Dependence of film thickness on the electrical and optical properties of ZnO-Cu-ZnO multilayers

ZnO-Cu-ZnO multilayers were prepared by simultaneous RF magnetron sputtering of ZnO and DC magnetron sputtering of Cu. Cu films with different thickness were used as the intermediate metal layer. The optical and electrical properties of the multilayers studied by UV-vis spectrophotometer and four point probe method, respectively, shows that transmittance increases with decrease of copper thickness up to an optimum thickness of 5 nm and sheet resistance decreases with increase of thickness. Low resistivity and high transmission were obtained when the film structure has a thickness of ZnO/Cu/ZnO: 50/5/50 nm. The performance of the multilayers as transparent conducting material was better than the single layer ZnO of equal thickness.