JP6789030B2 - Encapsulating resin composition and semiconductor device - Google Patents

Description

The present invention relates to a resin composition used as a sealing material for electronic parts such as semiconductors, and a semiconductor device using the resin composition.

As a sealing material in semiconductor devices such as transistors, integrated circuits (ICs), and large-scale integrated circuits (LSIs), epoxy resin is used as a base, and curing agents, curing accelerators, and inorganic fillers such as silica powder are used. Resin compositions containing colorants and the like are widely used. This is because the epoxy resin composition is excellent in electrical properties, heat resistance, moisture resistance, and mechanical properties, and has a balance between productivity and cost.

However, in recent years, in order to meet the market demands for miniaturization, weight reduction, and high performance of electronic devices, high integration of semiconductor elements and surface mounting of semiconductor devices have progressed, and along with this, they are used for sealing semiconductor elements. The demand for epoxy resin compositions is becoming more and more stringent.

In particular, in surface-mounted semiconductor devices, the semiconductor device is exposed to high temperatures during solder reflow, causing peeling at the interface between the semiconductor element or lead frame and the cured product of the epoxy resin composition, which in turn causes cracks in the semiconductor device. Etc., defects that greatly impair reliability may occur. Therefore, prevention of these defects, that is, improvement of reflow resistance has become a major issue.

To solve this problem, it has been studied to use a resin having low elasticity and low moisture absorption. This is because the stress generated at the interface between the semiconductor element or lead frame and the cured product of the epoxy resin composition during reflow can be relaxed due to the low elasticity, and the absorption of water into the encapsulant due to the low moisture absorption. This is because the peeling caused by the vaporization and expansion of water can be reduced.

On the other hand, semiconductor devices mounted on in-vehicle electronic devices and the like are required to have operational reliability in a harsher environment than personal computers and home appliances, for example, at a high temperature of 150 ° C. or higher. Further, in recent semiconductor devices using silicon carbide (SiC) devices, the operating temperature is said to reach 200 ° C. or higher. Therefore, the semiconductor encapsulant used in these applications is required to have high heat resistance.

In an epoxy resin composition, particularly a composition in which an epoxy resin and a phenol curing agent are combined, it is effective to increase the crosslink density and obtain a high glass transition temperature (Tg) in order to increase the heat resistance. However, when the crosslink density is increased, the cured product generally becomes a rigid structure and tends to have high elasticity. In addition, since the cross-linking points are structurally polarized, the hygroscopicity is also high.

As described above, there is a demand for an epoxy resin composition having excellent reflow resistance and heat resistance, but it is very difficult to achieve both of these. Under such circumstances, a composition in which a benzoxazine resin known as a highly heat-resistant resin is combined with an epoxy resin has been reported (see, for example, Patent Documents 1 and 2). In this composition, a benzoxazine resin and an epoxy resin react to obtain a dense crosslinked structure, which can have a Tg of more than 200 ° C., and the benzoxazine resin relaxes the polarization of the crosslinked point due to the structure. , Hygroscopicity is also low.

However, the cured product still has high elasticity, and there is still room for improvement in terms of reflow resistance in order to use it as a sealing material. Further, since the reaction rate of the cross-linking reaction between the benzoxazine resin and the epoxy resin is slow, there is also a problem that curing failure occurs under general encapsulant molding conditions.

JP-A-2010-254895 Japanese Unexamined Patent Publication No. 2011-231196

The present invention has been made to solve the above problems, and is sealed by a sealing resin composition having good reflow resistance and heat resistance and also excellent moldability, and such a composition. An object of the present invention is to provide a highly reliable semiconductor device.

The sealing resin composition of the present invention comprises (A) an epoxy resin, (B) a bismaleimide resin having an aliphatic hydrocarbon group in the main chain having a predetermined structure, (C) a phenol curing agent, and (D) curing. A resin composition containing an accelerator and (E) an inorganic filler, wherein the compounding ratio (A): (B) of (A) epoxy resin and (B) bismaleimide resin is 95: 5 to 50: by mass ratio. It is 50, and the content of the (E) inorganic filler is 70 to 95% by mass of the entire composition.

The semiconductor device of the present invention is characterized in that the electronic component is sealed by a cured product of the resin composition for sealing the electronic component of the present invention.

