Characteristics of thin Sb2Se3 films obtained by the chemical molecular beam deposition method for thin-film solar cells

Abstract

Sb2Se3 films were obtained by chemical molecular beam deposition on soda-lime glass substrates. As a source material, 99.999% purity semiconductor Sb2Se3 pieces were used. Their evaporation and the substrate temperature were maintained at 830 °C÷1000 °C and 500 °C, respectively. Using scanning electron microscopy, X-ray diffraction analysis, and Raman scattering, the influence of the temperature of the source of the binary compound Sb2Se3 on the chemical composition, morphology, and structure of the synthesized films of Sb2Se3 films was studied. It is observed that the films have a crystalline (orthorhombic) structure with compactly located crystallites having the form of rods with an average size: l = 5÷10 µm (length) and d = 1÷2 µm (diameter). An analysis of the dependency functions (αhν)2 = f(hν) showed that the Sb2Se3 films obtained at temperatures Тsource=900 °C and Тsource=840 °C have direct transitions with an optical band gap Еg=1.04 eV and Еg=1.12 eV, respectively. The electrical conductivity of the films, changed within 1.03·10−5÷4.13·10−5 (Om·cm)−1 depending on the ratio of Sb/Se atomic concentration.