JPH01319529A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide the present composition of good moldability, improved in moisture resistance reliability, causing few package cracks after soldering dipping, comprising an epoxy resin, phenolic resin curing agent and each specific silicone oligomer and silane coupling agent. CONSTITUTION:The objective composition comprising (A) an epoxy resin (pref. of novolak type), (B) a phenolic resin curing agent, (C) a silicone oligomer of formula I (X is epoxy, mercapto, amino, ureide, hydroxyphenyl, carboxyl group-contg. alkyl or aryl; R<1>-R<6> are each methyl, ethyl or phenyl; n is 4-25), and (D) a silane coupling agent of formula II (Y is epoxy, mercapto, amino, diamino or ureide-contg. alkyl; R<7> is methyl, ethyl, methoxy or ethoxy; R<8> is methoxy or ethoxy) having such functional group that the group Y is reactive with the group X.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to the control of semiconductors, and in particular, despite the remarkable improvement in the degree of integration in recent years, there are demands for thinner and smaller sizes than ever before. The present invention relates to an epoxy resin composition suitable for inhibiting LSIs and the like.

(Prior art) In recent years, transfer molding using an epoxy resin composition has become the most widely used method for stabilizing conductors, engineering C, LEI engineering, etc. because it is inexpensive, mass-producible, well-balanced, and reliable. . However, as the degree of integration of semiconductors increases, there is also a strong demand for miniaturization of equipment that uses folds, so semiconductors, especially L
The pan cages for SI, etc. have changed from the conventional D-type P type to flat packages and PLOO (Plastic Leeded).
Surface-mount packages such as chip carriers are increasingly being adopted.

Furthermore, in recent years, demands for high-density packaging have become increasingly strong, and surface-mount packages are becoming larger in area and thinner, despite the need for larger areas for fixing.

As a result, reliability, especially the ability to maintain moisture resistance, has become a problem.

The use of surface mount type materials not only reduces the moisture resistance reliability after mounting, but also causes the worst problem of cracks in the package during mounting.

The above-mentioned deterioration in moisture resistance reliability and package cracks are caused by the following two causes. One is the thermal shock experienced during soldering during mounting. Surface mount type packages are mounted on boards using infrared solder reflow method, solder jet method (Wave solder ring), and VaporPha day solder using Takasu point solvent vapor.
This is done by using a ring, etc., but at this time, even in the case of t, the entire package is soldered at a temperature of 200 to 60
It undergoes a significant thermal shock, being rapidly heated to 0°C. Another cause is water absorption. When a package is left in a normal environment, it easily absorbs moisture, and during soldering, this moisture rapidly evaporates and expands, causing the package to swell and crack.

As these countermeasures, four improvements are being considered: reducing internal stress, improving high-temperature strength, reducing water absorption, and improving adhesion.

For example, in JP-A-61-183314, it has 2 to 20 consecutive silicon-enzyme bonds, at least two alkoxy groups or silanol groups, and at least one epoxy group or hydroxyl group. Silicon number is 2 to 5 and has one or more functional groups that can react with force.
It has been shown that the inclusion of zero silica compounds improves crack resistance.

JP-A-62-136860 discloses that water absorption can be reduced by modifying an epoxy resin or phenol resin with organopolysiloxane beforehand.

JP-A No. 62-192423 discloses an organoborisiloxane having one or more groups selected from vinyl groups, epoxy groups, amino groups, carboxyl groups, hydroxyl groups, and cyan groups in the molecule. It has been shown that soldering heat resistance improves when

In addition to the above, attempts are being made to lower the filler filling rate, water absorption rate, and the inclusion of diene-based synthetic resins. However, no concrete solution has been found yet (Reference: Nikkei Microdevice, May 1988 issue, pages 65-56).

(Problems to be Solved by the Invention) The present invention provides a stabilizing agent which prevents deterioration in moisture resistance and cracking of surface-mounted packages, which have been difficult to solve with conventional techniques, and which also has good moldability. It is something to do.

