KR100414205B1 - Epoxy resin composition for encapsulating semiconductor device - Google Patents

Abstract

The present invention relates to an epoxy resin composition for sealing semiconductor elements, more specifically

(1) Ortho cresol novolac resin of the following formula (1),

Diglycidyl hexamethyl biphenyl epoxy resin of formula

Or 5.95-15.00 weight percent of these mixtures,

(2) phenol novolac resin and cyclopentadiene resin of formula (3)

Or 3.00-10.00 weight percent of these mixtures,

(3) 0.10 to 0.30% by weight of a curing accelerator,

(4) 0.05 to 0.40% by weight of potential curing catalyst,

(5) inorganic filler 70.00-90.00% by weight,

(6) 0.10 to 3.00 wt% of a diazo-based condensed pigment of the following formula (4) and

(7) 0.80 to 1.50 wt% flame retardant

It relates to an epoxy resin composition for semiconductor element sealing comprising a, the epoxy resin composition for semiconductor element sealing of the present invention is not only excellent in flame retardancy and crack resistance, but also excellent in the sharpness of laser marking, small, thin Useful for package manufacture.

[Formula 1]

(In the formula, G is a glycidyl group, R is a methyl group or a hydroxyl group, n is 0 to 5)

[Formula 2]

(Wherein R is a methyl group or a hydrogen group, n is 0-3)

[Formula 3]

(Wherein R is a methyl group or a hydrogen group, n is 0-4)

[Formula 4]

(Wherein R is a methyl group or a hydrogen group, R 'is a hydrogen group, a methyl group or a chlorine group, and M is an azo group)

Description

Epoxy resin composition for encapsulating semiconductor device

The present invention relates to an epoxy resin composition for sealing semiconductor devices, and more particularly, ortho cresol novolac resin and / or diglycidyl hexamethyl biphenyl epoxy resin, phenol novolac resin and / or cyclopentadiene resin, An epoxy resin composition for sealing semiconductor elements, including a curing accelerator, a latent curing catalyst, an inorganic filler, a diazo-based condensation dye, and a flame retardant, which have enhanced adhesion and crack resistance to the surface of the wafer chip, and improved type definition of laser marking. will be.

In recent years, the degree of integration of semiconductor devices has been improved day by day, and thus the size of wirings, the size of devices and the size of multilayer wirings are rapidly progressing. On the other hand, in the case of the package which protects a semiconductor element from an external environment, compactness and thickness reduction are accelerating from the viewpoint of high-density mounting to a printed board, ie, surface mounting.

As described above, in a resin-sealed semiconductor device in which a large semiconductor device is sealed in a small and thin package, the frequency of failure due to a package crack or an aluminum pad becomes very high due to thermal stress caused by temperature and humidity changes in the external environment. There is a problem that vision errors occur frequently due to the lack of type definition in the marking process.

In order to solve this problem, there is a strong need to develop a method for improving the reliability of the epoxy resin composition for sealing semiconductor devices, and as a specific method, various rubber components, in particular, a modifier such as a silicone polymer having excellent thermal stability A method for achieving low elasticity by adding (see Japanese Patent Application Laid-Open No. 63-1894, Japanese Patent Application Laid-open No. Hei 5-291436), and a method for improving the laser marking characteristics by controlling the content and particle size distribution of the filler have been proposed. come.

However, conventional methods that rely only on carbon black as colorants have not been able to fundamentally improve the laser marking clarity of small, thin packages.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art as described above, and to provide an epoxy resin composition for sealing semiconductor elements having improved laser marking characteristics by using a diazo-based condensation dye as a colorant.

That is, the present invention

(1) Ortho cresol novolac resin of the following formula (1),

Diglycidyl hexamethyl biphenyl epoxy resin of formula

Or 5.95-15.00 weight percent of these mixtures,

(2) phenol novolac resin and cyclopentadiene resin of formula (3)

Or 3.00-10.00 weight percent of these mixtures,

(3) 0.10 to 0.30% by weight of a curing accelerator,

(4) 0.05 to 0.40% by weight of potential curing catalyst,

(5) inorganic filler 70.00-90.00% by weight,

(6) 0.10 to 3.00 wt% of a diazo-based condensed pigment of the following formula (4) and

(7) 0.80 to 1.50% by weight of flame retardants,

It provides an epoxy resin composition for sealing a semiconductor device comprising a.

