JPH0155577B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a semiconductor device, and particularly to a package for a high-power semiconductor device.

[Prior Art] Conventionally, there has been a semiconductor device of this type as shown in FIG. In FIG. 1, 1 is a ceramic seal, 2 is a cathode flange, and 3 is a guide ring for fixing a semiconductor element in a package, which are mainly made of silicone rubber, Viton rubber, ceramic, or the like. 4 is an insulating rubber for passivation of the semiconductor element; 5 is a semiconductor element such as a thyristor or transistor; 6 is a gate aluminum electrode which is an auxiliary electrode for controlling the main current of the semiconductor element 5;
7 is an aluminum wire, 8 is a bonding part where the aluminum wire 7 is bonded with an ultrasonic bonder, 9 is a cathode electrode such as a molybdenum plate, 10 is an insulating tube for taking out the aluminum wire 7 to the outside, and 11 is a gate pipe. be.

In the conventional assembly, after the guide ring 3 is attached to the ceramic seal 1, the semiconductor element 5 is further inserted. Thereafter, an aluminum wire 7 is bonded onto the gate aluminum electrode 6 of the semiconductor element 5 using an ultrasonic bonder. This aluminum wire 7 extends around the outer circumference of the semiconductor element 5 at equal intervals (2 to 3
mm), the end is passed through the insulating tube 10 and led to the gate pipe 11, and the tip of the gate pipe 11 is welded by arc welding.

FIG. 2 is an external side view of the semiconductor element 5 assembled as described above. In this figure, 12 represents a copper block and 13 represents an electrode copper block.

Since the conventional semiconductor device is configured as described above, it has the following drawbacks.

There was a risk that the insertion end of the insulating tube 10 and the aluminum wire 7 would be cut if a load such as tension was applied from the outside during the temporary assembly process. This aluminum wire 7 has a diameter of about 0.3 to 0.5 mm and is annealed, so it is extremely weak against tension. If the aluminum wire 7 breaks, the gate and cathode will become open, which will damage the semiconductor device. 5 becomes unusable.

When this aluminum wire 7 is arc welded at the tip of the gate pipe 11, the melting point is as high as 660° C., so welding requires great skill and skill.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional products as described above and to obtain products with higher reliability in terms of characteristics.By improving the ability to bond aluminum wire to the guide ring, high power The purpose is to provide a semiconductor device suitable for various applications.

[Embodiments of the invention]

FIG. 3, FIG. 4, and FIG. 5 are diagrams showing an embodiment of the present invention. In these figures, 14 is a silver brazing material, 15 is an insulating plate such as ceramic,
In part B, 16 is a spring, and 17 is a spacer for fixing the spring 16 and adhering the silver lead wire 18.

Incidentally, portions A and B in FIG. 5 are shown together in this figure at the same time, but in actual use, one of them is used.

The feature of this invention is that the aluminum wire 7 is bonded to the guide ring 3. The guide ring 3 is made of an insulator such as ceramic, and a silver brazing material 14 is soldered onto the guide ring 3. The thickness of this brazing material 14 is approximately 500 μm.

Bonding of aluminum wire 7 is shown in Figures 3 and 4.
As shown in the figure, the gate aluminum electrode 6 on the semiconductor element 5 side and the silver solder material 14 of the guide ring 3 are alternately wired by bonding. This makes the semiconductor element 5 more securely fixed than in the prior art.

Furthermore, since the electrodes are directly taken out to the outside through the gate pipe 11 as shown in FIGS. 3 and 5, the insulating tube 10 as in the conventional case is not required. Furthermore, 14 parts of silver brazing material and 1 gate pipe
By using the silver lead wire 18 as the wiring connecting the gate pipes 1 to 1, arc welding of the tip of the gate pipe 11 becomes much easier than in the past. Also,
Since the insulating tube 10 is no longer necessary, there is no longer any possibility of disconnection of the aluminum wire 7, which was a concern in the past.

