Cu2ZnSn(S, Se)4 thin-film photovoltaic devices using non-vacuum based processing

Large-scale deployment of currently favored high-efficiency, thin-film photovoltaic materials (e.g., CdTe, CIGS) may be resource-limited due to dependence upon relatively non-abundant elements (e.g., In, Ga, Te). As a result, Cu₂ZnSn(S, Se)₄ (CZTSSe), with its reliance upon low-cost, earth-abundant elements, is attracting attention as an alternative candidate material for use in thin-film photovoltaic devices. In this paper, we will introduce our efforts to develop scalable routes to the low-cost, non-vacuum based construction of CZTSSe solar cells. While we have been pursuing a variety of types of precursors to CZTSSe, we will limit our results here to results derived from quaternary CZTS nanoparticles. We will focus on the processing of the CZTSSe thin films and in particular upon the effects of different annealing atmospheres. Structural and optical characterization of the resulting CZTSSe films, and the corresponding PV device performance will be presented.