Optical properties of as-prepared and irradiated In-Cd-Se thin films

Non-crystalline In3Cd3Se94 thin films were papered by the thermal evaporation technique on glass substrates. The prepared films of a-In3Cd3Se94 were irradiated by Co-60 gamma-rays at different doses (100-400 kGy). The photoluminescence study confirms that the defect concentration decreases after gamma irradiation which supports the variations in the optical parameters. The optical properties of the as-prepared and exposed to gamma-rays In3Cd3Se94 thin films have been obtained using the UV-spectrophotometer over 0.5-2.5 mu m spectral range. With the increase of gamma-doses, the index of refraction (n) was increased, whereas the optical band gap (E-g) was decreased. The estimated values of the oscillator strength E-d, static index of refraction n(o), and zero frequency dielectric constant epsilon(o) are increased with an increase of the gamma-doses while the value of the oscillator energy E-o is reduced. The absorption coefficient was discovered to rise as the gamma doses were increased. The decrease in the optical energy gap of In3Cd3Se94 chalcogenide films with the gamma-doses can be attributed to the rise in the defects after irradiation. The gamma irradiation caused a rise in the absorption coefficient as well as a change in the optical characteristics, which may be used for industrial dosimetry.