According to the resin composition for encapsulating electronic components and the semiconductor device of the present invention, the obtained cured product has good reflow resistance and heat resistance, and is also excellent in moldability, so that a highly reliable semiconductor device can be obtained. Can be done.

As described above, the sealing resin composition of the present invention comprises (A) an epoxy resin, (B) a bismaleimide resin having an aliphatic hydrocarbon group in the main chain, (C) a phenol curing agent, and (D) promoting curing. A resin composition containing an agent and (E) an inorganic filler. Hereinafter, each component constituting this sealing resin composition will be described in detail.

In the sealing resin composition of the present invention, as long as the epoxy resin (A) has two or more epoxy groups in one molecule, its molecular weight, molecular structure, and the like are not particularly limited. Specifically, for example, crystalline epoxy resins such as biphenyl aralkyl type epoxy resin, biphenyl type epoxy resin, bisphenol type epoxy resin, and stillben type epoxy resin; novolak type epoxy such as phenol novolac type epoxy resin and cresol novolac type epoxy resin. Resin: Polyfunctional epoxy resin such as triphenol methane type epoxy resin and alkyl-modified triphenol methane type epoxy resin; Phenol aralkyl type epoxy resin having a phenylene skeleton; Dihydroxynaphthalene type epoxy resin and dihydroxynaphthalene dimer are converted into glycidyl ether. Naftor type epoxy resin such as the epoxy resin obtained in the above; Triazine nucleus-containing epoxy resin such as triglycidyl isocyanurate and monoallyl glycidyl isocyanurate; Arashi bridge cyclic hydrocarbon compound modified phenol type such as dicyclopentadiene modified phenol type epoxy resin Epoxy resin and the like can be mentioned. One type of these epoxy resins may be used alone, or two or more types may be used in combination.

As the epoxy resin (A), a biphenyl type epoxy resin and a biphenyl aralkyl type epoxy resin are preferable, and a biphenyl aralkyl type epoxy resin is particularly preferable.

In the sealing resin composition of the present invention, the component (B) is a bismaleimide resin having an aliphatic hydrocarbon group in the main chain, and the main chain connecting the two maleimide groups has one or more carbon atoms. It is composed of an aliphatic hydrocarbon group. Here, the aliphatic hydrocarbon group may be in any form of linear, branched or cyclic, preferably having 6 or more carbon atoms, and more preferably 12 or more carbon atoms. It is particularly preferable that the number of carbon atoms is 24 or more. Further, it is preferable that this aliphatic hydrocarbon group is directly bonded to the maleimide group.

By containing such a bismaleimide resin, a sealing resin composition having excellent heat resistance, low stress and good reflow resistance can be obtained.

（式中、ｎは１〜１０の整数である。） As the component (B), an imide-extended bismaleimide compound (B1) represented by the following general formula (1) is preferably mentioned.

(In the formula, n is an integer of 1 to 10.)

Examples of the bismaleimide compound (B1) include BMI-3000 (manufactured by Digigner Moleculars, trade name; molecular weight 3000), BMI-5000 (manufactured by Digigner Moleculars, trade name; molecular weight 5000), and the like. And so on.

The polystyrene-equivalent number average molecular weight of the bismaleimide compound (B1) is preferably 500 or more and 8000 or less, and more preferably 1500 or more and 5000 or less. If the number average molecular weight is less than 500, the heat resistance tends to decrease, and if it exceeds 5000, the moldability tends to decrease, which is not preferable.

（式中、Ｑは炭素数６以上の２価の直鎖状、分枝鎖状又は環状の脂肪族炭化水素基を示し、Ｐは２価の原子又は基であって、Ｏ、ＣＯ、ＣＯＯ、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２、Ｓ、Ｓ_２、ＳＯ及びＳＯ_２から選ばれる２価の原子又は基を少なくとも１つ以上含む基であり、ｍは１〜１０の整数を表す。） Further, as the component (B), the bismaleimide compound (B2) represented by the following general formula (2) is preferably mentioned.

(Wherein, Q is a divalent linear, branched or cyclic aliphatic hydrocarbon group having at least 6 carbon atoms, P is a divalent atom or group, O, CO, _{COO, CH 2, C (CH} 3) 2, C (CF 3) 2, S, is also a divalent atom selected from S 2, SO and SO ₂ is at least one or more group containing group, m Represents an integer of 1-10.)

