Optical Properties of Thermally Evaporated Sb₂S₃Thin Films

Optical properties in Sb₂S₃thin films prepared by thermal evaporation have been investigated. The as deposited films are found to be amorphous with a high resistance in nature. An amorphous-crystalline phase transition is also observed in the subsequently annealed films at 498K in vacuum 10-3 Torr. The films shows a indirect optical energy gaps(Eop) lie in the regions of 2.04 and 1.92eV for amorphous and crystalline phases, respectively. As the results of photo-luminescence spectra analysis, the state density in the non-extended region was relatively increased by the annealing. Therefore we assume that the radiative transition was more dominant than non radiative transition in Sb₂S₃thin films.