HfO2‐insulated gate N‐polar GaN HEMTs with high breakdown voltage

In this paper, we present the first demonstration of a HfO2‐insulated gate N‐polar GaN inverted high‐electron‐mobility transistor (iHEMT). HfO2‐insulated gate devices showed an order of magnitude improvement in reverse‐bias gate leakage current as compared to reference Schottky devices. With the reduced gate leakage current, the insulated gate iHEMTs were able to simultaneously demonstrate breakdown voltages in excess of 130 V and maximum current density of 0.87 A/mm. Pulsed I–V gate‐lag measurements were performed to investigate the drain current transient behavior of these devices.