KR100540536B1 - Epoxy resin composition for semiconductor sealing with improved reliability - Google Patents

Abstract

The present invention relates to an epoxy resin composition for semiconductor encapsulation, and more particularly, a phenol resin obtained by pretreating (A) an epoxy resin, (B) a phenol resin, a methacryl-butadiene-styrene copolymer and a silane coupling agent, An epoxy resin composition for semiconductor encapsulation with improved reliability consisting essentially of (C) silica powder, (D) silicone oil and (E) silicone rubber. The epoxy resin composition of this invention was able to obtain the highly reliable epoxy resin composition which was excellent in high temperature-moisture resistance and crack resistance thermal stress with low stress, and was high in adhesive force.

Description

Epoxy resin composition for semiconductor sealing with improved reliability

The present invention relates to an epoxy resin composition for semiconductor encapsulation, which is used for electric and electronic parts having low stress and excellent moisture resistance, crack resistance and thermal stress.

Epoxy resins have been widely used for sealing semiconductor devices, electronic parts, and electrical parts as highly reliable insulating materials because of their excellent electrical insulating properties, mechanical properties, moisture resistance, and the like. In particular, encapsulation of semiconductor devices using epoxy resins has been used as mainstream in resin encapsulation because of their low cost and mass production.

The characteristics required for resin as a semiconductor encapsulation material are high corrosion resistance to prevent corrosion of metal wiring on the semiconductor device and high thermal shock resistance to prevent disconnection caused by thermal shock of metal wiring connecting the semiconductor device and the lead frame. This has been required.

In recent years, with the higher integration of semiconductor devices, metal wirings have become smaller and semiconductor chips have become larger in size, and resin package cages have become smaller and thinner. As described above, when the miniaturized and thin resin package is mounted on a semiconductor element, the package needs to be subjected to a nap soldering process for about 5 to 20 seconds at a high temperature of 240 to 260 ° C.

However, the small and thin package has a small thickness above and below the semiconductor element, and if soldering is performed at a high temperature, a crack occurs in the package or a problem that the moisture resistance of the resin encapsulant decreases. As a method that can cope with such a problem, it is necessary to lower the internal stress of the resin material.

In order to reduce the internal stress of the resin material, Japanese Laid-Open Patent Publication No. 3-74456 used a method of adding natural rubber to an epoxy resin, but in the case of using such modified resin, there is a disadvantage in that moisture resistance and the like are reduced.

Accordingly, it is an object of the present invention to provide an epoxy resin composition for semiconductor encapsulation that compensates for the shortcomings of the conventional epoxy resin encapsulant, is low in stress, excellent in adhesion to the lead frame, and particularly high in moisture resistance.

Epoxy resin composition of the present invention for achieving the above object

(A) 100 parts by weight of epoxy resin,

(B) 0.5 to 1.5-OH equivalents of phenol resin per 1 equivalent of epoxy resin,

(2) 5 to 50 parts by weight of methacryl-butadiene-styrene copolymer (hereinafter referred to as MBS resin) based on 100 parts by weight of the phenol resin;

(3) 30 to 150 parts by weight of a phenol resin obtained by pretreating 5 to 20 parts by weight of a silane coupling agent with respect to 100 parts by weight of the phenol resin,

(C) 400 to 1000 parts by weight of silica powder,

(D) 0.05 to 3.0 parts by weight of silicone oil, and

(E) It consists essentially of 0.05-5.0 weight part of silicone rubber.

The epoxy resin composition for semiconductor encapsulation of the present invention

(A) 100 parts by weight of epoxy resin,

(B) 0.5 to 1.5-OH equivalents of phenol resin per 1 equivalent of epoxy resin,

(2) 5 to 50 parts by weight of methacryl-butadiene-styrene copolymer (hereinafter referred to as MBS resin) based on 100 parts by weight of the phenol resin;

(3) 30 to 150 parts by weight of a phenol resin obtained by pretreating 5 to 20 parts by weight of a silane coupling agent with respect to 100 parts by weight of the phenol resin,

(C) 400 to 1000 parts by weight of silica powder,

(D) 0.05 to 3.0 parts by weight of silicone oil, and

(E) Essentially contains 0.05-5.0 weight part of silicone rubber.

The epoxy resin composition of this invention contains the said 5 essential components.

The component (A) is an epoxy resin, and is not particularly limited. For example, a bisphenol-A type epoxy resin, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a biphenyl type epoxy resin, and an alicyclic epoxy resin , At least one selected from the group consisting of linear aliphatic epoxy resins, heterocyclic epoxy resins and halogen type epoxy resins, and contains two or more epoxy groups in one molecule.

