4H-SiC work-function-dependent bipolar transistor with ultra-high current gain

A new structure of a 4H-SiC bipolar transistor with ultra-high current gain is proposed and analysed by simulation. A p-type Schottky contact serving as the conventional emitter region is introduced. By proper choice of the metal work-function, the injection efficiency of the minority carrier (electron) is promoted and may be close to unity. Therefore high current gain is realised due to the high electron current density injected from the p-type Schottky contact. The simulation results show that the current gain varies with the metal work-function and could reach ~1000, which is attractive for the base-drive circuit. Moreover, the new structure simplifies the etching process compared with the conventional bipolar junction transistor.