(Means for solving the problem) As a result of various horizontal analysis, Nagisa et al. solved the above problem by using an organosilicone compound with all the functional groups attached at both ends and a specific chain length instead of a pendant. They discovered that all of the above problems could be significantly improved by using a specific silane coupling agent in combination, and completed the present invention.

That is, the present invention comprises: (A) Epoxy resin CB) Phenol resin curing agent (C) Organosilicone compound represented by the following formula (D)
Among the silane coupling agents represented by the following formula, those in which Y has an L functional group capable of reacting with the above compound (Y-81+ R'')
2. An epoxy resin composition for semiconductor stabbing which has the above four components as main components, particularly preferably a silicone oligomer in which X is an alkyl group containing a specific functional group, and a specific one.
It is used in combination with a silane coupling agent containing all functional groups.

Any epoxy resin having two or more epoxy groups in one molecule can be used in the present invention. For example, bisphenol A-reduced epoxy resin, novolac type epoxy resin synthesized from various phenols, crycidyl ester type epoxy resin, glycidylamino type epoxy resin, chain aliphatic epoxy resin, alicyclic epoxy resin, ring-free type Epoxy resins or epoxy resins into which all halogens such as chlorine and bromine have been introduced may be used, and one or more of these may be used. Among these, novolac type epoxy resins are particularly preferred. The less ionic impurities and components that easily decompose into ions in these epoxy resins, the better. Specifically, free sodium ions,
Chloride ions are less than 5 ppm each and hydrolyzable -
・It is preferable that the content of Rodene be 500 ppm or less.

The phenolic resin curing agent used in the present invention includes 1
Those having at least two or more phenolic hydroxyl groups in the molecule are used. For example, phenol, resorcinol, furesol, xylenol, propylphenol, amylphenol, butylphenol, octylphenol, phenylphenol, allylphenol, bisphenol A, etc. are synthesized singly or in combination with novolak resin, polyisopropenylphenol, Examples include polyvinylphenols and phenol resin curing agents into which halogen groups are introduced, and one or more of these may be used. Among these, novolac resins containing uncondensed phenolic compounds of 1 M% or less, preferably 5% by weight or less are suitable.

The blending amount of the curing agent is such that the ratio of the phenolic hydroxyl group of the curing agent to the epoxy group of the epoxy resin is in the range of 0.5 to 1.5, preferably in the range of 0.7 to 1.2 for bamboo. . If it is outside the above range, it is not preferable because it lowers the moisture resistance reliability.

The silicone oligomer used in the present invention has the following general formula.

X in the above formula is an epoxy group, a mercapto group, an amine/group,'
an alkyl group or an aryl group containing a near L'ide group, a hydroxyphenyl group, a carboxyl group, and R1, R2, R3, R4, R5 and R6 are each a methyl, ethyl, or phenyl group, and di, n is 4 or more, 2
Indicates an integer less than or equal to 5.

It is necessary that X be a group that can react with an epoxy resin or a phenolic curing agent. Otherwise, the soldering heat resistance will not improve. Alternatively, it is necessary that it be present only at both ends of the molecule. This is because if the temperature is less than -1, the soldering heat resistance is poor.

n is preferably 20 or less, more preferably 16 or less, 4
That's all. If n is greater than 25, not only will the solder heat resistance be poor, but the solder will also seep onto the surface of the molded product, causing mold stains and poor marking.

The amount of this component added is 0.02 to 5% by weight based on the total composition. Less than 0.02% by weight has little effect;
If the amount exceeds % by weight, the effect will decrease.

The following silane coupling agents are essential to be used in combination with the above components.

In the above formula, Y is an alkyl group having an epoxy, mercapto, amino, diamino, or ureido group, and R7 is a methyl, ethyl, methoxy, or ethoxy group.
, R8 represents a methoxy or ethoxy group.

The amount added varies depending on the type and amount of the filler, but is generally 0.05 to 2% by weight based on the entire composition.