In order to reduce the corrosion of the metal wiring of the semiconductor device, the epoxy resin used in the present invention is preferably an epoxy resin having a low content of chlorine ions, preferably 10 ppm or less, and a hydrolyzable chlorine powder of 500 Preference is given to using epoxy resins which are ppm or less.

Component (B) is a phenol resin pretreated with MBS resin and silane coupling agent as a curing agent of epoxy resin component (A), and its amount is 30 to 150 parts by weight based on 100 parts by weight of the epoxy resin of component (A). At this time, if the amount of the component (B) is less than 30 parts by weight, a problem that the degree of curing during curing of the epoxy resin composition is lowered, and if more than 150 parts by weight, the moisture absorption of the cured product cured with the epoxy resin composition increases Is generated, and the amount is preferably 55 to 100 parts by weight.

The phenol resin of (1) in the component of (B) is phenol novolak resin, cresol novolak resin, t-butyl phenol novolak resin, phenol aralkyl resin, nonylphenol resin, resol type phenol resin, bisphenol, for example. One or more selected from the group consisting of -A resin and dicyclopentadiene phenol resin, but is not limited thereto, characterized in that it contains at least two phenolic -OH groups in one molecule. At this time, it is preferable that -OH equivalent of a phenol resin is about 0.5-1.5 with respect to 1 equivalent of epoxy of an epoxy resin, and, as for the phenol resin used, More preferably, 0.9-1.1 are preferable. If the equivalent ratio of the epoxy resin and the phenol resin is out of the range, crack resistance may be deteriorated due to a decrease in strength of the epoxy resin composition.

(2) MBS resin of the said component (B) contains 30-70 weight% of butadiene units normally and can also be obtained by synthesis | combination, but it is marketed by this invention, and is a commercially available metabrene MBS resin of Mitsubishi Rayon. Was applied. At this time, the MBS resin includes 5 to 50 parts by weight, and preferably 10 to 40 parts by weight based on 100 parts by weight of the phenol resin. When the content of the MBS resin is less than 5 parts by weight, the effect of low stress at the time of application can not be seen, if it exceeds 50 parts by weight, the dispersibility during the treatment does not have good adverse effects on the flowability.

The silane coupling agent (3) of the component (B) is a silane coupling agent having a glycidyl group (hereinafter referred to as silane coupling agent-a) alone or a cyclohexyl epoxy group, an amino group, a mercapto group, a chloro group and a methacryl group silane. Coupling agent (hereinafter referred to as silane coupling agent-b), and preferably, the silane coupling agent-b includes a silane coupling agent containing a cyclohexyl epoxy group, an amino group, and a mercapto group. In addition, the content of the silane coupling agent is 5 to 20 parts by weight, preferably 5 to 15 parts by weight based on 100 parts by weight. If the content of the silane coupling agent is less than 5 parts by weight, the strength of the epoxy resin composition may be lowered. If the content of the silane coupling agent is more than 20 parts by weight, the treatment at the time of preparation of the pretreated phenol resin may be difficult. The weight ratio of silane coupling agent-a / silane coupling agent-b is 1/0 to 1/1. When the mixing ratio of the two silane coupling agents is out of the above range, it does not affect the improvement of adhesion between the resin composition and the lead frame.

The pretreatment method of component (B) melt | dissolves 100 weight part of phenol resins at the temperature of 130 degreeC-160 degreeC, and removes the water contained in a small amount in phenol resins under reduced pressure for 1-2 hours. After adding 5-50 weight part of MBS resins gradually to the said phenol resin, disperse | distributing for about 30 minutes, and adding 5-20 weight part of silane coupling agents gradually, and stirring for about 2 to 6 hours, component (B) is manufactured. .

The silica powder of component (C) may use fused silica or crystalline silica, but is not limited thereto. It may be of any shape such as crushed, spherical and fibrous. In addition, in order to prevent breakage, formability and low stress of the semiconductor device, it is preferable to use one cut into 100 to 200 mesh. In particular, when encapsulating a semiconductor device such as a memory element, the content of the radiation element is preferably 1.0 ppb or less in order to prevent soft errors.

The amount of the component (C) silica powder is suitably 400 to 1000 parts by weight based on 100 parts by weight of the component (A) epoxy resin, and preferably the amount is 600 to 900 parts by weight. If the amount of the component (C) silica powder is less than 400 parts by weight, a problem occurs that the strength of the cured product cured with the epoxy resin composition is lowered. The problem of deterioration arises.

