JPH08239557A - Semiconductor encapsulation equipment - Google Patents

Abstract

(57) Abstract: Provided is a semiconductor encapsulation device excellent in quality stability by using a composition having good workability. SOLUTION: Crystalline epoxy resin, particle size 0.05 to 10
A semiconductor encapsulation device coated with a composition containing 0 μm of fused silica and a curing agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor encapsulation device obtained by coating with a composition having a good melt fluidity and a high curing rate and a good workability.

[0002]

2. Description of the Related Art Conventionally, as one of means for sealing a semiconductor element, there is a method of placing a pellet composition obtained by molding an epoxy resin powder into a predetermined size on a semiconductor element and then heating and melting it to cover it. is there. To perform this inorganic melt sealing,
The epoxy resin powder needs to flow sufficiently after melting,
Therefore, it is necessary to slow the reaction rate of the epoxy resin. Therefore, the following measures have been conventionally taken.

(A) A curing agent having a slow reaction rate is selectively used.

(B) When a curing agent having a particularly slow reaction rate is used, a small amount of the curing agent is used or dry mixing is performed.

However, (a) has a drawback that it takes a long time to cure and the workability is poor, and (b) has a small amount of a curing agent, so that the characteristics of the epoxy resin cured product deteriorate and the dry type is also used. In the case of mixing, the dispersibility is poor and the stability in terms of quality is lacking.

[0006]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to solve the problems caused by the above-mentioned conventional methods, and to use a composition having good workability to seal a semiconductor having excellent stability in terms of quality. It is to provide a stop device.

[0007]

The above object is to use a specific epoxy resin, which is a crystalline epoxy resin, which has never been used in this kind of semiconductor encapsulating composition, as an epoxy resin, and to which an inorganic material is added. It is achieved by using a composition containing a filler and a curing agent as a semiconductor element encapsulating composition.

The crystalline epoxy resin referred to here is
It is a solid epoxy resin in which a large number of crystal peaks appear by X-ray diffraction, has a physically sharp melting point, and has a property of extremely lowering the viscosity because intermolecular interaction is almost eliminated during melting.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The crystalline epoxy resin used in the present invention is a solid crystalline epoxy resin having a melting point of 50 to 150 ° C., and so-called crystalline epoxy resins conventionally used in this kind of field are widely used. Can be used. Particularly in the present invention, an epoxy resin having a melt viscosity of 5 poise or less at a temperature higher by 10 ° C. than the melting point is preferable. Specific examples of these include, for example, 4,4′-bis (2,2
Examples thereof include 3-epoxypropoxy) -3,3 ', 5,5'-tetramethylbiphenyl, diglycidyl terephthalate, diglycidyl hydroquinone and the like. More specifically, for example, diglycidyl hydroquinone represented by the following general formula (1) will be described as a representative example.

[0010]

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Diglycidyl hydroquinone is a compound having the number of repeating units n = 0 in the general formula (1),
It has crystallinity. However, in the present invention, 20% or less, preferably 5% or less, of the compound in which n is about 1 to 5 or the compound in which the terminal is not epoxidized may be contained.

A particularly preferred crystalline epoxy resin is represented by the following structural formula (2). In this epoxy resin, when R is CH ₃ , the melting point is 105 to 107 ° C.
When melted, it exhibits a very low viscosity of about 0.02 poise or more at 150 ° C.

[0013]

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In the present invention, the crystalline epoxy resin having a melting point of 50 to 150 ° C. is used as described above, but if it does not reach 50 ° C., the target powder composition will block. Is likely to occur, and conversely 1
If the temperature is higher than 50 ° C, workability tends to deteriorate.
A preferable melting point is about 80 to 120 ° C.

In the present invention, an epoxy resin other than the above crystalline epoxy resin can be used in an amount of 50% by weight or less based on the crystalline epoxy resin, and other resins in this case are, for example, bisphenol A type. Typical examples include epoxy resin, novolac type epoxy resin, and ordinary glycidyl type epoxy resin.

The curing agent used in the present invention is not particularly limited as long as it is a solid curing agent, and examples thereof include diaminodiphenylmethane, dicyandiamide, tetrahydrophthalic unhydride and novolac type phenolic resin. These curing agents can be used alone or in a mixture of two or more.

With respect to the compounding ratio of the epoxy resin and the curing agent, it is preferable that the ratio of the number of functional groups of the curing agent and the number of epoxy groups of the epoxy resin is in the range of 0.5 to 1.5. . At this time, if it deviates from the above range, the reaction becomes difficult to sufficiently occur, and the characteristics of the cured product tend to deteriorate.

In the present invention, a curing accelerator can be used in combination with the curing agent. Specific examples include imidazoles such as 2-methylimidazole and 4-ethyl-2-methylimidazole, tertiary amines such as benzyldimethylamine and triethylamine, boron trifluoride amine complex, tin octylate, and cobalt naphthenate. Examples thereof include salts.

As the inorganic filler used in the present invention, fused silica powder, quartz glass powder, crystalline silica powder, glass fiber, talc, alumina powder, calcium silicate powder, calcium carbonate powder, barium sulfate powder, titanium oxide. Among the powders, quartz glass powder, crystalline silica, and alumina powder are most preferable among them in terms of high purity and low coefficient of thermal expansion. The particle size of these inorganic fillers is usually 0.05 to 100 μm, preferably 0.1 to 30.
It is in the range of μm, and the amount thereof is 150 to 300 parts by weight, preferably 150 to 250 parts by weight, based on 100 parts by weight of the crystalline epoxy resin.

