Picosecond laser processing enabled geometrical fill factors exceeding 98 % for inverted wide bandgap perovskite solar modules

Perovskite solar cells (PSCs) have exhibited significant advancements over the last decade, positioning them as the most promising candidate for the next-generation photovoltaic technology. Recently, significant efforts have been focused on the scale-up of PSCs towards enabling their commercialization. In this study, we performed electrical simulations to elucidate the balance between electrical and geometric losses in PSMs and verified our model by fabricating opaque (PSMs) and semi-transparent wide-bandgap perovskite solar modules (ST-PSMs). We showed that a P2 width of 20–50 μm provides an optimized P2 contact resistance, resulting in high geometric fill factor (GFF) and fill factor (FF), simultaneously. PSMs with an aperture area of 4.2 cm², reaching a GFF of 98.4%, an FF of 81.5%, and a PCE of 17.78% were fabricated. To demonstrate the scalability of this approach, 16 cm² PSMs, reaching a GFF of 97.0%, an FF of 80.1%, and a PCE of 17.58% were fabricated. ST-PSMs (4 cm²) with >92.5% GFF, 81.4% FF, and 15.68% PCE were fabricated. We believe that the proposed optoelectronic model, along with its validation through the fabrication, exhibiting exceptionally high GFFs and FFs, elucidates the optical-electrical trade-off in PSMs and thus offers valuable insights for the design of highly efficient PSMs.