JPS5923403A - Synthetic silica and a resin composition for encapsulating electronic components containing the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to synthetic silica, particularly synthetic silica and resin composition suitable as fillers for resin compositions for encapsulating electronic components.
The present invention relates to a resin composition for encapsulating electronic components containing e.

Electronic components are generally sealed with a ceramic package or resin to protect them from the external environment, but synthetic resin compositions are commonly used as sealing materials due to cost and productivity. This dangerous resin composition is composed of an organic resin and an inorganic filler mainly composed of silica. As this inorganic filler, a silica-based filler is most preferable. Silica-based fillers are used in this process. These silica-based fillers are broadly classified into crystalline and non-crystalline types, each of which has advantages and disadvantages, and can be used depending on the purpose and application.
ing.

Conventionally, silica-based fillers are made by powdering natural ores without refining them, or by washing the natural ores with water and treating them with acid, then sintering or melting them at a temperature of 1,000 to 1,800 degrees Celsius, and then pulverizing them. Quartz powder is used.

However, with regard to memory elements sealed with this type of resin composition, a. There is a problem in that the memory element malfunctions due to the wires, so a solution to this problem is desired. Therefore, the silica-based filler used in this memory element sealing resin composition is made of various synthetic silicas currently on the market, such as dry silica obtained by flame hydrolysis of silica tetrachloride, and hydrated sodium silicate. The use of synthesized wet silica by neutralizing it with hydrochloric acid has also been considered; BET method) is also 50t
r? It is known that such substances cannot be filled into organic resins in large quantities and therefore cannot be used in resin compositions for encapsulating electronic components.

In addition, the above-mentioned wet silica is unsuitable in terms of purity, as it is nearly impossible to remove the alkali ions remaining in the process before the process is completed, which is required as a filler for resin pots for sealing electronic components such as conductors. It is.

In addition, synthetic silica can be made by crushing synthetic quartz, but compared to the dry silica described above, this requires a melting and vitrification process, so it requires a large amount of hydrogen and heat energy. Since synthetic quartz ingots are vitrified, they are very hard and difficult to pulverize, and when pulverizing them, avoid contamination and contamination with foreign substances. There is a disadvantage of not being able to do so.

That is, high-purity silica suitable for encapsulating electronic components and capable of being highly filled does not currently exist and is difficult to obtain.

The present invention relates to a resin composition for encapsulating electronic components containing synthetic silica, which can be used as a resin composition for encapsulating electronic components, which can overcome the disadvantages of the above. ), and n are finely powdered silica synthesized from a distilled and purified silicon compound having a hydrolyzable group, formed into aggregates or lumps, and then heated at a temperature of 1000 to 1
A first invention relating to synthetic silica fired at 800°C, and a resin for encapsulating electronic components, which is obtained by adding 50 to 800 parts by weight of the synthetic silica of the first invention to 100 parts by weight of a thermosetting resin or thermoplastic resin. This invention is different from the second invention regarding the composition.

and n, the inventors found that the average particle diameter is 1 mμ
As a result of extensive research into the use of extremely fine powdered silica of ~100 mμ as a filler in resin compositions for encapsulating electronic components, we have found that the fine powdered silica has been granulated into aggregates with a size of 1 μm to several micrometers. After making a lumpy plastic material by adding liquid such as water or kneading it, and lrL
! The present invention was completed by discovering that silica powder having an average particle size of 1 μm to 100 μm can be produced by firing at a temperature of −1000 to 1800° C.

As the silicon compound used as the starting material for making the silica of the first invention, for example, the formula RtSi, ¥4
-4 (wherein R is a hydrogen atom or a -valent hydrocarbon group, X is an atom or group having hydrolyzability, and t is O~3), or one or two of the silane compounds Examples of siloxane compounds obtained by hydrolyzing the above compounds include tetrachlorosilane (
St C1, ), trichlorosilane (H8t CIB
), methyltrichlorosilane (CHB Sic I
B), dimethyldichlorosilane 7C(CHa)IS
jC! f ), tetramethoxysilane [S i (OC
Hs ) number] Methyltrimethoxysilane [CB, S (
OCHs)3], off-con can be used alone or as a mixture of two or more thereof.

Various methods can be used to synthesize fine powdered silica using all the silicon complexes mentioned above. For example, after hydrolyzing a purified silicon compound by a conventional method ( The method described by Tan et al. It is particularly suitable for organic group-containing silicon compounds that cannot be removed by wet methods.

In addition, the fine powdered silica obtained by the method of et al. is extremely fine with an average particle size of 1 μm or less and has a small bulk density, so it is easy to scatter even when batch firing. It is difficult to handle because it is easily charged with static electricity, and requires a large-capacity kiln because its bulk specific gravity is small, and it also has the disadvantage of poor efficiency due to its low thermal conductivity.

In order to solve this problem, it is necessary to mold (granulate) fine powder into granules or lumps. It is effective to fire it later.

