JPS61254619A - Epoxy resin composition for encapsulation of semiconductor - Google Patents

Abstract

PURPOSE:To provide the titled composition exhibiting extremely high fluidity in the forming of a semiconductor device, giving little burr, and capable of forming a molded article having low thermal expansion coefficient, by adding a quartz filler to a phenol-curable epoxy resin at a specific ratio. CONSTITUTION:The objective composition can be produced by compounding (A) 100pts. (wt.) of a phenol-curable epoxy resin with (B) 100-500pts. of a quartz filler composed of (i) 20-99% spherical quartz powder having an average particle diameter of 1-25mum and (ii) 1-80% fine quartz powder wherein the powder having particle diameter of <=1mum accounts for >=90%. Preferably, the component A is composed of an epoxy resin having >=2 epoxy groups in one molecule and a phenolic hardener (e.g. phenol novolac), and the component (i) is powder produced by melting quartz powder in a flame of combustible gas and oxygen gas.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides an epoxy resin composition for semiconductor encapsulation, in particular, which exhibits extremely high fluidity during semiconductor device molding, has little generation of flakes, and has a low thermal expansion coefficient. The present invention relates to an epoxy resin composition for semiconductor encapsulation that provides small molded products.

(Prior art) Various types of resins for semiconductor encapsulation are already known, and K uses compositions based on epoxy resins, silicone resins, diallyl phthalate resins, phenol resins, polyphenylene sulfide resins, etc. However, phenol-curable epoxy resins are most commonly used due to their moisture resistance, mechanical properties, productivity, and cost.

However, the dimensions of recent low-pressure transfer molding molds have become larger as the number of cavities has increased, and when semiconductor devices are molded using such molds, some parts may not be filled with resin. Since there is a risk that an accident may occur, this sealing tree jliiJlfL composition is required to have good fluidity.

7) For phenol-curing epoxy 81 resins, l) Use resins with low melt viscosity or mix low-molecular-weight diluents. 2) Reduce the amount of curing catalyst. 3) Reducing the amount of inorganic filler has been proposed, but
Although method 1) improves fluidity, it often causes cracks during molding11, and if a diluent is used, smudges appear on the surface of the molded product, and the volatile content increases, resulting in large dimensional changes. In addition, k has the disadvantage that the aluminum wiring corrodes more quickly. Also.

In method 2), the curability of the resin composition deteriorates, so if it goes against the demand for rapid curing in order to improve productivity, there is a disadvantage in method 3). The coefficient and stress are large (as a result, crack resistance is reduced), and the force applied to the aluminum wiring and passivation film on the surface of the silicon chip is also large.

In addition, it is known that spherical quartz powder is used as an inorganic filler in this epoxy resin composition, and this is because adding spherical quartz reduces stress. Average particle size is 1
30-80 frii% of ~6011m spherical fused silica
It has also been proposed to add
(Refer to Publication No. 40) However, since this K does not have sufficiently satisfactory fluidity, there are problems such as underfilling occurs when a larger mold is used, and resin leakage and flaking occur frequently. .

(Structure of the Invention) The present invention relates to an epoxy resin composition for semiconductor encapsulation that can solve the above-mentioned disadvantages.
100 parts by weight of a phenol-curable epoxy resin, 2) 20-99% by weight of spherical quartz powder with an average particle size of 1-25 μm;
Quartz filler 10 consisting of fine quartz powder 1 to 80 [31%] of which 90% by weight or more is powder with a particle size of 111 m R or less
0 to 500 parts by weight.

In other words, the present inventors have conducted various studies on epoxy resin compositions for semiconductor encapsulation that have high fluidity (and less generation of paris), and have found that quartz powder is used as an inorganic filler added to the epoxy resin. found that when this quartz powder contains fine quartz powder with a particle size of 1 μm or less, the fluidity increases and the occurrence of paris can be reduced. According to K, 1% or more of 9oi should have a particle size of 1 μm or less, and this should be used by mixing it with spherical quartz powder having an average particle size of 1 to 25 μm. We confirmed that it was possible to reduce the coefficient of thermal expansion of molded products made from this composition by allowing high filling of quartz powder, and conducted research on the type of quartz powder to be used and the blending ratio. We proceeded to complete the present invention.

Next, each component constituting the composition of the present invention will be explained.

First, the phenol-curable epoxy resin as the first component used in the present invention is a curable epoxy resin consisting of an epoxy resin having two or more epoxy groups in one molecule and a phenolic curing agent, This material is not particularly limited in its molecular structure and molecular weight as long as it can be cured with the phenolic curing agent described later, and various conventionally known products can be used, such as epichlorohydrin. Examples include epoxy resins synthesized from various novolac resins such as and bisphenol, alicyclic epoxy resins, and epoxy resins into which halogen atoms such as chlorine and bromine are introduced. There is no problem in appropriately using a monoepoxy compound in combination with this epoxy resin; examples of the monoepoxy compound include styrene oxide-cyclohexene oxide, propylene oxide, methyl glycidyl ether, ethyl glycidyl ether, and phenyl glycidyl ether.

Allyl glycidyl ether-octylene oxide.

Examples include dodecene oxide.

In addition, various conventionally known phenolic curing agents can be used, and examples of K include those having two or more hydroxyl groups in each K molecule, such as phenol novolac and cresol novolac. can.

The epoxy resin may contain various curing accelerators 1, such as imidazole or its derivatives, tertiary amine derivatives, and phosphine derivatives, for the purpose of promoting the reaction between the above-mentioned curing agent and the epoxy resin.

It is optional to use a cycloamidine derivative or the like in combination.

