JPH039538A - Resin seal metal mold for semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the inclination of a semiconductor element mounting part caused by resin pressure at the time of sealing, by installing protruding parts for pressing a semiconductor element mounting part on the main mold surface of the cavity part of a metal mold. CONSTITUTION:A lead frame 10 is sandwiched by a top force 1 and a bottom force 2; resin is sealed into a cavity part 3 formed by the top force 1 and the bottom force 2; thereby resin sealing is performed. In this metal mold, protruding parts 6 for pressing a semiconductor element mounting part 9 are installed on the main mold surface of the top force 1 and the bottom force 2 constituting the cavity part 3. That is, the protruding parts 6 installed on the top force 1 and the bottom force 2 press the semiconductor element mounting part 9 and a printed board 11 arranged thereon from vertical direction, and arranged them at a position where contact with metal thin wires can be evaded. Thereby the inclination of the semiconductor element mounting part 9 caused by resin pressure can be prevented.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a resin sealing mold for semiconductor devices.

[Conventional technology]

Conventionally, this type of resin-sealing mold consists of an upper mold 1 and a lower mold 2, as shown in the longitudinal cross-sectional view of FIG. This mold has a hollow part (hereinafter referred to as cavity part 3) for sealing a semiconductor element 7 placed between two upper and lower molds as a resin molded IC of a predetermined shape, and a resin passage. It is composed of a runner part 4 and a gate part 5 which serves as an injection port from the runner part 4 to each cavity part 3.

[Problem to be solved by the invention]

The above-described conventional resin-sealing mold for a semiconductor device has the disadvantage that the semiconductor element mounting portion tilts due to the pressure of the resin because the encapsulating resin is filled from one direction laterally in the cavity portion.

If this inclination is severe, the longitudinal cross-sectional view of FIG.

As shown in FIG. 2, the thin metal wire 8 that electrically connects the lead lθ and the semiconductor element 7 may be cut, or the thin metal wire 8 may be exposed from the resin 13 that is the package surface.

In recent years, the degree of integration of semiconductor devices such as microcomputers and gate arrays has rapidly increased, and the area of semiconductor devices has also rapidly increased. Along with this, the number of packaging bottles is also rapidly increasing.

This ultra-bin resin mold package is designed to have a large semiconductor element mounting portion, a narrow pitch between external leads, and a narrow internal lead width and short length.

In order to increase the number of bins, the processing precision of the lead frame would be exceeded, so as shown in the vertical cross-sectional view of FIG. Installed semiconductor devices have also been devised.

In such a super multi-bin package, since the semiconductor element mounting part is larger than the conventional one, the semiconductor element mounting part is inclined even with a small resin pressure, and the above-mentioned drawback is likely to occur.

[Means to solve the problem]

The present invention provides a resin sealing mold for a semiconductor device in which a lead frame is sandwiched between the upper and lower molds, and a resin is sealed in a hollow part formed by the upper and lower molds to perform resin sealing. This is a resin-sealed mold for a semiconductor device in which a protrusion for pressing a semiconductor element mounting portion is provided on each main mold surface of the mold.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the present invention. FIG. 2 is a longitudinal cross-sectional view of the above-mentioned embodiment when a lead frame on which a semiconductor element is mounted is sandwiched, and FIG. 3 is a plan view of the lower mold. FIGS. 4(a) and 4(b) are plan views of an upper mold and a lower mold in which the positions of the projections of the above embodiment are different.

In FIG. 1, the cavity part 3 of the upper mold 1 and the lower mold 2
A conical protrusion 6 is provided on each main mold surface. In this example, the projections 6 are arranged at the same position in both the upper and lower molds, but as shown in FIGS. 4(a) and 4(b), they do not oval even if the projections 6 are located at different positions in the upper and lower molds.

In FIG. 2, protrusions 6 on the upper mold 1 and the lower mold 2
1 holds down the semiconductor element mounting portion 9 and the printed circuit board 1 installed thereon from above and below. This protrusion 6 is arranged at a position where it does not come into contact with the thin metal wire 8.

5 and 6 are longitudinal sectional views of the second embodiment of the present invention, with FIG. 5 showing the state before resin is encapsulated, and FIG.
The figure shows the state immediately after being sealed.

This embodiment has a structure in which the protrusion 6 can move up and down. When this mold is used to release the cured mold resin, the protrusions 6 present on the upper mold 1 and the lower mold 2 retract to below the surface of the main mold, as shown in FIG.

Since the protrusion retracts below the main mold surface of the cavity portion in this manner, there is an advantage that the sealed semiconductor device can be easily removed from the mold compared to the first embodiment.

〔Effect of the invention〕

As explained above, the present invention has the effect that the semiconductor element mounting part does not tilt due to the resin pressure during encapsulation by having the protrusion that presses the semiconductor element mounting part on the main mold surface of the cavity part of the mold. .

The second advantage is that the semiconductor element mounting part does not tilt.
Since the semiconductor element and the semiconductor element mounting part do not need to be placed at the center of the package height and can be placed above or below the center, there is an effect that the degree of freedom in designing and assembling the semiconductor device is improved.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the first embodiment of the present invention, Fig. 2 is a longitudinal sectional view thereof, Fig. 3 is a plan view of the lower mold, and Fig. 4 (
a) and (b) are respectively plan views of the upper and lower molds, FIGS. 5 and 6 are longitudinal sectional views showing the second embodiment of the present invention, and FIGS. 7 and 8, respectively. and FIG. 9 are vertical cross-sectional views showing conventional resin-sealing molds for semiconductor devices. DESCRIPTION OF SYMBOLS 1... Upper mold, 2... Lower mold, 3... Cavity part, 4... Part of runner, 5... Gate part, 6...
Projection, 7... Semiconductor element, 8... Metal thin wire, 9...
...Semiconductor element mounting section, 10...Lead, 11...
Printed circuit board, 12... copper wiring, 13... resin.

Claims (1)

[Claims] In a resin sealing mold for a semiconductor device in which a lead frame is sandwiched between the upper and lower molds and a resin is sealed in a hollow part formed by the upper and lower molds to perform resin sealing, each of the upper and lower molds forming the hollow part. 1. A resin-sealing mold for a semiconductor device, characterized in that a protrusion for pressing a semiconductor element mounting portion is provided on the main mold surface.