Enhancement-Mode GaN p-Channel MOSFETs for Power Integration

We present systematic characterizations of enhancement-mode (E-mode) GaN p-channel MOSFETs (p FETs) fabricated on a commercially available p-GaN gate highelectron-mobility-transistor (HEMT) wafer that is intended for power electronics applications. The E-mode GaN p-FETs were realized with a gate process that features moderate recess and subsequent oxygen plasma treatment, yielding a buried channel away from the gate-oxide/GaN interface. The p-FETs exhibit a good balance among negative threshold voltage (for E-mode operation), current density, ON/OFF ratio and subthreshold swing, exhibiting promising performance for monolithically integrated GaN complementary logic circuits that would provide on-chip energy-efficient gate driving and control circuits for the p-GaN gate power HEMTs. A GaN complementary logic inverter featuring an E-mode GaN p-FET and an E-mode p-GaN gate n-FET is demonstrated with negligible static power consumption and rail-to-rail operation.