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.