JP3019046B2 - Lead frame for semiconductor device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lead frame for a semiconductor device and a method for manufacturing the same.

[0002]

2. Description of the Related Art A lead frame used in a semiconductor device will be described with reference to FIG. 1A. Basically, an island 6 for mounting a semiconductor element, a suspension lead 8 for supporting the island 6, A plurality of internal leads 2 disposed in the periphery, an external lead 7 connected to the internal lead 2, and a tie bar 4 for freezing between the external leads 7, 7 in order to prevent resin flowing out during resin sealing. And a frame 5 for supporting these.

In recent years, in response to the increase in the number of pins in semiconductor devices,
The internal leads 2 of the lead frame for semiconductor devices have been extremely miniaturized, and those having a tip width of 100 μm or less have been produced.

For this reason, an adhesive is applied to an insulating film of polyimide or the like so as to prevent deformation of the internal leads 2 generated when handling a lead frame for a semiconductor device and thermal deformation at the time of assembling a semiconductor element and to obtain good bonding. And a plurality of internal leads 2 using a two-layer insulating tape 1 provided with
Are adhered and fixed so that they are connected to each other by the insulating tape 1 across the cross section.

[0005]

As shown in FIG. 3A, the above-mentioned conventional lead frame for a semiconductor device has a thickness of about 50 as an insulating tape 1 connecting the internal leads 2 to each other.
A resin film such as polyimide having a thickness of μm is used as a base, and an acrylic resin layer or the like having a thickness of about 20 μm used as an adhesive 3 with a lead frame is laminated. This is cut into a predetermined shape and thermocompression-bonded to the internal lead to fix the internal lead.

The lead frame to which the internal leads 2 are fixed by the insulating tape 1 as described above may be thermally decomposed when heated to a high temperature in the process of assembling the semiconductor element, and ionic impurities may be released. In addition, ionic impurities are generated due to insufficient purification of the raw material of the adhesive 3 and contamination in the semiconductor element assembling process. In particular, when the resin of the semiconductor element absorbs moisture or when moisture invades from the interface between the lead frame and the resin, the leakage current between the internal leads 2 and 2 causes these ionic impurities to deposit on the adhesive 3. There is a problem that is caused by doing.

A technique for solving this problem is disclosed in Japanese Unexamined Patent Publication No.
No. 33459. JP-A-4-133
In the technique disclosed in Japanese Patent No. 459, an adhesive 3 is applied to one surface of an internal lead 2 as shown in FIG.
In order to adhere the internal lead 2 to the insulating tape 1 with the adhesive 3, in the step of applying the adhesive 3 to the internal lead 2,
Since the internal leads 2 are in a free state, there is a high possibility that the fragile leads 2 will bend when the adhesive 3 is applied, and this will lower the production yield of the lead frame.

Further, in the conventional example shown in FIG. 3 (b), the adhesive 3 is applied to each of the internal leads 2 one by one. Depending on the amount of the adhesive 3 applied on the insulating tape 1, it leaks aside from the range of the width of the internal lead 2 and is bonded to the adhesive 3 on the adjacent internal lead 2. However, there is a possibility that a problem similar to that shown in FIG.

An object of the present invention is to provide a lead frame for a semiconductor device which solves the above-mentioned problems, and a method of manufacturing the same.

[0010]

In order to achieve the above-mentioned object, a semiconductor device lead frame according to the present invention comprises a semiconductor device in which a plurality of internal leads provided around an island are bonded and fixed to an insulating tape with an adhesive. A lead frame, wherein the adhesive is applied on the insulating tape in a fine-grained manner, and the internal lead is adhered and fixed to the insulating tape by the fine-grained adhesive. .

The fine-grained adhesive is applied to an insulating tape with a size smaller than a size between adjacent internal leads.

Further, the method of manufacturing a lead frame for a semiconductor device according to the present invention is a method of manufacturing a lead frame for a semiconductor device in which a plurality of internal leads provided around an island are adhered and fixed to an insulating tape passing therethrough with an adhesive. A method of applying the adhesive in a fine-grained state on the insulating tape, and after applying the adhesive, adhesively fixing the internal lead on the insulating tape using the fine-grained adhesive. .

