Transient processes in high-voltage silicon carbide bipolar-junction transistors

The specific features of transient processes in high-voltage silicon carbide bipolar-junction transistors are studied theoretically and experimentally. It is shown that, in good agreement with the experimental results, the switch-off from the active mode can be described in a wide temperature range by the simple analytical expression derived in the study. The process in which a transistor is switched on to pass into the active mode is well described by a simple exponential dependence. The time constant of the switch-on process is determined by the average value of the collector capacitance before and after switch-on. A numerical model is suggested, based on a simple and physically transparent equivalent circuit describing, in good agreement with the experiment, both the transient processes of switch-on and switch-off in a SiC bipolar junction transistor, in both the active and saturation modes.