The effect of annealing temperature on the properties of ZnO films with preferential nonpolar plane orientation by SSCVD

Abstract

The effect of annealing temperature on the structural morphology and optical properties of preferential nonpolar plane orientated ZnO thin films on Si (100) substrates by single source chemical vapor deposition (SSCVD) was investigated. The structural and morphological properties of the films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) measurements respectively. All the ZnO films annealed at the selected temperatures (500–800 °C) exhibiting a–b axis orientation, but with preferential nonpolar (100) plane orientation. It is found that the intensity of the (100) peak depends strongly on the annealing temperature, while that of (101) peak shows a variation in a very small scale. The surface morphology demonstrates that the film is of the uniform grains except for that annealed at 800 °C, for the aggregation of the ZnO particles occurred. The film shows a superior smooth surface annealed at 600 and 700 °C in comparison with other thermal annealed. It is also found from the photoluminescence(PL) measurements that the film annealed at 700 °C exhibits the lowest deep-level emission(DLE). However, the intensity of the near band edge emissions (NBE) and DLE show a wavelike variation, which are consistent to the variation of the intensity of (100) peak in the XRD results.