Properties of Sn-Doped Indium Oxide Prepared by High Rate and Low Temperature RF Sputtering

An rf sputtering apparatus with magnetic plasma containment was used to deposit indium-tin oxide film onto glass substrates at low temperatures (140–180°C) and at various deposition rates (700–5000 Å/min). Determinations of resistivity, optical transmission and reflection, and crystal structure were made both for the as-deposited films and the annealed films. X-ray diffraction measurements of the films revealed amorphous-like structure in the as-deposited states, and crystalline structure with preferred orientation in the annealed states. The amorphous-like films deposited at a rate below 2000 Å/min exhibited high visible transmission, high infrared reflection, and low resistivity similar to those for the annealed films deposited at a rate above 4000 Å/min. The optical and electrical properties of the as-deposited and annealed films were strongly dependent on deposition rate.