The effect of soft-annealing on sputtered Cu 2 ZnSnS 4 thin-film solar cells

In this study, we investigate the effect of soft-annealing on the efficiency of Cu _2 ZnSnS _4 (CZTS) kesterite solar cells. The absorbers were grown on Mo-coated soda-lime glass by sputter deposition of Cu, SnS, and ZnS targets, and sulfurized at 585 ^∘ C for 15 min under an N _2 atmosphere. Before sulfurization, the films were subjected to a soft-annealing process in a temperature range from 150 to 350 ^∘ C. All absorbers were characterized by Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and current density–voltage ( J – V ) characteristics. The highest device efficiency of 6.1