γ-Irradiation effects on the optical properties of amorphous Ge10As30Se60 thin films

Amorphous Ge10As30Se60 thin films on glass substrates were prepared by thermal evaporation method. The effect of γ-irradiation on the optical properties of the amorphous Ge10As30Se60 thin films was studied in the spectral range from 200 nm to 1100 nm. γ-Radiation-induced bleaching was observed after irradiation of the samples for doses up to 50 kGy. An increase in transmission and a shift in the (transmission) absorption edge towards higher energies were observed with the irradiation dose. An increase in the optical energy gap with irradiation dose was also observed in the studied range. Photo-bleaching due to γ-irradiation was discussed in light of the structural aspects and configurational-coordinate model for Ge-As-Se.