Structural, dielectric, and electrical studies on thermally evaporated CdTe thin films

Sandwich structures of cadmium telluride (CdTe) thin films between Ag electrodes were prepared by thermal evaporation technique at a vacuum of ~2 × 10⁻⁵ torr. Structural characterization of these thin films was performed using X-ray diffraction (XRD) studies. The effect of temperature and frequency on the electrical and dielectric properties of these films was studied in detail and reported in this article. The experimental study indicates that for the CdTe thin film the dielectric constant and dielectric loss increases with temperature and decreases with frequency. However, A.C. conductivity increases both with temperature and frequency. The data of complex impedance measurements over the same range of temperature and frequency are used to describe the relaxation behavior of the CdTe film. Our results indicate that the transport behavior of carriers in CdTe thin films is consistent with the correlated barrier hopping (CBH) model.