Schottky barrier height and contact resistivity reduction of metal/GaOx/n-GaN structure

Abstract

The purpose of this paper is to obtain the low contact resistivity on n-GaN. We adopted metal-insulator-semiconductor (MIS) contact for relaxing Fermi level pinning. Especially, in the case of thermally grown GaOx for insulator and Mg30nm/Al 220nm for metal, we obtained the contact resistivity as small as 3.7×10−7 Ω·cm2 on n-GaN having Si doping concentration of 2 × 1018 cm−3. The low contact resistivity was made possible by lowering the Schottky barrier height by the presence of the thin GaOx insulator at metal/n-GaN interface.