correction person Relationship to the case Patent applicant address 1048 Oaza Kadoma, Kadoma City, Osaka Name (583) Matsushita Electric Works Co., Ltd. Representative Director Toshio Miyoshi 4, no agent 6, subject of amendment > j + 11 As per FIC 6 , Specification Subject to Amendment 7, Contents of Amendment (2) The text "Transistor...required" on page 1, line 18 to page 2, line 6 of the specification is corrected to the following wording.

Item 1 [Semiconductor elements such as transistors, ICs, and LSIs are
In order to protect from external environment such as shock and vibration, to have good electrical insulation and heat dissipation properties, and to facilitate mounting,
Conventionally, resin sealing by low-pressure transfer molding or the like has been widely used. As the sealing resin, from the aspects of high productivity, cost reduction, and reliability (moisture resistance),
Epoxy resin is mainly used, but in recent years semiconductor devices have become more dense, denser, smaller in single package, and V#
In response to trends such as increased design, even higher reliability is required. ” ■ On page 2, lines 18-19 of the specification, the phrase “as a result of further consideration” has been corrected to the following.

Note: ``Recent demands for lower stress in encapsulating resins are increasing due to the miniaturization of wiring rules, larger pellet sizes, and diversification of package forms due to recent advances in the functionality of devices. Under the situation that has become more severe, "■" on page 8 of the specification, lines 8-10 [? ! Correct the phrase "reinforcing materials (...magnesium silicate, etc.)" to "reinforcing materials (glass fibers, carbon fibers, whiskers, fine ceramics, silica, etc.)" ■Page 8, No. 12 of the specification In line 13, the text "Release agent (stearate, etc.)" should be corrected to "Release agent (synthetic wax, natural wax, etc.)."

■ In two places in the specification, page 11, line 11 and lines 16-17 of the same page, the phrase "-65℃/1 minute - 1150℃/1 minute" has been replaced with "-65℃/15 minutes - 1150℃". ℃15 minutes”.

■ Table 1 on page 12 of the specification is corrected as shown in the attached sheet.

Claims (1)

[Scope of Claims] 1. An epoxy resin molding material for sealing containing 0.1 to 5% by weight of silicone rubber surface-treated with alkoxysilanes and/or polyether-modified silicone oil based on the total amount of the molding material. 2. The epoxy resin molding material for sealing according to claim 1, wherein the silicone rubber has an average particle size of 1 to 20 μm.