JP4984596B2 - Epoxy resin composition and semiconductor device - Google Patents

Description

  The present invention relates to an epoxy resin composition and a semiconductor device using the same, and in particular, an epoxy resin composition having excellent fluidity, releasability, and continuous moldability, and solder resistance using the same. The present invention relates to an excellent semiconductor device.

  In recent years, in the market trend of downsizing, weight reduction, and high performance of electronic devices, higher integration of semiconductors has progressed year by year, and surface mounting of semiconductor packages has been promoted. Furthermore, corporate activities that take the global environment into consideration are regarded as important, and lead, which is a hazardous substance, is required to be completely abolished by 2006 except for specific purposes. However, since the melting point of lead-free solder is higher than that of conventional lead / tin solder, the temperature at the time of solder mounting such as infrared reflow and solder immersion is increased from 220 to 240 ° C. to 240 to 260 ° C. Become. Due to such an increase in mounting temperature, there is a problem that cracks are likely to occur in the resin part during mounting, and it has become difficult to guarantee reliability. Further, with respect to the lead frame, from the viewpoint that it is necessary to remove lead from the external solder plating, the use of a lead frame that has been subjected to nickel / palladium plating in advance instead of the external solder plating is being promoted. This nickel / palladium plating has low adhesion to a general sealing material, and is likely to be peeled off at the interface during mounting, and cracks are likely to occur in the resin part.

For such a problem, by applying a low water-absorbing epoxy resin or a curing agent to improve solder heat resistance (for example, refer to Patent Documents 1, 2, and 3), the mounting temperature rises. The correspondence has come to come. On the other hand, the epoxy resin composition exhibiting such low water absorption and low elastic modulus has a low crosslinking density, and the molded product immediately after curing is soft, and in continuous production, there is a problem in moldability such as resin tray on the mold. There was a problem of lowering productivity.
In addition, as an effort to improve productivity, application of a release agent having a high release effect has been proposed (see, for example, Patent Document 4), but a release agent having a high release effect is inevitably formed. There is a drawback that the surface of the product is easily raised and the appearance of the molded product is remarkably soiled when continuously produced. In view of the above, there is a demand for an epoxy resin composition for semiconductor encapsulation that meets all the problems of solder heat resistance, mold release, continuous moldability, appearance of molded products, and mold contamination.

JP-A-9-3161 (pages 2 to 5) JP-A-9-235353 (pages 2-7) Japanese Patent Laid-Open No. 11-140277 (pages 2 to 11) JP 2002-80695 A (pages 2 to 5)

  The present invention has been made in view of the above circumstances, and its purpose is excellent in fluidity, releasability, and continuous moldability when molding and sealing, and low moisture absorption, low stress, and preprating. An object of the present invention is to provide an epoxy resin composition having characteristics excellent in adhesion to a frame and a semiconductor device excellent in solder resistance using the same.

The present invention
[1] In an epoxy resin composition mainly comprising (A) an epoxy resin , (B) a phenol resin curing agent, (C) a curing accelerator, and (D) an inorganic filler, the (A) epoxy resin is Resin represented by the general formula (1) (in the general formula (1), X is a glycidyl ether group), and the (B) phenol resin-based curing agent is a resin represented by the general formula (1) (general formula (1) X is a hydroxyl group), and (E) an oxidized polyethylene wax is contained in the total epoxy resin composition in a proportion of 0.01% by weight to 1% by weight, and (F) a butadiene-acrylonitrile copolymer having a carboxyl group. The reaction product (f2) of the polymer (f1) and / or the butadiene-acrylonitrile copolymer having a carboxyl group and the epoxy resin is added to the total epoxy resin composition by 0.01 weight. In a proportion of not less than 1% by weight
The oxidized polyethylene wax has a dropping point of 100 ° C. or more and 140 ° C. or less, an average particle size of 20 μm or more and 70 μm or less, and a content ratio of particles having a particle size of 106 μm or more in the total oxidized polyethylene wax is 0.1. or less by weight%, acid value 10 mgKOH / g or more and less 50 mg KOH / g, number average molecular weight of 500 or more and 5000 or less, a density of 0.94 g / cm ³ or more, 1.03 g / cm ³ or less The oxidized polyethylene wax is at least one selected from an oxide of polyethylene wax produced by a low pressure polymerization method, an oxide of polyethylene wax produced by a high pressure polymerization method, and an oxide of a high density polyethylene polymer. ,
The epoxy resin composition for semiconductor encapsulation, wherein the butadiene-acrylonitrile copolymer (f1) having a carboxyl group is represented by the general formula (4):