Here, the group represented by Q preferably has 6 to 44 carbon atoms, the divalent atom represented by P includes O, S and the like, and the divalent group is CO, COO, CH _{2 , C (CH 3) 2,} C (CF 3) 2, S 2, SO, SO 2 , etc., also, these atoms or include organic groups containing at least one or more groups. Examples of the organic group containing an atom or group described above, a structure other than the above hydrocarbon group having 1 to 3 carbon atoms, a benzene ring, cyclopentane ring, can be mentioned those having a urethane bond or the like, as P in that case Examples of groups represented by the following chemical formulas can be given.

Examples of the bismaleimide compound (B2) include BMI-1500 (manufactured by Digigner Moleculars, trade name; molecular weight 1500) and the like.

This component (B) may be used alone or in combination of two or more. The higher the compounding ratio of the component (B), the smaller the water absorption rate, and a sealing resin composition having good reflow resistance can be obtained.

Further, when mixing two or more of the components (B), it is preferable to use the bismaleimide compound (B1) and the bismaleimide compound (B2) in combination. At this time, it is preferable to use the bismaleimide compound (B1) and (B2) in combination at a ratio of (B1) / (B2) of 50/50 to 95/5 on a mass basis. When (B1) is 50 or more in the above ratio, the heat resistance is improved, and when it is 95 or less, the moldability is good, which is preferable. That is, when (B1) / (B2) is in the above range, a sealing resin composition having high heat resistance and good moldability can be obtained.

The compounding ratio (A): (B) of the (A) epoxy resin and (B) bismaleimide resin described above is preferably 95: 5 to 50:50, more preferably 85: 15 to 60:40 in terms of mass ratio. preferable. Within such a range, it is possible to obtain a sealing resin composition having excellent heat resistance, low stress, and good reflow resistance.

In the sealing resin composition of the present invention, the phenol curing agent (C) mainly has an action of enhancing moldability. The phenol curing agent (C) can be used without particular limitation as long as it has two or more phenolic hydroxyl groups in one molecule capable of reacting with the epoxy group of the epoxy resin of the component (A).

Specifically, for example, phenolic compounds having two phenolic hydroxyl groups in one molecule, such as resorcin, catechol, bisphenol A, bisphenol F, substituted or unsubstituted biphenol; phenol, cresol, xylenol, resorcin, catechol. , Phenols such as bisphenol A, bisphenol F, phenylphenol, aminophenol and / or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene, and aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde. A novolak-type phenolic resin obtained by condensing or co-condensing with an acidic catalyst; a phenol aralkyl resin and naphthol synthesized from the above phenols and / or naphthols and dimethoxyparaxylene, bis (methoxymethyl) biphenyl and the like. Aralkyl-type phenolic resins such as aralkyl resin and biphenyl aralkyl resin; modified resins such as paraxylylene-modified phenolic resin, methaxylylene-modified phenolic resin, melamine-modified phenolic resin, and terpene-modified phenolic resin; Dicyclopentadiene-type phenolic resin, dicyclopentadiene-type naphthol resin; polycyclic aromatic ring-modified phenolic resin; biphenyl-type phenolic resin; triphenylmethane-type phenolic resin, etc., which are synthesized by copolymerization from. Further, it may be a phenol resin obtained by copolymerizing two or more of the above phenol resins. As the phenol curing agent (C), one type may be used alone, or two or more types may be used in combination.

As the phenol curing agent (C), an aralkyl type phenol resin is preferable, and a phenol aralkyl resin and a biphenyl aralkyl resin are particularly preferable.

The amount of the (C) phenol curing agent to be blended is usually 1 to 30 parts by mass with respect to 100 parts by mass of the total amount of the (A) epoxy resin and (B) the bismaleimide resin having an aliphatic hydrocarbon group in the main chain. It is preferably 5 to 20 parts by mass. If the blending amount of the phenol curing agent (C) is less than 1 part by mass or exceeds 30 parts by mass, the moldability may be lowered.

