Dry Vacuum Processing of Perovskite Films: Insights Into Growth and Precision Control Enabling Batch‐Stable High‐Efficiency Solar Cells

ABSTRACT Perovskite solar cells have entered intense global competition for commercialization, yet most research heavily relies on solution processing, whereas dry vacuum processes are favored by industry owing to their successful track record in thin‐film device manufacturing. This gap reflects the perception that perovskite vacuum growth is difficult to control and intrinsically less efficient. Here, we bridge this gap by reporting a standardized dry vacuum sublimation strategy that utilizes a simple thickness sensor with fully in situ recorded log data during the vacuum deposition process. This enables rigorous comparison of two representative routes, sequential deposition and co‐deposition, and provides a basis for presenting the growth mechanism of vacuum‐sublimated perovskite films. The perovskite absorbers are fabricated without additives in the bulk, which simplifies processing. Compositional screening shows that sequential deposition yields more compact structures and enhanced optoelectronic quality relative to co‐deposition. Devices incorporating the optimized sequential films deliver a champion power conversion efficiency of 25.4%. Crucially, the process demonstrates exceptional reproducibility, with a standard deviation of 0.36% across 90 cells from eight independent runs. These results establish vacuum processing as a competitive route for industrial manufacturing and are expected to accelerate its adoption in laboratory research.