JP2013001861A - Resin composition for semiconductor sealing, production method thereof, and semiconductor apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for semiconductor sealing, excellent in thermal conductivity, moldability, humidity-tolerant reliability and reflow resistance, and to provide a production method thereof and a semiconductor apparatus.SOLUTION: The resin composition for semiconductor sealing contains a cresol novolak type epoxy resin, phenol novolak resin, curing accelerator, silica containing at least crystalline silica of an average particle diameter of 10-60 μm, and SiC of an average particle diameter of 10-80 μm, obtained by heat treatment at ≥800°C, wherein a total content of silica and SiC is 75-90 mass%, a volume filling factor of the crystalline silica is ≥25 vol.% and ≤50 vol.%, and a volume filling factor of SiC is ≥20 vol.% and ≤37 vol.%. The production method of the resin composition and the semiconductor apparatus are provided.

Description

  The present invention relates to a resin composition for encapsulating a semiconductor suitable for power device applications, a method for producing the same, and a semiconductor device using the same.

  Epoxy resin compositions used for resin sealing of semiconductor devices such as power devices are required to have high thermal conductivity in order to cope with a large amount of heat released from semiconductor elements. Therefore, in order to obtain a good thermal conductivity, for example, an epoxy resin composition in which crystalline silica and fused spherical silica having a small particle diameter are used in combination and an inorganic filler is filled at a high density has been proposed ( For example, see Patent Documents 1 and 2).

  Crystalline silica has a higher thermal conductivity than fused silica, etc., so when it is used as a filler, high thermal conductivity can be expected. However, it has a drawback that good fluidity cannot be obtained. In order to solve this problem, a semiconductor sealing resin composition containing obtuse crystalline silica powder has been proposed (see, for example, Patent Document 3). However, it cannot be said that the fluidity is sufficiently improved.

Further, the surface includes a silicon carbide powder whose surface is oxidized at a temperature of 800 ° C. or higher, an insulating powder, and a resin, and the volume filling rate of the insulating powder is ½ or less of the volume filling rate of the silicon carbide powder. A certain resin composition has been proposed (see, for example, Patent Document 4). This is because although silicon carbide has high thermal conductivity, it has many impurities and is electrically a semiconductor, so it cannot be used for applications that require insulation as it is. It can be used as an inorganic filler by forming a layer.
However, when such silicon carbide powder is used as a sealing resin for a semiconductor device, the fluidity is poor and the filling property in the mold is inferior, so that the reflow resistance at the time of moisture absorption may be inferior.

Japanese Patent No. 2811933 JP 2001-44337 A JP-A-8-81540 JP 2007-84705 A

  The present invention was made to solve the above-described problems of the prior art, has a good thermal conductivity, and has a moldability, reflow resistance, and moisture resistance reliability, and a semiconductor sealing resin composition, and It aims at providing the manufacturing method.

  As a result of intensive studies to achieve the above object, the present inventors have found that in a resin composition for semiconductor encapsulation containing cresol novolac type epoxy resin, phenol novolac resin, curing accelerator, silica, and silicon carbide as essential components. By adjusting specific silica and silicon carbide to a specific blending ratio, a resin composition for semiconductor encapsulation having good thermal conductivity and excellent moldability, moisture resistance reliability, and reflow resistance can be obtained. As a result, the present invention has been completed.

  That is, this invention provides the following resin compositions for semiconductor sealing, its manufacturing method, and a semiconductor device.

