The microstructure and defects of as-grown and annealed ZnO/Si thin films were investigated by high-resolution transmission electron microscopy. The cross-sectional bright-field transmission electron microscopy images showed that the ZnO thin films consisted of columnar grains. The selected-area electron diffraction pattern showed that the ZnO/Si thin film were c-axis oriented and the deviation angle along the ZnO (00•1) direction with respect to the growth direction was no more than 5°. The grain boundaries could be classified into three types: low-angle boundaries, boundaries near a 30° angle with (10•0) facet structures and large-angle boundaries. In addition to grain boundary, the as-grown and annealing processing defects were also investigated by high-resolution transmission electron microscopy. The crystal quality of the ZnO/Si thin films could be improved by annealing at 600C. However, at too high an annealing temperature of 800C, the newly produced processing defects such as three-layer stacking fault and double stacking fault were formed.

Microstructure and Defect Investigations of the As-Grown and Annealed ZnO/Si Thin Films. Huang, J., Lu, H., Ye, Z., Wang, L., Zhao, B., He, H.: Journal of Applied Physics, 2007, 102[5], 053521