Next, the quartz-based filler as the second component used in this composition is made of spherical quartz having an average particle size of 1 to 25 μm and 90% by weight or more of fine quartz powder having a size of 1 μrrL or less.

This spherical quartz with an average particle size of 1 to 25 μm has an aspect ratio of 1 to 1.3, and is produced by mixing synthetic or natural quartz powder with combustible gas such as hydrogen or glopane and oxygen gas. It may be obtained by melting in a flame using a silane, by hydrolyzing monotetraethoxysilane or tetramethoxysilane, or by sintering or melting after hydrolysis.

In addition, this fine quartz powder may be obtained by crushing a natural or synthetic quartz lump, or by further classifying it after crushing. % or less, the epoxy resin composition to which it is added will not have sufficiently satisfactory fluidity, and further K will cause resin leakage and flaking (because it will become 90!
It is necessary that at least % of the particles have a particle size below 1 pWLa.

When the blending ratio of the above-mentioned spherical quartz and fine quartz powder in this second component is such that the fine quartz powder is less than 1% by weight of the total weight, the purpose of improving fluidity and reducing paris in the epoxy resin composition of the present invention is achieved. figure.

If the content is more than 80% by weight, molded articles made from this composition will be prone to resin cracks, so it is necessary to contain 1 to 80% by weight of fine quartz powder.

The amount of the quartz filler as the second component is the same as the first component.
100 parts by weight of epoxy resin as a component
If the weight is less than the weight, the molded product made from this composition will have a large coefficient of linear expansion and its crack resistance will not be satisfactory.

If it exceeds 500 parts by weight, the dispersibility in the epoxy resin will be poor, and the fluidity of the composition will also be poor, so it needs to be in the range of 100 to 5001 parts by weight, but the preferred range is 200 to 5001 parts by weight. The amount is 350 parts by weight.

The epoxy resin composition of the present invention is produced by uniformly mixing predetermined amounts of the first and second components described above.

However, the surface of this quartz-based filler may be treated with carbon functional silane or the like in advance, and if necessary, various additives 1, such as pigments such as carbon black, Mold release agents and flame retardants such as natural straw.

Flexibility imparting agents such as organopolysiloxane and block copolymer-modified polybutadiene of organopolysiloxane and phenol novolac resin.

Carbon functional silane or the like may be added.

Next, examples of the present invention will be given, and the part in each example indicates the active part, and the physical property values in each table show the test results according to the following method.

l) Powder of spiral flow epoxy resin composition 20. F, EMMI-1-
The values were measured when molding was performed using a mold according to No. 66 at a mold temperature of 175°C and a plunger pressure cuff of 0 Kt/-.

2) Resin leakage, Paris epoxy resin composition powder 2 (l, 10 μm 30 μm
The mold temperature was set to 17 using a Paris measurement mold with a slit of
Molding was carried out at 5° C. with a plunger pressure cuff of 0 Kf/−, and the length of the resin leaking into the slit at this time was measured with a caliper.

3) Thermal expansion coefficient The epoxy resin composition was molded at 175°C for 2 minutes.
igmp
The thermal expansion coefficient was measured from 25° C. to 120° C. using a product manufactured by Shinku Goka Co., Ltd. (trade name).

4) Flexural modulus The epoxy resin composition was molded at 175°C for 2 minutes at 11
It was molded into a 00x10x4 resistance bar, after-cured at 180°C for 4 hours, and then its flexural modulus was measured according to the method of JI8/6911.

5) Crack resistance test 9, 40 silicon chips of OX4.5x0.5m
4PXNIO frame) and molded the epoxy resin composition on it at 175°C for 2 minutes.
After cure for 4 hours at -196°C (1
A temperature cycle test of 1 minute) to +300°C (1 minute) was conducted, and the resin crack occurrence rate after 10 cycles was measured.

Examples 1-3. Comparative Examples 1 to 3 Cresol novolac type epoxy resin/EON-127
0 (trade name manufactured by Chipa Co., Ltd.) 600 parts, phenol novolac resin TD2093 (trade name manufactured by Dainippon Ink Co., Ltd.) 300 parts
quartz filler and silicone oil-modified epoxy resin (silicone modification rate 30%) in the amounts shown in the table.
0 parts, 10 parts of triphenylphosphine, 10 parts of carnauba wax, 100 parts of antimony trioxide, 10 parts of γ-glycidoxyglobyltrimethoxysilane, and 10 parts of carbonbrasof were blended in a Henschel mixer. Six types of phenol-curable epoxy resin compositions were prepared by kneading them in an extruder, cooling and pulverizing them1).Then, when the physical properties of these K were investigated, the results shown in Table 2 were obtained. .

Examples 4-7. Comparative Examples 4-5 Cresol novolac type epoxy resin/KOCN102
(Product name manufactured by Nippon Kayaku Co., Ltd.) 650 parts, Phenol novolak resin TD2093 (300 parts of the above mentioned product), Professional epoxy resin YDB 340 (Product name manufactured by Tobu Kasei Co., Ltd.) 50
quartz-based filler in the amount shown in Table 3 and Examples 1 to 3.
The same types and amounts of curing catalyst, mold release agent, and silane coupling agent as those used in were mixed and treated in the same manner as above to prepare six phenol-curable epoxy resin compositions and the physical properties thereof were determined. The results shown in Table 4 were obtained.

Claims (1)

[Claims] 1.1) 100 parts by weight of a phenol-curing epoxy resin 2) 20-99% by weight of spherical quartz powder with an average particle size of 1-25 μm, and 90% by weight or more of powder having a particle size of 1 μm or less An epoxy resin composition for semiconductor encapsulation, comprising 1 to 80 parts by weight of fine quartz powder and 100 to 500 parts by weight of a quartz filler.