Inversion behavior in Sc2O3/GaN gated diodes

Abstract

The capacitance–voltage (C–V) characteristics of Sc2O3/p-GaN gate-controlled diodes show unusual hook shapes due to the charging of surface states. From the drain–voltage dependence of the C–V curves, the total surface state density was estimated to be ∼8.2×1012 cm−2 for diodes undergoing an implant activation anneal at 950 °C. The accumulation capacitance showed a significant dependence on measurement frequency and is suggested to result from the presence of an interfacial dielectric between the Sc2O3 and GaN. The Si-implanted n+ regions in the gated diode structure are effective in providing a source of inversion charge.