The effect of oxygen vacancies upon the defect-related emission and the electronic properties of In2O3 nanowires was reported. The nanowires were synthesized by vapour phase transport and had diameters ranging from 80-100nm and lengths over 10-20μm, with a growth direction of [001]. The as-grown nanowires connected in an FET type of configuration show n-type conductivity, which was ascribed to the presence of intrinsic defects like oxygen vacancies in the nanowire. The resistivity, transconductance, field effect mobility and carrier concentration of the In2O3 nanowires were determined to be 1.82 x 10−2Ω cm, 11.2nS, 119cm2 V−1 /s and 4.89 x 1017/cm3, respectively. The presence of oxygen vacancies was also confirmed by photoluminescence measurements, which show a strong UV emission peak at 3.18eV and defect peaks in the visible region at 2.85, 2.66 and 2.5eV. A technique of post-growth annealing in O2 environments, and passivation with (NH4)2S to reduce defect-induced emission, was presented.

Role of Oxygen Vacancies in Visible Emission and Transport Properties of Indium Oxide Nanowires. P.Gali, F.L.Kuo, N.Shepherd, U.Philipose: Semiconductor Science and Technology, 2012, 27[1], 015015