Synthesis of Nanostructured Cu:As₂S₃ Thin Films by Chemical Bath Deposition Method and Their Physical Properties

摘要

Metal chalcogenide thin film preparation by chemical bath deposition is currently attracting considerable attention as it is relatively less expensive, simple and convenient method for large area deposition. In the present work preparation of un-doped and Cu doped As₂S₃ thin films by chemical bath deposition method is reported. The film characterization is undertaken to study structural, optical and electrical properties of As₂S₃ and Cu:As₂S₃ thin films. The structural characterization shows mixed monoclinic and hexagonal lattice due to As₂S₃ and CuS.The electrical resistivity of the As₂S₃ film decreases with doping as it introduces the impurity donor level in As₂S₃. The activation energy and optical band gap decreases from 0.26 to 0.03 eV and 3 to 2.34 eV due to doping of Cu in As₂S₃ film respectively. The thermo-emf measurement confirms the n-type conductivity.