(In the formula, G is a glycidyl group, R is a methyl group or a hydroxyl group, n is 0 to 5)

(Wherein R is a methyl group or a hydrogen group, n is 0-3)

(Wherein R is a methyl group or a hydrogen group, n is 0-4)

(Wherein R is a methyl group or a hydrogen group, R 'is a hydrogen group, a methyl group or a chlorine group, and M is an azo group)

Hereinafter, the present invention will be described in more detail.

The epoxy resin composition for sealing a semiconductor device of the present invention includes an epoxy resin, a curing agent, a curing accelerator, a latent curing catalyst, an inorganic filler, a coloring agent, and a flame retardant. The components of the epoxy resin composition of the present invention will be described in detail below. Same as

The epoxy resin (hereinafter referred to as component (1)) used in the present invention is an ortho cresol novolak resin of formula (1), a diglycidyl hexamethyl biphenyl epoxy resin of formula (2) or a mixture thereof.

[Formula 1]

(In the formula, G is a glycidyl group, R is a methyl group or a hydroxyl group, n is 0 to 5)

[Formula 2]

(Wherein R is a methyl group or a hydrogen group, n is 0-3)

The diglycidyl hexamethyl biphenyl epoxy resin in the component (1) is a high purity epoxy resin having an epoxy equivalent of 190 to 230 and a softening point of 70 to 110 ° C., which is 2,2 3,3 5,5-hexamethyl- It is obtained by adding epichlorohydrin to 4,4-biphenol and ring-opening at a low temperature. Detailed preparation methods are described in the following preparation examples.

The diglycidyl hexamethyl biphenyl epoxy resin thus obtained has a rigid skeleton structure and is superior in mechanical strength and shrinkage properties as compared to conventional biphenyl epoxy resins. Significant improvement can be obtained, and there is an advantage of improving adhesion to the chip as well as improving crack resistance during curing.

The content of the component (1) is preferably 5.95 to 15.00% by weight based on the total composition, wherein the content of diglycidyl hexamethyl biphenyl epoxy resin in the component (1) is 1.00 to 8.00 weight based on the total composition It is preferable that it is%, and the object of the present invention cannot be achieved outside the above range.

The curing agent (hereinafter referred to as component (2)) used in the present invention is a phenol novolak resin, a cyclopentadiene resin of the formula (3) or a mixture thereof.

[Formula 3]

(Wherein R is a methyl group or a hydrogen group, n is 0-4)

The content of the component (2) is preferably from 3.00 to 10.00% by weight based on the total composition, a large amount of unreacted epoxy group or phenol group is generated when out of the above range will give a poor result in reliability.

The curing accelerator used in the present invention (hereinafter referred to as component (3)) is a component necessary to accelerate the curing reaction of the component (1) and the component (2), for example benzyldimethylamine, triethanolamine, triethylene Tertiary amines such as diamine, dimethylaminoethanol and tri (dimethylaminomethyl) phenol; And organic phosphines such as triphenylphosphine, diphenylphosphine, and phenylphosphine, and the like, and one or two or more thereof may be used alone or in combination.

The content of the component (3) is preferably 0.10 to 0.30% by weight based on the total composition. If the content is less than 0.10% by weight, the curing rate is slow, the productivity is poor, and if the content is more than 0.30% by weight, the desired curing properties are not obtained, and storage stability is not good.

The latent curing catalyst (hereinafter referred to as component (4)) used in the present invention is a component necessary for properly controlling the curing rate due to the increase in the reaction rate due to the introduction of diglycidyl hexamethyl biphenyl epoxy resin. Triazine isocyanate imidazole compounds; And triphenylphosphine adducts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate, and one or two or more of these may be used alone or in combination.

The content of the component (4) is preferably 0.05 to 0.40% by weight based on the total composition, it can not achieve the object of the present invention outside the above range.

As the inorganic filler (hereinafter referred to as component (5)) used in the present invention, it is preferable to use fused or synthetic silica having an average particle size of 0.1 to 35.0 µm.

The content of the component (5) is preferably 70.00 to 90.00% by weight based on the whole composition. If the content is less than 70.00% by weight, not only sufficient strength and low thermal expansion can be realized, but also moisture is easily penetrated, which is fatal to the reliability deterioration. On the other hand, if the content is more than 90.00% by weight is not good because there is a fear that the flow characteristics of the composition is lowered, the molding is worse.

The colorant (hereinafter referred to as component (6)) used in the present invention is a diazo-based condensation dye of the following formula (4).

