Structural and optical studies of Sb₂S₃ films deposited by electron beam evaporation with post-annealing treatment

Antimony sesquisulfide (Sb₂S₃) has emerged as a prospective and attractive material for next-generation solar cells due to its success in solution processing, high stability, low toxicity, and exceptional optoelectronic properties. Exploring the growth properties of Sb₂S₃ films is imperative to further improve the power conversion efficiency (PCE). In this investigation, Sb₂S₃ films were effectively produced through the application of electron beam evaporation, which was subsequently followed by post-annealing treatment. The impact of annealing temperature, duration, and target weight on crystalline orientation, morphology, internal stress, and optical characteristics were examined. The films exhibited a pure orthogonal phase with strong [hk0] crystalline orientation, uniform surface, and large grains after the annealing process. The Raman spectrum analysis demonstrated that sulfur loss in films escalates with increasing annealing temperature and time. The stress in the (hk1) and (hk0) planes increases with the increase of film thickness, and the stress in the former is greater than that of the latter. The synergistic effects of the electron beam evaporation technique and subsequent post-annealing treatment further illustrate the promising potential of Sb₂S₃ for use in solar cells.