Defects, stress and abnormal shift of the (002) diffraction peak for Li-doped ZnO films

摘要

The effect of changes in Li content on the structural property of sol-gel Li-doped ZnO films was investigated in this study. The observed changes of the Li incorporation-induced strain along c-axis are closely related to the different ratios between the concentrations of Li interstitials (Lij) and Li substituting for Zn (Li_(Zn)) in the films. According to the observed results from X-ray diffraction (XRD) and photolumines-cence measurements, we found that the domination of the dissociative mechanism in the Li-doped ZnO films led to transformation from li_(Zn) to Li_i, involving the formation of Zn vacancies (V_(zn))- In addition, the interaction between these defects (that is, Li_(Zn), Li_i, V_(zn) and oxygen vacancy) and the crystal structure may lead to the abnormal shift of the (002) diffraction peak position determined from XRD measurements.