JPS6143620A - Sealing resin composition - Google Patents

Abstract

PURPOSE:A coating insulating composition, containing an epoxy resin, novolak type phenolic resin, zircoaluminate based inorganic polymer and a specific amount of an inorganic filler, having improved moisture and heat resistance, mechanical characteristics and moldability, and useful for sealing and coating electronic and electrical parts. CONSTITUTION:A sealing resin composition containing (A) an epoxy resin (containing >=2 or more epoxy groups in the molecule), (B) a novolak type phenolic resin, (C) a zircoaluminate based inorganic polymer containing one or more Zr and one or more Al in the molecule, preferably containing groups expressed by the formula and (D) 25-90wt% inorganic filler, preferably silica or alumina, as essential components. Preferably, the molar ratio (a/b) of the epoxy groups (a) in the component (A) to the phenolic OH groups in the component (B) is 0.1-10, and the amount of the component (C) is 0.01-20pts.wt. based on 100pts.wt. component (D).

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a resin composition for encapsulating semiconductor devices, etc., and particularly a highly reliable encapsulating resin composition with excellent moisture resistance and mechanical properties. Regarding.

[Technical Background of the Invention and Problems Therewith] Conventionally, electronic components such as diodes, transistors, and integrated circuits have been sealed using a resin encapsulation method using a thermosetting resin. This resin sealing method is economically advantageous compared to hermetic sealing methods using glass, metal, or ceramic, and is therefore widely put into practical use. Thermosetting resins are used as the sealing resin, and epoxy resin compositions are most commonly used in terms of reliability and cost. In epoxy resin compositions, various curing agents such as acid anhydrides, aromatic amines, novolac type phenolic resins, etc. are used. Among these, epoxy resin compositions using novolak type phenolic resin as a curing agent have superior moldability and moisture resistance compared to those using Ike's curing agent.
Since it is non-toxic and inexpensive, it is widely used as a semiconductor encapsulation material.

However, as recent semiconductor devices tend to be larger and more dense, if they are encapsulated with an epoxy resin composition using conventional novolac type phenolic resin as a hardening agent and subjected to a hot/cold cycle test, There is a problem in that the bonding wire opens, the sealing resin cracks, or the pellet cracks, which impedes the function of the electronic component and reduces reliability. Furthermore, even when a moisture resistance test was conducted, the same phenomenon as in the hot/cold cycle test occurred, which was a big problem.

[Object of the Invention] The object of the present invention was to solve the above problems, and to provide a highly reliable sealing resin composition with excellent moisture resistance, mechanical properties, and moldability. It is something to do.

[Summary of the Invention] As a result of extensive research to achieve the above object, the present inventors have discovered that a resin composition using a zircoaluminate-based polymer as a coupling agent for an inorganic filler has excellent moisture resistance. It has been found that the resin composition has good properties and other properties and is suitable as a resin composition for sealing.

That is, the present invention provides (A) an epoxy resin, (B) a novolac type phenolic resin, (C) a zircoaluminate-based inorganic polymer containing at least one zirconium atom and one or more aluminum atoms in the molecule, and ( D) An inorganic filler is an essential component, the inorganic filler is 25 to 90% by weight based on the resin composition, and the zircoaluminate inorganic polymer is 0% to 100 mm part of the inorganic filler.
．． 01 to 20 parts by weight of the sealing resin composition.

As long as the epoxy resin used in the present invention (A> is a compound having at least two or more epoxy groups in its molecule, there are no particular restrictions on its molecular structure, molecular weight, etc., and therefore all commonly used epoxy resins can be mentioned. It will be done.

Specific examples include aromatic resins such as bisphenol type, alicyclic resins such as cyclohexane derivatives, and epoxy resins such as epoxy novolak resins represented by the following general formula.

(In the formula, R1 represents a hydrogen atom, a halogen atom, or an alkyl group, R2 represents a hydrogen atom or an alkyl group, and n represents an integer of 1 or more.) These epoxy resins may be one or two types.
More than one species can be mixed and used.

The (B) novolac type phenolic resin used in the present invention includes novolac type phenol resins obtained by reacting phenols such as phenol and alkylphenols with formaldehyde or paraformaldehyde, and modified resins thereof, such as epoxidized or butylated novolac types. Examples include phenol resin. The blending ratio of the novolak type phenolic resin is determined by the molar ratio of the epoxy group <a of the (A) epoxy resin and the phenolic hydroxyl group (b) of the novolak type phenol resin (B) [
(a)/(b)] is preferably within the range of 0.1 to 10. If the molar ratio is less than 0.1 or more than 10, the moisture resistance, molding workability, and electrical properties of the cured product will deteriorate, and either case is unfavorable. Therefore, it is limited within the above range.

