Optical characterization of aluminum doped Cadmium selenide thin film irradiated by IR-laser

Abstract

The optical properties of a cadmium selenide (CdSe) film doped with aluminum (Al) at a rate of (3%) have been studied. It was deposited on glass substrates at 250 K with a thickness of 0.15 µm and a deposition rate of 2± 0.1 m.sec-1 using a thermal evaporation technique to create the compound. The optical characteristics of the produced film were investigated after being subjected to irradiation by 50 mW, 1064 nm IR laser for 15 minutes at a distance of 0.5 m. Through monitoring the absorbance and transmission spectra of prepared thin film across the wavelength range (190-1100 nm), the optical energy gap value for the permitted direct electronic transitions was determined, and the absorption and reflectivity coefficients were computed and investigated. The optical experiments included computing the optical constants, and result explained that the optical energy gap decreased from (1.76 eV) to (1.64 eV) following irradiation (extinction coefficient, refractive index, and absorption coefficient).