The Cu2ZnSnS4 (CZTS) thin films have been electrochemically deposited from a weak acidic medium (pH 4.50~5.00) onto Mo- coated and ITO-coated glass substrate by using single-step electrodeposition method. Trisodium citrate was used as a complexing agent. The effect of annealing atmospheres such as Ar, N2, N2+H2S on the structural, morphological, compositional, and optical properties of CZTS thin films has been investigated by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and optical absorption techniques, respectively. XRD studies reveal that the as-deposited CZTS film is amorphous in nature. Upon annealing in different atmospheres, a relatively more intense and sharper diffraction peaks (112), (200), (220), and (312) of kesterite crystal structure with uniform and densely packed surface morphology are observed in N2+H2S atmosphere. Absorption study shows that the band gap energy of as-deposited CZTS thin film is 2.8 eV whereas after annealing, it is found to be 1.48, 1.76, and 1.53 eV for Ar, N2, N2+H2S atmospheres.
Effect of Annealing Atmosphere on the Properties of Electrochemically Deposited Cu2ZnSnS4 (CZTS) Thin Films