Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7920307 | Journal of Physics and Chemistry of Solids | 2018 | 21 Pages |
Abstract
In this study, the thermal quenching technique was employed to prepare bulk samples of Se100-xHgx (xâ¯=â¯0, 5, 10, 15). Thin films with a thickness of â¼250â¯nm were deposited on glass substrates using the thermal evaporation technique. These films were irradiated with gamma rays at doses of 25-100â¯kGy. The elemental compositions of the as-deposited thin films were confirmed by energy dispersive X-ray analysis and Rutherford backscattering spectrometry. X-ray diffraction analysis confirmed the crystalline nature of these thin films upto the dose of 75â¯kGy. Fourier transform-infrared spectroscopy showed that the concentration of defects decreased after gamma irradiation. Microstructural analysis by field emission scanning electron microscopy indicated that the grain size increases after irradiation. Optical study based on spectrophotometry showed that the optical band gap values of these films increase after the addition of Hg whereas they decrease after gamma irradiation. We found that the absorption coefficient increases with doses up to 75â¯kGy but decreases at higher doses. These remarkable shifts in the optical band gap and absorption coefficient values are interpreted in terms of the creation and annihilation of defects, which are the main effects produced by gamma irradiation.
Related Topics
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Authors
Shabir Ahmad, Shama Islam, Mohd. Nasir, K. Asokan, M. Zulfequar,