Cu2ZnSnS4 films deposited by a co-electrodeposition-annealing route

Cu2ZnSnS4 (CZTS) films were successfully prepared using a co-electrodeposition-annealing route, in which metal precursor layers were deposited by a co-electrodeposition in aqueous ionic solution, followed by the sulfurization in elemental sulfur vapor ambient at 400 °C for 30 min using nitrogen as the protective gas. The dependence of the structural and optical properties on composition in aqueous solution is investigated. It is shown that CZTS film synthesized at Cu/(Zn + Sn) = 0.71 and Zn/Sn = 1 has a kesterite structure with an absorption coefficient in the order of 104 cm− 1, and the band-gap can be feasible modified by changing the element ratios in solution. This indicates that co-electrodeposition-annealing method is a viable process for the growth of CZTS films for the application in photovoltaic device.