Effect of substrate temperature on structure, morphology and optical properties of Sb2Se3 thin films fabricated by chemical-molecular beam deposition method from Sb and Se precursors for solar cells

Abstract

Sb2Se3 thin films were obtained by chemical-molecular beam deposition on soda-lime glass from high purity Sb and Se precursors at 400 °C, 450 °C and 500 °C substrate temperature. Due to the precise control of the Sb/Se ratio, Sb2Se3 thin films with stoichiometric composition were obtained, which was confirmed by energy-dispersive X-ray microanalysis. The effect of substrate temperature on morphology, structure and optical properties of Sb2Se3 thin-films were studied by scanning electron microscopy, atomic force microscopy, X-ray diffraction, Raman spectroscopy and from the analysis of absorption and transmission spectra of the films. Average diameters and lengths of Sb2Se3 rods deposited at different substrate temperature were the range of 0.5–2 µm and 1–4 µm respectively which was grown at different slope and compactness to the substrate. The optical bandgap of the films was determined from the transmission and reflection spectra and 1.16, 1.21 and 1.26 eV band gap energies were observed for 500, 450 and 400 ℃ substrate temperature Sb2Se3 thin films respectively.