（ただし、上記一般式（１）において、Ｒは水素原子又は炭素数１〜４のアルキル基から選択される基であり、互いに同一であっても、異なっていてもよい。Ｘはグリシジルエーテル基又は水酸基。ｎは平均値で、１〜３の正数。）

（ただし、上記一般式（４）において、ｘは１未満の正数。ｙは１未満の正数。ｘ＋ｙ＝１。ｚは５０〜８０の整数。）

(In the general formula (1), R is a group selected from a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. X is a glycidyl ether group. Or a hydroxyl group, where n is an average value and is a positive number of 1 to 3.)

(However, in the general formula (4), x is a positive number less than 1. y is a positive number less than 1. x + y = 1. Z is an integer of 50 to 80.)

[ 2 ] A semiconductor device comprising a semiconductor element sealed with the epoxy resin composition according to item [1] ,
It is.

  According to the present invention, a resin composition having excellent releasability when molding and sealing a semiconductor element, continuous moldability, and low moisture absorption, low stress, and excellent adhesion to a preplating frame. Can be obtained. Further, according to the present invention, a semiconductor device having excellent solder resistance and reliability after soldering can be obtained with high productivity.

The present invention relates to an epoxy resin composition comprising (A) an epoxy resin, (B) a phenol resin-based curing agent, (C) a curing accelerator, and (D) an inorganic filler as a main component. And (B) any of the phenolic resin-based curing agents includes a novolak resin having a biphenylene skeleton in the main chain, (E) a specific amount of oxidized polyethylene wax, and (F) a butadiene-acrylonitrile copolymer. By including a specific amount of the reaction product (f2) of (f1) and / or a butadiene / acrylonitrile copolymer having a carboxyl group and an epoxy resin, it is excellent in releasability when molding and sealing, continuous moldability, In addition, an epoxy resin composition for semiconductor encapsulation that is low in stress and excellent in solder resistance can be obtained.
Hereinafter, the present invention will be described in detail.

  The epoxy resin represented by the general formula (1) used as the epoxy resin (A) in the present invention (X is a glycidyl ether group) contains a lot of hydrophobic structures in the resin skeleton. Since the cured product of the composition has a low moisture absorption rate and a low crosslink density, it has a characteristic that its elastic modulus is small in a high temperature region above the glass transition temperature. The cured resin of the epoxy resin composition using this has low hygroscopicity, and can reduce explosive stress due to vaporization of water during soldering. In addition, since it has a low elastic modulus when heated, the thermal stress generated during the soldering process is reduced, resulting in excellent solder resistance.

  In the range which does not impair the effect by using the epoxy resin (X is a glycidyl ether group) shown by General formula (1) used by this invention, it can use together with another epoxy resin. Other epoxy resins used in combination include, for example, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, bisphenol type epoxy resin, stilbene type epoxy resin, triphenolmethane type epoxy resin, phenol aralkyl (phenylene) (Including skeleton) type epoxy resin, naphthol type epoxy resin, alkyl-modified triphenol methane type epoxy resin, triazine nucleus-containing epoxy resin, dicyclopentadiene-modified phenol type epoxy resin, etc. These may be used alone or in combination. Good. Although the specific example of the epoxy resin (X is a glycidyl ether group) shown by General formula (1) is shown in Formula (2), it is not limited to these.

（ただし、上記式（２）において、ｎは平均値で１〜３の正数。）

(However, in the above formula (2), n is an average value and a positive number of 1 to 3.)

  The phenol resin represented by the general formula (1) used as the phenol resin-based curing agent (B) in the present invention (X is a hydroxyl group) contains a lot of hydrophobic structures in the resin skeleton. Since the cured product of the resin composition has a low moisture absorption rate and a low crosslinking density, it has a characteristic that the elastic modulus in a high temperature region above the glass transition temperature is small. The resin cured product of the epoxy resin composition using this exhibits a low moisture absorption rate, and can reduce explosive stress due to vaporization of moisture during soldering. In addition, since it has a low elastic modulus when heated, the thermal stress generated during the soldering process is reduced, resulting in excellent solder resistance.