The zircoaluminate inorganic polymer (C) used in the present invention is not particularly limited as long as it contains a group containing at least one zirconium atom and one or more aluminum atoms in its molecule. do not have.

The blending ratio of the zircoaluminate-based polymer is preferably within the range of 0.01 to 20 parts by weight per 100 weight of the inorganic filler. Its blending amount is 0.01
If it is less than 20 parts by weight, there is no effect on moisture resistance, and if it exceeds 20 parts by weight, molding workability is reduced, and either case is not preferable. Therefore, it is preferable to limit it within the above range.

Inorganic fillers (D) used in the present invention include silica powder, alumina, antimony trioxide, talc, calcium carbonate, titanium white, clay, asbestos, mica,
Examples include red iron fiber, glass fiber, carbon fiber, etc., and one or more of these, iON&LT [i#Jg
h!・Z h'3 (7) 5'5 anal:
Silica powder and alumina are preferred and effective. The blending ratio of the inorganic filler is 25 to 25% of the resin composition.
It needs to be 90% by weight.

If the amount is less than 25% by weight, moisture resistance, mechanical properties,
It has no effect on moldability, and if it exceeds 90% by weight, it becomes bulky and has poor moldability, making it unsuitable for practical use.

The sealing resin composition of the present invention contains an epoxy resin, a novolac type phenolic resin, a zircoaluminate-based inorganic polymer, and an inorganic filler as essential components. Mold release agents such as metal salts, acid amides, esters, and paraffins, flame retardants such as chlorinated paraffin, bromotoluene, hexabromobenzene, and antimony trioxide, and colorants such as carbon black and red iron are added as appropriate. May be blended.

The general method for using the encapsulating resin composition of the present invention as a molding material is to uniformly mix an inorganic filler and a zircoaluminate-based inorganic polymer in a high-speed fluid mixer, and then mix the epoxy resin and novolac-type phenol. After selecting the resin and other raw materials in a predetermined composition ratio and mixing them sufficiently uniformly using a mixer, etc., the resin and other raw materials are further melted and mixed using heated rolls or mixed using a kneader, etc., and then cooled and solidified to an appropriate size. It can be crushed and used as a molding material.

[Effects of the Invention] The encapsulating resin composition of the present invention has excellent moisture resistance, mechanical properties, and heat resistance, and has good molding f'f:I properties and is highly reliable. - When used for sealing electrical parts, coating insulation, etc., it can provide excellent characteristics and sufficient reliability.

[Examples of the Invention] The present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples.

In the following Examples and Comparative Examples, "r%" means "wt%".

Example 1% of zircoaluminate polymer was added to 69% of silica powder, mixed for 15 minutes with a high-speed fluid mixer, and then cresol novolac epoxy resin (epoxy resin) was added to 69% of silica powder.
Fi 215) 18% and novolac type phenol resin (phenol fi 107) 10% were added and mixed at room temperature, and thoroughly kneaded with rolls at 90 to 95°C to obtain a resin composition. After cooling, this was crushed to obtain a molding material. The obtained molding material was made into a tablet, injected into a mold that had been preheated and heated to 170° C. by transfer molding, and cured to give a molded product.

This molded article was tested for moisture resistance, mechanical properties, etc., and the results are shown in Table 1.

Comparative example Cresol novolac epoxy resin (epoxy equivalent: 21
5) To 20%, 10% of novolac type phenol resin (phenol weight: 107) and 70% of silica powder were blended, and a resin composition and a molding material were obtained in the same manner as in the examples to obtain a molded article. This molded article was tested for shelf life in the same manner as in the Examples, and the results are shown in Table 1.

Table 1 = 11 2 on the bottom of the 30X25X5111R1 molded product
Embed a 5x25x3 copper plate, -40℃ and +200℃
C. for 30 minutes each, and resin cracks were investigated after 15 cycles were repeated.

*2 An electrical component having two aluminum wirings was tested using the sealing resin composition, and the time required for 50% disconnection (defect occurrence) due to aluminum corrosion was evaluated.

Claims (1)

[Scope of Claims] 1 (A) an epoxy resin, (B) a novolac type phenolic resin, (C) a zircoaluminate-based inorganic polymer containing at least one zirconium atom and one or more aluminum atoms in the molecule; and (D) a sealing resin composition comprising an inorganic filler as an essential component, the inorganic filler being 25 to 90% by weight based on the resin composition. 2 Molar ratio of the epoxy group (a) of the epoxy resin and the phenolic hydroxyl group (b) of the novolac type phenolic resin [
(a)/(b)] is 0.1 to 10, the sealing resin composition according to claim 1 or 2, wherein 3. The sealing resin composition according to claim 1, wherein the zircoaluminate inorganic polymer is blended in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the inorganic filler.