Close-space sulfurization of sputtered metal precursors for Cu2ZnSnS4 thin-film solar cells

Close-space sulfurization (CSS) of sputtered metal precursors is developed for the first time to fabricate Cu
₂
ZnSnS
₄
(CZTS) thin-film solar cells. To optimize the CSS parameters, a series of CZTS thin films are prepared by sulfurizing stacked metal precursors with various sulfurization temperatures and durations. These films are studied by different characterization techniques and then fabricated into solar cell devices. According to the XRD, Raman and SEM, single-phase CZTS thin films with densely packed large grains are formed after CSS. The best cell performance with an efficiency of 5.2% is achieved for the CSS at 590°C for 30 min.