  In the range which does not impair the effect by using the phenol resin (X is a hydroxyl group) shown by General formula (1) used by this invention, it can use together with another phenol resin hardening | curing agent. Examples of other phenol resin curing agents used in combination include, for example, phenol novolac resin, cresol novolac resin, triphenolmethane resin, terpene modified phenol resin, dicyclopentadiene modified phenol resin, phenol aralkyl resin (including phenylene skeleton), There are naphthol aralkyl resins and the like, and these may be used alone or in combination. Although the specific example of the phenol resin (X is a hydroxyl group) which has general formula (1) as a basic skeleton is shown in Formula (3), it is not limited to these.

（ただし、上記式（３）において、ｎは平均値で１〜３の正数。）

(However, in said Formula (3), n is an average value and a positive number of 1-3.)

  The equivalent ratio of the epoxy groups of all epoxy resins and the phenolic hydroxyl groups of all phenolic resin-based curing agents used in the present invention is preferably 0.5 or more and 2 or less, particularly preferably 0.7 or more. 5 or less. When it is within the above range, it is possible to suppress a decrease in moisture resistance, curability and the like.

  The curing accelerator (C) used in the present invention refers to one that can be a catalyst for a crosslinking reaction between an epoxy resin and a phenol resin-based curing agent. For example, tributylamine, 1,8-diazabicyclo (5,4,0) Examples include, but are not limited to, amine compounds such as undecene-7, organic phosphorus compounds such as triphenylphosphine and tetraphenylphosphonium / tetraphenylborate salts, and imidazole compounds such as 2-methylimidazole. . These curing accelerators may be used alone or in combination.

  Examples of the inorganic filler (D) used in the present invention include fused silica, crystalline silica, alumina, silicon nitride, and aluminum nitride. When the amount of the inorganic filler is particularly large, it is common to use fused silica. Fused silica can be used in either crushed or spherical shape, but in order to increase the blending amount of fused silica and to suppress the increase in melt viscosity of the epoxy resin composition, it is preferable to mainly use a spherical one. . In order to further increase the blending amount of the spherical silica, it is desirable to adjust so that the particle size distribution of the spherical silica becomes wider.

The oxidized polyethylene wax (E) used in the present invention generally has a polar group composed of a carboxylic acid or the like and a nonpolar group composed of a long carbon chain, so that the polar group is oriented on the resin cured product side during molding. On the other hand, the nonpolar group functions as a release agent by being oriented on the mold side. The dropping point of the oxidized polyethylene wax used in the present invention is preferably 100 ° C. or higher and 140 ° C. or lower, more preferably 110 ° C. or higher and 130 ° C. or lower. If it is less than the lower limit, thermal stability is not sufficient, and seizure of oxidized polyethylene wax occurs during continuous molding, which may deteriorate mold release properties and impair continuous moldability. When the upper limit is exceeded, when the epoxy resin composition is cured, the oxidized polyethylene wax is not sufficiently melted, so that the dispersibility of the oxidized polyethylene wax is reduced. There is a risk of deteriorating the appearance of the cured resin. The acid value is preferably 10 mgKOH / g or more and 50 mgKOH / g or less, more preferably 15 mgKOH / g or more and 40 mgKOH / g or less. The acid value affects the compatibility with the cured resin. If the acid value is less than the lower limit, the oxidized polyethylene wax causes phase separation from the epoxy resin matrix, which may cause mold contamination and deterioration of the appearance of the cured resin. If the upper limit is exceeded, the compatibility with the epoxy resin matrix is too good, so that it cannot ooze out on the surface of the cured product and there is a possibility that sufficient releasability cannot be ensured. The number average molecular weight is preferably 500 or more and 5000 or less, more preferably 1000 or more and 4000 or less. If the number average molecular weight is less than the lower limit, the oxidized polyethylene wax has an increased affinity with the epoxy resin matrix, and there is a possibility that sufficient releasability cannot be obtained. When the upper limit is exceeded, phase separation occurs, which may cause mold contamination and deterioration of the appearance of the cured resin. The density is preferably 0.94 g / cm ³ or more and 1.03 g / cm ³ or less, more preferably 0.97 g / cm ³ or more and 0.99 g / cm ³ or less. If it is less than the lower limit, thermal stability is not sufficient, and seizure of oxidized polyethylene wax occurs during continuous molding, which may deteriorate mold release properties and impair continuous moldability. When the upper limit is exceeded, when the epoxy resin composition is cured, the oxidized polyethylene wax is not sufficiently melted, so that the dispersibility of the oxidized polyethylene wax is reduced. There is a risk of deteriorating the appearance of the cured resin. The average particle size is preferably 20 μm or more and 70 μm or less, more preferably 30 μm or more and 60 μm or less. If it is less than the lower limit value, the polyethylene oxide wax is too compatible with the epoxy resin matrix, so that it cannot ooze out on the surface of the cured product and there is a possibility that a sufficient release imparting effect cannot be obtained. When the upper limit is exceeded, the oxidized polyethylene wax is segregated, which may cause mold stains and deterioration of the appearance of the cured resin. In addition, when the epoxy resin composition is cured, the polyethylene oxide wax is not sufficiently melted, which may hinder fluidity. The content ratio of particles having a particle size of 106 μm or more in the total oxidized polyethylene wax is preferably 0.1% by weight or less. When the upper limit is exceeded, the oxidized polyethylene wax is segregated, which may cause mold stains and deterioration of the appearance of the cured resin. In addition, when the epoxy resin composition is cured, the polyethylene oxide wax is not sufficiently melted, which may hinder fluidity. The content of the oxidized polyethylene wax is 0.01% by weight or more and 1% by weight or less, and preferably 0.03% by weight or more and 0.5% by weight or less in the epoxy resin composition. If it is less than the lower limit value, the releasability becomes insufficient, and if it exceeds the upper limit value, the adhesion with the lead frame member is impaired, and there is a possibility that peeling from the member occurs during the soldering process. Moreover, there exists a possibility of causing deterioration of mold | die stain | pollution | contamination and resin hardened | cured material external appearance.

