JPH0464255A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the crawl-up of gel and join sealing resin with a case normally by providing a craw-up preventive part for preventing the crawl-up of gel-form filler on the inner sidewall of a case. CONSTITUTION:By providing a projection 1a at the inner sidewall of a case 1, gel-form filler 6 can be prevented from crawling up the inside of a case close to the topside, and the sealing resin 7 injected thereafter is joined normally with the case 1. Projections 1a in various shapes and recesses 1e in various shapes are conceivable for the shapes of the crawl-up preventive parts. By providing the crawl-up preventive parts in proper shapes on the inner sidewall of the case 1, the crawl-up of gel-form filler 6 can be prevented by the projections 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device, and particularly to the exterior of a power module.

[Prior Art 1] FIG. 4 is a sectional view showing the configuration of a conventional power module. In FIG. 4, reference numeral 1 denotes a bottomless case made of side walls made of synthetic resin, and a metal heat dissipation plate 2 is bonded as the bottom plate of this case 1. An insulating substrate (or insulating film) 3 is adhered onto this heat sink 2, and conductor wiring is further formed on the insulating substrate (or insulating film) 3. A semiconductor element 4 is placed on the insulating substrate 3.
is mounted, and the lower end portion 5a of the lead 5 is attached to the pad of the conductor wiring portion on the insulating substrate 3 connected to the semiconductor element 4.
are connected via a solder layer. Further, a gel-like filling 6 is injected into the case 1, and a sealing resin 7 is further injected thereon to seal it.

[Problem to be Solved by the Invention 1] By the way, the above-mentioned gel-like filler 6
Because it has the property of crawling up the inner wall of the
If the case height 1 is low as shown in a), the gel-like filling 6 will crawl up the inner wall of the case 1 and up to the top surface of the case 1, causing the sealing resin 7 to be injected and filled afterwards. Therefore, a problem has arisen in that the semiconductor element 4 cannot be sealed tightly.

In addition, in order for the sealing resin 7 to properly bond to the case 1, the height of the case 1 needs to be made higher than the crawling part of the gel-like filling 6, as shown in FIG. 5(b). Therefore, the external height of the semiconductor device inevitably increases, resulting in a problem that the overall device becomes larger.

[Means for Solving the Problems 1] A semiconductor device according to the present invention is provided with a creep-up prevention portion on the inner side wall portion of the case to prevent the gel-like filling from creeping up.

[Function 1] In this invention, a creep-up prevention part is provided on the inner side wall of the case to prevent the gel-like filling from creeping up, so that the gel-like filling does not creep up and the subsequent sealing resin is not applied. There is no problem with injection filling.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a semiconductor device showing an embodiment of the present invention.

In FIG. 1, the same reference numerals as in FIG. 4 indicate the same constituent parts, so the explanation thereof will be omitted. Reference numeral 1a denotes a crawling prevention portion provided on the inner side wall of the case 1, and is made of, for example, a rectangular protrusion.

As described above, by providing the protrusion 1a on the inner side wall of the case 1, the gel-like filler 6 is prevented from crawling up the inner side of the case 1 to near the top surface, and the sealing resin 7 is injected and filled afterwards. is successfully joined to case 1.

Note that the protrusions 1a may be provided on any part of the inner side wall of the case 1, and the number thereof is not limited.

In addition, the shape of the crawling prevention part is shown in Fig. 2 (a) to (f).
As shown in , various shapes of protrusions 18 to 1d or various shapes of recesses 1e, 1f, etc. can be considered.

By providing a crawling-preventing portion of an appropriate shape on the inner side wall of the case 1 in this way, it is possible to prevent the gel-like filling 6 from climbing up with the protrusion 1a, as shown in FIG. 3(a). Also, as shown in FIG. 3(b), when the case 1 is slightly tilted, or as shown in FIG. 3(C), if the amount of gel-like filling 6 is large, the surface Due to the action of tension, the protrusion 1a has the effect of damming up the gel-like filling 6. The other protrusions 1b to 1d and the recesses 1e and if have the same effect.

[Effects of the Invention] As explained above, in the present invention, a crawling prevention part for preventing the gel filling from creeping up is provided on the inner side wall of the case, so that the gel can be prevented from climbing up. ,
The sealing resin can be properly bonded to the case. Moreover, this has the effect of providing good workability and a thin semiconductor device.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the configuration of a semiconductor device showing one embodiment of the present invention, FIGS. 2(a) to (f) are cross-sectional views showing other examples of shapes of the crawling prevention portion of the present invention, and FIG. FIG. 4 is a cross-sectional diagram explaining the details of the present invention, FIG. 4 is a cross-sectional diagram of a conventional semiconductor device, and FIG. 5 is a schematic cross-sectional diagram explaining how the gel-like filling material crawls up. In the figure, 1 is a case, 1a to 1d are protrusions, Ie, 1
f is a recessed portion, 2 is a heat sink, 3 is an insulating substrate, 4 is a semiconductor element, 5 is a lead, 6 is a gel-like filling, and 7 is a sealing resin. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa (2 others) Figures (a) (b) (d) (e) le, 1f Part 4 (C) (f) Figures 1, :I

Claims (1)

[Claims] A bottomless case, a heat sink attached to the bottom of the case to form a bottom plate of the case, an insulating substrate bonded to the heat sink, and a conductor wired on the insulating substrate. A semiconductor comprising a mounted semiconductor element and a lead, a gel-like filling injected into the case so that the surface thereof is located above the semiconductor element, and a sealing resin injected and filled after that. 1. A semiconductor device, characterized in that a creep-up prevention portion for preventing the gel-like filling from creeping up is provided on an inner side wall portion of the case.