Determination of Optical Constants of Annealed Sn doped CdSe Thin Films Prepared by Thermal Evaporation Technique

Thin films of CdSe doped with 1 at. wt.% tin are prepared by thermal vacuum evaporation technique on glass substrates at room temperature. The prepared film is annealed in vacuum at 130°C, and characterized by the transmission spectra. The transmission spectra are recorded in the transmission range 400–3300 nm. Transmittance measurements are used to calculate the refractive index (n) and absorption coefficient (α) using Swanepoel's method. The optical constants such as extinction coefficient (k), real (ε₁) and imaginary (ε₂) dielectric constants, dissipation loss (tan δ), optical conductivity (σ_opt) are also calculated for Sn doped CdSe thin films.