Further, the adhesive is applied on the insulating tape in a fine-grained state by using a transfer method.

Further, the adhesive is applied to the entire surface of the insulating tape, and a cut mark is formed on the adhesive applied surface of the insulating tape to make the adhesive fine. The contact
The adhesive is not applied to the internal leads, and the adhesive is applied to the tape.
It is applied only to the cloth surface.

According to the present invention, the adhesive is made into fine particles and applied on the insulating tape, and the internal leads are bonded and fixed on the insulating tape using the fine adhesive.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1A is a plan view showing a lead frame for a semiconductor device according to Embodiment 1 of the present invention, and FIG. 1B is a sectional view taken along line AA 'of FIG. 1A. (C) is a plan view showing the adhesive applied on the insulating tape.

As shown in FIG. 1A, the lead frame for a semiconductor device has an island 6 for mounting a semiconductor element, and the island 6 is supported on the frame 5 by suspension leads 8. Also, around the island 6,
A plurality of internal leads 2 are provided, and external leads 7 are formed integrally with the internal leads 2 on the side away from the island 6. The external leads 7 are connected to each other by tie bars 4, and the tie bars 4 as horizontal rails prevent the resin from flowing out at the time of resin sealing.

The suspension leads 8, internal leads 2, external leads 7, tie bars 4, etc.
However, after resin sealing, molding is performed to individually cut out from the frame 5, cut out the tie bar 4 from between the external leads 7, and electrically separate the adjacent leads 2, 7.

Further, according to the present invention, as shown in FIGS. 1 (b) and 1 (c), the adhesive 3 is formed into fine particles and applied on the insulating tape 1, and the fine adhesive 3 is used. Internal lead 2
Are fixed on the insulating tape 1 to prevent the internal leads 2 from bending.

In the case shown in FIG. 1 (c), the fine-grained adhesive 3 is applied in a circular shape and is regularly arranged.
0 μm) (for example, 80 μm).
m), when the internal leads 2 are bonded onto the insulating tape 1,
Fine-grained adhesives 3 for bonding adjacent internal leads 2 are not bonded to each other.

Next, a method of manufacturing a lead frame for a semiconductor device according to the first embodiment of the present invention will be described. FIG.
In the method for manufacturing a lead frame for a semiconductor device according to the first embodiment of the present invention, a plurality of internal leads 2 provided around an island 6 are adhered and fixed to an insulating tape 1 that crosses these using an adhesive 3. This will be specifically described below.

First, as shown in FIG. 1C, an adhesive 3 is applied on the insulating tape 1 in a fine state using a transfer method by screen printing. The fine-grained adhesive 3 is applied on the insulating tape 1 in a regular array.

Next, as shown in FIGS. 1A and 1B, the surface of the insulating tape 1 coated with the adhesive 3 is turned upward, or the surface coated with the adhesive 3 is turned downward.
Are connected to a plurality of internal leads 2 provided on each side of the island 6.
The inner lead 2 is bonded on the insulating tape 1 by using a fine adhesive 3 with which the inner lead 2 comes in contact with the inner lead 2 by pressing the insulating tape 1 on the inner lead 2 by thermocompression bonding or the like. Fix it.

As described above, according to the first embodiment of the present invention, the adhesive 3 is applied to the insulating tape 1 in advance, and the internal lead 2 is adhered to the insulating tape 1 using the adhesive 3. After the adhesive is applied to the inner leads 2, the inner leads 2 are bonded to the insulating tape 1,
The bending of the internal leads 2 can be greatly reduced.

Further, the adhesive 3 is applied in the form of fine particles, and the diameter of the adhesive 3 is set smaller than the dimension between the adjacent internal leads 2, so that the adhesives 3 for individually adhering the adjacent internal leads 2 to each other. Can be prevented from leaking and joining together, and it is possible to prevent a leak current from being generated between the adjacent internal leads 2 and 2 due to ionic impurities released from the insulating tape 1.

(Embodiment 2) FIG. 2A is a sectional view showing a semiconductor device lead frame according to Embodiment 2 of the present invention, and FIG. 2B is a plan view of the same.

