KR19980057177A - Manufacturing method of low stress modified silicone epoxy resin for semiconductor device encapsulation and resin composition for semiconductor device encapsulation containing same - Google Patents

Abstract

The present invention relates to a method for producing a low-stressed silicone-modified epoxy resin for semiconductor element encapsulation, and an epoxy resin composition using the same, more specifically, a silicone oil having a molecular weight of 200-1,000 in a silicone oil having a sock end or single-ended amine group. And a method of preparing a low stress silicone modified epoxy resin by reacting a mixture of a silicone oil having a molecular weight of 1,500-20,000 with one or a mixture of biphenyl type epoxy resins and bisphenol A type epoxy resins under reduced cost. An epoxy resin composition for semiconductor element sealing containing a low stress silicone modified epoxy resin.

Description

Manufacturing method of low stress modified silicone epoxy resin for semiconductor device encapsulation and resin composition for semiconductor device encapsulation containing same

The present invention relates to a method for producing a low-stressed silicone-modified epoxy resin for semiconductor element encapsulation, and an epoxy resin composition using the same, more specifically, a silicone oil having a molecular weight of 200-1,000 in a silicone oil having a sock end or single-ended amine group. And a method of preparing a low stress silicone modified epoxy resin by reacting a mixture of a silicone oil having a molecular weight of 1,500-20,000 with one or a mixture of biphenyl type epoxy resins and bisphenol A type epoxy resins under reduced cost. An epoxy resin composition for semiconductor element sealing containing a low stress silicone modified epoxy resin.

Recently, as semiconductor devices are highly integrated, when the semiconductor device having a fine surface structure is sealed, internal stress is generated due to a difference in the coefficient of thermal expansion between the encapsulating resin and the silicon chip. Since there is a problem in that the adhesion between the lead frames is lowered and the reliability is lowered, the internal stress must be lowered during sealing.

Known methods for lowering the thermal stress include increasing the amount of filler used or reducing the thermal expansion coefficient of the encapsulant using a filler having a low coefficient of thermal expansion, and rubber particles or oils such as butadiene rubber and silicone rubber in the epoxy base material. There is a method of reducing the elastic modulus by dispersing the rubber particles or oil to form a sea island structure in the base material.

However, when the amount of filler used is increased, not only the fluidity is lowered and the moldability is deteriorated, but also the elastic modulus is increased, so that stress is generated more than reducing the coefficient of thermal expansion, and when using a filler having a low coefficient of thermal expansion, Not only the wettability is lowered but also the moldability is worsened.

In addition, the method of dispersing the rubber or oil to lower the elastic modulus is contaminated with the mold, the glass transition temperature is lowered, the moisture resistance and heat resistance is lowered, especially in the case of using silicone oil to react with the epoxy resin in advance to the silicone-modified epoxy resin It is used after the manufacture, since an excessive amount of organic solvent is used and a process for recovering it is required, which causes problems such as environmental pollution and low production yield. In addition, unreacted silicone oil may remain and cause mold contamination. In addition, there is a problem that the size and distribution of silicon particles that affect the fracture toughness of the final epoxy resin composition cannot be controlled in the manufacturing process under an organic solvent. In addition, when a polyfunctional epoxy resin having three or more epoxies in one molecule is used alone to improve the glass transition temperature, problems such as mold contamination, an increase in elastic modulus, and a decrease in moisture resistance may occur, although they have a high glass transition temperature. .

Therefore, in the present invention, the silicone-modified epoxy resin is manufactured under cost, thereby simplifying the process, maximizing yield, minimizing environmental pollution, and improving the thermal shock resistance, moisture resistance, and moldability using the silicone-modified epoxy resin thus prepared. The purpose is to provide a silicone-modified epoxy resin composition for sealing a semiconductor device.

In order to achieve the above object, in the present invention, at least two kinds of silicone oil having a sock end or single terminal amine group and one or two or more epoxy resins having an epoxy group at the sock end are added and reacted under reduced cost to reduce stress-modified silicone. After the epoxy resin was prepared, a curing agent, an inorganic filler, a curing accelerator, a coupling agent, a lubricant, a flame retardant, a coloring agent, a mold release agent, and the like were added thereto to prepare an epoxy resin composition for semiconductor element encapsulation.

The low stress silicone modified epoxy resin production method of the present invention is described as follows.

