Spray pyrolysis deposition of Cu₃BiS₃ thin films

Wittichenite Cu₃BiS₃ semiconductor thin films were deposited on glass slides within a range in substrate temperature from 250 °C to 400 °C via spray pyrolysis approach. Effects of substrate temperature on crystal structure, surface morphology, and optical property of Cu₃BiS₃ films were investigated in details. Pictures from a scanning electron microscope revealed that the as-prepared films in polycrystalline nature were uniform and comprised of close-packed fine nanoparticles, which grew up greatly by increasing substrate temperature to 350 °C. The as-prepared Cu₃BiS₃ film exhibited a direct optical band gap between 1.65 eV and 1.72 eV. - Highlights: • Depositing wittichenite Cu₃BiS₃ thin films via spray pyrolysis • Polycrystalline Cu₃BiS₃ films were comprised of densely packed nanoparticles. • Direct optical band gaps of the films lie between 1.65 eV and 1.72 eV