CZTS solar cells with 5.75% efficiency using sputtered precursors

Recent research trends in thin film solar cells are moving towards finding alternatives based on earth-abundant elements. Cu(Zn, Sn)(S, Se)2 is being explored these days by the thin film photovoltaics community which contains earth abundant materials like Zn and Sn. CZTS has near optimum bandgap around 1.5 eV and a large absorption coefficient in the order of 10⁴ cm^-1. We have identified the optimum sequence for deposition of sputtered precursors has Sn/Zn/Cu. It was also observed that formation of Molybdenum sulfide layer can be controlled by optimizing the sulfurization process and hence series resistance can be minimized. Current efficiencies are around 6%.