Investigation of the Impact of Post-Deposition Argon Plasma Treatment of Thermally Evaporated Cadmium Telluride Thin Films

Cadmium telluride exhibits unique photoelectric properties, making it suitable for use in thin-film solar cell modules. This study subjected thermally evaporated cadmium telluride thin films to post-deposition irradiation with argon plasma at various powers (20–40 W). The influence of plasma irradiation on the structure, bulk chemical composition, surface chemistry, and optical properties of the films was investigated. Additionally, the impact of plasma treatment on photocurrent and photoresponse was evaluated. Optimal performance was achieved with a 30 W plasma treatment, resulting in films with larger crystallite sizes and reduced surface roughness, a wider band gap, and increased optical absorption due to the creation of plasma-induced defects. These films exhibited relatively high electrical conductivity, resulting in a lower photoresponse.