Influence of Energetic Oxygen Bombardment on Conductive ZnO Films

Abstract

Conductive ZnO films were prepared by DC planar magnetron sputtering and DC diode sputtering, and the reason for the high resistivity shown by the films at the substrate positions facing the eroded area of the target was investigated. It was found that bombardment of the film by energetic O atoms or O^-ions is responsible for the high film resistivity, since this results in a decrease in both the carrier mobility and the carrier concentration. The arrival of excess O atoms and O^-ions with relatively lower energies also induces an increase in the film resistivity as a result of a decrease in carrier concentration. The positional dependence of the film resistivity is explained by considering the above two factors.