Semiconductor integrated circuit with switching bipolar transistors

Abstract

A semiconductor device is primarily composed of a semiconductor substrate of a first conductivity type and a semidonductor layer of a second conductivity type formed in a principal plane of the semiconductor substrate. The device has both a bipolar transistor with the semiconductor layer itself being the collector region. The base region is of the first conductivity type and the emitter region is of the second conductivity type. Both regions are formed in the same layer as a JFET struture which includes the above collector region as channel a and the above base region as a gate. A semiconductor region of the first conductivity type is formed in the above semiconductor layer, the semiconductor layer itself, and the above base and emitter regions constitute a thyristor structure.