Enhancement of p-type conduction in Ag-doped ZnO thin films via Mg alloying: The role of oxygen vacancy

ZnO, ZnMgO, Ag-doped ZnO (ZnO:Ag), and Ag-doped ZnMgO (ZnMgO:Ag) thin films have been prepared by pulsed laser deposition. All the films have a preferred orientation with the c-axis perpendicular to the substrates. Hall-effect measurements indicate that the ZnO:Ag film exhibits p-type conduction, but obviously worse than that of the ZnMgO:Ag film. A comparative study of p-type ZnO:Ag and ZnMgO:Ag films using photoluminescence and x-ray photoelectron spectroscopy measurements shows that the enhanced p-type conduction in ZnMgO:Ag film is closely related to the increase of the activation energy of the intrinsic donors and the suppression of charge-compensating oxygen-related defects after Mg incorporation.

► A comparative study of p-type ZnO:Ag and ZnMgO:Ag films have been performed.
► The ZnMgO:Ag film exhibits an enhanced p-type conduction compared with that of the ZnO:Ag film.
► The enhanced p-type conduction is associated with the suppression of VO after Mg incorporation.
► These results will make for the further understanding on the doping behaviors of p-type ZnMgO.