The oxidized polyethylene wax used in the present invention is commercially available, and can be used after adjusting the particle size.
The polyethylene oxide wax used in the present invention is preferably an oxide of polyethylene wax produced by a low pressure polymerization method, an oxide of polyethylene wax produced by a high pressure polymerization method, or an oxide of a high density polyethylene polymer.
Other release agents may be used in combination as long as the effects of using the oxidized polyethylene wax used in the present invention are not impaired. Examples of release agents that can be used in combination include natural waxes such as carnauba wax, and metal salts of higher fatty acids such as zinc stearate.

In the present invention, (F) a butadiene / acrylonitrile copolymer (f1) having a carboxyl group and / or a reaction product (f2) of a butadiene / acrylonitrile copolymer having a carboxyl group and an epoxy resin is used as the total epoxy resin composition. It is essential that it is contained in the product at a ratio of 0.01% by weight or more and 1% by weight or less. The carboxyl group-containing butadiene-acrylonitrile copolymer (f1) is a copolymer of butadiene and acrylonitrile, and the reaction product (f2) of (f1) and (f1) with an epoxy resin is blended in the resin composition. As a result, not only excellent crack resistance can be obtained, but also the feature of improving the releasability can be obtained.
The butadiene-acrylonitrile copolymer (f1) having a carboxyl group is not particularly limited, but a compound having a carboxyl group at both ends of the structure is preferable, and a compound represented by the general formula (4) is more preferable. preferable. Since this carboxyl group has polarity, the dispersibility of the butadiene / acrylonitrile copolymer in the epoxy resin contained as the raw material of the epoxy resin composition for sealing becomes good, and the mold surface becomes dirty or molded. The progress of surface contamination can be suppressed, and the continuous moldability can be improved. In general formula (4), x is a positive number less than 1, y is a positive number less than 1, x + y = 1, and z is an integer of 50 to 80. In addition, the resin composition of the present invention was previously melted and reacted with an epoxy resin and a curing accelerator in advance, as the component (F), all or part of the butadiene-acrylonitrile copolymer (f1) having a carboxyl group. The reaction product (f2) can also be used. The curing accelerator referred to here may be any accelerator that accelerates the curing reaction between the carboxyl group in the butadiene / acrylonitrile copolymer and the epoxy group in the epoxy resin, and the curing of the epoxy group and the phenolic hydroxyl group described above. The same curing accelerator that promotes the reaction can be used. The blending amount of the component (F) used in the present invention is essential to be 0.01% by weight or more and 1% by weight or less in the total epoxy resin composition, preferably 0.05 or more and 0.5% by weight or less, More preferably, it is 0.1 to 0.3% by weight. By setting it as the said range, generation | occurrence | production of malfunctions, such as generation | occurrence | production of the filling failure at the time of shaping | molding by the fall of fluidity | liquidity, and gold wire deformation | transformation by high viscosity can be suppressed.