1. (A) Cresol novolac type epoxy resin, (B) phenol novolac resin, (C) curing accelerator, (D) silica, and (E) silicon carbide, (D) total content of silica and (E) silicon carbide It is a resin composition for semiconductor encapsulation whose amount is 75 to 90% by mass of the total resin composition,
(D) The silica contains at least crystalline silica (d1) having an average particle size of 10 to 60 μm, and the volume filling rate of (d1) crystalline silica in the resin composition is 25% by volume or more and 50% by volume or less. ,
(E) Silicon carbide is silicon carbide having an average particle diameter of 10 to 80 μm that is heat-treated at 800 ° C. or higher, and the volume filling rate of (E) silicon carbide in the resin composition is 20% by volume or more and 37% by volume. The resin composition for semiconductor sealing which is the following.
2. The (D) silica further includes crystalline silica (d2) having an average particle diameter of less than 10 μm, which is pulverized by a jet mill method, and the volume filling rate of (d2) crystalline silica in the resin composition is 1 volume. The resin composition for semiconductor encapsulation according to 1 above, wherein the content is 1% or more and 10% by volume or less.
3. The resin composition for semiconductor encapsulation according to 1 or 2, wherein a volume filling rate of the (E) silicon carbide is smaller than a volume filling rate of the (D) silica.
4). A method for producing a resin composition for encapsulating a semiconductor according to any one of 1 to 3, which comprises a step of pre-kneading (B) a phenol novolac resin and (E) silicon carbide in advance. Manufacturing method.
5. The semiconductor device which comprises the semiconductor element sealed with the hardened | cured material of the resin composition for semiconductor sealing in any one of said 1-3, or the hardened | cured material of the resin composition for semiconductor sealing obtained by the said 4 method. .

  INDUSTRIAL APPLICABILITY The present invention can provide a semiconductor sealing resin composition excellent in thermal conductivity, moldability, reflow resistance, and moisture resistance reliability, a manufacturing method thereof, and a semiconductor sealing device.

First, each component used for the resin composition for semiconductor encapsulation of this invention is demonstrated.
The (A) component cresol novolac type epoxy resin used in the present invention is characterized by excellent moldability and solder heat resistance. The cresol novolac type epoxy resin is represented by the following general formula (1), and among them, an o-cresol novolac type epoxy resin is preferable.

(In the formula, n is an integer of 0 or more.)
The epoxy equivalent of the cresol novolak type epoxy resin is preferably in the range of 150 to 300, more preferably in the range of 180 to 250, from the viewpoint of curability.
As the component (A), specifically, ESCN-190 (manufactured by Sumitomo Chemical Co., Ltd., trade name of o-cresol novolac type epoxy resin; epoxy equivalent 195, softening point 65 ° C.) and the like are preferably used. A cresol novolac type epoxy resin may be used individually by 1 type, and 2 or more types may be mixed and used for it.

  In the present invention, if necessary, an epoxy resin other than the cresol novolac type epoxy resin of component (A) can be used in combination. The epoxy resin other than the component (A) is not particularly limited as long as it is a compound having two or more epoxy groups in one molecule. For example, a phenol novolac type epoxy resin or bisphenol is used for the purpose of adjusting curability or the like. A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, naphthalene type epoxy resin, triphenolmethane type epoxy resin, triazine nucleus-containing epoxy resin, biphenyl type or stilbene type bifunctional epoxy compound may be used. it can. These epoxy resins may be used individually by 1 type, and 2 or more types may be mixed and used for them. (A) When using together epoxy resin other than a component, it is preferable to mix | blend in the range of 50 mass% or less of epoxy resin total mass. A more preferable range is 30% by mass or less of the total mass of the epoxy resin.

As the phenol novolak resin of component (B) used in the present invention, if it has two or more phenolic hydroxyl groups in the molecule that can react with the epoxy group of the cresol novolak type epoxy resin of component (A), It is used without particular limitation. For the purpose of the present invention, the phenolic hydroxyl group equivalent of the component (B) is preferably in the range of 100 to 200, and particularly preferably in the range of 100 to 150 from the viewpoint of curability. The softening point of the component (B) is preferably in the range of 50 to 130 ° C, more preferably in the range of 70 to 110 ° C.
Specifically, as the component (B), TEH-1085 (trade name, manufactured by Meiwa Kasei Co., Ltd .; hydroxyl equivalent 104, softening point 102 ° C.) and the like are preferably used. As the component (B), the phenol novolac resin may be used alone or in combination of two or more.