In the sealing resin composition of the present invention, the curing accelerator (D) is not particularly limited as long as it is generally used as a curing accelerator for epoxy resins. Specifically, for example, 1,8-diazabicyclo [5.4.0] undecene-7,1,5-diazabicyclo [4.3.0] nonen-5,5,6-dibutylamino-1,8- Cycloamidine compounds such as diazabicyclo [5.4.0] undecene-7; these cycloamidine compounds include maleic anhydride, 1,4-benzoquinone, 2,5-turquinone, 1,4-naphthoquinone, 2,3-dimethyl. Kinone compounds such as benzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, phenyl-1,4-benzoquinone, and compounds having a π bond such as diazophenylmethane and phenol resin. Compounds having intramolecular polarization formed by adding benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol and other tertiary amine compounds and derivatives thereof; 2-methylimidazole, 2-ethyl Imidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl -5-Hydroxymethylimidazole, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- Diamino having an imidazole ring such as (1')] -ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')] -ethyl-s-triazine Imidazole compounds such as −s-triazine compounds and derivatives thereof; organic phosphine compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris (4-methylphenyl) phosphine, diphenylphosphine, phenylphosphine; these organic phosphine compounds Maleic anhydride, 1,4-benzoquinone, 2,5-torquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4 -A phosphorus compound having intramolecular polarization by adding a quinone compound such as benzoquinone or phenyl-1,4-benzoquinone, or a compound having a π bond such as diazophenylmethane or phenol resin; tetraphenylphosphonium tetraphenyl Tetra-substituted phosphonium-tetra-substituted borates such as borate, tetraphenylphosphonium ethyltriphenylborate, tetrabutylphosphonium tetrabutylborate; tetras such as 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmorpholin tetraphenylborate, etc. Examples thereof include phenylborone salts and derivatives thereof. (D) As the curing accelerator, one type may be used alone, or two or more types may be used in combination.

As the (D) curing accelerator, an imidazole-based curing accelerator is preferable, and the above-mentioned imidazole compound is particularly preferable.

The amount of the (D) curing accelerator to be blended is usually 0.2 to 8 with respect to 100 parts by mass of the total amount of the (A) epoxy resin and (B) the bismaleimide resin having an aliphatic hydrocarbon group in the main chain. It is in the range of 0 parts by mass, preferably 1.0 to 5.0 parts by mass. (D) If the blending amount of the curing accelerator is less than 0.2 parts by mass, it is not so effective in improving the curability, and if it exceeds 8.0 parts by mass, the fluidity of the composition is lowered and not yet. Molding defects such as filling may occur.

In the sealing resin composition of the present invention, the inorganic filler (E) is not particularly limited as long as it is generally used for the sealing resin composition. Specifically, molten silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate, potassium titanate, barium titanate, silicon carbide, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, fosterite, steer. Powders such as tight, spinel, mullite, and titania, spherical beads, single crystal fibers, glass fibers, and the like can be used. (E) As the inorganic filler, one type may be used alone, or two or more types may be used in combination.

As the inorganic filler (E), molten silica is preferable from the viewpoint of reducing the coefficient of thermal expansion, and alumina is preferable from the viewpoint of increasing high thermal conductivity. Further, the shape of the inorganic filler is preferably spherical from the viewpoint of improving the fluidity during molding and suppressing the wear of the mold. In particular, considering the balance between cost and performance, it is preferable to use fused silica as the (E) inorganic filler, and it is more preferable to use spherical fused silica.

The blending ratio of the inorganic filler (E) is 70 to 95% by mass, preferably 82 to 91% by mass, based on the total amount of the sealing resin composition. If the blending ratio of the inorganic filler (E) is less than 70% by mass, the coefficient of linear expansion increases and the dimensional accuracy, moisture resistance, mechanical strength, etc. of the molded product decrease. On the other hand, if it exceeds 95% by mass, the melt viscosity increases, the fluidity decreases, and the moldability becomes poor.

The sealing resin composition of the present invention is generally blended with the resin composition for sealing electronic components in addition to the above-mentioned components (A) to (E), which are essential components, as long as the effects of the present invention are not impaired. Other additives may be added as needed. Other additives include flame retardants; coupling agents; mold release agents such as synthetic waxes, natural waxes, higher fatty acids, and metal salts of higher fatty acids; colorants such as carbon black and cobalt blue; silicone oils, silicone rubbers, etc. Modulators; Stabilizers such as hydrotalcites, ion trappers and the like. Each of these additives may be used alone or in combination of two or more.

