Optical radiation sensing properties of MnO/TeO/sub 2/ thin films

This work investigates the effects of gamma-rays on the optical properties of pure and mixed-oxide materials, namely MnO and TeO2 for their possible application as thin film optical gamma radiation sensors. The values of the optical band gap Eopt were obtained in view of the Mott and Davis theory. All samples showed a decrease in Eopt with an increase in radiation dose to a certain level, which was found to be composition dependent. Films with 100 wt.% MnO exhibited the highest sensitivity to low doses of radiation, showing a strong decline in the optical band gap value from 0.64 eV before irradiation to 0.54 eV after a dose of 1.14 mGy. It was experimentally confirmed that both the sensitivity and the working dose range of radiation sensors can be controlled by the composition of the materials used