  The amount of this phenol novolak resin is the same as that in the phenol novolac resin per equivalent of epoxy group in the cresol novolak type epoxy resin of the component (A) and the epoxy resin other than the component (A) blended as necessary. The range in which the phenolic hydroxyl group equivalent is 0.5 to 2.0 equivalents is preferable, and the range in which 0.8 to 1.2 equivalents is more preferable. Flame retardance etc. improve that it is the range of 0.5 equivalent or more. Moreover, a water absorption falls that it is the range of 2.0 equivalent or less, and moisture-proof reliability improves.

In this invention, the phenol resin which acts as a hardening | curing agent of the said epoxy resin other than (B) phenol novolak resin can be used together as needed. Specifically, the phenol resin other than the component (B) includes a cresol novolak resin, a phenol aralkyl resin, a naphthol aralkyl resin, a modified resin of a novolak type phenol resin (for example, a phenol novolak resin, a cresol novolak resin, etc.) Alternatively, butylated novolac-type phenol resin, dicyclopentadiene-modified phenol resin, para-xylene-modified phenol resin, triphenolalkane-type phenol resin, polyfunctional phenol resin, and the like can be used.
These may be used individually by 1 type, and may mix and use 2 or more types. (B) When using together phenol resin other than a component, it is preferable to mix | blend in the range of 50 mass% or less of phenol resin total mass, and it is more preferable to mix | blend in 30 mass% or less of phenol resin total mass. When a phenol resin other than the phenol novolak resin of component (B) is used in combination, the phenolic hydroxyl group equivalent in the resin is a clarine novolak type epoxy resin of component (A), and other blended as necessary. The above-described range, that is, a range of 0.5 to 2.0 equivalents, and a range of 0.8 to 1.2 equivalents are more preferable per equivalent of epoxy group in the epoxy resin.

There is no restriction | limiting in particular as (C) hardening accelerator used for this invention, A well-known thing can be used widely. (C) Examples of the curing accelerator include trimethylphosphine, triethylphosphine, tributylphosphine, triphenylphosphine, tri (p-methylphenyl) phosphine, tri (nonylphenylphosphine), methyldiphenylphosphine, dibutylphenylphosphine, tricyclohexyl. Phosphorous curing accelerators such as phosphine, 1,2-bis (diphenylphosphino) ethane, bis (diphenylphosphino) methane, 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, Imidazole curing accelerators such as 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, and DBU systems such as 1,8-diazabicyclo [5,4,0] undecene-7 (DBU) Accelerator, and the like. These may be used alone or in combination of two or more.
(C) It is preferable to mix | blend the mixture ratio of a hardening accelerator so that it may contain 0.01-5 mass% with respect to all the resin compositions. When the proportion is 0.01% by mass or more, the gel time of the resin composition is shortened and the curing characteristics are improved. On the other hand, if it is 5% by mass or less, the fluidity is good, the moldability is improved, and the electrical properties are also good, so that moisture resistance reliability is obtained.

  As (D) silica used in the present invention, at least crystalline silica (d1) having an average particle diameter of 10 to 60 μm is used. (D1) By using crystalline silica, high thermal conductivity can be imparted to the obtained sealing resin, which is suitable for a sealing resin that requires high thermal conductivity such as a power device. Compared with amorphous silica and the like, excellent properties can be imparted. From the above viewpoint, the average particle diameter of (d1) crystalline silica is preferably in the range of 30 to 60 μm, and more preferably in the range of 40 to 60 μm.

