Top Cells for Silicon-Based Tandem Photovoltaics

Tandem solar cells, which integrate multiple junctions, present a promising pathway to surpass the efficiency limits of single-junction silicon (Si) solar cells. This article explores why Si is the optimal choice for the bottom cell in tandem configurations and examines various configurations and interconnection techniques that have been reported. It then reviews a range of photovoltaic (PV) technologies for the top cell, including well-established III-V compounds and emerging materials like perovskites and chalcogenides PV materials, which are currently used or have potential for use in constructing Si-based tandem cells. Additionally, the paper highlights the ongoing challenges faced by these top cells in Si-based tandem technology. The aim of this review is to provide a comprehensive overview of different PV technological advancements and to identify strategic directions for future research that could lead to the development of highly efficient Si-based tandem PV systems.