The improvement of Al2O3/AlGaN/GaN MISHEMT performance by N2 plasma pretreatment

This paper discusses the effect of N2 plasma treatment before dielectric deposition on the electrical performance of a Al2O3/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MISHEMT), with Al2O3 deposited by atomic layer deposition. The results indicated that the gate leakage was decreased two orders of magnitude after the Al2O3/AlGaN interface was pretreated by N2 plasma. Furthermore, effects of N2 plasma pretreatment on the electrical properties of the AlGaN/Al2O1-x interface were investigated by x-ray photoelectron spectroscopy measurements and the interface quality between Al2O3 and AlGaN film was improved.