Impact of Carriers Injection Level on Transients of Discrete and Paralleled Silicon and 4H-SiC NPN BJTs

The 4H-SiC vertical NPN BJTs are attractive power devices with potentials to be used as high switching voltage ratings in range of 1.7 kV and operating temperatures. In this paper, the advantages terms transients current gain over their silicon counterparts is illustrated by means extensive experimental measurements modelling, including investigation level injection, a common phenomenon bipolar that influences rates DC gain. two device types have been tested at 800 V maximum temperature 175 °C collector 8 A. turn-ON turn-OFF transition Silicon BJT seen much slower than SiC while transient duration will increase increasing decreases larger currents. common-emitter also found higher counterparts, low injection levels but decreasing both devices. rate slows down toward stability increases, known high-level injection. Current sharing imbalance among parallel connected investigated, which shown evidently dependant on base resistance BJT, collapse resistance. delay single paralleled almost non-existent device.