First, a low molecular weight silicone oil having a molecular weight of 200-1,000 and a high molecular weight silicone oil having a molecular weight of 1,500-20,000 are mixed in a weight ratio of 5: 1-1: 5 among the silicone compounds that can be represented by the following general formula (I) A low-strain-modified epoxy resin according to the present invention is prepared by reacting one or two or more kinds of a non-neutral-type epoxy resin or a bisphenyl A-type epoxy resin under cost control.

[Formula 1]

In more detail describing the production method of the present invention, a silicone oil having a molecular weight of 200-1,000 and a silicone oil having a molecular weight of 1,500-20,000 having a sock-ended or single-ended amine group are primarily at room temperature in a weight ratio of 5: 1-1: 5. Mix. Depending on the weight ratio of the low molecular weight silicone oil and the high molecular weight silicone oil, the size and particle size distribution of the silicon particles in the final epoxy resin cured product may be controlled. The larger the weight ratio of the low molecular weight silicone oil, the smaller the size of the silicon particles and the narrower the particle distribution.

5-20 parts by weight of the mixture of the silicone oil and 95-80 parts by weight of a mixture of one or two or more epoxy resins are reacted at 110 ° C-150 ° C for 1 to 10 hours under cost. The epoxy resin that can be used in this reaction contains at least two epoxy groups in the sock end, and biphenyl type, bisphenol A type or mixtures thereof are suitable.

In the case of biphenyl type epoxy resin, epoxy equivalent is 170-200 and softening point is 100 degreeC-110 degreeC, and bisphenol-type epoxy resin is a liquid epoxy resin, epoxy equivalent 180-200, solid epoxy resin Is an epoxy equivalent of 300 -500 and a softening point of 70 ° C-90 ° C. In this reaction, bromine phenol blue is used as an indicator, and a tertiary amine is titrated to observe the progress of the reaction. When tertiary amine is formed in 90% or more with respect to all amine groups (primary amine group, secondary amine group, tertiary amine group), the reaction is stopped by lowering the temperature to room temperature.

The low molecular weight silicone oil used in this reaction acts as a compatibilizer in the reaction between the high molecular weight silicone oil and the epoxy resin to prevent the formation of gel particles during the reaction of the non-solvent and to prevent the formation of unreacted silicone oil in the final silicone modified epoxy resin. Suppress

Therefore, in the present invention, a low molecular weight silicone oil is used as a compatibilizer in the preparation of the silicone-modified epoxy resin, and the reaction between the epoxy resin and the high-molecular-weight silicone oil is possible even under cost reduction, thereby simplifying the silicone-modified epoxy resin manufacturing process. The manufacturing cost can be reduced, and the effect of preventing environmental pollution can be obtained. In addition, it is possible to improve the thermal shock resistance by controlling the size and size distribution of the silicon particles in the final silicone-modified epoxy resin cured product. In particular, when the silicone-modified biphenyl type epoxy resin is applied, the filler can be increased without poor formability of the encapsulant, thereby maintaining a low thermal expansion coefficient of the encapsulant, while suppressing an increase in the flexural modulus, thereby reducing the stress of the encapsulant. .

According to the method of the present invention, the prepared low-stressed silicone-modified epoxy resin is 100 parts by weight of the total modified epoxy resin composition for semiconductor encapsulation composed of an epoxy resin, a curing agent, a curing accelerator, a filler, a coupling agent, a lubricant, a coloring agent, a flame retardant, and the like. By blending 3 to 10 parts by weight with respect to the final can be prepared in the epoxy resin composition for semiconductor encapsulation.

Generally, the curing agent that can be used for the encapsulant includes amines, acid anhydrides, phenol resins, etc. In the present invention, a curing agent of phenol resins was used. 2 to 14 parts by weight of the curing agent is preferable with respect to 100 parts by weight of the total composition, but when used in less than 2 parts by weight, there is a problem that the reliability is lowered due to the unreacted epoxy resin, and when using more than 14 parts by weight unreacted curing agent There is a problem that the reliability is lowered due to the increase of.

In addition, as an inorganic filler, a spherical or non-spherical silica powder having a particle diameter of 0.1 to 50 micrometers is used alone or in combination, and 60 to 90 parts by weight is preferable with respect to 100 parts by weight of the total composition. When using less than 60 parts by weight, the thermal expansion rate is turned on, crack resistance, moisture resistance is lowered, when using more than 90 parts by weight fluidity is lowered.

