A New High Speed Switching Bipolar Power Transistor with Corrugated Base Junctions

A new structure of the bipolar power transistor with corrugated base junctions is proposed for fast switching applications. The proposed bipolar power transistors with corrugated base junctions are fabricated without any additional process steps. We investigated the electrical characteristics of the transistor such as current gain, saturation voltages between the collector and the emitter and turn-off transient times, and compared them with those of the conventional bipolar transistors with parallel plane base junctions. It is shown that the bipolar transistors with corrugated base junctions have not only shallow saturation but also built-in field accelerating the recombination of excess electrons and holes in the base region. The storage times of the bipolar power transistors with corrugated base junctions are shorter by above 25% than those of the conventional bipolar power transistors.