Furthermore, it is preferable to use crystalline silica (d2) having an average particle diameter of less than 10 μm, which is pulverized by a jet mill method as (D) silica. (D2) By blending crystalline silica pulverized by jet mill, a semiconductor sealing resin composition having high thermal conductivity, good moldability and filling properties, and excellent reflow resistance can be obtained. .
(D2) The average particle diameter of the crystalline silica is more preferably in the range of 1 μm or more and less than 10 μm. Furthermore, (d2) crystalline silica preferably has an average ratio of the major axis to the minor axis in the range of 1 to 1.5. Here, crystalline silica has a higher thermal conductivity than fused silica, but its shape is indeterminate and may have poor filling properties. Therefore, by using crystalline silica pulverized by such a jet mill method, a rounded shape is obtained with a rounded corner, and high-density filling is possible without using fused spherical silica.
In the present invention, the average particle diameter of (d2) crystalline silica was determined as follows. That is, using a photograph of sampled jet mill pulverized silica photographed with an electron microscope at a magnification of 500 times, the diameter of a circle equal to the photographing area is obtained for 100 arbitrarily selected particles, and the arithmetic average value is used as the average particle diameter. did. In addition, the major axis and the minor axis were obtained by using the above-mentioned photograph, and the diameter of the circumscribed circle of the particle was selected as the major axis for 100 arbitrarily selected particles, and the shortest distance between the parallel lines in contact with the particle contour was defined as the minor axis.

The jet mill pulverization method is a pulverization method that uses fluid energy generated by the air flow inside the mill equipment and makes particles collide with each other and physically pulverizes by collision with the vessel wall. Fine pulverization is possible. It is. By performing jet mill grinding, fine powder having a relatively uniform particle diameter can be obtained.
In the present invention, the silica particles pulverized by the jet mill method are prepared by introducing crystalline silica particles at a jet airflow pressure of ² to 10 kg / cm ² using, for example, an apparatus PJM-200SP manufactured by Nippon Pneumatic Industry Co., Ltd. Obtainable. Moreover, you may use what is marketed suitably.
Moreover, in this invention, fused silica can also be mix | blended as needed in the range which does not inhibit the effect of this invention as (D) silica other than (d1) and (d2) component.

The silicon carbide (E) used in the present invention is characterized by being heat-treated at 800 ° C. or higher. By performing the heat treatment at 800 ° C. or higher, particularly ionic impurities contained in silicon carbide are reduced. Specifically, by heat-treating silicon carbide at 1100 ° C. for 2 hours in an oxygen atmosphere, sodium ions contained in silicon carbide are reduced to 1/5 or less and chlorine ions are reduced to 1/10 or less. The electrical conductivity of the extracted water after being immersed in pure water at 180 ° C. for 2 hours is reduced to 1/3 or less. Thereby, the moisture resistance reliability of the resin composition for semiconductor encapsulation is improved, and a highly reliable resin-encapsulated semiconductor device can be obtained with a high yield.
The heat treatment method of the silicon carbide is not particularly limited, and examples thereof include a thermal oxidation method in an air or oxygen atmosphere.
(E) As heat processing temperature of silicon carbide, 800-1200 degreeC is preferable and 900-1100 degreeC is more preferable.

The average particle diameter of (E) silicon carbide used in the present invention is 10 to 80 μm, and preferably 30 to 60 μm.
(E) When the average particle diameter of silicon carbide is in the range of 10 μm or more, good thermal conductivity is obtained, and in the range of 80 μm or less, proper fluidity is obtained.

  By combining (d1) crystalline silica having an average particle diameter of 10 to 60 μm and (E) silicon carbide having an average particle diameter of 10 to 80 μm that has been heat-treated at 800 ° C. or higher, preferably (d2) By combining crystalline silica having an average particle diameter of less than 10 μm that has been pulverized by jet mill, the balance between thermal conductivity and fluidity is improved.