（ただし、上記一般式（４）において、ｘは１未満の正数。ｙは１未満の正数。ｘ＋ｙ＝１。ｚは５０〜８０の整数。）

(However, in the general formula (4), x is a positive number less than 1. y is a positive number less than 1. x + y = 1. Z is an integer of 50 to 80.)

The acrylonitrile content y in the butadiene-acrylonitrile copolymer having a carboxyl group used in the present invention is preferably 0.05 or more and 0.30 or less, more preferably 0.10 or more and 0.25 or less. The acrylonitrile content y affects the compatibility with the epoxy resin matrix. If the acrylonitrile content is less than the lower limit, the carboxyl-terminated butadiene / acrylonitrile copolymer causes phase separation from the epoxy resin matrix, resulting in deterioration of mold stains and resin cured product appearance. May cause. If the upper limit is exceeded, fluidity may be reduced, resulting in poor filling during molding or inconveniences such as deformation of the gold wire in the semiconductor device due to increased viscosity.
The number average molecular weight of the butadiene-acrylonitrile copolymer having a carboxyl group used in the present invention is preferably from 2,000 to 5,000, more preferably from 3,000 to 4,000. By setting it as the said range, generation | occurrence | production of malfunctions, such as generation | occurrence | production of the filling failure at the time of shaping | molding by the fall of fluidity | liquidity, and gold wire deformation | transformation by high viscosity can be suppressed.
The carboxyl group equivalent of the butadiene-acrylonitrile copolymer having a carboxyl group used in the present invention is preferably 1200 or more and 3000 or less, more preferably 1700 or more and 2500 or less. By making it within the above range, the mold and molded product are less likely to be stained without lowering the fluidity and releasability at the time of molding the resin composition, and the effect that the continuous moldability is particularly good is obtained. It is done.

The epoxy resin composition of the present invention comprises the components (A) to (F) as essential components, but it is difficult to use brominated epoxy resins, antimony trioxide, phosphorus compounds, metal hydroxides, etc. as necessary. Flame retardants, coupling agents such as γ-glycidoxypropyltrimethoxysilane, colorants such as carbon black and bengara, low stress agents such as silicone oil, silicone rubber and synthetic rubber, and antioxidants such as bismuth oxide hydrate You may mix | blend various additives, such as these suitably. Furthermore, if necessary, the inorganic filler may be used after being previously treated with a coupling agent, an epoxy resin, or a phenol resin curing agent. The treatment method is a method of removing the solvent after mixing with a solvent. Alternatively, there is a method of adding directly to the inorganic filler and processing using a mixer.
In the epoxy resin composition of the present invention, the components (A) to (F) and other additives are mixed using a mixer and the like, then heated and kneaded using a heating kneader, a hot roll, an extruder, etc. Obtained by cooling and grinding.
In order to seal an electronic component such as a semiconductor element by using the epoxy resin composition of the present invention and manufacture a semiconductor device, it may be cured by a conventional molding method such as transfer molding, compression molding, injection molding, or the like. .

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these. The blending ratio is parts by weight.
Reference example 1

Epoxy resin of formula (2) (phenol aralkyl type epoxy resin having a biphenylene skeleton) [manufactured by Nippon Kayaku, NC3000P, softening point 58 ° C., epoxy equivalent 273]
7.45 parts by weight

Phenol resin of formula (5) (phenol aralkyl resin having a phenylene skeleton [Mitsui Chemicals, XLC-4L, softening point 65 ° C., hydroxyl equivalent 174]
4.75 parts by weight

1,8-diazabicyclo (5,4,0) undecene-7 (hereinafter referred to as “DBU”)
0.20 parts by weight Spherical fused silica (average particle size 30.0 μm) 87.00 parts by weight Oxidized polyethylene wax 1 (drop point 120 ° C., acid value 20 mg KOH / g, number average molecular weight 2000, density 0.98 g / cm ³ , (Average particle diameter 45 μm, particle diameter 106 μm or more, 0.0% by weight, high density polyethylene polymer oxide) 0.10 parts by weight

Butadiene / acrylonitrile copolymer 1 of formula (4) (manufactured by Ube Industries, Ltd., HYCAR CTBN 1008-SP, x = 0.82, y = 0.18, z average value is 62, number average molecular weight 3550, Carboxyl group equivalent 2200 g / eq) 0.20 parts by weight

After mixing 0.30 parts by weight of carbon black using a mixer, the mixture was kneaded 20 times using a biaxial roll having surface temperatures of 95 ° C. and 25 ° C., and the resulting kneaded material sheet was cooled and pulverized to obtain an epoxy. A resin composition was obtained. The characteristics of the obtained epoxy resin composition were evaluated by the following methods.

