Effect of sputtered Cu2ZnSnS4 film thickness on dye sensitized solar cell counter electrode performance

Abstract

Cu2ZnSnS4 (CZTS) films were deposited on the fluorine doped tin oxide substrates using a two-step process. First step, the Cu/Zn/Sn precursors were coated on conductive glass using a direct-current magnetron sputtering method. Second step, Cu/Zn/Sn films were annealed at 600 °C for 1 h under a sulfur atmosphere. X-ray diffraction and Raman spectroscopy indicated kesterite Cu2ZnSnS4 formation. CZTS films were used as the counter electrodes (CEs) of dye-sensitized solar cells. The solar cell efficiency and the short circuit current density increased with increasing CZTS film thickness. The maximum solar cell efficiency based on CZTS CEs reached 6.27% at film thickness of 3.7 ± 0.8 μm, compared to a Pt based dye-sensitized solar cell of 7.52%. © 2019 The Japan Society of Applied Physics.