In the present invention, the total content of the (D) silica and the (E) silicon carbide is 75 to 90% by mass, preferably 80 to 90% by mass, based on the entire composition. When the total content of the components (D) and (E) is within this range, the fluidity is excellent and good thermal conductivity is obtained.
Moreover, in the resin composition for semiconductor encapsulation of the present invention, the volume filling rate of the (d1) silica in the composition is 25% by volume or more and 50% by volume or less, and the (E) silicon carbide in the composition The volume filling factor is 20 volume% or more and 37 volume% or less. Furthermore, it is preferable that the volume filling rate of the (d2) silica in the composition is 1% by volume or more and 10% by volume or less.
When the volume filling rate of the (E) silicon carbide is less than 20% by volume, the desired thermal conductivity cannot be obtained, which is not preferable. Moreover, when the volume filling rate of the said (d1), (E), and (d2) component exists in this range, while being excellent in fluidity | liquidity, favorable heat conductivity is obtained.

  Furthermore, it is preferable that the volume filling rate of the (E) silicon carbide is smaller than the volume filling rate of the (D) silica. When the volume filling rate of silicon carbide increases with respect to the volume filling rate of silica, which is an insulating powder, the moldability is lowered and the reflow resistance and moisture resistance reliability may be lowered. Therefore, the resin composition for semiconductor encapsulation excellent in fluidity, moldability, reflow resistance, and moisture resistance reliability by making the volume filling rate of (E) silicon carbide smaller than the volume filling rate of (D) silica. You can get things.

  In the resin composition for encapsulating a semiconductor of the present invention, a coupling agent can be further blended for the purpose of improving the filling property, the adhesion between the inorganic filler and the resin, and the like. Examples of the coupling agent include silane coupling agents, titanium coupling agents, aluminum chelates, aluminum / zirconium-based compounds, and the like, and silane coupling agents are particularly preferable from the viewpoint of the effect of addition.

  Examples of preferred silane coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β-aminoethyl. -Γ-aminopropyltrimethoxysilane and the like. For example, γ-glycidoxypropyltrimethoxysilane is NUC A-187, γ-mercaptopropyltrimethoxysilane is NUC A-189, γ-aminopropyltriethoxysilane is NUC A-1100, γ-ureidopropyltriethoxysilane. NUC A-1160 and N-β-aminoethyl-γ-aminopropyltrimethoxysilane are trade names NUC A-1120, both of which are commercially available from Nihon Unicar Corporation.

  The blending amount of the coupling agent is preferably in the range of 0.03 to 5.0% by mass with respect to the total amount of the composition, from the viewpoint of the effect by addition, heat resistance, cost, etc. % Range is more preferred.

  In the resin composition for semiconductor encapsulation of the present invention, synthetic wax, natural wax, esters, metal salt of linear fatty acid, acid amide, etc., which are generally blended in this kind of composition in addition to the above components A release agent, a colorant such as carbon black, a low-stress imparting agent such as silicone oil and silicone rubber, and the like can be blended as necessary within a range that does not impair the effects of the present invention.

  In a general method for producing a semiconductor sealing resin composition of the present invention, (D) component silica and (E) component silicon carbide are first added to a dry mixing apparatus and mixed. In addition, (d1) component contained in (D) component and (d2) component used as needed may be added as a powder mixture, or may be individually added to a dry-type mixing apparatus, without mixing beforehand. Next, (A) a cresol novolac type epoxy resin, (B) a phenol novolac resin, (C) a curing accelerator, and various components blended as required are added in a powder state and mixed uniformly. Then, after melt-kneading this mixture with a two roll, a continuous kneader, etc. and making it into a sheet | seat, the resin composition for semiconductor sealing can be obtained by grind | pulverizing to a suitable magnitude | size.