Specific examples of the flame retardant include a halogen-based flame retardant, an antimony trioxide, an aluminum hydroxide, a magnesium hydroxide, a zinc oxide and other metal elements, a phosphorus-based flame retardant such as a phosphoric acid ester, and the like. ..

Specific examples of the coupling agent include epoxysilane-based, aminosilane-based, ureidosilane-based, vinylsilane-based, alkylsilane-based, organic titanate-based, and aluminum alcoholate-based coupling agents. From the viewpoint of improving curability, aminosilane-based coupling agents are particularly preferable, and in particular, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropyl. Methyldiethoxysilane and 3-phenylaminopropyltrimethoxysilane are preferred.

In the sealing resin composition of the present invention, the blending amount of the above optional components is preferably 0.05 to 3% by mass, preferably 0.1 to 1.5% by mass, based on the total amount of the composition. Is more preferable.

In preparing the sealing resin composition of the present invention, (A) epoxy resin, (B) bismaleimide resin having an aliphatic hydrocarbon group in the main chain, (C) phenol curing agent, and (D) curing acceleration After sufficiently mixing (dry blending) the agent, (E) inorganic filler and various components to be blended as necessary with a mixer or the like, melt-kneading with a kneading device such as a hot roll or kneader, cooling, and then It may be crushed to an appropriate size.

The sealing resin composition of the present invention can be used for coating, insulating, sealing and the like of various electric parts or various electronic parts such as semiconductor elements. Examples of semiconductor elements include transistors, integrated circuits, diodes, thyristors, and the like. As a method for sealing an electronic component such as a semiconductor element with the sealing resin composition of the present invention, a molding method such as a transfer mold, a compression mold, or an injection mold is used. Molding can be performed, for example, at a temperature of 120 to 200 ° C. and a pressure of 2 to 20 MPa. By molding and sealing electronic components such as semiconductor elements under such conditions, it is possible to obtain resin-sealed electronic component devices and semiconductor devices that have excellent reflow resistance and high reliability during high-temperature operation. it can.

Next, the present invention will be described in more detail with reference to Examples. The present invention is not limited to these examples.

(Example 1)
As components (A), 3.0 parts by mass of biphenyl type epoxy resin (trade name: YX-4000H, manufactured by Mitsubishi Chemical Co., Ltd., epoxy equivalent 192, melting point 105 ° C.) and biphenyl aralkyl type epoxy resin (trade name: NC-) 3000, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 276, softening point 57 ° C.) 5.5 parts by mass, solid bismaleimide having an aliphatic hydrocarbon group in the main chain of the above formula (1) as the component (B). Resin (trade name: BMI-5000, manufactured by Digigner Moleculars; number average molecular weight 5000) 2.0 parts by mass, as component (C), biphenyl aralkyl resin (trade name: HE200C-10, Air Water Co., Ltd.) ), Hydropoxy equivalent 205, softening point 70 ° C.) 1.0 part by mass, as component (D), 2,4-diamino-6- [2'-methylimidazolyl (1')]-ethyl-s-triazine ( Product name: 2MZA, manufactured by Shikoku Kagyo Co., Ltd., 0.3 parts by mass, (E) Spherical molten silica as an inorganic filler (trade name: FB-105, manufactured by Electrochemical Industry Co., Ltd., average particle size 11 μm) 87.0 parts by mass, 0.4 parts by mass of 3-phenylaminopropyltrimethoxysilane (trade name: Z-6883, manufactured by Toray Doukoning Co., Ltd.) as a silane coupling agent, carnauba wax as a release agent (Product name: Carnauba wax No. 1, manufactured by Toyo Adre Co., Ltd.) 0.2 parts by mass, as a stabilizer, synthetic hydrotalcite (trade name: DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) 0.3 mass As a part and a colorant, 0.3 parts by mass of carbon black (trade name: MA-100, manufactured by Mitsubishi Chemical Co., Ltd.) is mixed at room temperature using a mixer, and then 70 ° C to 110 ° C using a thermal roll. Was heated and kneaded, cooled and then pulverized to obtain a sealing resin composition.

(Example 2)
As the component (C), instead of the biphenyl aralkyl resin (HE200C-10), a phenol aralkyl resin (trade name: HE100C-10, manufactured by Air Water Co., Ltd., hydroxyl group equivalent 168, softening point 68 ° C.) 1.0 mass A resin composition for sealing was obtained in the same manner as in Example 1 except that the portion was used.

