JPH05190582A - Resin sealed semiconductor device and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a resin sealed semiconductor device where resin is prevented from oozing out and which is stable in electrical insulation by a method wherein an adhesive member impregnated with adhesive agent is formed using insulating cloth as filler and provided onto inner leads, and a semiconductor element is bonded to the inner leads through the intermediary of the adhesive member by thermocompression. CONSTITUTION:A semiconductor element is bonded to the inner leads of a lead frame to form a resin-sealed semiconductor device, where the semiconductor element 3 is fixed to the inner leads 2 through the intermediary of an adhesive member 4, and the adhesive member 4 is formed of an insulating cloth 5 impregnated with adhesive agent 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for fixing a semiconductor element to an inner lead of a lead frame of a resin-sealed semiconductor device.

[0002]

2. Description of the Related Art Conventionally, as a technique in such a field,
For example, there is one as shown in JP-A-64-33939. Various thermoplastic or thermosetting resins are used as the base resin of the adhesive of such a conventional semiconductor device, specifically, polyphenylene sulfide, aromatic polyester, polyether sulfone, polyamide imide, polyimide. It is possible to use a thermoplastic resin such as or a thermosetting resin such as an epoxy resin, a silicon resin, or a polyimide resin.

Further, the filler compounded in the base resin is
As the inorganic filler, fine powder of glass, silica, alumina, zircon or the like is melted in a high-temperature flame and spherically shaped by its surface tension. As the organic filler, spherical fine powder such as polyvinyl carbazole obtained by suspension polymerization, phenol resin, epoxy resin and polyimide resin is used. The filler can be blended in any ratio to the base resin, but from the viewpoint of workability and adhesiveness, it is 10
The range of ˜80% by volume is desirable. The filler is mixed with the base resin by mechanically stirring and mixing at room temperature or in a heat-melted state or in a varnish state dissolved in an organic solvent, depending on the properties of the base resin. Application of the obtained adhesive to the lead frame is carried out at room temperature or at a temperature higher than the melting temperature of the adhesive, depending on the properties of the adhesive. When an adhesive using a thermosetting resin as a base resin is applied to a lead frame at a high temperature, the curing reaction of the resin proceeds and the adhesive loses its function. is necessary.

After the lead frame is coated with the adhesive in this manner, the lead frame is heated again to a temperature higher than the melting temperature of the adhesive to quickly fix the semiconductor element at a predetermined position, and the thermoplastic adhesive is used. If it is, cool it down,
When a thermosetting adhesive is used, the semiconductor element can be bonded to the lead frame by cooling after the curing reaction of the resin is completed.

It is conceivable to apply an adhesive agent to the back surface of the semiconductor element in advance and adhere it to the inner leads. However, the adhesiveness between the encapsulating resin and the adhesive agent is the adhesive property between the encapsulating resin and the semiconductor element. Compared with, the adhesiveness between the sealing resin and the adhesive is considerably inferior, and when such a method is used,
As in the conventional case where an insulating film or sheet is used, a gap is likely to occur between the inner leads, and it is difficult to obtain a sealed product having various characteristics.

[0006]

As described above, in the above-mentioned conventional technique, the semiconductor element is bonded to the inner lead of the lead frame by the thermoplastic or thermosetting resin adhesive containing the filler. However, there is a problem that the resin component of the adhesive oozes out to the back surface of the inner lead and the like, the back surface of the inner lead becomes unstable, and the bonding becomes unstable when clamping in the wire bonding process.

Further, since the granular filler is mixed, the width of the inner lead is extremely narrow when the semiconductor element is moved minutely when the semiconductor element is fixed. Therefore, the granular filler is displaced from the main surface of the inner lead. In some cases, they did not exist on the inner leads, so that a constant interval was not maintained, and there was a problem in electrical insulation. The present invention eliminates the above-mentioned problems, forms an adhesive member impregnated with an adhesive using an insulating cloth as a filler, and arranges the adhesive member on the inner lead, so that the semiconductor element is fixed by heating and pressing. It is an object of the present invention to provide a resin-encapsulated semiconductor device in which resin bleeding is reduced and electrical insulation is stabilized, and a method for manufacturing the same.

