Effects of O2/Ar Ratios on the Structure and Photoluminescence of ZnO Thin Films Prepared by Magnetron Sputtering

ZnO thin films were deposited on glass substrates by the reactive radio-frequency magnetron sputtering with different O2/Ar ratios. The phase compositions and morphology of the ZnO thin films were analyzed by XRD and AFM. The room-temperature photoluminescence(PL) of ZnO films were measured by fluorescence photometer. The results show that when the O2/Ar ratio was 7∶5, the prepared ZnO thin film had the best crystallization quality with fine and homogeneous grain structure. The violet, blue and green peaks were observed on the PL spectra. With the increase of O2/Ar ratio, the blue emission was enhanced, while the violet and green emission was increased first and then decrease, and when the O2/Ar ratio was 7∶5, the violet and green emission intensity was the strongest.