On the physical properties of In2O3 films grown on (0001) sapphire substrates by atomic layer deposition

Abstract

The properties of In2O3 films grown on (0001) plane sapphire substrates by atomic layer deposition using trimethylindium and nitrous oxide were investigated. Using x-ray diffraction and scanning and transmission electron microscopies, In2O3 films were found to deposit on sapphire substrates with their (222) planes parallel to the (0001) planes of sapphire. It was found that there were twin structures inside the In2O3 film with twin boundaries along the {11 (2) over bar} planes. Most In2O3 films deposited on thermally annealed low-temperature-In2O3 buffer-layer-coated substrates exhibited high optical transmittance, low electron concentration, and high electron mobility. The best In2O3 film achieved shows an average transmittance of similar to 90% in the visible regime with electron concentration and mobility being similar to 2 x 10(16) cm(-3) and similar to 60 cm(2)/V s, respectively, at room temperature. (C) 2011 American Vacuum Society. [DOI: 10.1116/1.3549146]