Evaluation method Spiral flow: Using a low-pressure transfer molding machine, a spiral flow measurement mold conforming to EMMI-1-66, epoxy resin under conditions of a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 120 seconds The composition was injected and the flow length was measured. The unit is cm.

  Deformation rate of gold wire: 160pLQFP (preprating frame, nickel-palladium alloy gold-plated, package outer dimensions, using a low-pressure transfer automatic molding machine, mold temperature 175 ° C, injection pressure 9.6 MPa, curing time 70 seconds : 24 mm × 24 mm × 1.4 mm thickness, pad size: 8.5 mm × 8.5 mm, chip size 7.4 mm × 7.4 mm). The molded 160 pLQFP package was observed with a soft X-ray fluoroscope, and the deformation rate of the gold wire was expressed as a ratio of (flow rate) / (gold wire length). The criterion was ○ for less than 5% and x for 5% or more.

  Continuous formability: 80pQFP (preprating frame, nickel / palladium alloy gold-plated, package outer dimensions: mold temperature 175 ° C., injection pressure 9.6 MPa, curing time 70 seconds, using automatic low-pressure molding machine 14 mm × 20 mm × 2 mm thickness, pad size: 6.5 mm × 6.5 mm, chip size 6.0 mm × 6.0 mm) were continuously molded up to 500 shots. As the judgment criteria, a case where continuous molding was performed up to 500 shots without any problems such as unfilling occurred was marked with ◯, and other cases were marked with x.

  Molded product appearance and mold stain: In the evaluation of the continuous moldability, the package and mold after 500 shots were visually evaluated for stain. The package appearance judgment and the mold contamination standard are indicated by “x” when dirty and by “◯” when not dirty up to 500 shots.

  Solder resistance: The package molded in the evaluation of the above-described continuous formability is post-cured at 175 ° C. for 8 hours, and the resulting package is humidified at 85 ° C. and 60% relative humidity for 168 hours, and then placed in a solder bath at 260 ° C. The package was immersed for 10 seconds. The adhesion state of the interface between the 20 semiconductor elements immersed in the solder and the epoxy resin composition is observed with an ultrasonic flaw detector, and the occurrence rate of peeling [(number of peeling occurrence packages) / (total number of packages) × 100] is calculated. did. Units%. The criteria for determining solder resistance were ◯ when no peeling occurred, Δ when the peeling rate was less than 20%, and x when the peeling rate was 20% or more.

Reference Example 2, Examples 3 to 19, Comparative Examples 1 to 7
Table 1, Table 2, blended components in the proportions shown in Table 3, to obtain an epoxy resin composition in the same manner as in Reference Example 1, was evaluated in the same manner as in Reference Example 1. The results are shown in Table 1, Table 2, and Table 3.
The components used in other than Reference Example 1 are shown below.

Epoxy resin of formula (6) (biphenyl type epoxy resin) [manufactured by Jaban Epoxy Resin Co., Ltd., YX-4000H, melting point 105 ° C., epoxy equivalent 191]

Phenol resin of formula (3) (phenol aralkyl resin having a biphenylene skeleton) [Maywa Kasei Co., Ltd., MEH7851SS, softening point 67 ° C., hydroxyl group equivalent 203]