[0008]

To achieve the above object, the present invention provides a resin-sealed semiconductor device in which a semiconductor element is fixed to an inner lead of a lead frame, the semiconductor element being fixed to the inner lead. The adhesive member is provided with an impregnated member and an adhesive with which the impregnated member is impregnated.

In the method of manufacturing a resin-sealed semiconductor device in which a semiconductor element is fixed to the inner lead of the lead frame, an adhesive member is arranged on the main surface of the inner lead when fixing the semiconductor element to the lead frame. Then, the semiconductor element is pressed or fixed by softening or melting with heating gas.

[0010]

According to the present invention, in a resin-sealed semiconductor device in which a semiconductor element is fixed to a lead frame from which islands are removed, an insulating cloth is impregnated with an adhesive (adhesive resin) on the inner surface of the inner lead inner end. An adhesive member is placed, the semiconductor element is pressed and fixed, the adhesive resin is heated and melted, and the semiconductor element is fixed to the inner surface of the inner lead inner end.

Therefore, as in the conventional case, when the semiconductor element is fixed, the adhesive flows out to the lower side of the inner lead by the pressing step of the semiconductor element while the adhesive is softened or liquefied to the lower side of the inner lead. It is possible to prevent the formation of the protrusion.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a main portion showing a mounting state of a semiconductor element on a lead frame showing an embodiment of the present invention (A- in FIG. 3).
2 is a sectional view of a resin-encapsulated semiconductor device showing an embodiment of the present invention, FIG. 3 is a plan view of a resin-encapsulated semiconductor device showing an embodiment of the present invention, and FIG. FIG. 5 is a view showing an insulating cloth of a semiconductor device, and FIG. 5 is a sectional view of an adhesive member in which the insulating cloth is impregnated with an adhesive.

Here, the external dimensions of the package are
As a technique for maintaining a standard size and mounting a large-sized semiconductor element, a mounting technique in which an island of a lead frame which is generally used for a resin-sealed semiconductor device is deleted is used. As shown in these figures, 1 is a lead frame, 2 is
Is an inner lead thereof, 3 is a semiconductor element, 4 is an adhesive member, and is composed of two layers of insulating cloth 5, for example, glass fiber cloth (woven cloth) and adhesive 6.

As described above, as the adhesive member 4 for fixing and mounting the semiconductor element 3 on the main surface of the inner lead 2 used as a substitute for the island, for example, the insulating cloth 5 as shown in FIG. The adhesive member 6 is formed by impregnating it with the adhesive 6 as shown in FIG. Although the insulating cloth 5 is formed in two layers, it may be formed in one layer.

The adhesive 6 may also be a thermoplastic resin or a thermosetting resin. In this case, the B-staged thermosetting resin is suitable. The resin as the adhesive 6 is not limited as long as it has a fixing function.
If the thickness of the adhesive member 4 is such that the semiconductor element 3 can be fixed and that the softened or liquefied adhesive does not exude or fall to the lower side at the time of heating and pressing fixation, It is not particularly limited.

Regarding the fixing conditions, for example, when an epoxy resin is used as the adhesive, the gas heated to around 100 ° C. is singulated on the inner leads 2 to separate the adhesive member 4.
Is placed, the heating gas is blown, the adhesive 6 is softened or melted and liquefied, and the semiconductor element 3 is pressed and fixed. Then, it is completely solidified and adhered in a constant temperature bath at about 150 ° C. Generally, N ₂ gas is used as the heating gas. The solidifying conditions are not limited, and may not be a constant temperature bath and may be fixed by heating gas and solidified at the same time.

The cloth may be specially woven into a mesh or plain woven, and the weaving method is not limited.
Further, it may be a non-woven fabric. The thickness of the cloth is 0.1-0.5
The impregnation ability of the adhesive may be increased by stacking several single layers each having a thickness of about mm. Instead of the cloth, a sponge-like member may be impregnated with an adhesive to be used for fixing the semiconductor element. As for the sponge-like member, a metal ultrafine wire can be used after being subjected to a surface non-conductor treatment. Heat dissipation (heat transfer)
It has good properties and is suitable for mounting high frequency semiconductor elements. Since the size of the semiconductor element is increasing, the sealing area and the semiconductor element are mounted to about the same level. You can prevent it from coming out,
It is possible to prevent external moisture and impurities from entering.

