Compositional effect on optical characteristics of solution grown (Cd_1−xSn_x)S thin films

A good deal of information regarding the synthesis and optical properties of chemically grown (Cd_1−xSn_x)S (x = 0.01–0.40) thin film has been reported. The growth of these films depends on various preparative parameters and deposition conditions. The reactant concentration, pH, deposition temperature, and rate of agitation were found to influence significantly the quality and thickness of the films. The photoconductive studies have been done with the help of rise and decay curves. Lifetime, mobility, and trap depth are calculated for observed parameters. Band gap measurements for the prepared films have been done with the help of optical transmission spectra using UV-VIS-IR spectrophotometer (190–1100 Å). Interesting results of PC rise and decay studies, optical absorption, and transmission spectra have been presented and discussed. Mobility is influenced significantly by Sn composition. The action spectra showed displacement in the absorption edge towards lower energy side by the addition of Sn mole content. The energy gap decreased from 2.1 to 1.9 eV for x = 0.01 and 1.85 eV for x = 0.02.