Characterization of high-voltage charge-trapping effects in GaN-based power HEMTs

We investigate the effects and the causes of highvoltage charge-trapping phenomena in AlGaN/GaN Schottky-HEMTs grown on SiC substrate, and we present an high-voltage pulsed system, implemented by a cost-effective fully-customable modular solution. The characterization methodology includes double-pulsed I_D-V_D measurements, time-resolved R_ON recovery transients, and leakage-currents analysis. The observed parasitic dynamic R_ON-increase is triggered by high drain-voltage (>50V), and likely originates from the trapping of parasitic electrons supplied by leakage currents at the crystallographic defect-states located within the epitaxial structure.