Effect of gamma irradiation on structure and photoconductivity of amorphous Sb30Se70 chalcogenide films

Abstract

The development of new materials and their processing have recently got increased attention for improving the device efficiencies for next generation solar cells. This investigation reports the effect of gamma radiation on structure-property relationship for thermally evaporated amorphous Sb30Se70 films. Amorphous/crystalline nature and molecular structure was examined by X-ray diffraction and Raman spectroscopic techniques respectively. The growth of Se crystallites in amorphous network accompanied with variation of characteristic Raman bands for Sb-Se (187 cm−1) and Se–Se (252 cm−1) vibrations have been observed. Optical gap and tailing parameter exhibit an inverse relation with γ-doses. Photoconductivity measurements revels the enhancement in photosensitivity (~27%) at 50 kGy dose and then decreases with further increase in radiation dose. The photocurrent decay data has been fitted to stretched exponential function and related parameters are reported. These results are very vital for developing new materials or processes for improving the efficiency of photovoltaic devices.