Oxidized polyethylene wax 2 (drop point 105 ° C., acid value 20 mg KOH / g, number average molecular weight 1100, density 0.97 g / cm ³ , average particle size 45 μm, particle size 106 μm or more, 0.0% by weight, by low pressure polymerization method) Manufactured polyethylene wax oxide)
Oxidized polyethylene wax 3 (drop point 135 ° C., acid value 25 mg KOH / g, number average molecular weight 3000, density 0.99 g / cm ³ , average particle size 40 μm, particle size 106 μm or more, 0.0% by weight, high density polyethylene polymer Oxide)
Oxidized polyethylene wax 4 (drop point 110 ° C., acid value 12 mg KOH / g, number average molecular weight 1200, density 0.97 g / cm ³ , average particle size 50 μm, particle size 106 μm or more, 0.0% by weight, high density polyethylene polymer Oxide)
Oxidized polyethylene wax 5 (drop point 110 ° C., acid value 45 mg KOH / g, number average molecular weight 2000, density 0.97 g / cm ³ , average particle size 45 μm, particle size 106 μm or more, 0.0% by weight, by high pressure polymerization method Manufactured polyethylene wax oxide)
Oxidized polyethylene wax 6 (drop point 110 ° C., acid value 20 mg KOH / g, number average molecular weight 750, density 0.98 g / cm ³ , average particle size 45 μm, particle size 106 μm or more, 0.0% by weight, high density polyethylene polymer Oxide)
Oxidized polyethylene wax 7 (drop point 130 ° C., acid value 20 mg KOH / g, number average molecular weight 4500, density 0.99 g / cm ³ , average particle diameter 45 μm, particle diameter 106 μm or more, 0.0% by weight, by high pressure polymerization method) Manufactured polyethylene wax oxide)
Oxidized polyethylene wax 8 (drop point 110 ° C., acid value 20 mg KOH / g, number average molecular weight 1100, density 0.95 g / cm ³ , average particle size 45 μm, particle size 106 μm or more, 0.0% by weight, by low pressure polymerization method) Manufactured polyethylene wax oxide)
Oxidized polyethylene wax 9 (drop point 110 ° C., acid value 25 mg KOH / g, number average molecular weight 2000, density 1.02 g / cm ³ , average particle size 45 μm, particle size 106 μm or more, 0.0% by weight, high density polyethylene polymer Oxide)
Oxidized polyethylene wax 10 (drop point 120 ° C., acid value 20 mgKOH / g, number average molecular weight 2000, density 0.98 g / cm ³ , average particle size 30 μm, particle size 106 μm or more, 0.0% by weight, high density polyethylene polymer Oxide)
Oxidized polyethylene wax 11 (drop point 120 ° C., acid value 20 mg KOH / g, number average molecular weight 2000, density 0.98 g / cm ³ , average particle size 60 μm, particle size 106 μm or more 0.0% by weight, high density polyethylene polymer Oxide)

Polyethylene wax 1 (drop point 135 ° C., acid value 0 mg KOH / g, number average molecular weight 5500, density 0.93 g / cm ³ , average particle size 45 μm, particle size 106 μm or more 0.0% by weight, manufactured by low pressure polymerization method Polyethylene wax)
Polyethylene wax 2 (drop point 115 ° C., acid value 0 mg KOH / g, number average molecular weight 1800, density 0.93 g / cm ³ , average particle size 45 μm, particle size 106 μm or more 0.0% by weight, manufactured by high pressure polymerization method Polyethylene wax)

溶融反応物Ａ：ビスフェノールＡ型エポキシ樹脂（ジャパンエポキシレジン製、ＹＬ−６８１０、エポキシ当量１７０ｇ／ｅｑ、融点４７℃）６６．１重量部を１４０℃で加温溶融し、ブタジエン・アクリロニトリル共重合体１（宇部興産（株）製、ＨＹＣＡＲ ＣＴＢＮ １００８−ＳＰ、ｘ＝０．８２、ｙ＝０．１８、ｚの平均値は６２、数平均分子量３５５０、カルボキシル基当量２２００ｇ／ｅｑ）３３．１重量部及びトリフェニルホスフィン０．８重量部を添加して、３０分間溶融混合して溶融反応物Ａを得た。 Butadiene / acrylonitrile copolymer 2 of formula (4) (manufactured by Ube Industries, Ltd., HYCAR CTBN 1008 × 13, x = 0.74, y = 0.26, z has an average value of 54, a number average molecular weight of 3150, Carboxyl group equivalent 2000 g / eq)

Molten reaction product A: bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin, YL-6810, epoxy equivalent 170 g / eq, melting point 47 ° C.) 66.1 parts by weight was heated and melted at 140 ° C. to obtain a butadiene / acrylonitrile copolymer 1 (Ube Industries, Ltd., HYCAR CTBN 1008-SP, x = 0.82, y = 0.18, z has an average value of 62, number average molecular weight 3550, carboxyl group equivalent 2200 g / eq) 33.1 weight And 0.8 part by weight of triphenylphosphine were added and melt mixed for 30 minutes to obtain a molten reactant A.

