Scalable Fabrication Processes for Perovskite-Based Tandem Photovoltaics

Perovskite-based multijunction solar cells have made remarkable advances in power conversion efficiency over the past decade. The technology is on the doorstep of commercialization. Despite these advances, it remains an open question which fabrication technology – solution-based, vapor-based, or a combination – is best suited to deposit the perovskite absorber layer. Solution-based processes dominate at the laboratory scale, benefiting from fast optimization feedback and straightforward integration in modern research laboratories. Slot-die coating and inkjet printing are established scalable solution-based fabrication techniques that are heavily investigated concerning large-area and high throughput deposition. On the other hand, vapour phase deposition processes dominate today’s established thin-film manufacturing. This contribution will present a recently published balanced viewpoint from industry and academics on the advantages and disadvantages of solution-based and vapor-based large-area deposition processes for perovskite absorber layers.<br/><br/>The latest developments at the Karlsruhe Institute of Technology on vapor phase and solution-processed deposited of perovskite absorber layers in perovskite/Si tandem solar cells will be presented. We will report on advances in monitoring and controlling of the thin film formation for vapor phase and solution-based deposition, including sequential and hybrid deposition routes. Using photoluminescence imaging, we analyse the formation of the thin film morphology during the annealing, gas quenching or vacuum quenching step. For the hybrid route, the inorganic precursor materials are deposited by vacuum processes, while the organic materials are deposited from the solution in a second step by inkjet printing or slot die coating. Insights on the thin film formation on textured and planar silicon bottom solar cells will be shared along with the latest developments in controlling the homogeneous formation of perovskite thin films processed by the hybrid route on larger areas.<br/><br/><br/>(1) <i>Vapor Phase Deposition of Perovskite Photovoltaics: Short Track to Commercialization?</i><br/>T. Abzieher, D. More, …, and U.W. Paetzold. <i>Energy & Environmental Science 2024 (DOI: 10.1039/D3EE03273F)</i>