It is necessary that the functional group of Y of the silane coupling agent is capable of reacting with X of the silicone oligomer. As a specific example, (1) X of the silicone oligomer is an alkyl group containing a dE epoxy group, and Y of the silane coupling agent is
is an alkyl group having a mercapto group (2) X of the silicone oligomer is an alkyl group containing an epoxy group, and Y of the silane coupling agent is an alkyl group having an amino and/or ureido group (3) ) X of the silicone oligomer is an alkyl group containing an amino group or a ureido group, and Y of the silane camping agent is an alkyl group containing an epoxy group. (4) X of the silicone oligomer is an alkyl group containing a mercapto group. Yes, silane coupling agent (7)
Y is an alkyl group having an epoxy group (5) X of the silicone oligomer is an alkyl group containing a hydroxyphenyl group, and Y of the silane coupling agent is an alkyl group having an epoxy group (6) Silicone oligomer X is an alkyl group containing a carboxyl group, and Y of the silane coupling agent
is an alkyl group having an epoxy group.

Furthermore, in the case where the above coupling agent is used, a silane coupling agent having another functional group may be further used.

Next, the present 1JEIK uses a curing accelerator. -tn and other curing accelerators include 1,8-diazobicyclo (5,4゜0
)-7-undecene (hereinafter abbreviated as DBU), DBU
- DBU 9 conductors such as trimellitic acid (or anhydride) salts, DBU and 7-erul novolac salts, triorganophosphines such as tributylphosphine and triphenylphosphine, triethylammonium tetraphenylboron, tetraphenylphosphonium tetraphenyl Examples include boron salts such as boron, and @species imidazole derivatives, which may be used alone or in combination.

Inorganic fillers used in the present invention include powders of crystalline silica, fused silica, talc, alumina, calcium sulfate, calcium carbonate, barium carbonate, etc., or glass fibers, etc. The above is used. Among these, silica, especially fused silica, is preferred because of its high purity and low coefficient of thermal expansion. In addition to the usual pulverized products, spherical products can also be used.

The content of the filler is 68% by weight or more, preferably 70% by weight or more based on the total composition.

The epoxy resin composition of the present invention may contain mold release agents such as carnauba wax, montan wax, higher fatty acids and their calcium salts, fluorine compounds, and silicone oil, as well as non-rogenated epoxy resins and antimony trioxide. A flame retardant, a coloring agent such as carbon black, etc. can be appropriately added and blended.

Furthermore, it does not impede the epoxy resin composition of the present invention to incorporate a stiffening agent such as silicone rubber or butadiene rubber in order to reduce the stress on the object to be restrained. convenient for the purpose. It is also preferable to blend an imide compound such as maleimide in order to improve the heat resistance completely.

The epoxy resin composition of the present invention can be easily produced by sufficiently mixing raw materials in a predetermined composition ratio using a mixer, and then further melt-mixing using a roll, kneader, or the like.

(Example) All parts below in Examples 1 to 16 and Comparative Examples 1 to 8 refer to parts by weight.

85 parts of cresol novolak type epoxy resin with epoxy equivalent of 200, 10 parts of brominated phenol novolak type epoxy resin with epoxy equivalent of 270, 45 parts of phenol novolac resin (curing agent), triphenylposphine i, 5
m, 500 parts of fused silica 8 (111), 3 parts of carnauba wax, 1.5 parts of carbon blank, 10 parts of antimony trioxide, and 14 parts of silicone rubber powder (stress reducing agent) were kept constant. Xypropyltrimethoxysilane (silane coupling agent a), mercaptopropyltrimethoxysilane (silane coupling agent b), ureidoglobiltriethoxysilane (silane coupling agent c), aminopropyltrimethoxysilane (silane coupling agent The ratio of d) is the composition ratio shown in Table 2, and the silicone oligomer is R1 of the general formula.
-R6 are all methyl groups, and the part of The mixture was mixed, kneaded with a heated roll, and cooled and ground to form an epoxy resin composition.