Examples 3 to 19 all had good fluidity, releasability, continuous formability, and solder resistance. In Comparative Example 1 in which the resin represented by the general formula (1) was not used, the low moisture absorption effect and the low stress reduction effect at high temperature were not exhibited, resulting in poor solder resistance. Moreover, in Comparative Examples 2 and 3 in which the oxidized polyethylene wax (E) was not used, the continuous moldability deteriorated, and the molded product appearance, mold contamination, and solder resistance were inferior. In Comparative Example 4 in which the blending amount of the oxidized polyethylene wax (E) is insufficient, the releasability is lowered, resulting in poor continuous moldability and solder resistance. In Comparative Example 5 in which the blending amount of the oxidized polyethylene wax (E) is excessive, the excess component bleeds to the interface with the member and the surface of the cured product, so that the mold contamination and the appearance of the molded product are deteriorated, and the solder resistance is also improved. The result was inferior. In Comparative Example 6 where (F) a butadiene-acrylonitrile copolymer having a carboxyl group (f1) and / or a reaction product (f2) of a butadiene-acrylonitrile copolymer having a carboxyl group and an epoxy resin is not used, As a result of the releasability, the continuous formability and solder resistance were inferior. In Comparative Example 7 in which the compounding amount of the butadiene-acrylonitrile copolymer (f1) having a carboxyl group is excessive, the deformation rate of the gold wire is deteriorated and the solder resistance is also inferior due to the decrease in the fluidity of the resin composition. As a result. From the above, it has been found that by using the epoxy resin composition of the present invention, a semiconductor device package having an excellent balance of fluidity, releasability, continuous formability and solder resistance can be provided.

  The epoxy resin composition of the present invention has excellent properties such as low moisture absorption and low stress, and is excellent in releasability and continuous moldability when molding and sealing a semiconductor element using the epoxy resin composition. Excellent adhesion to frames, especially plated copper lead frames (silver-plated lead frames, nickel-plated lead frames, nickel-palladium alloy gold-plated pre-plating frames, etc.) and solder resistance Therefore, it can be suitably used for a semiconductor device that is surface-mounted using lead-free solder.

Claims (2)

In the epoxy resin composition having (A) an epoxy resin, (B) a phenol resin-based curing agent, (C) a curing accelerator, and (D) an inorganic filler as a main component, the (A) epoxy resin is represented by the general formula ( 1) (in general formula (1), X is a glycidyl ether group), and the (B) phenol resin curing agent is represented by general formula (1) (in general formula (1), X is A hydroxyl group), (E) a butadiene-acrylonitrile copolymer having (E) an oxidized polyethylene wax in a proportion of not less than 0.01% by weight and not more than 1% by weight in the total epoxy resin composition and having a carboxyl group (F) f1) and / or a reaction product (f2) of a butadiene-acrylonitrile copolymer having a carboxyl group and an epoxy resin in a total epoxy resin composition of 0.01% by weight or less. Wherein a proportion of 1 wt% or less,
The oxidized polyethylene wax has a dropping point of 100 ° C. or more and 140 ° C. or less, an average particle size of 20 μm or more and 70 μm or less, and a content ratio of particles having a particle size of 106 μm or more in the total oxidized polyethylene wax is 0.1. or less by weight%, acid value 10 mgKOH / g or more and less 50 mg KOH / g, number average molecular weight of 500 or more and 5000 or less, a density of 0.94 g / cm ³ or more, 1.03 g / cm ³ or less The oxidized polyethylene wax is at least one selected from an oxide of polyethylene wax produced by a low pressure polymerization method, an oxide of polyethylene wax produced by a high pressure polymerization method, and an oxide of a high density polyethylene polymer. ,
The epoxy resin composition for semiconductor encapsulation, wherein the butadiene-acrylonitrile copolymer (f1) having a carboxyl group is represented by the general formula (4).

(In the general formula (1), R is a group selected from a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. X is a glycidyl ether group. Or a hydroxyl group, where n is an average value and is a positive number of 1 to 3.)

(However, in the general formula (4), x is a positive number less than 1. y is a positive number less than 1. x + y = 1. Z is an integer of 50 to 80.) A semiconductor device comprising a semiconductor element sealed using the epoxy resin composition according to claim 1.