The quaternary chalcogenide material Cu2ZnSnS4 (CZTS) has received much attention owing to its excellent photovoltaic conversion properties. We report the deposition of CZTS thin films by vacuum spray pyrolysis and explore the structural, elemental, optical and electrical properties and its use as an absorber layer in the fabrication of a cadmium free solar cell device. The thin films were deposited at various substrate temperatures ranging from 325° C to 400° C using vacuum spray pyrolysis technique. Structural analysis shows crystalline nature with a CZTS kësterite phase formed at 375 °C. FESEM analysis reveals the presence of coral reef like morphology. XPS measurements were carried out to confirm the elemental composition. Uv-vis measurments indicate that the optical band gap of the as-deposited films is 1.5 eV with a high absorption coefficient of 105cm-1, which is close to the ideal value for an absorber layer. Hall effect measurement confirms the p-type nature of the samples. A simple heterojunction is fabricated with a device structure <ITO/Al:ZnO/CZTS/Ag> using CZTS as the absorber layer and Al:ZnO as the window layer. The solar cell parameters estimated are, Voc = 0.85 V, Isc= 16.68 mA, Fill factor = 36.54 % and Efficiency, ɳ = 2.87 %.

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