JPS593969A - Amplification gate type gate turn off thyristor - Google Patents

Abstract

PURPOSE:To obtain an amplification gate type GTO of good gate characteristic by a method wherein only the main GTO part is formed in the structure of anode-emitter (PE) short circuit, and only the amplification gate part is doped with lifetime killer. CONSTITUTION:The amplification gate parts of a P-layer 2B, an N-layer 3, and a P-layer 4 are doped with the lifetime killer 6, and the amplification gate parts are not formed in the structure of PE short circuit. The main GTO part is in the structure of PE short circuit and has no dope of lifetime killer. Cathode electrodes are formed on N-layers 5A, and while gate electrodes are formed on the P-layer 4, etc. When only the main GTO part is formed in the structure of PE short circuit, and only the amplification gate part is doped with lifetime killer, the gate current IGT becomes at a suitable value that it is neither oversized nor undersized, and accordingly the cause of error ignition in a turn off period is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an amplification gate type gate turn-off thyristor,
In particular, it relates to the improvement of its gate characteristics.

As is well known, gate turn-off thyristor (hereinafter referred to as GT
(abbreviated as O) has a self-extinguishing function.In order to improve the turn-off characteristics, it is doped with heavy metals such as gold to make it a lifetime killer9, or the anode emitter (Pl) layer is made into a short-circuit structure. There are things to do.

The former has the advantage of reducing the turn-off time, but also has many disadvantages such as an increase in on-voltage and an increase in leakage current. On the other hand, in the latter case, the current amplification factor αp of the pnp transistor section is suppressed to a small value, and at turn-off, excess carriers accumulated in the N1 layer are swept out through the short-circuited part of the 21st layer. It is possible to reduce on-voltage and leakage current.

By the way, even if an amplification gate structure is effective for reducing the on-gate current, a problem arises if the amplification gate type GTO is made into a P1 short-circuit structure and the lifetime killer is not fully doped. That is, if the amplification gate section has a Pm short-circuit structure like the main GTQ section, the minimum gate current Gτ required for turn-on will increase, and the advantages of the amplification gate structure will be impaired. Furthermore, if only the main GTO section has a Pm short-circuit structure, Xar becomes too small, which causes erroneous ignition at turn-off.

The present invention has been made in consideration of the above points, and the main GTO
The object of the present invention is to provide an amplification gate type GTOi with good gate characteristics by making only the amplification gate part have a Pm short-circuit structure and doping only the amplification gate part with a lifetime killer.

Hereinafter, the present invention will be described in detail based on illustrated examples.

The drawing shows one embodiment of the present invention, where 1 is a reinforcing tungsten plate, 2 people and 2B are P layers (anode emitters).
, 3 is an N layer, 4 is a P layer, 5 and 5B are cathode emitters, and a PNPN layer is formed on the tungsten plate 1. 2 layers 2B.

The amplification gate portions of the N layer 3 and the P layer 4 are doped with a lifetime killer 6. This amplification gate section does not have a PIC short m structure. Further, the main GTO section has a Pm short-circuit structure and is not doped with a lifetime killer.

Note that a cathode electrode is formed on the N layer 5A, and a gate electrode is formed on the P layer 4 and the like.

As mentioned above, in the amplified gate type GTO, the main GT
If only the O part has a P, short-circuit structure, and only the amplification gate part is doped with a lifetime killer, the gate current structure GT
is an appropriate value that is neither too large nor too small, and the cause of false firing during the turn-off period is eliminated.

For example, if the main GTO part has a Pa short-circuit structure and is not doped with a lifetime killer, and the amplification gate part is not a Pm short-circuit structure and is not doped with a lifetime killer, the gate current IGT would be 50 InA. On the other hand, when only the increased gate portion was doped with lifetime killer (Au840C 30 min) I as in this example, the gate current EaT was 300 WIA.

As described above, according to the present invention, the main GTO section has a Pya short-circuit structure and is not doped with a lifetime killer, and the amplification gate section has a Pm short-circuit structure and is doped with a lifetime killer, which is necessary for turn-on. The minimum gate current flow GT is an appropriate size, and there is no possibility of erroneous firing during the turn-off period.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view showing an embodiment of an amplification gate type GTO according to the present invention. 11 Reinforcement Turngesten plate, 2A and 2B...Anode emitter, 3...N layer, 4...P layer, 5A and 5B...Cathode emitter, 6...Lifetime key 710

Claims (1)

[Claims] In a gate turn-off thyristor with an amplification gate structure, only the main thyristor part has a Pit short-circuit structure, and a lifetime killer is installed only in the amplification gate part. - An amplification gate type gate turn-off thyristor characterized by a double-circuit.