Dependence of the mechanism of current flow in the in-n-GaN alloyed ohmic contact on the majority carrier concentration

Abstract

Based on the study of the temperature dependence of resistance of the In-n-GaN alloyed ohmic contacts, it is found that the mechanism of current flow in them substantially depends on the concentration N of uncompensated donors in GaN. At N = 5 × 1016 − 1 × 1018 cm−3, current mainly flows along the metallic shunts, and at N ⩾ 8 × 1018 cm−3 it flows by tunneling.