The silicone oils of component (D) can be both reactive or non-reactive silicone oils, for example sock amine silicone oil, sock epoxy resin, sock phenol silicone oil, sock methyl silicone oil and branched epoxy One or more selected from the group consisting of silicone oils. As for content of the said component (D), 0.05-3.0 weight part is preferable with respect to 100 weight part of component (A) epoxy resins. If the content of (D) is less than 0.05 parts by weight, there is a problem that does not help to relieve the stress of the cured product cured with the epoxy resin composition, if exceeding 3.0 parts by weight, the moisture absorption of the cured product increases or the flowability is lowered Problem occurs.

The component (E) silicone rubber is not particularly limited and is selected from commercially available commercially available silicone rubbers, and its content is preferably 0.05 to 5.0 parts by weight based on 100 parts by weight of the component (A) epoxy resin. If the amount of use exceeds the above range, it may not affect the improvement of the reliability or may adversely affect the moldability.

Other necessary components include colorants such as carbon black, antimony flame retardants for securing flame retardancy, phosphorus flame retardants, and the like. In addition, a small amount of a release agent and a curing accelerator are required to facilitate the separation of the mold and the package.

As the curing accelerator, generally, any one capable of promoting the curing of the epoxy resin and the phenol resin may be used. For example, a phosphine-based or 2-methyl group such as triphenyl phosphine, tetraphenyl phosphine or tetraphenyl borate may be used. One or more selected from the group consisting of imidazoles such as midazoles and 2-ethyl-4-methyl imidazoles, and amines such as DBU or DBN.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Example

Production Examples 1-4

The preparation of the pretreated phenolic resin by phenol resin, MBS resin, and silane coupling agent was performed based on the formulation shown in Table 1 below. First, a phenol resin is melt | dissolved at 150 degreeC, pressure reduction is carried out at the pressure reduction degree of 100 Torr for about 1 hour, and the moisture absorbed by a phenol resin is completely removed during storage. MBS resin was added to the phenol resin from which the water was removed, and the mixture was stirred at 400 rpm for 30 minutes to disperse the MBS resin, and then the compounded amount of the silin coupling agent was slowly added dropwise over 20 minutes. When the dropwise addition of the silane coupling agent was completed, the reaction was carried out for 3 hours while maintaining the temperature at 150 占 폚 to obtain a pretreated phenol resin.

Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Phenolic Resin Phenolic novolac resin-OH equivalent = 106 g / Eq Softening point = 85 ° C 537 416 505 521 Phenolic Aralkyl Resin-OH Equivalent = 178 g / Eq Softening Point = 75 ° C * 121 * * MBS Resin Mitsubishi Rayon Average Grain Size = 160㎛ 100 200 200 150 Silane coupling agent Epoxy group 50 50 30 40 Amino group * * 20 * Mud Pottery * * * 10

Examples 1-4 and Comparative Examples 1-3

Preparation of the epoxy composition was weighed according to the formulation given in Table 2 below, it was sufficiently dispersed over 4 minutes using Two-Roll of 100 ~ 90 ℃, and then obtained by grinding it. The epoxy resin composition thus obtained was subjected to transfer molding at 175 ° C. for 120 seconds, and then post-cured at 175 ° C. for 6 hours to obtain a resin for semiconductor encapsulation.

Example Comparative example One 2 3 4 One 2 3 Epoxy Resin ¹ 104 94 98 101 111 107 106 Brominated epoxy resin ² 5 5 5 5 5 5 5 Phenolic novolac resin ³ * * * * 57 47 54 Phenolic Aralkyl Resin ⁴ * * * * * 14 * Preparation Example 1 68.7 * * * * * * Preparation Example 2 * 66.6 * * * * * Preparation Example 3 * * 75.5 * * * * Preparation Example 4 * * * 72.1 * * * Silica powder 800 800 800 800 800 800 800 Silicone oil ⁵ 2 2 2 2 2 2 * Antimony trioxide 15 15 15 15 15 15 15 Glycidolepoxy silane ⁶ * * * * 5 5 5 Carnauba wax 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Carbon black 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Triphenylphosphine 1.9 1.7 1.9 1.9 1.9 1.7 1.7

1 O-Cresol Novoloc type epoxy resin (Japan Gunpowder Co., Ltd.); Softening point 65 ° C; Epoxy equivalent 200 g / eq.

2 brominated phenol novolak resins (Japan Gunpowder Co., Ltd.); Bromine content 34% by weight.

3 phenol novolak resin (Meida Gunpowder Co., Ltd.); Softening point 80 ° C; -OH equivalent 100 g / eq.

4 P-Xylenenol phenol novolak resin (Meida Gunpowder Co., Ltd.); Softening point 65 ° C; -OH equivalent 175 g / eq.

5 diaminosilicone oil.

6 r-glycidyl propylenetrimethoxy silane.

