Influence of preparation methods on photoluminescence properties of ZnO films on quartz glass

The influence of preparation methods on the photoluminescence properties of ZnO film was studied. Two methods were applied to fabricate ZnO films in a conventional pulsed laser deposition apparatus. One is high temperature (500–700 °C) oxidation of the metallic zinc film that is obtained by pulsed laser deposition. The other is pulse laser ablation of Zn target in oxygen atmosphere at low temperature (100–250 °C). The photoluminescence property was detected by PL spectrum. The room temperature PL spectra of the ZnO films obtained by oxidation method show single violet luminescence emission centered at 424 nm (or 2.90 eV) without any accompanied deep-level emission and UV emission. The violet emission is attributed to interstitial zinc in the films. Nanostructure ZnO film with c-axis (002) orientation is obtained by pulsed laser deposition. The ZnO film deposited at 200 °C shows single strong ultraviolet emission. The excellent UV emission is attributed to the good crystalline quality of the film and low intrinsic defects at such low temperature.