Gate controlled bidirectional semiconductor switching device having two base regions each having a different depth from an adjacent surface

摘要

A gate-controlled bidirectional switching device has two main terminals on opposite major surfaces of the device. A single gate terminal located adjacent one of the main terminals on one of the major surfaces receives a signal biased with respect to said one terminal to trigger the device into conduction. The device conducts current in either direction through the main terminals, depending on the polarity of an applied bias potential across the main terminals. By controlling the resistivities or the widths of two base regions in the device with respect to each other, a trigger current for switching the device from a nonconductive state to conduct current in the one direction is adjusted with respect to that required to switch the device to conduct current in the other direction.