Modeling of current gain versus recombination in double base epilayer 4H-SiC BJTs

Based on the material characteristics and the carrier recombination theory, the common emitter current gain of the double base epilayer BJTs is modeled and calculated when considering four recombination processes. The results show that the SiC/SiO
2
interface states and the quality of the passivation layer will affect the surface recombination velocity, and make an obvious current gain fall-off at a high collector current.