JPH0669397A - Lead frame for semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] In a semiconductor device after resin encapsulation, the post-process tie bar cutting process, the resin removal of the external leads and the solder plating process are eliminated, and the deformation of the external leads after the external leads are molded is prevented. . [Structure] At least a part between external leads 5 is filled with solder 6, and each external lead 5 is connected with solder 6 to prevent resin leakage at the time of resin sealing and to heat solder 6 by heating. Since melt cutting is possible, the tie bar cutting step and the step of removing the resin adhered to the external leads 5 are not required, and productivity and quality can be improved. further,
By heating the solder 6 after the external lead 5 molding step, the solder 6 serves as a reinforcement for the external lead 5 during molding,
The flatness of the tips of the external leads 5 can be improved, and the productivity and quality can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device lead frame, and more particularly to a semiconductor device lead frame used in a resin-sealed semiconductor device.

[0002]

10 is a plan view of an example of a conventional semiconductor device lead frame, FIG. 11 is a plan view after resin sealing using the semiconductor device lead frame of FIG. 10, and FIG. 12 is a cross section of FIG. 13 is a partially enlarged plan view of the external lead of FIG. 11, and FIG. 14 is a plan view of the external lead of FIG. 13 after cutting the tie bar.

Conventionally, as shown in FIGS. 10 to 12, this type of semiconductor device lead frame is made of the same material, and the external leads 5 are connected to each other by tie bars 12.

The semiconductor device after resin encapsulation is completed in the subsequent steps, as shown in FIGS. 13 and 14, after the tie bar 12 is cut, and subsequently, the external lead 5 is subjected to a solder plating step and a molding step. Was there.

At this time, since the adhered resin 11 partially adheres to the outer leads 5 in the tie bar cutting step, it is necessary to add a step of removing the adhered resin 11 before the subsequent solder plating step.

[0006]

Since the above-mentioned conventional lead frame has a structure in which the tie bar 12 is provided between the external leads 5, the tie bar 12 is cut in a step after the mold sealing, and each external lead 5 is cut. Since it is necessary to cut the electrical conductivity between the leads 5, there is a problem that the quality and productivity are reduced.

Further, since the resin at the time of mold sealing adheres to the side surface and the surface of the external lead 5, it is necessary to remove the adhered resin 11 and a step of removing the resin 11 is required, and the productivity is lowered. was there.

Further, since the strength of the outer lead 5 is lowered by forming the outer lead 5 after cutting the tie bar 12, the outer lead 5 is formed when the outer lead 5 is formed.
However, there is a problem that it is easily deformed and induces deformation failure.

In addition, in the conventional technique, there is a problem that a plating step is required to perform solder plating on the external leads 5 and productivity is reduced.

An object of the present invention is to provide a lead frame for a semiconductor device which can obtain a semiconductor device of high quality and high productivity without deformation defects of external leads.

[0011]

According to the present invention, there is provided a resin-encapsulated semiconductor having an island on which a semiconductor element is mounted, internal leads arranged around the island, and external leads connected to the internal lead. In a device lead frame, solder is embedded in at least a part between the external leads, and the external leads are connected by the solder.

[0012]

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

FIG. 1 is a plan view of a first embodiment of the present invention, FIG. 2 is a plan view after resin sealing using the first embodiment of FIG.
3 is a sectional view of FIG. 2, FIG. 4 is a partially enlarged plan view of the external lead of FIG. 2, and FIG. 5 is a plan view of the external lead of FIG.

In the first embodiment, as shown in FIGS. 1 to 5, the external lead 5 is a portion for electrically conducting outside the resin encapsulation portion 8 of the semiconductor device. Solder 6 is embedded in a part of each of the external leads 5
The spaces are connected by solder 6. The solder 6 connected between the external leads 5 blocks the resin leaking from the resin sealing portion 8 when the solder 6 between the external leads 5 is resin-sealed.
It is possible to play the role of the tie bar 12 in the conventional semiconductor device shown in FIG. Further, the solder 6 can be melted and cut by receiving heat as shown in FIG.

FIG. 6 is a plan view of a second embodiment of the present invention, FIG. 7 is a sectional view after resin sealing using the second embodiment of FIG. 6,
8 is a partially enlarged plan view of the external lead shown in FIG. 6, and FIG. 9 is shown in FIG.
FIG. 6 is a plan view after melting and cutting the solder of FIG.

In the second embodiment, as shown in FIGS. 6 to 9, the solder 6 is embedded in the entire space between the external leads 5, and the solder 6 embedded between the external leads 5 is a resin for resin encapsulation. It is possible to prevent leakage. In addition, the solder 6 can be melted and cut by receiving heat as shown in FIG. 9, and at the same time, the external lead 5 can be coated with the solder 6.

Further, the above-mentioned solder 6 is the external lead 5
It is possible to reinforce the external leads 5 in the molding step, and by melting and cutting the solder 6 after molding, the respective external leads 5 after molding can be separated.

[0018]

As described above, according to the present invention, in the resin-encapsulated lead frame for a semiconductor device, solder is embedded in at least a part between the external leads to connect the respective external leads. It is possible to prevent resin leakage during resin sealing performed by the tie bar of the lead frame. Since this solder can be melted and cut by receiving heat, the step of cutting the tie bar after resin sealing and the step of removing the adhered resin generated at the time of cutting the tie bar are unnecessary, and there is an effect that productivity and quality can be improved.

The step of applying heat has the flexibility that it can be installed in any step after resin molding and after external lead molding.

[Brief description of drawings]

FIG. 1 is a plan view of a first embodiment of the present invention.

FIG. 2 is a plan view after resin sealing using the first embodiment of FIG.

3 is a cross-sectional view of FIG.

4 is a partially enlarged plan view of the external lead shown in FIG.

5 is a plan view of the external lead after the melting and cutting of the solder in FIG. 4;

FIG. 6 is a plan view of the second embodiment of the present invention.

7 is a cross-sectional view after resin sealing using the second embodiment of FIG.

8 is a partially enlarged plan view of the external lead of FIG.

FIG. 9 is a plan view after melting and cutting the solder of FIG. 8;

FIG. 10 is a plan view of an example of a conventional semiconductor device lead frame.

11 is a plan view after resin sealing using the lead frame for a semiconductor device of FIG.

12 is a cross-sectional view of FIG.

FIG. 13 is a partially enlarged plan view of the external lead shown in FIG.

14 is a plan view of the external lead after cutting the tie bar of FIG.

[Explanation of symbols]

 1 lead frame 2 frame lead frame 3 island 4 internal lead 5 external lead 6 solder 7 semiconductor element 8 resin sealing part 9 gold wire 10 dam part 11 adhered resin 12 tie bar

Claims (1)

[Claims] 1. A resin-encapsulated lead frame for a semiconductor device, comprising: an island on which a semiconductor element is mounted; internal leads arranged around the island; and external leads connected to the internal leads. A lead frame for a semiconductor device, characterized in that solder is embedded in at least a part between the leads to connect the respective external leads with the solder.