Furthermore, as in the embodiment shown in FIG. 5, a structure like section A or a press-contact structure like section B has become possible.

The structure of part A is such that a silver lead wire 18 is bonded to a silver brazing material 14 using a Cerasolzer or an ultrasonic bonding method, and is taken out to a gate pipe 11.
This silver lead wire 18 is the aluminum wire 7 with a diameter of φ0.3~
Compared to 0.5, the diameter can be increased to about φ1.4 to 1.7. Therefore, it is particularly effective in reducing current density and impedance in GTO thyristors, etc., where the gate current flows around 200A to 300A.

The structure of part B is further implemented for the purpose of taking out the gate lead wire to the outside by using a press-contact structure. This method is particularly advantageous for the above-mentioned GTO thyristor, etc., since it is possible to change from point contact to surface contact like bonding.

The material of the insulating plate 15 is preferably ceramic. Also, a ring shape is simpler and more reliable. The material of the guide ring 3 is preferably ceramic. In addition, as in this embodiment, after bonding the semiconductor elements 5, the RTV is placed on the aluminum wires 7 alternately wired.
Insulating with rubber such as rubber is particularly effective in fixing the semiconductor element 5 and insulating between the gate and cathode.

Furthermore, from the side of the semiconductor element 5, the area of the electrode having the same potential as the aluminum electrode increases by the amount of the silver brazing material 14, so that the density of the current concentrated on the gate aluminum electrode 6 can be reduced. As described above, the present invention provides a flat thyristor having a pressure contact structure, particularly a flat thyristor having a pressure contact structure.
Effectively works on GTO thyristors and flat transistors.

In the above embodiments, a press-fitted flat type thyristor has been described, but the same effects as in the above embodiments can be obtained even if the present invention is applied to a press-fitted flat type transistor. Further, the guide ring 3 may be used to position the semiconductor element 5 and the external container of the semiconductor device.

〔Effect of the invention〕

As explained above, the present invention supports the outer periphery of a semiconductor element by an insulating guide ring,
Since the auxiliary electrode of the semiconductor element is taken out to the outside by relaying the conductive annular part provided on a part of the guide ring, the guide ring acts as a positioner, simplifying the configuration and making assembly easier. You can reduce troubles. Furthermore, since it can be relayed by a conductive annular portion, there is an advantage that a larger current can flow than in the past.

[Brief explanation of drawings]

Figure 1 is a plan view showing a conventional semiconductor device, Figure 2 is a plan view showing a conventional semiconductor device;
The figure is a side view of a thyristor with pressure-welded flat structure, the third
Figures 4 and 5 are a plan view, a sectional view, and an enlarged sectional view showing an example of the structure of essential parts of an embodiment of the present invention. In the figure, 1 is a ceramic seal, 2 is a cathode flange, 3 is a guide ring, 4 is insulating rubber, 5 is a semiconductor element, 6 is a gate aluminum electrode, 7 is an aluminum wire,
8 is a bonding part, 9 is a cathode electrode, 11 is a gate pipe, 12 is a copper block, 13 is an electrode copper block, 14 is a silver brazing material, 15 is an insulating plate, 16
is a spring, 17 is a spacer, and 18 is a silver lead wire. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A semiconductor element having at least two electrodes for flowing a main current and an auxiliary electrode for controlling the main current, and a guide ring made of an insulator that supports the outer periphery of the semiconductor element. The semiconductor device is characterized in that a part of the guide ring has a conductive annular portion, and the auxiliary electrode of the semiconductor element is taken out to the outside by relaying the annular portion. 2. The semiconductor device according to claim 1, wherein the auxiliary electrode of the semiconductor element and the conductive annular portion provided on the guide ring are electrically connected by wire bonding. 3. The semiconductor device according to claim 1, wherein the conductive annular portion provided on the guide ring and the external electrode are electrically connected by a lead wire. 4. The semiconductor according to claim 1, wherein the conductive annular portion provided on the guide ring and the external electrode are electrically contacted by pressing a lead wire. Device.