Marangoni Flow Reinforced Stencil Printing of Perovskite Single‐Crystal Arrays Toward Functional Optoelectronic Devices

Abstract Patterned perovskite arrays with subwavelength nanostructures have greatly accelerated the development of high‐performance and multifunctional optoelectronic devices due to the strong light‐matter interactions. However, the fabrication of perovskite subwavelength nanostructure devices suffers from polycrystalline structure, high cost, long cycle, and low throughput, which limits the application of large‐area, high‐performance, and multifunctional devices. In this study, we innovatively report a high‐throughput and universal wafer‐scale perovskite single‐crystal arrays processing method by synergy of stencil‐assisted printing technique and fluid dynamics modulation, enabling the patterning of perovskite single‐crystal arrays with subwavelength nanostructures, tunable crystal sizes, different band gaps, and substrates. Pure crystallographic orientation, accurate positioning, and high‐quality perovskite single‐crystal arrays with subwavelength nanostructures ensure the realization of a low‐threshold and directional emission laser. Furthermore, high‐performance polarized photodetectors were demonstrated based on single‐crystal arrays with subwavelength nanostructures. This pioneering work provides a new strategy and opportunity for the wafer‐scale integration of perovskite single‐crystal functional optoelectronic devices.