In the first embodiment of the present invention shown in FIG. 1, the adhesive 3 is applied in a fine-grained state by using a transfer method by screen printing. In the second embodiment of the present invention shown in FIG. 3 is applied to the entire surface of the insulating tape 1 and then the cutting marks 9 are mechanically applied to the applied surface using, for example, a dicing device.
Is formed to make the adhesive 3 on the insulating tape 1 into a fine-grained state.

In the first embodiment of the present invention, it is necessary to use a mask when performing the transfer. However, according to the second embodiment of the present invention, by mechanically engraving the cutting trace 9,
Since the adhesive 3 on the insulating tape 1 is in a fine-grain state, there is no need to use a mask or the like, which has an advantage that the manufacturing process can be simplified.

In the first embodiment, the adhesive 3 is formed in a circular shape, and in the embodiment 1, the adhesive 3 is formed in a diamond shape by forming a diamond shape. It is not limited to one.

In the first embodiment, the transfer method by screen printing is used. However, the transfer method is not limited to screen printing, and the adhesive 3 can be applied on the insulating tape 1 in a fine grain state. Any transfer method may be used as long as it is a transfer method.

[0032]

As described above, according to the present invention, the adhesive is applied to the insulating tape in the form of fine particles, and after the application, the internal leads are bonded to the insulating tape using the fine-grain adhesive. Since the fixing is performed, the occurrence rate of bending of the internal leads can be suppressed lower than in the case where the adhesive is directly applied to the internal leads.

Furthermore, by making the application size of the adhesive smaller than the size between the adjacent internal leads, it is possible to prevent the adhesives that individually bond the adjacent internal leads from leaking out and joining. .

[Brief description of the drawings]

FIG. 1A is a plan view showing a lead frame for a semiconductor device according to a first embodiment of the present invention, and FIG.
FIG. 4C is a cross-sectional view taken along line A ′, and FIG. 4C is a plan view illustrating the adhesive applied on the insulating tape in the first embodiment of the present invention.

FIG. 2A is a cross-sectional view showing a lead frame for a semiconductor device according to a second embodiment of the present invention, and FIG. 2B shows an adhesive applied on an insulating tape in the second embodiment of the present invention. It is a top view.

FIG. 3A is a cross-sectional view showing a semiconductor device lead frame according to a conventional example, and FIG. 3B is a cross-sectional view showing another conventional semiconductor device lead frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation tape 2 Internal lead 3 Adhesive 9 Cutting trace

Claims (6)

(57) [Claims] 1. A lead frame for a semiconductor device, wherein a plurality of internal leads provided around an island are bonded and fixed to an insulating tape with an adhesive, wherein the adhesive is applied on the insulating tape in the form of fine particles. A lead frame for a semiconductor device, wherein the internal lead is adhered and fixed to the insulating tape with the fine-grained adhesive. 2. The lead frame for a semiconductor device according to claim 1, wherein the fine-grained adhesive is applied to an insulating tape with a size smaller than a size between adjacent internal leads. . 3. A method for manufacturing a lead frame for a semiconductor device, wherein a plurality of internal leads provided around an island are bonded and fixed to an insulating tape passing therethrough with an adhesive, wherein the adhesive is in a fine-grained state. A method of manufacturing a lead frame for a semiconductor device, comprising: applying the internal leads onto the insulating tape using the fine-granular adhesive after the application onto the insulating tape. 4. The method for manufacturing a lead frame for a semiconductor device according to claim 3, wherein the adhesive is applied in a fine-grained state on the insulating tape by using a transfer method. 5. The method according to claim 3, wherein the adhesive is applied to the entire surface of the insulating tape, and a cut mark is formed on the adhesive applied surface of the insulating tape to make the adhesive fine. 5. The method for manufacturing a lead frame for a semiconductor device according to claim 1. 6. The method according to claim 1, wherein the adhesive is not applied to the internal leads.
The feature is that it is applied only to the adhesive applied surface of the tape.
6. A lead frame for a semiconductor device according to claim 3, wherein
Manufacturing method.