Optical and electrical properties of Bi2S3 films deposited by spray pyrolysis

Thin films of Bi2S3 were prepared by spray pyrolysis method. Optical constants, electrical and photoelectrical studies have been carried out on these films. The optical constants confirm that the Bi2S3 thin film has a direct band gap of 1.69 eV. The Hall Effect measurements indicate that the Bi2S3 thin films prepared by spray pyrolysis method are n-type in nature with a carrier concentration of 3.51 × 1017 cm− 3. An activated process with activation energy of 65 meV governs the conduction in these films. The photoconductivity measurement indicates the presence of continuously distributed localized gap states in this material.