JPS5823946B2 - semiconductor equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device having a conductive plate between a semiconductor substrate and an external electrode that requires positioning with respect to the external electrode.

FIG. 1 is a longitudinal cross-sectional view of a conventional flat silicon risk having a conductive plate between a semiconductor substrate and an external electrode.

In FIG. 1, 1 is an external anode electrode, 2 is a semiconductor substrate,
3 is a conductive plate made of molybdenum or the like and disposed between the semiconductor substrate 2 and an external cathode electrode to be described later; 4 is an external cathode electrode;
5 is a coil spring, 6 is a gate lead supporter, 7 is a gate lead, and 8 is a gate sleeve made of an insulator.

In this case, the positioning of the external cathode electrode 4 and the conductive plate 3 is as follows:
This is done by a gate lead support 6 supported from the bottom of the recess of the external cathode electrode 4 by a coil spring 5.
Since the thickness of the conductive plate 3 is insufficient compared to the vertical movable distance of the conductive plate 3, the conductive plate 3 does not touch the top surface of the external cathode electrode 4 (A shown in FIG. 1). It crosses over a slight gap between the top surface of the gate lead support 6 (B shown in FIG. 1), enters between the gate lead support 6 and the semiconductor substrate 2, and connects the gate lead 7 and the semiconductor substrate. The phenomenon of incomplete contact with 2 sometimes occurred.

SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor device in which the above-mentioned drawbacks are eliminated by providing an engaging body for restricting the movement of a conductive plate in a recessed portion of an external cathode electrode.

The present invention will be explained below based on the drawings.

FIG. 2 is a longitudinal cross-sectional view of an embodiment in which the present invention is applied to a flat silisk.

In FIG. 2, 9 is a conductive plate having an opening whose dimensions on the semiconductor substrate 2 side are larger than those on the external cathode electrode 4 side, and 10 is an engaging portion that engages with the opening in the conductive plate 9. It is a tip-shaped body having a flange-like part and serving as an engaging body that is inserted into the recessed part of the external cathode electrode 4 and restricts the movement of the conductive plate 9.

FIGS. 3 and 4 are perspective views showing examples of openings in the conductive plate 10, and FIG. 5 is a perspective view of the pot-like body 10 in which the engaging portion is shaped like a brim.

An outline of the method for assembling the flat-shaped silisk according to the embodiment is as follows.

First, the tip 10 is placed on the conductive plate 9, and then the coil spring 5 is placed inside the tip 10.

Next, pass the gate lead 7 through the gate lead support 6,
Furthermore, the gate sleeve 8 is covered and these are placed inside the cup-like body 10.

Thereafter, the pot 10 is placed in the recess of the external cathode electrode 4, the semiconductor substrate 2 is placed, and the external anode electrode 4 is attached.

The flat silice manufactured in this manner is the sum of the distance from the bottom surface C of the external anode electrode 1 to the top surface A of the external cathode electrode 4 shown in FIG. 2, and the thickness of the semiconductor substrate 2 and the conductive plate 9. [hereinafter referred to as the effective vertical movement distance of the conductive plate 9], the height of the pot-shaped body 10 can be made sufficiently large.

In order to shift the conductive plate 9 with respect to the external cathode electrode 4 in the vertical direction in FIG. By making the height of the shaped body 10 sufficiently larger than the effective vertical movement distance of the conductive plate 3, it becomes impossible for the conductive plate 9 to shift laterally.

Further, according to the present invention, since the coil spring 5 that presses the gate lead 7 against the semiconductor substrate 2 is supported at the bottom of the cup-like body 10, the depth of the recess of the external cathode electrode 4 is
It only needs to be larger than the height of the tip-shaped body 10, and there is no problem even if the machining accuracy is lower than that of the conventional one.

FIG. 6 is a perspective view showing another shape of the engaging body.

The engaging body shown in FIG. 6 is the cup-shaped body shown in FIG.

Unlike , it is a cylindrical body with a flange at one end, which can prevent the conductive plate from shifting in the same way as a cup-shaped body.

In this case, the coil spring that presses the gate lead is supported at the bottom of the recess of the external cathode electrode.

The present invention can be applied not only to the above-mentioned flat type diodes, but also to parallel and stud-type diodes and all types of cyrisks.

In the case of a diode, conventionally a coil spring, a gate IJ-board support body, etc., as shown in FIG. Instead, only the engaging body that engages with the conductive plate is required, and the components can be simplified, making it inexpensive and simple in structure.

Further, the present invention can also be applied to a semiconductor device in which a brazing method is used instead of a pressurizing method for the connection between a gate lead and a semiconductor substrate.

As described in detail above, in the semiconductor device according to the present invention, the external electrode has a groove formed in the concave portion facing the main surface of the semiconductor substrate, and a tip portion facing the semiconductor substrate that protrudes in a direction perpendicular to the axis. an engaging body having a stop portion; and a conductive plate disposed between the semiconductor substrate and the external electrode, the conductive plate having an opening portion having a side wall held between the stop portion and the external electrode. This has the effect of preventing misalignment of the conductive plate.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a conventional flat-shaped cylisk, FIG. 2 is a longitudinal sectional view of a flat-shaped cylisk that is an embodiment of the present invention, and FIGS. 3 and 4 each show an example of an opening in a conductive plate. The perspective view, FIG. 5, and FIG. 6 are perspective views each showing an example of an engaging body. In the figure, 1 is an external anode electrode, 2 is a semiconductor substrate, 3 and 9 are conductive plates, 4 is an external cathode electrode, and 10 is an engaging body. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A semiconductor substrate having at least one PN junction, an external electrode facing the entire surface of the semiconductor substrate and having a concave portion on the surface facing the semiconductor substrate, an external electrode placed in the concave portion and having a tip portion facing the semiconductor substrate. an engaging body having a locking portion protruding in a direction perpendicular to the axis; and a lock disposed between the semiconductor substrate and the external electrode and held between the external electrode and the locking portion of the engaging body. A semiconductor device including a conductive plate having a joint.