This molding (granulation) method includes conventionally known methods such as transfer type granulation method, fluidized bed type granulation method, extrusion type granulation method, compression type granulation method, crushing type granulation method, A jet granulation method or the like can be adopted. The simplest method is to add an appropriate amount of water to finely powdered silica, knead it, spread the resulting plastic material uniformly on a flat plate, solidify it into a thick plate, and then apply lrL as appropriate. There are several methods for pulverizing the material to a suitable size.

The amount of water added at this time varies depending on the particle size of the fine powder/crisp, but generally it is 1 part by weight per 100 parts by weight of silica.
The amount is preferably 0 to 600 parts by weight. If the water content is low, it will not be possible to obtain a sufficient degree of caking, but if the water content is excessive, it can be poured into a container such as a slurry.

However, using more water than necessary is pointless as it only delays drying.

In this way, fine powdered silica can be easily aggregated by adding water, and its bulk can also be reduced. For example, humid silica usually has a bulk density of α05f/c
m'', but by kneading it with about 3 times the amount of water, it shrinks to ~%.

Further, by air drying this mixed wire, it can be further shrunk to [+4]. In this way, 10 times the bulk density of fumed silica can be made into any granular or lumpy form, resulting in a throughput of 10 times the bulk density of the silica during the firing process.
It will be K so that the improvement can be more than doubled.

The grains or lumps obtained by K as described above are air-dried or
Dry at a temperature of 0°C or lower, or leave as is at a temperature of 1000 to 1800°C, preferably 1200 to 16°C.
Fire at 00°C. If the temperature is lower than 1000°C, sufficient coagulation between the particles will not be achieved, and if the temperature is higher than 1800°C, the whole will melt until it becomes one piece, making the next process difficult! ! This is because a higher temperature than necessary is disadvantageous in terms of heat costs.

When firing under these conditions, it is possible to obtain particles ranging from fine powders of about 1 to 1 μm to lumps of several α or more, but larger particles must be crushed and classified. It can be obtained as a synthetic silica suitable for use in sealing resin compositions.

Note that if the crystallization temperature range is passed for a short time, amorphous silica will be produced, and if the crystallization temperature range is passed for a long time, then the crystallized silica will be produced.
It is possible to obtain crystalline synthetic silica having Itowo as its main component, and it is also possible to obtain silica with high thermal conductivity.

Furthermore, when it is desired to obtain synthetic silica with a low halogen content, it is sufficient to use a halogen atom-free material such as tetraethyccumulane as a starting material.

The resin composition for encapsulating electronic components as the second aspect of the present invention is obtained by distributing the synthetic sliding force of 2 to a thermosetting resin or a thermoplastic resin. Materials used for sealing may be used, such as thermosetting resins such as epoxy resins, silicone resins, epoxy silicone resins, and polyimide resins, and thermoplastic resins such as polyphenylene sulfide resins. nru.

The resin composition for encapsulating electronic components of the present invention is obtained by blending the above-described organic resin and the above-described synthetic silica. The amount of synthetic silica to be added is preferably as large as possible from the viewpoint of keeping the expansion coefficient of the composition low and providing good heat dissipation properties. There is a risk of worsening the moldability or deteriorating the mechanical properties, and if the amount is less than 100 parts by weight, the effect will not be fully achieved. Quartz powder 50-8
00 parts by weight, particularly in the range of 100 to 500 parts by weight.

This composition may contain various additives, such as colorants and flame retardants, as required.1. An m-type agent may be added.

The above-mentioned resin composition of the present invention is molded into an appropriate shape after being blended, and electronic components can be sealed using any of conventionally known injection molding, injection molding, compression molding, and transfer molding. However, it is possible to easily obtain a resin-sealed electronic component that is completely free from soft errors due to the emission of NA radiation.

Next, examples of the present invention will be given, and all parts in the examples indicate parts by weight.

Example 1 H8 and O2 are placed in a burner with a triple tube structure, 1"L4
t/min, 2t/min to form an oxyhydrogen flame, and 5iC1,f gaseous state is supplied to the center of this flame, (supply amount 500
d/min) flame hydrolysis was carried out to produce a fine powder of 7 liters. This fine powder was collected by depositing it on a heat-resistant substrate. In this case, the fine powder silica has an average particle size of about 0.2 μm.
It was m.

520 parts of water was added to 000 parts of this finely powdered Kurikani to form a slurry, which was poured into a square vat and air-dried for 3 days.
A plate-like product with a thickness of about 1 m was obtained.

After pulverizing this into a cube-shaped lump with a side of 2 to 2 cm and as small as this, he joined Matsufuru Furnace.
When firing was performed at 400° C. for 1 hτ, a dense glass-like sintered body was obtained. When the powder was pulverized in an agate mortar, a synthetic silica powder with an average particle size of 20 μm was obtained.

Next, cresol novolak epoxy resin (trade name EccN102) was added to 300 parts of the synthetic silica powder obtained above.
100 parts, phenol novolak resin (trade name TD20
93) An 8-inch roll of a handout prepared by adding and blending 50 parts of 2-phenylimidazole, 1 part of 2-phenylimidazole, 2 parts of carnauba wax, 2 parts of carbon black, and 1 part of siglobiltrimethoxysilane in 3-glyzide was heated to 80°C. After kneading for 5 minutes, the mixture was taken out in the form of a sheet and pulverized to obtain a resin composition for encapsulating electronic parts.

