A universal top-down approach toward thickness-controllable perovskite single-crystalline thin films

Abstract

Organic–inorganic hybrid perovskite single crystals have shown superior photophysical properties when compared with their polycrystalline film counterparts. Perovskite single crystal thin films are highly desirable for high-performance optoelectronic devices, but their growth remains a challenge, particularly for perovskite single crystal thin films with controllable thicknesses. Herein, we report a facile top-down strategy to fabricate hybrid perovskite single-crystalline film from its bulk single crystal. The film thickness can be controlled from several millimetres to 15 micrometres. Most importantly, the strategy is feasible for the fabrication of different types of hybrid perovskite single-crystalline films (such as CH₃NH₃PbI₃, CH₃NH₃PbBr₃, and CH₃NH₃PbCl₃) of arbitrary orientations. We demonstrate that vertical-structured photodetectors based on (100)-oriented CH₃NH₃PbI₃ single-crystalline thin films show obvious thickness-dependent photoelectric responses. Such a top-down approach provides a general route to the fabrication of perovskite single-crystalline thin film and may pave the way for the production of a variety of high-performance optoelectronic devices.