15 kV n-GTOs in 4H-SiC

摘要

High performance 15 kV n-GTOs were demonstrated for the first time in 4H-SiC. The device utilized a 140 μm thick, lightly doped n-type drift layer, with 1450°C lifetime enhancement oxidation, which resulted in a carrier lifetime of 17.5 μs. The p~(+) backside injector layer was thinned to minimize parasitic resistances. A room temperature forward voltage drop of 5.18 V was observed at a current density of 100A/cm~(2). A 1 cm~(2) device showed a leakage current of 0.17 μA at 15 kV. The 4H-SiC n-GTO showed latching characteristics, and showed a turn-off time of 170 ns in a resistive load switching setup, which represents about a factor of 45 improvement in turn-off speed over 4H-SiC p-GTOs with comparable voltage and current ratings.