Study of gamma-radiation-induced optical effects in Ge-Se-Cd for possible industrial dosimetric applications

The effect of (CO)-C-60 gamma-irradiation on the optical properties of the amorphous chalcogenide semiconductor. Ge14Se71Cd15 is studied. gamma-radiation-induced darkening is observed after irradiation of the thin film samples for doses up to 500 kGy. The changes in the optical absorption coefficient have been attributed to the amorphous network rearrangements and the degree of disorder caused by the gamma-irradiation. The dosimetric characteristics of Ge14Se17Cd15 for gamma-irradiation measurements are proposed. The absorption coefficient was found to increase with the increase of dose in a nearly linear manner. The optical energy gap was found to decrease with the increasing dose. The values of the absorption coefficient in the absorption edge region are suitable control parameters of the proposed dosimeter material, which is characterized by the sensitivity and reproducibility of measurements. The proposed dosimeter material has a minimum detectable effect at a dose of 100 kGy. This makes the material a good candidate for dosimetry in high-dose industrial applications such as sterilization. (C) 2004 Published by Elsevier Ltd.