A polycrystalline Bi2(Te1-xSex)3 with variable composition x (where 0 ≤ x ≤ 1) has been prepared using Bridgman method. Thin films of the prepared alloys with different compositions were deposited onto ultra clean glass substrates by the thermal evaporation technique. The as-deposited Bi2(Te1-xSex)3thin films were investigated by electron scanning microscope (ESM), energy dispersive spectroscopy (EDAX) and X-ray diffraction (XRD) for surface morphological, compositional and structural studies. X-ray diffraction study confirmed that the bulk materials with different compositions are polycrystalline in nature having rhombohedral structure. The as-deposited films have amorphous structure but the films annealed at temperatures more than 400 K are polycrystalline. The effect of selenium content and the thermal annealing on various structural parameters was also investigated. The thin films exhibit preferential orientation along the [015] direction for the films annealed at temperatures more than 400 K, together with other abundant planes (101) and (110). Various structural parameters such as lattice constants, crystallite size, strain and density have been calculated and they are found to be compositional dependent.
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