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).

Keywords

• GaN trench MOSFET
• hafnium dioxide
• power semiconductor devices
• gallium nitride power devices
• high-k gate dielectrics