Improvement In Electrical Characteristics Of Low-Pressure Chemical-Vapor-Deposited Sinx Dielectric Layer On Gan Substrate By Ammonium Sulfide Treatment

The electrical characteristics of low-pressure chemical-vapor-deposited SiNx on GaN and ammonium sulfide-treated GaN substrate were investigated. Upon ammonium sulfide treatment, the leakage current densities of SiNx/GaN were reduced from 1.82 x 10(-9) to 2 x 10(-10) A/cm(2) and from 4.44 x 10(-9) to 1.6 x 10(-9) A/cm(2) under electric fields of +/- 1 MV/cm, respectively. The negative effective oxide charges were improved from -1.39 x 10(13) to -4.1 X 10(12) C/cm(2). The ammonium sulfide treatment improves the interface and film qualities of SiNx/GaN. (c) 2009 The Japan Society of Applied Physics