Effect of very low power inductively coupled plasma etching on ohmic contacts to p-GaN

Abstract

We report on the electrical characterisation of etched Mg-doped p-GaN layers using low power inductively coupled plasma reactive ion etching (ICP-RIE). Although the quality of ohmic contacts to p-GaN is generally degraded by plasma etching, the results, assessed by current-voltage characteristics and Transmission Line Model (TLM) analysis, indicate that the ohmic contacts improve significantly as the power is reduced from ICP/RF power of 150/75 W to very low ICP/RF power of 40/20 W.