Aerosol-Jet-Assisted Thin-Film Growth of CH3NH3PbI3 Perovskites-A Means to Achieve High Quality, Defect-Free Films for Efficient Solar Cells

A high level of automation is desirable to facilitate the lab-to-fab process transfer of the emerging perovskite-based solar technology. Here, an automated aerosol-jet printing technique is introduced for precisely controlling the thin-film perovskite growth in a planar heterojunction p-i-n solar cell device structure. The roles of some of the user defined parameters from a computer-aided design file are studied for the reproducible fabrication of pure CH3NH3PbI3 thin films under near ambient conditions. Preliminary power conversion efficiencies up to 15.4% are achieved when such films are incorporated in a poly(3,4-ethylenedioxythiophene): polystyrene sulfonate-perovskite-phenyl-C71-butyric acid methyl ester type device format. It is further shown that the deposition of atomized materials in the form of a gase-ous mist helps to form a highly uniform and PbI2 residue-free CH3NH3PbI3 film and offers advantages over the conventional two-step solution approach by avoiding the detrimental solid-liquid interface induced perovskite crystallization. Ultimately, by integrating full 3D motion control, the fabrication of perovskite layers directly on a 3D curved surface becomes possible. This work suggests that 3D automation with aerosol-jet printing, once fully optimized, could form a universal platform for the lab-to-fab process transfer of solution-based perovskite photovoltaics and steer development of new design strategies for numerous embedded structural power applications.