JPH0142347Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a resin-sealed semiconductor device, and particularly to a connection structure for internal leads connected to control electrodes of a semiconductor pellet.

[Technical background of the invention and its problems]

There is a resin-sealed semiconductor device as shown in FIG. 1 that houses a semiconductor pellet having a control electrode such as a thyristor.

That is, in the semiconductor device having this structure, a semiconductor pellet 3 is connected to a substrate 1 via a temperature compensation plate 2, a cathode electrode 4 and a gate electrode 5 are formed on one main surface of the pellet 3, and these electrodes 4, A cathode external terminal 6 and a gate internal lead 7 are connected to the terminals 5 and 5, respectively.

Each of the above-mentioned components is housed in a case or the like (not shown), and filled with sealing resin to form the resin sealing section 8 .

Depending on the current capacity of the semiconductor pellet 3, the internal lead 7 may be a relatively thick solid wire or a bent plate.

These gate internal leads 7 are soldered to the gate electrodes.

However, the above structure has the following drawbacks. That is, since a relatively thick single wire or plate material is used for the internal gate lead 7, flexibility or flexibility is poor, and the mechanical stability of the resin sealing portion 8 is poor.
The problem is that the internal gate lead 7 may peel off from the gate electrode 5 due to thermal stress.

[Purpose of invention]

The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to provide a semiconductor device that can effectively prevent peeling of internal gate leads drawn out from gate electrodes.

[Summary of the idea]

The present invention uses a stranded wire made by twisting thin wires as an internal lead for a gate instead of using a relatively thick single wire or plate material as in the past, so that the internal lead maintains flexibility or flexibility, and the internal lead The gate electrode is not directly connected to the gate electrode, but is connected via a relay terminal with a large surface area of the connection part, thereby preventing an accident in which the internal lead for the gate separates from the gate electrode.

[Example of idea]

3 and 4 are a partially cutaway joint view showing a first embodiment of the present invention and a perspective view of a relay terminal used in the above embodiment.

In these figures, the substrate 11 as a heat sink
A temperature compensating plate 12 is placed thereon, and a semiconductor pellet 13 having a cathode electrode 14 and a gate electrode 15 on one main surface thereof is fixed onto the temperature compensating plate 12. Cathode electrode 1 of this pellet 13
4 is connected to a cathode terminal 16 having a through hole 16a in its center.

A gate internal lead 17 is connected to the gate electrode 15, and this internal lead 17 is made of a twisted wire made by twisting a large number of thin wires together. Therefore, this internal lead 17 has flexibility.

Further, one end of the internal lead 17 is not directly connected to the gate electrode 15 and is connected to the relay terminal 19.
connected via. As is clear from the enlarged perspective view of FIG. 4, this relay terminal 19 has a bottomed hole 20 in its center, and one end of the internal lead 17 is inserted into the bottomed hole 20 and then soldered using solder or the like. It is something that is fixed.

Further, the connection between the relay terminal 19 and the gate electrode 15 is also made using solder or the like. Note that the outer diameter of the relay terminal is determined to be a predetermined size based on the surface area of the gate electrode 15;
It is larger than the outer diameter of 7.

Each of the above components is housed in a case or the like (not shown), and the case or the like is filled with a sealing resin to form the resin sealing portion 18.

In the semiconductor device obtained as described above, the gate internal lead 17 embedded in the resin sealing part 18 has appropriate flexibility or flexibility, and the internal lead 17 is directly connected to the gate electrode. By connecting via the relay terminal 19, which has a large contact area without being connected, it is possible to withstand mechanical and thermal stress applied via the sealing resin.

These stresses are alleviated by the flexibility of the internal lead 17, and the contact area to the gate electrode 15 is increased by the relay terminal 19,
Maintains mechanical strength against tensile stress, etc.

Next, FIGS. 5 and 6 show a second embodiment of the present invention, which is characterized in that a part 27a of the internal gate lead 27 is exposed from the resin sealing part 18. .

That is, the exposed internal lead 27
The purpose is to alleviate mechanical and thermal stress even better by the portion 27a of the structure.

Although this has not yet been fully explained theoretically, the surface of the gate internal lead 27 buried in the resin sealing part 18 also comes into direct contact with the resin, so it is fixed as the resin hardens. However, since the internal lead 27 is formed of twisted wires, the inside thereof is not fixed but can be moved in the length direction. It is understood that stress is absorbed or alleviated in the exposed area.

Note that when filling the case 20 with the sealing resin, the gate internal lead 27 is also pushed into the resin sealing part 18 along with the sealing resin, so in order to avoid this, in this embodiment, the case 20 is Although a support rod 21 extending horizontally is provided in advance in the case 2, this support rod 21 is not necessarily necessary.
It is also possible to use jigs and tools configured to be able to be removed after the sealing resin filled in the sealing resin is cured.

Further, reference numeral 22 in the figure indicates a gate terminal, and other parts that are the same as those in the first embodiment are given the same reference numerals and detailed explanation thereof will be omitted.

Furthermore, although not shown, a conductor pattern is formed on the inner surface of the substrate 11 via an insulating layer, and a necessary circuit is formed.

[Effect of idea]

In this invention, as described above, the internal lead drawn out from the control electrode is composed of a twisted wire made of thin wires.
In addition to imparting flexibility or flexibility, this internal lead is not connected directly to the control electrode, but is connected to the control electrode via a relay terminal having a cross-sectional area larger than the cross-sectional area of the internal lead.
The mechanical strength against tensile stress, etc. is increased, and the flexibility or flexibility can sufficiently absorb and alleviate mechanical and thermal stress, thereby preventing peeling of the internal lead from the control electrode and cutting accidents. It is possible to prevent this and improve the reliability of the device.

[Brief explanation of the drawing]

1 is a partially cutaway sectional view of a conventional semiconductor device, FIG. 2 is a partially cutaway plan view thereof, and FIG. 3 is a partially cutaway sectional view of a semiconductor device showing a first embodiment of the present invention. Figure 4 is a perspective view of the relay terminal used in the above embodiment, Figure 5 is a partially cutaway sectional view showing the second embodiment of the present invention, and Figure 6 is a partially cutaway perspective view of the case used in the above embodiment. It is a diagram. 13... Semiconductor pellet, 15... Gate electrode, 17, 27... Internal lead for gate, 19...
...Relay terminal, 18...Resin sealing part.

Claims (1)

[Claims for Utility Model Registration] (1) A semiconductor pellet having a control electrode, a relay terminal connected to the control electrode, and an internal lead made of a twisted wire formed of thin wires connected to the relay terminal; A semiconductor device characterized by having a resin sealing part in which these parts are sealed. (2) A semiconductor device, wherein a portion of the internal lead is exposed from the resin sealing portion.