Gamma radiation-induced changes in the electrical and optical properties of tellurium dioxide thin films

摘要

Thin films of tellurium dioxide (TeO2) were investigated for Γ-radiation dosimetry purposes. Samples were fabricated using thermal evaporation technique. Thin films of TeO2 were exposed to a 60Co Γ-radiation source at a dose rate of 6 Gy/min at room temperature. Absorption spectra for TeO2 films were recorded and the values of the optical band gap and energies of the localized states for as-deposited and Γ-irradiated samples were calculated. It was found that the optical band gap values were decreased as the radiation dose was increased. Samples with electrical contacts having a planar structure showed a monotonic increase in the values of current with the increase in radiation dose up to a certain dose level. The observed changes in both the optical and the electrical properties suggest that TeO2 thin film can be considered as an effective material for room temperature real time Γ-radiation dosimetry.