As shown in FIG. 3, the inner lead 2
Is connected to the pad of the semiconductor element through the thin metal wire 7, and the semiconductor element 3 is sealed with the sealing resin 8.
In addition, the above embodiment is based on COL (chip on lead).
However, as shown in FIG. 6, a LOC (lead-on-chip) type may be used. That is,
When the semiconductor element 13 is fixed below the inner lead 12 of the lead frame 11, the semiconductor element 13 is fixed via the adhesive member 14 in which the insulating cloth 15 is impregnated with the adhesive 16. The semiconductor element 13 is sealed with the sealing resin 18.

Therefore, although not shown, the adhesive 16 does not seep out and the inner lead 12 and the pad of the semiconductor element 13 can be connected well. It should be noted that the present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

[0020]

As described above in detail, according to the present invention, the inner lead of the lead frame from which the island is removed is impregnated with the insulating cloth to fix the semiconductor element. When fixing the semiconductor element, the adhesive flows out to the lower side of the inner lead by the pressing step of the semiconductor element while the adhesive is softened or liquefied to the lower side of the inner lead as in the conventional case, and the protrusion is formed. Can be prevented.

Therefore, it is possible to reduce the occurrence of defects in the wiring process using the fine metal wires in the subsequent process. In addition, since the bonding process is a small-sized bonding member, the handling is easy and the work efficiency can be improved. Furthermore, the electrical insulation can be improved and stabilized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing a mounting state of a semiconductor element on a lead frame showing an embodiment of the present invention.

FIG. 2 is a sectional view of a resin-encapsulated semiconductor device showing an embodiment of the present invention.

FIG. 3 is a plan view of a resin-encapsulated semiconductor device showing an embodiment of the present invention.

FIG. 4 is a diagram showing an insulating cloth of a resin-sealed semiconductor device showing an embodiment of the present invention.

FIG. 5 is a cross-sectional view of an adhesive member in which an insulating cloth of a resin-encapsulated semiconductor device according to an embodiment of the present invention is impregnated with an adhesive.

FIG. 6 is a cross-sectional view of a resin-encapsulated semiconductor device showing another embodiment of the present invention.

[Explanation of symbols]

 1, 11 Lead frame 2, 12 Inner lead 3, 13 Semiconductor element 4, 14 Adhesive member 5, 15 Insulating cloth 6, 16 Adhesive 7 Metal fine wire 8, 18 Sealing resin

Claims (5)

[Claims] 1. A resin-sealed semiconductor device having a semiconductor element fixed to an inner lead of a lead frame, the adhesive member fixing the semiconductor element to the inner lead, the adhesive member comprising: A resin-encapsulated semiconductor device comprising an impregnated member and (b) an adhesive with which the member to be impregnated is impregnated. 2. The resin-encapsulated semiconductor device according to claim 1, wherein the impregnated member includes glass fiber or glass woven cloth. 3. A method of manufacturing a resin-sealed semiconductor device, comprising a semiconductor element fixed to an inner lead of a lead frame, comprising: (a) fixing the semiconductor element to the lead frame and mounting the semiconductor element on a main surface of the inner lead. A method of manufacturing a resin-encapsulated semiconductor device, which comprises disposing an adhesive member, and (b) softening or melting the same with a heating gas to press and fix the semiconductor element. 4. The method for manufacturing a resin-encapsulated semiconductor device, wherein the adhesive member is obtained by impregnating a cloth with an adhesive and processing the individual pieces by a cutting method such as pressing. 5. The method for manufacturing a resin-sealed semiconductor device, wherein the adhesive member is a heat conductive adhesive member obtained by impregnating an insulating non-woven metal fine wire nonwoven fabric with an adhesive.