Electrical properties and Raman scattering investigation of Ag doped ZnO thin films

Ag-doped ZnO thin films were deposited on quartz glass substrates by a radio-frequency (RF) magnetron sputtering technique at room temperature (RT). The influence of Ag doping content on the electrical and Raman scattering properties of ZnO films were systematically investigated by Hall measurement system and Raman scattering spectrum. Two additional local vibrational modes (LVMs) at 230.0 and 394.5 cm−1 induced by Ag dopant in ZnO:Ag films were observed by Raman analyses at RT, corresponding to Ag atoms located at O sites (LV MZn−Ag) and Zn sites (LV MAg−O) in ZnO lattice. Moreover, we further studied the effect of donor AgO and acceptor AgZn defects on the electrical properties of ZnO:Ag films. The results indicate that O-rich condition is preferred to suppress the formation of AgO defects and enhance AgZn defects. The p-type ZnO:Ag film was achieved by properly optimizing the annealing conditions under O-rich condition.

► Ag doped ZnO thin films.
► Two additional LVMs (LV MZn−Ag and LV MAg−O) were observed under Zn-rich condition.
► O-rich condition is preferred to suppress the formation of AgO and enhance AgZn.
► The p-type ZnO:Ag film was achieved under O-rich condition.