Metal halide perovskite-based solar cells have transitioned over the past decade from a research innovation to a commercially viable technology. Vapor phase deposition methods for perovskite solar cells (PSCs) are gaining increasing interest in both academia and industry, holding great promise for the commercialization of perovskite-based photovoltaics. Despite these advances, current laboratory-scale vapor-based processes are limited by low deposition rates, creating a significant barrier to achieving the production throughput necessary for industrial adoption. In this contribution, we report on the latest developments and investigations by the team at the Karlsruhe Institute of Technology on advancing vapor phase deposition processes for perovskite photovoltaics. Our research aims to provide practical guidelines to support the transition from research-scale methods to scalable and cost-effective manufacturing.

In 2024, we presented a perspective that conveys a balanced viewpoint from both industry and academia on the prospects of vapor phase deposition of perovskite photovoltaics as part of a large global consortium [1]. Building on this perspective, earlier this year we reported on strategies for achieving high-throughput vapor deposition processes for the industrialization of PSC fabrication in collaboration with industry partners [2]. The latter study addresses the critical challenges of scaling vapor-based processes by evaluating the thermal stability of perovskite precursors, analyzing deposition modes, and conceptualizing a linear sublimation source for production throughput analysis. Together, these studies offer a comprehensive framework for advancing vapor phase deposition methods and accelerating the commercialization of perovskite-based photovoltaic technologies.

Furthermore, this contribution will report on the latest developments of our team on vapor-based perovskite absorber layers and their application in perovskite single junction solar cells as well as perovskite/Si tandem solar cells. This encompasses our recent study on sequential evaporation of inverted formamidinium lead triiodide (FAPI) PSCs that highlights the impact of different hole transport layers (HTLs) on the crystallization and film formation of FAPI perovskite thin films [3]. This study reveals significant changes in PbI₂ crystal orientation depending on the HTL, which in turn affects the subsequent conversion and crystallization processes. We achieve power conversion efficiencies (PCEs) of more than 17%, the highest reported for fully vacuum-processed pure FAPI PSCs in the p-i-n architecture.

1. Abzieher, T. et al. Vapor phase deposition of perovskite photovoltaics: short track to commercialization? Energy Environ. Sci. (2024) doi:10.1039/D3EE03273F.

2. Petry, J. et al. Industrialization of perovskite solar cell fabrication: strategies to achieve high-throughput vapor deposition processes. EES Sol. 1, 404–418 (2025).

3. Diercks, A. et al. Sequential Evaporation of Inverted FAPbI3 Perovskite Solar Cells - Impact of Substrate on Crystallization and Film Formation. ACS Energy Lett. 1165–1173 (2025) doi:10.1021/acsenergylett.4c03315.