Investigations of optical and electrical properties of In-doped GaN films grown by gas-source molecular beam epitaxy

Optical and electrical properties of GaN films grown on alpha-Al2O3(0 0 0 1 ) substrates by GSMBE using In-doping method were investigated. It was foun d that both of them were improved, compared to those of a nondoped GaN one. mu-PL results at 20 K indicated that In-doped films emit luminescence more uniformly than that of a nondoped one. Furthermore. Hall effect measuremen ts at 300 K showed higher electron mobility of In-doped samples than that o f a nondoped one. It is suggested that the presence of In during the growth of GaN films plays a role in reducing the number of structural imperfectio ns to improve the optical and electrical properties. (C) 2000 Elsevier Scie nce B.V. All rights reserved.