Ga2O3 Schottky barrier and heterojunction diodes for power electronics applications

Abstract

We present novel approaches for the development of Ga₂O₃ Schottky barrier and heterojunction diodes. Samples of β- Ga₂O₃ were first annealed in N₂ and O₂ to demonstrate the effect of annealing on the carrier concentration. Cathodoluminescence and electron spin resonance measurements were also performed. Schottky barrier diodes on asgrown and O₂-annealed epitaxial Ga₂O₃ films were fabricated and breakdown voltages were compared. Lower reverse current and a breakdown voltage of about 857 V were measured on the O₂-annealed device. Finally, we report preliminary results from the development of anisotype heterojunctions between n-type Ga₂O₃ with a sputtered NiO layer. Rectifying current-voltage characteristics were obtained when the NiO was deposited both at room temperature and at 450 °C.