Abstract
In this study, the influence of laser annealing on the structural, optical and electrical properties of thermally evaporated CdTe thin films has been investigated. CdTe thin films were deposited by thermal evaporation at different power. Thermally evaporated CdTe thin films were then subjected to post deposition laser annealing. The laser annealing was done by illuminating the films by pulsed laser beam with combined wavelengths of 1064nm and 532nm. Both the as-deposited and laser-annealed CdTe thin films were characterized using XRD, AFM, FESEM integrated with EDS, UV-Vis spectroscopy and Hall Effect measurement system. The as-grown and laser-annealed CdTe thin films deposited on soda lime glass showed polycrystalline nature with a mixture of zinc-blende (cubic, C) and wurtzite (hexagonal, H) phases. AFM images on the other hand showed increase in R.M.S roughness value after laser annealing. FESEM micrographs revealed the increase in grain size and the EDS results showed that the CdTe films became tellurium rich upon laser annealing. The band gap of the films increased after laser annealing due to the quantum confinement effect as revealed from optical analysis. Hall Effect measurement found different electrical nature of the CdTe thin films after laser annealing.