Abstract :
Optical, electrical and structural properties of metal oxide thin films of tellurium dioxide (TeO2), indium oxide (In2O3) and silicon monoxide (SiO) and their mixtures were studied in terms of gamma radiation influence. These films were prepared using the thermal vacuum evaporation technique. 60Co and 137Cs sources were used to expose the samples to γ-radiation. It was found that the optical band gap values decreased with increasing radiation dose. The radiation induced changes in the electrical properties of these films. Devices with resistor-type structures and p-n junctions were studied. Irradiation resulted in the degradation of the device performance, e.g. current-voltage characteristics of these devices experienced significant alterations. It was observed that values of current were increased with increasing radiation dose. The response of these devices to radiation was found to be composition-dependent. Radiation-induced changes in the structure and surface morphology of In2O3/SiO films were examined by scanning electron microscopy and X-ray diffraction. The irradiation of these thin films with a dose of 8160 μSv led to a change in their phase from amorphous to partially crystallised
Keywords :
Hall effect <thin film structs., radiation-induced changes>; X-ray diffraction <thin film structs., radiation-induced changes>; carrier mobility <thin film structs., radiation-induced changes>; crystallisation <thin film structs., radiation-induced changes>; gamma-ray effects <thin film structs., radiation-induced changes>; indium compounds <thin film structs., radiation-induced changes>; insulating thin films <thin film structs., radiation-induced changes>; optical constants <thin film structs., radiation-induced changes>; p-n junctions <thin film structs., radiation-induced changes>; scanning electron microscopy <thin film structs., radiation-induced changes>; semiconductor thin films <thin film structs., radiation-induced changes>; silicon compounds <thin film structs., radiation-induced changes>; surface morphology <thin film structs., radiation-induced changes>; tellurium compounds <thin film structs., radiation-induced changes>; thin film resistors <structs., radiation-induced changes>; ultraviolet spectra <thin film structs., radiation-induced changes>; vacuum deposited coatings <thin film structs., radiation-induced changes>; visible spectra <thin film structs., radiation-induced changes>; 0 to 36 Gy; 0 to 8160 muSv; 370 kBq; In2O3; In2O3-SiO; In2O3SiO-Si; SiO; TeO2; TeO2-In2O3; X-ray diffraction; composition-dependent response; current-voltage characteristics; device performance degradation; disc-type 137Cs radiation source; electrical properties; gamma radiation; optical band gap; optical properties; p-n junctions; partial crystallisation; radiation dose; radiation-induced changes; resistor-type structures; scanning electron microscopy; structural properties; surface morphology; thermal vacuum evaporation; thin film structures;
