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

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.