To check the moisture resistance reliability of these compositions, we used an 8[ ]f flat package (using a lead frame with a 7-square stage) on a 6-square evaluation silicon element with opposing aluminum wiring. )K Each composition was transfer molded. At this time, the appearance was observed to see if there was any staining. Next, in order to check the soldering heat resistance of these molded bodies, they were treated as follows. Total 8 packs of 50 for each composition
After being left to absorb moisture for 72 hours at 5°C and 185% RH, it was immersed in solder flux and immersed in solder at 2600C for 10 seconds. The entire appearance of the packages was observed, and cracked packages were counted and removed. Furthermore, the package L has no cracks! , 125° C. and 100% RH (hereinafter referred to as POT), and the number of open defects due to corrosion of aluminum wiring was measured and compared. The evaluation results are shown in the table.

(Effects of the Invention) As is clear from the examples shown, the epoxy resin composition of the present invention has good moldability, has less package cranking after solder dipping, and Its moisture resistance reliability has been greatly improved, making it suitable for surface mount packages such as flat packages and ALOO.

Patent Applicant Denki Kagaku Kogyo Co., Ltd. Procedural Amendment July 20, 1988 Director General of the Patent Office Yoshi 1) Takeshi Moon 1, Indication of the Case Patent Application No. 1988], 51942 No. 2, Name of the Invention Epoxy Resin Composition Item 3. Relationship with the case of the person making the amendment Address of the patent applicant ■100 Detailed explanation of the invention in the specification 1-4-1 Yurakucho, Chiyoda-ku, Tokyo Column 5, Contents of the amendment (1) Specification No. 19 Approximately 150 as rx and y in page table 4
Correct it to ``approximately 150 with 0j as rx+y''.

Claims (8)

[Claims] (1) (A) Epoxy resin (B) Phenol resin curing agent (C) Silicone oligomer shown by the following formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [X in the above formula is an epoxy group, a mercapto group, an amino group,
It is an alkyl group or an aryl group containing a ureido group, a hydroxyphenyl group, or a carboxyl group, and R^1, R^2, R^3, R^4, R^5, and R^6 are each methyl, ethyl, or phenyl. is a group, n
represents an integer between 4 and 25. ] (D) Among the silane coupling agents represented by the following formula, those in which Y has a functional group capable of reacting with the above X ▲ Numerical formula, chemical formula,
There are tables, etc. ▼ [Y in the above formula is an alkyl group having an epoxy, mercapto, amino, diamino, or ureido group, R^7 is a methyl, ethyl, methoxy, or ethoxy group, and R^8 is a methoxy or ureido group. Indicates an ethoxy group. ] Above 4
An epoxy resin composition for inhibiting semiconductors whose main ingredients are: (2) The epoxy resin composition according to claim (1), wherein X in the silicone oligomer is an alkyl group containing an epoxy group, and Y in the silane coupling agent is an alkyl group having a mercapto group. (3) The epoxy compound according to claim (1), wherein X of the silicone oligomer is an alkyl group containing an epoxy group, and Y of the silane coupling agent is an alkyl group having an amino and/or ureido group. Resin composition. (4) An epoxy resin according to claim (1), wherein X of the silicone oligomer is an alkyl group containing an amino group or a ureido group, and Y of the silane coupling agent is an alkyl group having an epoxy group. Composition. (5) The epoxy resin composition according to claim (1), wherein X of the silicone oligomer is an alkyl group containing a mercapto group, and Y of the silane coupling agent is an alkyl group having an epoxy group. (6) The epoxy resin composition according to claim (1), wherein X of the silicone oligomer is an alkyl group containing a hydroxyphenyl group, and Y of the silane coupling agent is an alkyl group having an epoxy group. . (7) The epoxy resin composition according to claim (1), wherein X of the silicone oligomer is an alkyl group containing a carboxyl group, and Y of the silane coupling agent is an alkyl group containing an epoxy group. (8) The epoxy resin composition according to claims (2) to (7), wherein n of the silicone oligomer is 4 or more and 16 or less.