The effects of intrinsic defects on the structural and optical properties of ZnO thin film prepared via a sol-gel method

The ZnO thin-film was prepared via a sol-gel method, followed by an annealing process in the different atmospheres (O-2, Ar and H-2, respectively), and the intrinsic defects related structural and optical properties were investigated. An enhancement of the interstitial Zn (Zn-i) and O vacancy (V-O) defect concentrations was achieved for the samples annealed in an Ar and H-2 atmospheres, which was identified by the XRD and photoluminescence (PL) measurements. And an improvement of the interstitial O (O-i), Zn vacancy (V-zn) and anti-site O (O-Zn) defect concentrations was observed for the sample annealed in an oxygen-rich condition. Furthermore, some defects-related PL characteristics were also examined, and the clearly identifications were shown as below: Zn-i (435 nm), VO (457 nm), O-Zn (500 nm), O-i (562 nm), V-Zn (655 nm), and the electron transition from the ionized Zn-i to O-i (620 nm).