Transparent conductive ZnO film preparation by alternating sputtering of ZnO:Al and Zn or Al targets

Multilayered ZnO:Al and ZnO:O-v film was prepared by alternately sputtering ZnO:Al(2% wt.) and Zn targets. The films obtained were optically transparent and had lower resistivity than those prepared by ZnO:Al sputtering. Deposition from the Zn target gave a ZnO film containing native donors (a ZnO:O-v film). The carrier concentration increased in the ZnO:Al/ZnO:O-v multilayered film. Our results cannot be explained by the redistribution of the carrier between ZnO:Al and ZnO:O-v. This result indicates an improvement in the doping efficiency. Multilayered films of ZnO:Al and Al oxide compounds were also prepared. In this case, with increasing thickness of the Al oxide film, a decrease was observed in the carrier mobility, due to the scattering at the interface. (C) 1998 Elsevier Science S.A. All rights reserved.