2.2 kV SiC BJTs with Low VCESAT Fast Switching and Short-Circuit Capability

Abstract

This paper reports large active area (15 mm2) 4H-SiC BJTs with a low VCESAT=0.6 V at IC=20 A (JC=133 A/cm2) and an open-base breakdown voltage BVCEO=2.3 kV at T=25 °C. The corresponding room temperature specific on-resistance RSP-ON=4.5 mΩcm2 is to the authors knowledge the lowest reported value for a large area SiC BJT blocking more than 2 kV. The on-state and blocking characteristics were analyzed by device simulation and found to be in good agreement with measurements. Fast switching with VCE rise- and fall-times in the range of 20-30 ns was demonstrated for a 6 A 1200 V rated SiC BJT. It was concluded that high dynamic base currents are essential for fast switching to charge the BJT parasitic base-collector capacitance. In addition, 10 μs short-circuit capability with VCE=800 V was shown for the 1200 V BJT.