GaN-based p-type metal-oxide-semiconductor devices with a gate oxide layer grown by a bias-assisted photoelectrochemical oxidation method

In this work, a bias-assisted photoelectrochemical (PEC) oxidation method was used to form an oxide insulator for GaN-based p-type metal-oxide- semiconductor (MOS) devices. The inversion breakdown and accumulation breakdown fields of the resulting GaN p-type MOS devices were 11.6 MV cm^-1 and 3.7 MV cm^-1, respectively. The interface-state density of the GaN p-type MOS devices was 4.18 × 10¹¹ cm^-2 eV ^-1 obtained by a photo-assisted capacitance-voltage measurement method. In addition, the negative fixed oxide charge of 2.4 × 10 ¹² cm^-2 eV^-1 was also estimated.