Effects of sputtering period on the performance of Cu2ZnSnS4 solar cells

Currently, most of investigations about CZTS focus on the sulfurization conditions, the precursor stacking orders, and effects of secondary phases on the device performance. However, very few researchers have a detailed investigation of sputtering period. In this paper, the effects of sputtering period on the performance of Cu2ZnSnS4 solar cells are discussed. The crystal structure, morphology, chemical composition and phase purity of CZTS thin films prepared by different periods were characterized by X-Ray Diffraction(XRD), scanning electron microscopy(SEM) equipped with an energy dispersive spectrometer(EDS) and Raman spectroscopy. The results show that the performances of CZTS devices prepared by multi periods were better than that of using single period. Meanwhile, complete devices were fabricated using CZTS thin film based on different sputtering periods, and 2.02% efficiency of CZTS by single period, 3.19% efficiency by double periods and 3.6% efficiency by four periods were obtained, respectively.