Magnetron sputtering of hybrid metal halide perovskites: barriers to scalable fabrication.

Radio frequency (RF) magnetron sputtering is a scalable, solvent-free, and industry-compatible deposition technique well-suited for roll-to-roll manufacturing. Despite its many advantages, this technique is not commonly used for the deposition of metal halide perovskites, which have emerged as one of the most promising photovoltaic materials. In this study, we systematically explore the barriers to depositing high-quality perovskite thin films from hybrid perovskite targets, which were prepared by pressing ball-milled dry perovskite powder. By investigating the influence of target stoichiometry, applied RF power, and Argon gas pressure on the structural, morphological, and compositional characteristics of the sputtered thin films, we identify key limitations to the application of magnetron sputtering to the fabrication of perovskite layers. Specifically, we reveal that the microstructure of these films exhibits a very rough surface and inadequate grain formation, limiting their use in subsequent optoelectronic applications. Additionally, target disintegration during sputtering poses a significant challenge, raising concerns about the feasibility of RF sputtering for roll-to-roll production of perovskite optoelectronic devices. Based on these insights, we discuss not only the limitations of the process but also potential paths to addressing these barriers.