In particular, in the method for producing a semiconductor sealing resin composition of the present invention, it is preferable that the (B) phenol novolac resin and the (E) silicon carbide are previously kneaded to prepare a preliminary kneaded composition. (B) A resin composition for encapsulating a semiconductor excellent in moldability, reflow resistance and moisture resistance reliability by pre-kneading a phenol novolac resin and (E) silicon carbide to uniformly disperse silicon carbide. Can be obtained.
To prepare the pre-kneading composition, the (B) phenol novolac resin and the (E) silicon carbide powder are mixed, and then the resin components can be heated and melt-kneaded such as a kneader, a hot roll, or an extrusion kneader. A method of melting and kneading with a simple apparatus, cooling and solidifying, and then pulverizing to a particle size suitable for preparation of a resin material for semiconductor encapsulation is employed.
The prepared pre-kneading composition is uniformly mixed with (A) component, (C) component, (D) component and various components blended as necessary, and then melt-kneaded in the same manner as above to form a sheet. Then, the resin composition for semiconductor encapsulation can be produced by pulverization.
In addition to pre-kneading by such a method, as described above, by setting the volume filling rate of (E) silicon carbide to be lower than the volume filling rate of (D) silica, (E) dispersibility of silicon carbide is achieved. It is possible to obtain a resin composition for encapsulating a semiconductor which exhibits excellent and good thermal conductivity and is excellent in moldability, reflow resistance and moisture resistance reliability.

  The semiconductor device of this invention can be manufactured by sealing various semiconductor elements using the said resin composition for semiconductor sealing. Examples of the semiconductor Taiko that performs sealing include an IC, a diode, a thyristor, and a transistor. As a sealing method, a low-pressure transfer method is generally used, but sealing by injection molding, compression molding, casting, or the like is also possible. After sealing with the semiconductor sealing resin composition, the semiconductor device is finally heated and cured, and finally sealed with the cured product. The cured product preferably has a thermal conductivity of 2.5 W / m · K or more, more preferably 3.0 W / m · K or more, as measured by a hot wire method.

  The resin composition for encapsulating a semiconductor of the present invention has high thermal conductivity, good fluidity, excellent moldability, and excellent reflow resistance and moisture resistance reliability. Therefore, it is very useful as a sealing material for various semiconductor devices, especially as a sealing material for semiconductor devices such as transistors, diodes, and thyristors called power devices.

  Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not restrict | limited by these Examples.

Example 1
100 parts by mass of (E) silicon carbide (average particle size 35 μm) obtained by heating silicon carbide (manufactured by Fukushima Ceramics Co., Ltd.) at 1100 ° C. for 2 hours in an oxygen atmosphere, and (B) a phenol novolac resin ( Product name: TEH-1085 (manufactured by Meiwa Kasei Co., Ltd.) and 5 parts by mass are mixed at room temperature using a mixer, heated and kneaded at a temperature of 70 to 100 ° C. with a pressure kneader, and cooled and solidified. And pulverized to obtain a pre-kneaded composition.
Next, in addition to the pre-kneaded composition, (A) cresol novolac type epoxy resin (trade name: CNE-200ELB-65, manufactured by Changchun Artificial Resin Co., Ltd.) 15 parts by mass, brominated epoxy resin (trade name: EPICLON153, DIC Corporation) 5 parts by mass, curing accelerator (2-phenyl-4-methylimidazole, trade name: 2P4MZ, Shikoku Kasei Kogyo Co., Ltd.) 1 part by mass, (d1) crystalline silica (average particle size 40- 50 μm, trade name silica powder T, manufactured by Fukushima Ceramics Co., Ltd.) 110 parts by mass, and crystalline silica powder having an average particle size of 28 μm was jetted using a jet mill (PJM-200EP, Nippon Pneumatic Industrial Co., Ltd.). It was charged with to 10 kg / cm ^2, obtained by pulverizing and sieving (d2) jet milling the silica powder (average particle size 5.0 .mu.m) 10 weight , Release agent (trade name: Licowax-E, manufactured by Clariant) 4 parts by mass, colorant (carbon black, product name: CB # 30, manufactured by Mitsubishi Chemical Corporation), 0.6 parts by mass, coupling agent (3 -Glycidoxypropyltrimethoxysilane, trade name: S-510, manufactured by Chisso Corporation) 0.1 parts by mass was mixed at room temperature, then melt-kneaded at 90-110 ° C, cooled and pulverized to seal the semiconductor A resin composition was produced.

