Effect of substrate temperature on properties of co-evaporated copper antimony sulfide thin films

In recent years, a wide variety of copper based chalcogenides have been investigated to address the need of sustainable photovoltaic materials. The ternary chalcostibite copper antimony sulfide (CuSbS2) is an emerging semiconductor in photovoltaics, optoelectronic devices and energy storage applications due its suitable band gap, high absorption coefficient and environment friendly nature. CuSbS2 thin films were deposited on glass substrates using the co-evaporation method at various substrate temperatures. The films are characterized by X-ray diffractometer, UV-Vis-NIR spectroscopy and Hall-effect measurement to study the impact of substrate temperature on structural, optical and electrical properties. The Photoresponse measurements were carried out for all films under the solar simulator. The composition of the films was confirmed using Energy dispersive X-ray spectroscopy analysis. The valance states of the constituent elements were found by X-ray photoelectron spectroscopy analysis. The energy band gap values of CuSbS2 films are in the range of 1.58-1.70 eV. All films are photoconductive and show p-type conductivity. The present studies confirm that CuSbS2 can be a potential absorber layer in thin film solar cells.