Patent
1981-12-11
1987-01-27
Carroll, J.
357 34, 357 46, 357 51, 357 68, H01L 2972, H01L 2702, H01L 2348
Patent
active
046397574
ABSTRACT:
In a semiconductor device a power transistor is equipped with a ballast resistance formed in the same semiconductor layer which forms the emitter regions which perform the bipolar transistor operation. Due to this ballast resistance and an electrode extension portion also formed in the emitter semiconductor layer, an undesirable parasitic transistor is also formed in the semiconductor device. This parasitic transistor is comprised of an emitter formed by the ballast resistor and the electrode extension portion, and the base and collector regions of the bipolar transistor layers which are immediately below the ballast resistor and the electrode extension portion. Accordingly, means are disposed in the layer forming the base region for reducing the current gain of the parasitic transistor. This current gain reducing means can include either an expanded width base portion or a higher impurity concentration base portion in the parasitic transistor region.
REFERENCES:
patent: 3358197 (1967-12-01), Scarlett
patent: 3609460 (1971-09-01), Ollendorf
patent: 3704177 (1972-11-01), Beale
patent: 3810123 (1974-03-01), Baitinger et al.
patent: 3884732 (1975-05-01), Baitinger et al.
patent: 3913123 (1975-10-01), Masaki et al.
patent: 4049975 (1977-09-01), Colaco
patent: 4149177 (1979-04-01), Alter
patent: 4151540 (1979-04-01), Sander et al.
patent: 4315271 (1982-02-01), Roger
Carroll J.
Hitachi , Ltd.
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