(Example 2)
(D2) Example 1 except that 10 parts by mass of fused spherical silica (trade name SO-32R, manufactured by Tatsumori Co., Ltd., average particle size 1.6 to 2.0 μm) was used instead of jet mill pulverized silica powder. In the same manner as above, a resin composition for semiconductor encapsulation was produced.

(Example 3)
In the resin composition of Example 1, silicon carbide and phenol novolac resin were not pre-kneaded, but all materials were mixed together at room temperature, then melt-kneaded at 90 to 110 ° C., cooled and pulverized, for semiconductor encapsulation A resin composition was produced.

Example 4
In the resin composition of Example 2, the silicon carbide and the phenol novolac resin were not pre-kneaded, but all the materials were mixed together at room temperature, then melt-kneaded at 90 to 110 ° C., cooled and pulverized, for semiconductor encapsulation A resin composition was produced.

(Comparative Example 1)
A resin composition for encapsulating a semiconductor was produced in the same manner as in Example 4 except that silicon carbide (not manufactured by Fukushima Ceramics Co., Ltd.) that was not subjected to heat oxidation treatment was used instead of the component (E) used in Example 4. did.

(Comparative Example 2)
150 parts by mass of (E) heat-oxidized silicon carbide used in Example 3, and (d1) 50 parts by mass of crystalline silica (trade name: Silica Powder T, manufactured by Fukushima Ceramics Co., Ltd., average particle size: 40-50 μm) Part (d2) A resin composition for semiconductor encapsulation was produced in the same manner as in Example 3 except that the jet mill pulverized silica powder was changed to 0 part by mass.

(Comparative Example 3)
60 parts by mass of (E) heat-oxidized silicon carbide used in Example 4 and (d1) 140 parts by mass of crystalline silica (trade name: Silica Powder T, manufactured by Fukushima Ceramics Co., Ltd., average particle size: 40-50 μm) A resin composition for encapsulating a semiconductor was produced in the same manner as in Example 4 except that the part was used.

The resin compositions for semiconductor encapsulation obtained in Examples and Comparative Examples were evaluated by the following methods, and the results are shown in Table 1.
(Spiral flow)
A spiral flow mold according to EMMI-1-66 was used to measure the spiral flow length when the semiconductor sealing resin composition was transfer molded at 175 ° C. and a molding pressure of 9.8 MPa.

(Formability evaluation)
20 molds of resin composition for semiconductor encapsulation (using a 3-pin small semiconductor device (size: about 5 mm long × 1.5 mm wide × 0.5 mm height), mold temperature 175 ° C., Molding was performed at an injection pressure of 7.0 MPa and a curing time of 120 seconds, and post-curing was performed for 5 hours at 175 ° C. Thereafter, the number of occurrences of cracks or chips was visually evaluated. The number of generated packages was visually evaluated according to the following criteria.
(Evaluation criteria)
○: No abnormality is observed Δ: Appearance defects such as nest formation are observed ×: Unfilled, cracked or chipped are recognized

(Hygroscopic reflow test)
Using a semiconductor sealing resin composition, a silicon chip having two or more aluminum wirings is bonded to a normal 42 alloy frame, transfer molded at 170 ° C. for 2 minutes, and then post-cured at 170 ° C. for 4 hours. Went. The molded product thus obtained was left to stand for 72 hours in an environment of 85 ° C. and 85% RH, and then subjected to infrared (IR) reflow treatment (240 ° C., 10 seconds).
Twenty molded products were observed with an ultrasonic flaw detector, and the number of defects such as peeling and cracking inside the package was confirmed.

(Extracted water conductivity)
The resin composition for semiconductor encapsulation is pulverized, 5 g is weighed and placed in an extraction container, extracted in 50 ml of pure water at 180 ° C. for 2 hours, and then a conductivity meter (CM-40S, Toa DKK Corporation). The electrical conductivity was measured. When the electrical conductivity of the extracted water is 40 μS / cm or less, it is useful as a highly reliable semiconductor sealing material.