(Example 3)
As component (D), 2-phenyl-4-methyl-5-hydroxymethyl instead of 2,4-diamino-6- [2'-methylimidazole (1')]-ethyl-s-triazine (2MZA) A sealing resin composition was obtained in the same manner as in Example 1 except that 0.3 parts by mass of imidazole (trade name: 2P4MHZ, manufactured by Shikoku Chemicals Corporation) was used.

(Example 4)
The amount of the biphenyl type epoxy resin (YX-4000H) as the component (A) was 1.0 part by mass, and the amount of the biphenylimide resin as the component (B) was 4.0 parts by mass. Similarly, a sealing resin composition was obtained.

(Comparative Example 1)
The amount of the component (A) biphenyl type epoxy resin (YX-4000H) is 1.5 parts by mass, the amount of the biphenyl aralkyl type epoxy resin (NC-3000) is 3.0 parts by mass, and the amount of the component (B) screw. A sealing resin composition was obtained in the same manner as in Example 1 except that the amount of the maleimide resin blended was 6.0 parts by mass.

(Comparative Example 2)
The amount of the biphenyl type epoxy resin (YX-4000H) of the component (A) is 4.0 parts by mass, and the amount of the biphenyl aralkyl type epoxy resin (NC-3000) is mixed without blending the component (B) bismaleimide resin. A resin composition for encapsulating electronic parts was obtained in the same manner as in Example 1 except that the amount was 6.5 parts by mass.

Various characteristics of the sealing resin compositions obtained in each of the above Examples and Comparative Examples were evaluated by the methods shown below. The results are shown in Table 1 together with the composition.

[Evaluation methods]
(1) Glass transition temperature (Tg)
The sealing resin composition is transfer-molded under the conditions of a mold temperature of 180 ° C., a molding pressure of 8.0 MPa, and a molding time of 2 minutes to prepare a molded product having a length of 15 mm, a width of 4 mm, and a thickness of 3 mm. After curing at 175 ° C. for 8 hours, a test piece was obtained. The obtained test piece was analyzed by thermomechanical analyzer (trade name: TMA / SS150, manufactured by Shimadzu Corporation) at a heating rate of 5 ° C./min by compression measurement in air, and then thermomechanical analysis was performed. An analytical (TMA) curve was obtained. The temperature at the intersection of the tangents of 60 ° C. and 240 ° C. of the obtained TMA curve was read, and this temperature was taken as the glass transition temperature (unit: ° C.).

(2) Elastic modulus during heat The sealing resin composition was transfer-molded under the conditions of a mold temperature of 180 ° C., a molding pressure of 8.0 MPa, and a molding time of 2 minutes to obtain a length of 45 mm, a width of 4 mm, and a thickness of 3 mm. A molded product was prepared, and further cured at 175 ° C. for 8 hours to obtain a test piece. The obtained test piece was analyzed in air at a heating rate of 5 ° C./min and a frequency of 10 Hz using a dynamic viscoelasticity test device (trade name: DMA Q800, manufactured by TA Instruments). The elastic modulus at 260 ° C. was determined. This value was taken as the thermal elastic modulus (unit: GPa).

(3) Pressure Cooker (PC) Water Absorption Rate The sealing resin composition is transfer-molded under the conditions of a mold temperature of 180 ° C., a molding pressure of 8.0 MPa, and a molding time of 2 minutes to form a circle having a diameter of 50 mm and a thickness of 3 mm. A plate-shaped molded product was prepared, and further cured at 175 ° C. for 8 hours to obtain a test piece. The mass of the obtained test piece before the PC test (before the moisture absorption treatment) and the mass after the PC test (after the moisture absorption treatment) were measured, and the PC water absorption rate (unit:%) of the test piece was calculated by the following formula. The PC test was carried out under the conditions of temperature: 127 ° C., pressure: 2 atm (about 0.2 MPa), and relative humidity: 100% RH for 24 hours.

