Annealing effect on properties of Zno thin films grown on LiNbO_3 substrates by MOCVD

摘要

ZnO films were grown on (0001) LiNbO_3 substrates by metal organic chemical vapor deposition (MOCVD). Annealing of ZnO films was performed in air for 1 h at 800℃. The effects of annealing on the structural and optical properties of ZnO thin films on LiNbO_3 substrates were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM) and photoluminescence (PL) measurements. XRD patterns and AFM showed that the as-grown and the annealed ZnO films grown on LiNbO_3 substrates had c-axis preferential orientation, the crystallinity of the ZnO films grown on LiNbO_3 substrates was improved, and the grain size increased by annealing. The PL spectra showed that the intensity of the UV near-band-edge peak was increased after annealing, while the intensity of visible peak (deep-level emission) decreased.