Positive Temperature Coefficient SiC PiN Diodes

Abstract

Integration of patterned ballast resistance into the anode of SiC PiNs is a solution to the dilemma of negative dVf /dT for such diodes. In fabricated 4H-SiC PiN diodes, we demonstrate a cross-over from negative to positive temperature coefficient for current densities as low as 80 A/cm2. Adjusting the percentage of the patterned anode area, the positive or neutral dVf /dT can be achieved over a wide current-density range without substantial penalty in the forward voltage drop. This characteristic is crucial for high-power SiC packages with ganged-parallel rectifier arrays.