Fabrication and Structural Characterization of Se-Ge Chalcogenide Glasses by Means of Melt Quenching Technique

The structural and optical characterization of Se-Ge alloys during melt quenching technique was the goal of this study. In this regards, five different samples of Se100-xGex (x= 10, 20, 30, 40, 50) were prepared by conventional melt quenching in quartz ampoule. The produced samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The results showed that the glass forming ability of Se70Ge30 and Se50Ge50 is so low and the structures of these alloys after quenching are combination of amorphous, GeSe2 and GeSe compounds. Although the structure of as-quenched Se90Ge10, Se80Ge20 and Se60Ge40 is fully amorphous, only Se60Ge40 shows IR transmittance (with higher 55% transmittance between 0.8-11 µm). The reflective index of this glass was in the range of 3.0 to 3.3 and decrease with increasing the wavelength. The Fermi energy, Urbach energy, indirect and direct band gaps values of Se60Ge40 glass were estimated about 0.2883, 0.1526, 1.345 and 1.28 e.V, respectively.