Effect of heat treatment on optical properties of Cadmium Zinc Telluride thin films grown by cathodic radiofrequency sputtering

In this paper, the Cadmium zinc telluride thin films were prepared by cathodic radio frequency sputtering from cadmium telluride and zinc telluride targets. The films deposited on glass substrates were annealed in vacuum at different temperatures (300 degree C-400 degree C). Structural properties of Cadmium zinc telluride were studied using X-ray diffraction. The effects of heat treatment temperature on the optical properties were investigated through optical transmission. It was found that all annealed films were polycrystalline with preferential (111) orientation. The grain size increases as the annealing temperature increases. The optical transmission data showed that annealed films exhibit high transmission. The band gap and the refractive index changed with increase in annealing temperature.