The epoxy resin composition according to the present invention may optionally include, for example, natural waxes, synthetic waxes, metal salts of straight chain fatty acids, release agents such as acid amides, esters or paraffins, and carbon black. Colorants such as the above, silane coupling agents and the like may be appropriately added and blended.

The composition according to the present invention is obtained by thoroughly mixing the raw material components selected in a predetermined composition ratio with, for example, a mixer, and then subjecting them to a melt mixing treatment with a hot roll or a mixing treatment with a kneader or the like and then pulverizing. The powder is provided in the form of powder or by molding the powder into pellets with an arbitrary size by pressing or the like.

The composition according to the present invention can be used not only for encapsulating semiconductors, but also for encapsulating capacitors, resistors and the like, and can also be formed into tablets for molding or other adhesives. it can.

The present invention has been described above by using the pellet composition for semiconductor encapsulation as a typical example thereof. However, in the present invention, not only the case of using the pellet composition but also the powdery molding composition is used. Alternatively, the semiconductor of the present invention may be sealed by various conventionally known sealing means using the composition of the present invention.

[0024]

EXAMPLES The present invention will be specifically described below with reference to examples, but the term "parts" means "parts by weight".

[0025]

Example 1 With the compounding ratio (all parts) shown in Table 1, 4,4'-bis (2 ", 3"-which is a crystalline epoxy resin is used.
Epoxy propoxy) -3,3 ', 5,5'-tetramethylbiphenyl (epoxy resin A: epoxy equivalent 18
5) 100 parts, fused silica powder 180 parts, silane coupling agent A-186 (made by Union Carbide) 2.5
And 1 part of carbon black are premixed with a Hensyl mixer, and sufficiently melt-mixed at 95 ° C. to 100 ° C. with a hot roll, and then phenol novolac resin (softening point 98
C., 57 parts of phenolic hydroxyl equivalent 106) and 0.5 part of 2-undecylimidazole were added, and the mixture was melt mixed for 4 minutes, cooled, and then ground and classified according to a conventional method to obtain a powder of 40 mesh pass. .

The gelation time and curing time of this powder at 150 ° C. were measured by DSC on a 150 ° C. hot plate. After completely curing this powder, TMA (Therma
The glass transition temperature was measured by a mechanical analyzer. The respective results are shown in Table 2.

This powder was heated at room temperature and 100 atm for 1.5 × 8.
1.0 × 5 × 5 by forming into pellets of × 8 (mm)
It was placed on a steel plate of (mm) and sealed in an atmosphere of 150 ° C., and its coating state was evaluated. As a result, good coverage including the edge portion was shown. Furthermore, 0.35 g of this powder was made into pellets with a diameter of 13 mm at room temperature and 100 atm.
The tablets prepared were placed on a degreased polished steel plate (1.0 × 70 × 300 mm, left for 30 minutes or more) installed in a 0 ° C. oven and inclined at 10 °, and the flowability was evaluated by the following formula.

[0028]

[Equation 1]

The results of the above evaluations are shown in Table 2.

Further, an IC package (42-pin DIP) is sealed with the obtained powder and pellets to obtain a semiconductor device, and a thermal cycle test is conducted 50 cycles of 150 ° C. for 10 minutes and −50 ° C. for 10 minutes. Then, those in which no cracks were generated in the device were marked as ◯, and those in which cracks were generated were marked as x.

[0031]

Example 2 In the same manner as in Example 1, the raw material composition ratios (parts) shown in Table 1 were prepared and evaluated. The results are shown in Table 2.

[0032]

Comparative Example 1 In the raw material composition ratio (parts) shown in Table 1,
Bisphenol A type epoxy resin (epoxy resin B, epoxy equivalent 650) which is an amorphous epoxy resin 100
Part, 180 parts of fused silica powder, 2.5 parts of silane coupling agent (A-186), and 1 part of carbon black were premixed with a Hensyl mixer, and then heated with a hot roll to 95 parts.
After sufficiently melt-mixing at 100 ° C to 100 ° C, the mixture was cooled and pulverized by a conventional method, 1 part of 2-undecylimidazole was added, and the mixture was dry-mixed with a Hensyl mixer to obtain a powder. The results are shown in Table 2.

[0033]

Comparative Examples 2 and 3 The raw material composition ratios (parts) shown in Table 1 were prepared in the same manner as in Example 1 and evaluated. The results are shown in Table 2.

[0034]

[Table 1] * 1: Boron trifluoride / ethylamine

[0035]

[Table 2]

[0036]

As is clear from the results shown in Table 2 above, the pellet composition of the present invention has good workability and stable quality.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoshi Saito 1-2-1, Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation

Claims (3)

[Claims] 1. A crystalline epoxy resin, having a particle size of 0.1 to 30.
A semiconductor encapsulation device coated with a composition containing a fused silica powder of μm and a curing agent. 2. The semiconductor encapsulation device according to claim 1, wherein 100 to 300 parts by weight of the fused silica powder is mixed with 100 parts by weight of the crystalline epoxy resin. 3. The crystalline epoxy resin is 4,4′-bis (2 ″, 3 ″ -epoxypropoxy) -3,3 ′, 5,5′-tetramethylbiphenyl represented by the following structural formula. The semiconductor encapsulation device according to claim 1. Embedded image