[Formula 4]

(Wherein R is a methyl group or a hydrogen group, R 'is a hydrogen group, a methyl group or a chlorine group, and M is an azo group)

The content of the component (6) is preferably 0.10 to 3.00% by weight based on the total composition. If the content is less than 0.10% by weight, sufficient laser marking improvement cannot be obtained. If the content is more than 3.00% by weight, it is not good because reliability cannot be maintained under severe conditions for a specified time in forming a semiconductor package.

In the present invention, the diazo-based condensation dye may be used as a colorant by mixing with a conventional organic and / or inorganic colorant, and the content of the diazo-based condensation dye is preferably 20% by weight or more based on the total colorants.

Flame retardants used in the present invention (hereinafter referred to as component (7)) 100 parts by weight of polyglycidyl ether brominated phenol epoxy having an epoxy equivalent weight of 250 to 300 and a bromine content of 35 to 40% by weight and 20 to 40 weight of antimony trioxide If the content of the antimony trioxide is lower than the above range, it may not meet UL 94 VO flame retardancy standard, and if it is more than the above range, soot may be generated so that the bad marking and reliability in the post process may be adversely affected. It is not good because it is crazy.

The content of component (7) is preferably 0.80 to 1.50% by weight based on the total composition. If the content is less than 0.80% by weight of UL94 V-O level of flame retardancy can not be achieved, if the content exceeds 1.50% by weight in the high temperature, high pressure and high humidity environment is not good because the chip corrosion caused by bromine and antimony trioxide.

In addition, the epoxy resin composition of the present invention includes a release agent such as higher fatty acids, natural fatty acids, paraffin wax, ester wax; Crosslinking enhancers; Flame retardant aids; And a labeling agent etc. can also be added as needed.

The epoxy resin composition of the present invention is uniformly mixed using the above-mentioned components using a Henssel mixer or Loedige mixer, and then melt kneaded with a roll mill or kneader, cooled and Through the grinding process, it is made into a final powder product.

As a method of sealing a semiconductor device using the epoxy resin composition prepared as described above, a low pressure transfer molding method is most commonly used, but molding may also be performed by injection or casting.

Hereinafter, the present invention will be described in more detail with reference to examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Production Example

After adding 0.3 mol of 2,2 3,3 5,5-hexamethyl-4,4-biphenol and 6.0 mol of epichlorohydrin to a round-necked flask, 0.01 mol of aqueous tetraammonium chloride solution was slowly added dropwise at After reacting for 8 hours under the atmosphere, the temperature was lowered to 5 ° C. or lower, 50% sodium hydroxide solution was added thereto, and the reaction was continued for 4 hours while maintaining the temperature. After the reaction was completed, an aqueous methanol solution was added to the reaction mixture, which was then vigorously stirred, followed by purification and drying to obtain diglycidyl hexamethyl biphenyl epoxy resin used in the present invention.

Examples 1-3

As shown in Table 1 below, each component was weighed, and then uniformly mixed with a Henschel mixer to prepare a primary composition in powder form, melt kneaded at 100 ° C. within 10 minutes using a kneader, and then cooled and ground. The final epoxy resin composition was prepared through the process. The epoxy resin composition thus obtained was molded into a SMD (surface mount) type SOT package semiconductor device at 175 ° C. for 60 seconds using an MPS (Multi Plunger System) molding machine, followed by post-curing at 175 ° C. for 3 hours to produce a specimen. . Physical properties were evaluated for each of the specimens, and the evaluation results are shown in Table 1 below.

Comparative Examples 1 to 3

After weighing each component as shown in Table 2 below, an epoxy resin composition was prepared in the same manner as in the above Examples, and a specimen was prepared. The physical properties of each of the specimens thus obtained were evaluated, and the evaluation results are shown in Table 2 below.

Composition Example 1 Example 2 Example 3 Ortho Cresol Noble Epoxy Resin 8.50 5.10 1.40 Diglycidylhexamethylbiphenyl epoxy resin 4.70 6.70 5.12 Brominated epoxy 0.76 0.80 0.73 Antimony trioxide 0.15 0.20 0.3 Cyclo Pentadiene Curing Agent 1.85 3.40 3.00 Phenolic Noblec Hardener 6.20 3.04 0.90 Triphenylphosphine 0.17 0.12 0.10 Latent curing catalyst 0.07 0.09 0.05 Silica 77.00 80.00 87.80 Carbon black - 0.20 0.30 Diazo-Base Condensed Pigment 0.40 0.15 0.10 Carnauba Wax 0.10 0.10 0.10 Blood wax 0.10 0.10 0.10 Flame Retardant (UL94) V-0 V-0 V-0 CO ₂ laser marking color development Good Good Good definition Good Good Good Cold shock evaluation (10% or more occurrence of package crack and chip peeling) After 100 cycles 0/100 0/100 0/100 After 200 cycles 0/100 0/100 0/100 After 300 cycles 0/100 0/100 0/100