In addition, a curing accelerator is used to promote the curing rate during the mixing and molding of the components of the composition, imidazole, 2-methylimidazole, 1-methylimidazole, 1,2-dimethylimidazole, 2 Imidazoles such as -phenylimidazole, 2-ethylimidazole, 4-methylimidazole, organic phosphine such as triphenylphosphine, tributylphosphine, dimethylphosphine, and tetraphenyl phosphonium bromide; Amine compounds such as phosphine salts, triethylamine, diethylenetriamine and triethylene tetraamine may be used alone or in combination, and 0.1 to 3 parts by weight is used for 100 parts by weight of the total composition.

In addition, the composition of the present invention contains 0.2 to 7 parts by weight of a lubricant such as natural wax, 0.2 to 7 parts by weight of a silane coupling agent, and 0.2 to 7 parts by weight of other flame retardants and coloring agents, respectively, based on 100 parts by weight of the total composition. It is used in combination.

The method of molding a semiconductor device using the composition of the present invention may be applied to a method such as compression molding or transfer molding. In the case of transfer molding, processing conditions may vary depending on the size, shape, and required characteristics of a molded article, but generally 160 ° C. After molding for 60-200 seconds at 180 ° C and post-curing at 160 ° C-180 ° C for at least 4 hours to produce the desired molded article.

Hereinafter, the preparation of the desired low-stressed silicon-modified epoxy resin and the epoxy encapsulation composition for semiconductor encapsulation using the same will be described in more detail with reference to Preparation Examples and Examples of the present invention. The category is not limited.

[Production Example 1]

In Formula I, X1 and X2 are both primary amine groups, Y is methyl group, and R is a silicone oil having a molecular weight of 900, which is an alkyl group having 3 carbon atoms, and a silicone oil having a molecular weight of 3,000 of the same structure in a 1: 1 weight ratio. 10 parts by weight of this mixture was added dropwise to 90 parts by weight of a biphenyl type epoxy resin (epoxy equivalent 185, softening point 106 ° C.) dissolved in a reaction vessel at 140 ° C. for 5 minutes, followed by stirring for 1-2 hours to obtain a product. . At this time, no organic solvent is used. Hereinafter, this product is referred to as low stress modifier A.

[Production Example 2]

The silicone oil having the same structure as the silicone oil used in Preparation Example 1 was mixed with a silicone oil having a molecular weight of 900 and a silicone oil having a molecular weight of 7,000 in a 1: 1 weight ratio, and then proceeded in the same manner as in Preparation Example 1 to obtain a product. Hereinafter, this product is referred to as low stress modifier B.

[Manufacture example 3]

A silicone oil having the same structure as the silicone oil used in Preparation Example 1 was mixed with a silicone oil having a molecular weight of 900 and a silicone oil having a molecular weight of 12,000 in a 1: 1 weight ratio, and then proceeded in the same manner as in Preparation Example 1 to obtain a product. This product is hereinafter referred to as low stress modifier C.

Comparative Example 1

As a silicone oil having the same structure as the silicone oil used in Preparation Example 1, only one kind of silicone oil having a molecular weight of 3,000 was used to proceed in the same manner as in Preparation Example 1 to obtain a product. This product is hereinafter referred to as denaturant D.

In Preparation Example 1-3 and Preparation Comparative Example 1-2, in order to compare the properties of the low-stressed silicone modifier and the modifier obtained in the Preparation Example and Comparative Example, only the curing agent was added to the silicone-modified epoxy resin and cured. No fillers or other additives were used.

Production Example 1

81.3 parts by weight of the low stress modifier A and 18.7 parts by weight of diaminodiphenylmethane as a curing agent were mixed at 110 ° C., then cured at 130 ° C. for 2 hours under vacuum, followed by post-curing at 180 ° C. for 6 hours. An epoxy resin hardened | cured material is obtained.

Production Example 2

Except for using 81 parts by weight of the low stress modifier B and 19 parts by weight of diaminodiphenylmethane, the same procedure as in Production Example 1 was carried out to obtain a silicone-modified epoxy resin cured product.

Production Example 3

Proceed in the same manner as in Preparation Example 1, except that 81 parts by weight of the low stress modifier C and 19 parts by weight of diaminodiphenylmethane were used to obtain a silicone-modified epoxy resin cured product.

