Transparent p-type conducting a sandwich structure Al/SnO2/Al multilayer thin films deposited on quartz substrate have been prepared by RF sputtering method using SnO2 (99.99%) and Al (99.99%) targets. In order to study the effect of thermal diffusing temperature and time on the structural, electrical and optical performances of Al/SnO2/Al films, the deposited films were annealed at different temperatures for different durations, respectively. X-ray diffraction results show that all p-type conducting films possessed polycrystalline SnO2 with tetragonal rutile structure. The microstructure, Hall effect and optical property were checked by FE-SEM, Hall effect measurement and UV–Visible absorption spectra. As the annealing temperature increases, the transparence (%) and energy band (Eg) increase. Especially, Hall effect results indicate that 450 οC for 4 hrs were the optimum annealing temperature for the resistivity (Ω·cm) with a relatively high hole concentration of 2.09 × 1019 cm-3 and a low resistivity of 5.38 × 10-1 Ω · cm.

Keywords: TCOs, SnO2, RF Sputtering, Annealing, Multi-layer