Substrate temperature dependent variation in the properties of cadmium telluride thin films deposited on glass

The present study relates to the variation in properties of cadmium telluride (CdTe) thin films deposited via electron beam and thermal vacuum evaporation methods at two different substrate temperatures. The influence of substrate temperature on structural, morphological, optical and electrical properties of CdTe thin films is investigated. For structural characterization, grazing incidence X-ray diffraction technique is used which revealed that thin films deposited at 200 degrees C temperature are more crystalline in nature as compare to the room temperature. The parameters such as average crystallite size (D), lattice strain (epsilon), number of crystallites per unit area (N) and texture coefficient TC (hkl) were calculated for both types of synthesized CdTe thin films. Surface morphology of thin films was recorded using scanning electron microscopy and found to be homogeneous in nature. The optical studies carried out using UV-Visible Spectrophotometer and Photoluminescence shown a decrease in band gap values for both electron beam and thermally deposited thin films samples at 200 degrees C substrate temperature. Electrical measurements recorded using two probes method showed the maximum value of current for CdTe thin films deposited by electron beam evaporation method at 200 degrees C substrate temperature.