Growth and characterization of tin sulphide thin films by chemical bath deposition using ethylene diamine tetra-acetic acid as the complexing agent

Tin sulphide (SnS), a promising, non-toxic and low-cost solar cell absorber layer, is grown using Chemical Bath Deposition technique at room temperature. The effects of concentration of ethlene diamine tetra-acetic acid, the complexing agent in the starting solution, as well as thioacetamide, the source of sulphur, on the growth of tin sulphide films are investigated to obtain single phase SnS films. The films deposited under optimized conditions are found to be near-stoichiometric, single phase SnS with orthorhombic structure. The lattice parameters are found to be a = 0.428 nm, b = 1.141 nm and c = 0.396 nm. The direct optical band gap of these films is found to be 1.55 eV.