Phase Transformation in Se75Te13In12 Chalcogenide Thin Films

In the present research work Se 75 Te 13 In 12 chalcogenide glass has been prepared by melt quenching technique. The non-isothermal Differential Scanning Calorimetry (DSC) measurement of synthesized alloy has been executed at constant heating rate of 25 K/min. The glass transition temperature ( T g ), crystallization temperature ( T c ) and melting temperature ( T m ) are found to be 349, 376 and 533 K, respectively. Thin films of 400 nm thickness of Se 75 Te 13 In 12 alloy were prepared by thermal evaporation technique. To study the phase transformation, the thermal annealing was done at two different temperatures 353 and 363 K for 2 h in a vacuum furnace under a vacuum of 10 –3 Torr. Optical measurements were done for as-prepared and annealed films. The optical band gap is found to decrease with increasing annealing temperature. The transformed phases of as grown and thermally annealed films were analyzed by High Resolution X-ray diffraction (HRXRD) and Field Emission Scanning Electron Microscope (FESEM).