Optical and photoelectrical properties of Bi2S3 thin films obtained by spray pyrolysis technique

Polycrystalline films of Bi2S3 compound have been prepared, at substrate temperature of 570 K, from Bismuth chloride (BiCl3) and Thiourea (CS (NH2)2) solutions. The structural characterisation has been carried out by the X-ray diffraction analysis (XRD). Study of optical properties shows that Bi2S3 compound has an allowed indirect transition at 1.43 eV energy. The photoelectrical parameters (diffusion length and lifetime) have been determined from the study of the photoconductivity.