Upscaling of Perovskite-Silicon Tandem Solar Cells

The efficiency of crystalline silicon solar cells is reaching its practical limit in R&D as well as in high-volume manufacturing. To further drive down the cost of electricity produced by photovoltaics, increasing the efficiency beyond the limit for single-junction crystalline silicon is strongly desirable. 2-terminal perovskite-silicon tandem solar cells represent an appealing option: they benefit from the installed manufacturing capacity and process maturity of the silicon bottom cell, and achieve the high efficiency potential by adding a thin-film top cell. The first lab results with efficiencies of more than 30% have recently been announced [1]. Naturally, such champion devices are initially produced on small areas of the order of 1 cm2 and to date not all of the fabrication methods used in the laboratory meet the challenge of scaling up to industrial production. In this paper we discuss recent advances in the field, with a focus on potential device designs and manufacturing processes.