Ethylene for carbon doping of GaN by atmospheric pressure metal organic chemical vapor deposition

Abstract

The carbon incorporation properties of GaN from ethylene and trimethylgallium precursors was studied by atmospheric pressure metal organic chemical vapor deposition. It is found that V-III ratio was the main restriction factor for carbon incorporation. Carbon concentration could be regulated effectively one order of magnitude by tuning V-III ratio for C2H4 doped GaN, and would be enhanced at relatively low V-III ratio for self-doped GaN. Low threading dislocation density and atomic flat surface of C2H4 doped GaN films was kept even if carbon doping concentration of 9E18/cm3 compared with UID-GaN and a high breakdown voltage of 2278 V at leakage current of 10µA was obtained in C2H4 doped GaN buffer layer.