Properties of transparent zinc-stannate conducting films prepared by radio frequency magnetron sputtering

Highly transparent and conductive amorphous zinc-stannate thin films were prepared by rf magnetron sputtering using a target with a Zn/(Zn+Sn) content of 33 at. %. The resistivity distribution of the zinc-stannate films having a composition near ZnSnO3 and deposited on the surface of substrates placed parallel to the target surface was successfully controlled by optimizing both the sputter gas pressure and oxygen partial pressure. A uniform distribution with a resistivity of 4–5×10−3 Ω cm and an average transmittance above 80% in the visible range was obtained for undoped zinc-stannate films deposited on substrates from room temperature to 300 °C. The zinc-stannate films were found to be thermally and chemically more stable than undoped SnO2 and ZnO films.