(1) The Research and Development Division, Alti-electronics Co., Ltd, Yongin, 449-882, South Korea;(2) Department of Electrical & Semiconductor Engineering, Chonnam National University, Yosu, 550-749, South Korea;
Abstract:
Ga-doped ZnO films were prepared at 10 mTorr of oxygen over a broad temperature range using pulsed laser deposition. The carrier concentration of as-deposited films decreased monotonically with deposition temperature over a temperature range of 25°C to 450°C. Post-deposition annealing of as-deposited films in forming gas (5% H2 in argon) or vacuum resulted in a substantial increase in both carrier concentration and electron mobility. The figure of merit was highest for films deposited at 250°C then annealed in forming gas at 400°C. The optical transmittance was near 90% throughout the visible and near-infrared spectral regions. These results indicate that Ga-doped ZnO is a viable alternative to transparent indium-based conductive oxides.