Example 2 Ethyl silicate was added dropwise to deionized water in the presence of a catalytic amount of ammonia with stirring. The resulting gel-like hydrolyzate was thoroughly washed with deionized water and then dried to obtain a gel powder. 1,850 parts of water was added to 1,000 parts of the gel powder, extruded into a rod shape with a diameter of about 10 pieces, and the product was placed in a Matsupuru furnace and fired for 1 h at 1,400°C to obtain a porous glass-like sintered body. When ground in an agate mortar, synthetic silica powder with an average particle size of 8 μm was obtained. The halogen content in this synthetic silica powder was determined to be 27 parts % or less. A resin composition for encapsulating electronic components was obtained having the same composition as in Example 1 except that this synthetic silica powder was used as a filler.

Example 3 In place of the synthetic silica fine powder of Example 1, commercially available Humid 7 Lika (trade name, 1urosi1380) was used. :,used. This humid silica (apparent specific gravity QO586f/
Add 450 parts of water to 100 parts of cc), mix well, and -
When the mixture was molded into a block with a diameter of 34 m and air-dried, the volume shrunk to form a block with a diameter of 25 cm. The volume of this lump shrank to the volume of the compact, and the apparent density was α574 t/yn''. This means that
Compared to fumed silica, which has a bulk density of 1059/cm, the throughput in a firing furnace of the same volume is improved by about 10 times, indicating that productivity is improved.

After the above-mentioned air-drying, the 7-reinforced mass was fired for 1 hour at 11,300° C., and a glass-like sintered body was obtained. This,
When crushed in an agate mortar, the average particle size was 13 μm.
A synthetic silica powder was obtained.

A resin composition for encapsulating electronic components was obtained having the same composition as in Example 1 except that this 2"L was used as a filler.

Example 4 307 parts of water was added to 1173 parts of humid silica (Aarosi200), moistened well, and made into 20 tablets of φ x 115 m using a tablet machine, and then heated at 60°C.
After drying for 24 hours at 1300° C. for 1 hour, a granular sintered body was obtained. This was pulverized to obtain a synthetic 7 licorice powder. The average particle size of this product is 5
It was μm.

A resin composition for encapsulating electronic components was obtained having the same composition as in Example 1 except that it was used as a filler.

Example 5 100 parts of water was added to 100 parts of humid silica (Agros (J200)) and mixed well. Although this product had an apparent volume of approximately 'AK, it was still powdery and could not be molded.

This rL was calcined at 1350° C. for 3 hours, and the crystal form f was examined using a cooling layer and X-rays. The results showed a sharp peak indicating the presence of crystals. This n was not found in Examples 1 and 2°3.4. When this powder was heated again to 1,600°C and then cooled to room temperature, no crystals were observed.

The properties of the resin compositions obtained in Examples 1 to 4 above are shown in Table 1 below.
and shown in Table 2.

Table 1 Content of uranium and thorium and α-ray intensity (p p b) 2 Resin properties example 1 2 3 4 (Imp curve tj' strong F!wF4/z") a5 140
′1゛B, ρ a.

Volume resistivity (0,6R) α5X10'i LOX10'
4α3 XIO'Aα3X10'easy (150℃) Procedural amendment 1. Display of the case 1982 Patent Application No. 133249 2° Invention 0 Title Synthetic silica and resin composition for electronic parts containing the same 3, person making amendment Relationship with the case Patent applicant name (206) Shin-Suzuki Kagaku Kogyo Co., Ltd. 4, Agent Address: Nagai Building, 4-9 Nihonbashi Honmachi, Chuo-ku, Tokyo 103 [Telephone Tokyo (270) 085 g, 085
9] 6. Specification subject to amendment 7, contents of amendment As per attached sheet (1) 3 lines from the bottom of section 10 to 4, ``In addition to melting until the whole becomes integrated, the next process will be difficult.''``Yuiga,'' he corrected.

(1 fading of color in 5 lines of 11th picture of 21) is corrected to "pass".

13+ Change “100 vehicle volume” on page 12, line 12 to “50
Corrected as ``Vehicle volume section''.

that's all

Claims (1)

[Scope of Claims] L Synthetic silica obtained by molding fine powder silica synthesized from a silicon compound having a hydrolyzable group purified by distillation into aggregates or lumps, and then firing at a temperature of 1000 to 1800°C. 2 Synthetic silica has a uranium and thorium content of 1
Synthetic silica a according to claim 1, which has an average particle diameter of 1 to 100 μm and has an average particle diameter of 1 to 100 μm. The silicon compound having a hydrolyzable group purified by distillation is substantially free of halogen atoms. The synthetic silica powder according to claim 1, wherein the fine powder silica has a large surface area, and the calcination temperature is L100 to L500°C. An electronic component comprising 100 parts by weight of a curable resin or thermoplastic resin and 50 to 800 parts by weight of the synthetic silica f described in any one of claims 4 to 3 above. Sealing resin composition