Metal-oxide barrier extraction by Fowler-Nordheim tunnelling onset in Al2O3-on-GaN MOS diodes

Investigation of the properties of Al₂O₃-on-GaN metal-oxide-semiconductor diodes is reported. A new method is shown to calculate the metal-oxide barrier height based on the onset of the Fowler-Nordheim tunnelling current regime in direct bias. The Ni/Al₂O₃ barrier was extracted, for the first time with this method, and it was found to match other reports in the literature. The dependence of the effectiveness of this method on the oxide thickness is discussed. The breakdown field for Al₂O₃ was also measured and found to be in agreement with previous reports.