High current density 1.2 kV class HfO₂-gated vertical GaN trench MOSFETs

Abstract This work reports on high current density 1.2 kV class HfO 2 -gated vertical GaN trench metal-oxide-semiconductor field-effect transistors (MOSFETs). An output current density of 330 mA mm −1 is reported at a drain bias of five volts, which, to our knowledge, is over ten-times the highest reported values for 1.2 kV class GaN or SiC MOSFETs. This work also showcases a significant achievement in demonstrating substantially thick (100 nm) HfO 2 on GaN with simultaneous low leakage current (0.5 nA at 2 MV cm −1 ), a high breakdown strength (5.2 MV cm −1 ), and a high recorded dielectric constant (22.0).