The physical properties of the epoxy resin composition thus prepared were investigated and shown in Table 3 below.

Example Comparative example One 2 3 4 One 2 3 Melt viscosity 250 200 280 270 250 220 230 Linear expansion coefficient (10 ^-6 / ℃) 15 13 13 14 15 15 16 Flexural modulus (㎏ / ㎠) 1700 1550 1600 1650 1950 1850 1950 Flexural Strength (㎏ / ㎠) 17 14.5 17 17 15 13 15 Solder Crackability (Defective / Sample) 0/20 0/20 0/20 0/20 10/20 12/20 20/20 PCT Test (Defective / Sample) 100 hours 0/20 0/20 0/20 0/20 0/10 1/8 - 200 0/20 0/20 0/20 0/20 1/10 1/8 - 300 0/20 0/20 0/20 0/20 3/10 3/8 - 400 1/20 0/20 0/20 0/20 5/10 5/8 - 500 2/20 0/20 0/20 0/20 7/10 7/8 - PCT Test (Defective / Sample) 100 cycles 0/20 0/20 0/20 0/20 0/20 0/20 0/20 200 0/20 0/20 0/20 0/20 1/20 1/20 3/20 300 0/20 0/20 0/20 0/20 3/20 3/20 8/20 400 0/20 0/20 0/20 0/20 8/20 6/20 12/20 500 1/20 0/20 0/20 0/20 11/20 8/20 20/20

As described above, the epoxy resin composition of the present invention is very useful as a semiconductor encapsulation having high stress resistance, high temperature resistance, crack resistance and thermal stress with high stress, and high reliability with high adhesion.

Claims (7)

(A) 100 parts by weight of epoxy resin, (B) 0.5 to 1.5-OH equivalents of phenol resin per 1 equivalent of epoxy resin, (2) 5 to 50 parts by weight of methacryl-butadiene-styrene copolymer with respect to 100 parts by weight of the phenol resin and (3) 30 to 150 parts by weight of a phenol resin obtained by pretreating 5 to 20 parts by weight of a silane coupling agent with respect to 100 parts by weight of the phenol resin, (C) 400 to 1000 parts by weight of silica powder, (D) 0.05 to 3.0 parts by weight of silicone oil, and (E) The epoxy resin composition for semiconductor sealing with improved reliability which consists essentially of 0.05-5.0 weight part of silicone rubber. The epoxy resin of claim 1, wherein the component (A) epoxy resin is a bisphenol-A type epoxy resin, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a biphenyl type epoxy resin, an alicyclic epoxy resin, or a linear aliphatic epoxy resin. 1 or more selected from the group consisting of a heterocyclic epoxy resin and a halogen-type epoxy resin, epoxy resin composition for improved semiconductor encapsulation, characterized in that it contains two or more epoxy groups in one molecule. The epoxy resin composition for semiconductor encapsulation with improved reliability according to claim 1, wherein the amount of the component (B) is 55 to 100 parts by weight based on 100 parts by weight of the (A) epoxy resin. The phenol resin (1) of the component (B) is a phenol novolak resin, a cresol novolak resin, a t-butylphenol novolak resin, a phenol aralkyl resin, a nonylphenol resin, a resol-type phenol resin, An epoxy resin composition for improved reliability of semiconductor encapsulation, wherein at least one selected from the group consisting of a bisphenol-A resin and a dicyclopentadiene phenol resin contains at least two phenolic -OH groups in one molecule. The epoxy resin composition for semiconductor encapsulation with improved reliability according to claim 1, wherein the phenol resin has a -OH equivalent weight of 0.9 to 1.1 of the phenol resin relative to 1 equivalent of epoxy of the epoxy resin. The silane coupling agent (3) of the component (B) is a silane coupling agent having a glycidyl group (silane coupling agent-a) alone or a cyclohexyl epoxy group, an amino group, a mercapto group, a chloro group and a methacryl. A silane coupling agent (silane coupling agent-b), wherein the weight ratio of the silane coupling agent-a / silane coupling agent-b is 1/0 to 1/1, wherein the epoxy resin composition for improved semiconductor encapsulation is improved. . The component (B) is dissolved in 100 parts by weight of the phenol resin at a temperature of 130 ℃ to 160 ℃, and then removes the water contained in the phenol resin under reduced pressure for 1 to 2 hours, methacryl-butadiene -After slowly adding 5 to 50 parts by weight of a styrene copolymer, dispersing it for about 30 minutes, and slowly adding 5 to 20 parts by weight of the silane coupling agent, it is prepared by stirring for about 2 to 6 hours. Epoxy resin composition for improved semiconductor encapsulation.