[Manufacture Comparative Example 1]

Except for using 78.8 parts by weight of biphenyl type epoxy resin and 21.2 parts by weight of diaminodiphenylmethane, instead of the low stress modifier A in Preparation Example 1, the procedure was carried out as in Preparation Example 1 to obtain a cured epoxy resin. Get

[Manufacture Comparative Example 2]

A silicone-modified epoxy resin cured product was obtained in the same manner as in Preparation Example 1, except that 80.5 parts by weight of the modifying agent D was used instead of the low stress modifier A in the preparation example 1, and 19.5 parts by weight of diaminodiphenylmethane was used. .

How to measure

The physical properties of the silicone-modified epoxy cured product prepared above were measured using the same method as in Table 1 below, and the results are shown in Tables 3 and 4 below, and the compounding ratios are summarized in Table 2 below.

TABLE 1

1) Flexural Strength: ASTM-D-790

2) Flexural Modulus: ASTM-D-790

3) Glass Transition Temperature: Dynamic Mechanical Thermal Analysis (10Hz, 3 ℃ / min)

4) Fracture Toughness: ASTM-D-5045

5) Silicon particle size and distribution: electron microscope (SEM)

TABLE 2

TABLE 3

TABLE 4

Example 1

5 parts by weight of the low stress modifier A, 75 parts by weight of molten silica as an inorganic filler, 8.85 parts by weight of a biphenyl epoxy resin (epoxy equivalent 185) as an epoxy resin, and a novolak-type phenolic resin (hydroxyl equivalent 107, softening point 84) as a curing agent 7.75 parts by weight, 0.5 parts by weight of carbon black as a coloring agent, 0.15 parts by weight of triphenyl phosphine as a curing accelerator, 0.2 parts by weight of polyethylene wax and 0.2 parts by weight of canuba wax as a lubricant, and evenly rolled and mixed at 70-120 ° C. The composition for encapsulation of the present invention was prepared by kneading using a twin extruder or kneader, then cooling, pulverizing and tableting.

Example 2

A sealing composition was prepared in the same manner as in Example 1, except that 5 parts by weight of the low stress modifier B was used instead of the low stress modifier A.

Example 3

A sealing composition was prepared in the same manner as in Example 1, except that 5 parts by weight of the low stress modifier C was used instead of the low stress modifier A.

Example 4

5 parts by weight of the low stress modifier A, 75 parts by weight of molten silica as an inorganic filler, 9.07 parts by weight of a cresol novolac-type epoxy resin (epoxy equivalent 198, softening point 65 ° C.) as an epoxy resin, and a novolak-type phenol resin as a curing agent ( Hydroxyl equivalent 107, Softening point 84 ° C) 7.53 parts by weight, 0.5 parts by weight of carbon black as colorant, 0.15 parts by weight of triphenyl phosphine as curing accelerator, 0.2 parts by weight of polyethylene wax and 0.2 parts by weight of canuba wax as a lubricant, 70 The composition for encapsulation of the present invention was prepared by kneading using a two-roll or twin extruder or kneader at ˜120 ° C., then cooling, pulverizing and tableting.

Example 5

A sealing composition was prepared in the same manner as in Example 4, except that 5 parts by weight of the low stress modifier B was used instead of the low stress modifier A.

Example 6

An encapsulation composition was prepared in the same manner as in Example 4, except that 5 parts by weight of the low stress modifier C was used instead of the low stress modifier A.

Comparative Example 1

Except for the use of the modified agent D in place of the low stress modifier A in Example 1 was prepared in the same manner as in Example 1 a composition for sealing.

Comparative Example 2

Except for the low stress modifier A in Example 1, a composition for encapsulation was prepared in the same manner as in Example 1 in the same formulation as in Table 5.

Comparative Example 3

A sealing composition was prepared in the same manner as in Example 4, except that 5 parts by weight of the modifying agent D was used instead of the low stress modifier A.

Comparative Example 4

Except for the low stress modifier A in Example 4, a composition for encapsulation was prepared in the same manner as in Example 4 in the same formulation as in Table 5 below.

How to measure

The epoxy resin composition (compound shown in Table 5) for encapsulating the semiconductor device prepared above was cured at 175 ° C. for 180 seconds using a transfer molding press, and then cured at 175 ° C. for 4 hours in a hot air circulation oven. Physical properties of the obtained test piece were measured in the following manner, and the results are shown in Table 6 below.

