Towards a Three-Terminal Perovskite/Silicon Tandem Solar Cell with Highest Efficiency

In this contribution, we aim to progress towards a 3T perovskite/POLO²-IBC tandem cell with highest efficiency. For this purpose, we describe the design considerations for a 3T perovskite/POLO²-IBC tandem cell with respect to the choice of the top and bottom cell configurations and their interconnection. We identify pin perovskite solar cells (PSCs) with a band gap of around 1.6 eV spin-coated on a nano-textured p+/n+ poly-Si tunnel junction front side of a n-type unijunction POLO²-IBC bottom cells as a promising cell architecture. We report on the experimental progress with the pin PSCs on a nano-textured surface, POLO junctions optimized for textured and planar surfaces simultaneuously and the realization of the p+/n+ poly-Si tunnel junctions and ITO/n+ poly-Si recombination junctions. We fabricate high performance 3T POLO²-IBC bottom cells with p+/n+ poly-Si and with ITO/n+ poly-Si junctions on a nano-textured front side and find that the pseudo-J-V characteristics of both bottom cells is on par with our filtered single-junction 26.1%-efficient POLO²-IBC cells. Currently, we intergrate the pin PSC on the nano-textured bottom cell' font side and we will present 3T Pk/POLO²-IBC tandem cells at the conference.