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Monolithic perovskite/silicon tandem solar cells have the potential to reach very high power conversion efficiencies (PCEs) in a cost‐effective manner. In the last decade, significant technological advancements have been made for lab‐scale devices (~1 cm2), with PCEs now higher than the theoretical PCE limit of single‐junction silicon solar cells. For market entry of such tandems, the involved processing steps need to be scaled to industrial wafer dimensions, typically >244 cm2, which also mandates the development of adequate electrode‐metallization strategies. Here we discuss challenges and opportunities related to this, including the required properties of the front metal grid for perovskite/silicon tandems, as well as key motivations and challenges in adopting screen‐printed metallization, which is the current standard for mainstream silicon solar cells. We give a cost estimation for the front metal grid by considering the cost of low‐temperature metal pastes that are compatible with the thermal budget limitations imposed by the perovskite top cell. We also consider opportunities to employ alternative metallization schemes that arise from the reduction in current density in tandem solar cells compared to single‐junction devices. Lastly, we discuss possible routes to replace or minimize the silver content in costly silver‐based metallization for industrial applications. [ABSTRACT FROM AUTHOR]

Ultrathin solar cells can be a path forward to low‐cost photovoltaics due to their reduced material consumption and shorter required deposition times. With excellent surface passivation, such devices may feature higher open‐circuit voltages (VOC). However, their short‐circuit current density (JSC) may be reduced due to decreased light absorption. This mandates implementation of efficient light‐trapping structures. To design efficient ultrathin solar cells that combine surface‐passivation and light‐trapping features, accurate 3‐D modeling is necessary. To this end, a novel 3‐D optoelectrical finite‐element model is developed to analyze the performance of ultrathin solar cells. The model is applied to the case of ultrathin (<500 nm) chalcogenide solar cells (copper indium gallium (di) selenide, CIGSe), rear‐passivated with nanostructured Al2O3 to circumvent optical and electrical losses. It is found that such a nanopatterned dielectric passivation scheme enhances broadband light‐trapping with reduced rear‐surface recombination, resulting in an absolute power conversion efficiency enhancement of 3.9%, compared to cells without passivation structure. Overall, the work shows how 3‐D finite element modeling can aid in analyzing and developing new optical and electrical solar cell designs for ultrathin solar cells such as those based on chalcogenides and perovskites. [ABSTRACT FROM AUTHOR]