PC water absorption rate = {(mass after moisture absorption treatment-mass before moisture absorption treatment) / mass before moisture absorption treatment} x 100 (%)

(4) Moldability IC package VQFP80 (package size: 14 mm × 14 mm × 1.4 mm, copper (Cu) frame, with silver (Ag) ring plating) is molded at a mold temperature of 180 ° C. with a sealing resin composition. Transfer molding was performed under the conditions of a molding pressure of 12.0 MPa and a molding time of 2 minutes. While visually observing the appearance of the obtained 3 shots (6 frames) of the molded product, voids are generated inside and outside by the ultrasonic flaw detector (manufactured by Hitachi Construction Machinery Finetech Co., Ltd., trade name: FS300II). I observed the situation. In addition, the presence or absence of Kal runner breakage was investigated. These were judged according to the following criteria.

<Abnormal appearance / void occurrence>
◯: Abnormal appearance and no voids △: Voids with a diameter of 0.5 mm or less are generated ×: Voids with a diameter of more than 0.5 mm are generated

<Break of Cal Runner>
○: Yes ×: No

(5) Reflow resistance To 32 molded products of the package (VQFP80) produced in (4) above, after curing at 175 ° C. for 8 hours, then 30 ° C., relative humidity 60% RH, 192 hours. Moisture absorption treatment was performed. After that, it is heated in an infrared reflow furnace at 260 ° C., and after cooling, the presence or absence of peeling at the interface between the cured resin product and the frame and the interface between the cured resin product and the semiconductor chip is examined by the above ultrasonic flaw detector, and peeling is performed. Was counted.

(6) Temperature cycle test An 8 mm square evaluation chip (TEG chip) is mounted on a frame for QFP208 (package size: 28 mm x 28 mm x 2.7 mm, copper (Cu) frame, silver (Ag) spot plating). Then, a Cu wire coated with palladium (Pd) having a diameter of 25 μm was bonded. Next, the test semiconductor device is subjected to transfer molding using the sealing resin composition under the conditions of a mold temperature of 180 ° C., a molding pressure of 12.0 MPa, and a molding time of 2 minutes, and further performing post-curing at 175 ° C. for 8 hours. Made. The obtained test semiconductor device was tested for 1000 cycles in a temperature range of −65 to 150 ° C., and the number of OPEN defects (defects due to disconnection of wiring) was examined (total number of samples = 16).

From Table 1, it can be seen that the sealing resin compositions of Examples 1 to 4 have excellent moldability, high Tg, low thermal elastic modulus, and low hygroscopicity. In addition, the sealing resin compositions of Examples 1 to 4 have excellent reflow resistance and good temperature cycle test results, and it can be seen that a highly reliable semiconductor device can be obtained by using this. On the other hand, in the comparative example, the property evaluation results of any of the moldability, Tg, elastic modulus, hygroscopicity, reflow resistance and temperature cycle test are poor, and a highly reliable semiconductor device cannot be obtained. I understand.

Claims (4)

(A) epoxy resin, (B) bismaleimide resin having an aliphatic hydrocarbon group in the main chain, containing at least one represented by the following general formulas (1) and (2), (C) phenol curing agent, A resin composition containing (D) a curing accelerator and (E) an inorganic filler.
The compounding ratio (A): (B) of the (A) epoxy resin and the (B) bismaleimide resin is 95: 5 to 50:50 in terms of mass ratio, and the content of the (E) inorganic filler is Is a sealing resin composition, which is 70 to 95% by mass of the whole composition.

(In the formula, n represents an integer of 1 to 10.)

(In the formula, Q represents a divalent linear, branched or cyclic aliphatic hydrocarbon group having 6 or more carbon atoms, and P is O, CO, COO, CH ₂ , C (CH ₃ ) _{2 , C (CF 3) 2,} S, S 2, 2 -valent atom or group selected from SO, and SO _2, or, or these atoms is an organic group containing at least one group, m is 1 Represents an integer of 10.) 1 to 30 parts by mass of (C) phenol curing agent and 0.2 to 8.0 parts by mass of (D) curing accelerator with respect to 100 parts by mass of the total amount of (A) epoxy resin and (B) bismaleimide resin. The sealing resin composition according to claim 1, wherein the resin composition contains a portion. (D) The sealing resin composition according to claim 1 or 2, wherein the curing accelerator contains an imidazole-based curing accelerator. A semiconductor device, wherein the semiconductor element is sealed by a cured product of the sealing resin composition according to any one of claims 1 to 3.