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Article Citation - WoS: 3Citation - Scopus: 3Fabrication of Cdsexte1-X Thin Films by Sequential Growth Using Double Sources(Elsevier, 2021) Demir, M.; Gullu, H. H.; Terlemezoglu, M.; Parlak, M.CdSexTe(1-x) (CST) ternary thin films were fabricated by stacking thermally evaporated CdSe and electron beam evaporated CdTe layers. The final structure was achieved in a stoichiometric form of approximately Cd:Se:Te = 50:25:25. The post-annealing processes at 300, 400, and 450 degrees C were applied to trigger the compound formation of CST thin films. The X-ray diffraction (XRD) profiles revealed that CdTe and CdSe have major peaks at 23.9 degrees and 25.5 degrees corresponds to (111) direction in cubic zinc-blend structure. Raman modes of CdTe were observed at 140 and 168 cm(-1), while Raman modes of CdSe films were detected at 208 and 417 cm(-1). The post-annealing process was found to be an effective method in order to combine both diffraction peaks and the vibrational modes of CdTe and CdSe, consequently to form CST ternary alloy. Transmission spectroscopy analysis revealed that CST films have direct band gap value of 1.6 eV.Article Citation - WoS: 9Citation - Scopus: 9Indium Slabs Induced Structural Phase Transitions and Their Effects on the Electrical and Optical Properties of Stacked Layers of the Thermally Annealed Cu2o Thin Films(Elsevier, 2020) AlGarni, Sabah E.; Qasrawi, A. F.In this work, the effects of the structural evolutions caused by the insertion of indium slabs (100 nm) between layers of cupric oxide on the electrical and optical properties are investigated. The stacked layers of Cu2O/Cu2O (CC) which are thermally annealed at 500 degrees C in a vacuum media is observed to comprise both of the CuO (45.9%) and Cu2O (54.1%) phases in its structure. The major structural phase of CuO and Cu2O are monoclinic and orthorhombic, respectively. Insertion of indium slabs which is followed by thermal annealing reduced the content of CuO to 29.2% and enriched the content of Cu2O to 70.8%. The CC samples exhibited structural phase transitions from monoclinic CuO to hexagonal Cu2O in the presence of indium and under thermal annealing. The insertion of indium slabs in the samples increased the crystallite size and enhanced the optical transmittance. It also decreased the microstrain, the defect density and the electrical resistivity. The donor states are shifted deeper below the conduction band edge. The nature of optical transitions also changed from direct allowed to direct forbidden with a decrease in the energy band gap values from 2.05 to 0.85 eV upon indium slabs insertion followed by annealing process.