Composition Comparative Example 1 Comparative Example 2 Comparative Example 3 Ortho Cresol Noble Epoxy Resin 11.50 5.00 - Biphenyl epoxy resin - 4.00 7.00 Brominated epoxy 0.70 0.60 0.70 Antimony trioxide 0.30 0.30 0.20 Cyclo Pentadiene Curing Agent - - 3.50 Phenolic Noblec Hardener 5.50 4.10 - Triphenylphosphine 0.15 0.15 0.15 Silica 81.00 85.00 87.60 Carbon black 0.35 0.35 0.35 γ-glycithoxypropyltrimethoxysilane 0.30 0.30 0.30 Laccarnauba Wax 0.10 0.10 0.10 Blood wax 0.10 0.10 0.10 Flame Retardant (UL94) V-0 V-1 V-0 CO ₂ laser marking color development usually usually Good definition Inadequate Inadequate Inadequate Cold shock evaluation (10% or more occurrence of package crack and chip peeling) After 100 cycles 0/100 0/100 0/100 After 200 cycles 12/100 0/100 0/100 After 300 cycles 58/100 16/100 0/100

[Property evaluation method]

* Flame retardant

: UL 94 vertical test and specimen thickness was based on 1/16 inch.

* Laser marking color development

: After marking the laser with a CO ₂ PLUS type laser, color development and clarity were evaluated.

* Cold Shock Test

: 100 ~ 200 and 300 cycles are severely tested for 10 minutes at high temperature (150 ℃) and low temperature (-65 ℃) with a Thermal Shock Tester, and package cracks and ultrasonic waves (C-SAM) are installed. The chip peeling state was observed.

As described in detail above, the epoxy resin composition for semiconductor element sealing of the present invention is not only excellent in flame retardancy and crack resistance, but also excellent in clarity of laser marking, and thus is useful for manufacturing a small and thin package of a surface mount method.

Claims (5)

(1) Ortho cresol novolac resin of the following formula (1), Diglycidyl hexamethyl biphenyl epoxy resin of formula Or 5.95-15.00 weight percent of these mixtures, (2) phenol novolac resin and cyclopentadiene resin of formula (3) Or 3.00-10.00 weight percent of these mixtures, (3) 0.10 to 0.30% by weight of a curing accelerator, (4) 0.05 to 0.40% by weight of potential curing catalyst, (5) inorganic filler 70.00-90.00% by weight, (6) 0.10 to 3.00 wt% of a diazo-based condensed pigment of the following formula (4) and (7) 0.80 to 1.50 wt% flame retardant Epoxy resin composition for sealing semiconductor elements comprising a. [Formula 1] (In the formula, G is a glycidyl group, R is a methyl group or a hydroxyl group, n is 0 to 5) [Formula 2] (Wherein R is a methyl group or a hydrogen group, n is 0-3) [Formula 3] (Wherein R is a methyl group or a hydrogen group, n is 0-4) [Formula 4] (Wherein R is a methyl group or a hydrogen group, R 'is a hydrogen group, a methyl group or a chlorine group, and M is an azo group) The method of claim 1, The epoxy resin composition for semiconductor element sealing, wherein the content of the diglycidyl hexamethyl biphenyl epoxy resin is 1.00 to 8.00 wt% based on the total composition. The method of claim 1, The curing accelerator is a tertiary amine compound, an organic phosphine compound or a mixture thereof; The latent curing catalyst is a triazine isocyanate imidazole compound, tetraphenylphosphonium tetraphenylborate, triphenylphosphine tetraphenylborate, or a mixture thereof; The inorganic filler is fused or synthetic silica having an average particle size of 0.1 to 35.0 μm; The flame retardant is an epoxy resin for sealing semiconductor elements, characterized in that the epoxy equivalent of 250 to 300 and a bromine content of 35 to 40% by weight of a mixture of 100 parts by weight of polyglycidyl ether brominated phenol epoxy and 20 to 40 parts by weight of antimony trioxide. Composition. The method of claim 1, An epoxy resin composition for semiconductor element sealing, further comprising an organic colorant, an inorganic colorant, or a mixture thereof as a colorant in addition to the diazo-based condensation dye. The method of claim 4, wherein Epoxy resin composition for semiconductor element sealing, characterized in that the diazo-based condensation pigment content in the colorant mixture is 20% by weight or more.