Manufacture of metal halide perovskite devices by thermal evaporation: fundamentals, progress and prospects.

Metal halide perovskites (MHPs) have emerged as highly promising materials for optoelectronic devices - including solar cells, light-emitting diodes, photodetectors and resistive memories - owing to their simple fabrication, excellent optoelectronic properties, low cost, and compositional tunability. However, device-grade perovskite thin films are still predominantly produced by solution processing, which raises concerns regarding environmental impact, film reproducibility, and material waste. As a solvent-free, semiconductor-compatible alternative, thermal evaporation (TE) has attracted increasing attention as a means of overcoming these bottlenecks. Herein, this review introduces the fundamentals of TE, examines key deposition parameters affecting film quality, surveys applications of various TE methods in perovskite active layers and charge-transport layers, and highlights device performance in solar cells and other optoelectronic applications. Current challenges and future research directions in TE-based perovskite film fabrication are analyzed, and we believe that TE should not be viewed merely as a solvent-free substitute for solution processing, but as an independent manufacturing paradigm. Unlocking its full commercial potential requires a fundamental shift from empirical trial-and-error approaches to mastering vacuum-specific phase kinetics and defect chemistry, thereby establishing a roadmap toward industrial-scale, multi-device integration.