Influence of Sb3+ ions on photoconductive properties of chemically deposited PbS films

PbS films were obtained on glass substrates using the chemical bath deposition (CBD) method. The infra red (IR) photosensitivity increases of about 1000 times when a reducing agent (hydroxylamine hydrochloride NH2OHHCl) is added in the deposition bath. A further enhancement was tried by adding small amounts of antimony chloride (SbCl3) solution in the deposition bath. The result was just opposite. It was found that the photosensitivity decreases with increasing the Sb salt content. The changes in PbS photoconductive properties are correlated with the changes in film morphology due to the two compounds added in the bath — the reducing agent and the Sb salt.