(Moisture resistance reliability test)
Using a semiconductor sealing resin composition, a silicon chip having two or more aluminum wirings is bonded to a normal 42 alloy frame, transfer molded at 170 ° C. for 2 minutes, and then post-cured at 170 ° C. for 4 hours. Went.
Using 20 molded articles thus obtained, a pressure cooker test (PCT) was performed in saturated steam at 127 ° C. and 2.5 atm to confirm the number of occurrences of open / short of the aluminum wiring.

(Thermal conductivity)
A molded product (φ100 mm, 25 mm thickness) obtained by transfer molding of the semiconductor sealing resin composition at 175 ° C. was prepared, and the thermal conductivity (unit: W / m · K) was measured using a rapid thermal conductivity measuring device. . Thermal conductivity was determined according to the following criteria.
(Criteria)
○: Thermal conductivity 3 or more △: Thermal conductivity 2.5 or more and less than 3 ×: Thermal conductivity 2.5 or less

  As shown in the evaluation results of Table 1, the resin compositions for semiconductor encapsulation of Examples 1 to 4 are excellent in fluidity and moldability as compared with the resin compositions for semiconductor encapsulation of Comparative Examples 1 to 3. The cured product was also found to have good results of moisture absorption reflow and a test moisture resistance reliability test. Moreover, it was recognized that it is excellent in thermal conductivity.

The resin composition for encapsulating a semiconductor of the present invention exhibits good thermal conductivity, is excellent in reflow resistance and moisture resistance reliability, and is excellent in moldability because of no unfilling and excellent reliability. A semiconductor device can be obtained.
Furthermore, according to the method for producing a resin composition for encapsulating a semiconductor of the present invention, since (E) silicon carbide is previously kneaded with (B) phenol novolac resin, (E) silicon carbide coarse particles or aggregates Is not present and has excellent moisture resistance reliability.
Therefore, by sealing with a cured product of such a semiconductor sealing resin composition, in a device such as a fine-pitch semiconductor package, insulation failure such as leakage failure is prevented and reliability is improved. A high resin-encapsulated semiconductor device can be obtained with high yield.

Claims (5)

(A) Cresol novolac type epoxy resin, (B) phenol novolac resin, (C) curing accelerator, (D) silica, and (E) silicon carbide, (D) total content of silica and (E) silicon carbide It is a resin composition for semiconductor encapsulation whose amount is 75 to 90% by mass of the total resin composition,
(D) The silica contains at least crystalline silica (d1) having an average particle size of 10 to 60 μm, and the volume filling rate of (d1) crystalline silica in the resin composition is 25% by volume or more and 50% by volume or less. ,
(E) Silicon carbide is silicon carbide having an average particle diameter of 10 to 80 μm that is heat-treated at 800 ° C. or higher, and the volume filling rate of (E) silicon carbide in the resin composition is 20% by volume or more and 37% by volume. The resin composition for semiconductor sealing which is the following.   The (D) silica further includes crystalline silica (d2) having an average particle diameter of less than 10 μm, which is pulverized by a jet mill method, and the volume filling rate of (d2) crystalline silica in the resin composition is 1 volume. The resin composition for semiconductor encapsulation according to claim 1, which is not less than 10% and not more than 10 vol%.   The resin composition for semiconductor encapsulation according to claim 1 or 2, wherein a volume filling rate of the (E) silicon carbide is smaller than a volume filling rate of the (D) silica.   A method for producing a resin composition for semiconductor encapsulation according to any one of claims 1 to 3, comprising a step of pre-kneading (B) a phenol novolac resin and (E) silicon carbide in advance. For producing a resin composition for use.   The semiconductor sealed with the hardened | cured material of the resin composition for semiconductor sealing in any one of Claims 1-3, or the hardened | cured material of the resin composition for semiconductor sealing obtained by the method of Claim 4. A semiconductor device including an element.