Property measurement method

1) Flexural strength and flexural modulus: According to ASTM-D-790, flexural specimens of 12.68 * 6.44 * 100 (㎜) were formed under conditions of 175 ℃, 70Kg / ㎠ and molding time of 180 seconds and heated in 175 ℃ hot air circulation oven. Post-cure for 4 hours at and measured using UTM at 25 ℃ and 215 ℃.

2) Linear expansion coefficient and glass transition temperature: measured using TMA at a temperature increase rate of 5 ℃ / min. In accordance with ASTM-D-696.

3) Gel time: HOT PLATE METHOD, 175 ℃

4) Moisture Absorption Rate: The test piece of 50 mm diameter and 2 mm thickness was treated under the same conditions as the test piece of flexural strength and flexural modulus at 121 ° C., 2 ATM, 24 hours, and 100% relative humidity to calculate the weight.

5) Spiral Prow: Measured under conditions of 175 ° C and 70Kg / cm 2 in accordance with EMMI-166.

6) Crack resistance after absorption: Epoxy resin composition prepared with 208-pin QFP for 180 seconds under conditions of 175 ° C. and 70 Kg / cm 2, followed by post-curing for 4 hours in a hot air circulation oven at 175 ° C. After 48 hours of treatment in an atmosphere of 85 ° C./85% RH, the IR leaf (245 ° C.) was subjected to two cycles for 30 seconds, and then the number of cracks in the package was measured.

TABLE 5

TABLE 6

As described above, in the case of transferring and encapsulating various semiconductor devices using the silicon-modified epoxy resin composition of the present invention, cracks are satisfied while satisfying general characteristics such as heat resistance, moisture resistance, thermal conductivity, electrical insulation envoys, and mechanical strength. The result which has the characteristic excellent in the characteristic can be obtained.

By producing low-stressed silicone-modified epoxy under cost, it is possible to simplify the manufacturing process, improve yield, and minimize environmental pollution.The epoxy resin composition thus prepared has a low coefficient of linear expansion and a flexural modulus to reduce stress, thermal shock resistance, and The wettability and moldability are improved and high reliability is shown.

Claims (7)

(A) A mixture of a silicone oil having a molecular weight of 200-1,000 and a silicone oil having a molecular weight of 1,500-20,000 in a silicone oil having a sock end or single terminal amine group represented by the following formula (I): (B) a biphenyl type epoxy resin, A method for producing a low-stressed silicone-modified epoxy resin, characterized in that it reacts with one or a mixture of bisphenol A epoxy resins under cost control. [Formula I] The low stress silicone according to claim 1, wherein the mixed weight ratio of the silicone oil having a molecular weight of 200 to 1,000 and the silicone oil having a molecular weight of 1,500 to 20,000 in a mixture of the silicone oil having an amine group is 5: 1 to 1: 5. Method for producing modified epoxy resin. The method of claim 1, wherein the biphenyl type epoxy resin has an epoxy equivalent of 170 to 200 and a softening point of 100 ° C to 110 ° C, and the bisphenol A type epoxy resin has an epoxy equivalent of 180 to 200 in the case of a liquid epoxy resin, In the case of a solid epoxy resin, an epoxy equivalent is 300-500 and a softening point is 70 degreeC-90 degreeC, and the manufacturing method of the low stress silicone modified epoxy resin characterized by containing at least 2 or more epoxy groups in a molecule | numerator. The low-stressed silicone modification according to claim 1, wherein 5 to 20 parts by weight of the silicone oil mixture (a) and 95 to 80 parts by weight of the epoxy resin of (b) or one or two mixtures are reacted. Method for producing an epoxy resin. The method of claim 1, wherein the reaction is carried out at a cost of 1 to 10 hours at a temperature of 120 ° C. to 150 ° C. under low cost. 3 to 10 parts by weight of the low-stressed silicone-modified epoxy resin prepared by the method of any one of claims 1 to 5, 3 to 15 parts by weight of a biphenyl-type epoxy resin or cresol novolac epoxy resin, and a curing agent 2 to 14 An epoxy resin composition for semiconductor element encapsulation, comprising: parts by weight, 60 to 90 parts by weight of filler, 0.1 to 3 parts by weight of curing accelerator, and 0.2 to 7 parts by weight of additives such as coupling agents, lubricants, flame retardants, and colorants. 7. The epoxy resin composition for semiconductor element encapsulation according to claim 6, wherein the filler is a spherical or non-spherical silica powder having a particle diameter of 0.1 to 50 µm.