Microfabrication of Chiral 2D Metal Halide Perovskite Structures for Photonic Applications

Chiral 2D metal halide perovskites hold great promise for spintronic and photonic applications. However, such applications often require the microstructuring of active materials, which is challenging when deposited by solution‐based techniques, as these techniques usually rely on toxic solvents and deposition methods that are not suitable for large‐scale industrial applications. In this work, we introduce a dual‐source thermal evaporation process for fabricating ( R ‐4BrPEA) 2 PbI 4 ( R ‐4BrPEA: R ‐(+)‐1‐(4‐bromophenyl)ethylamine) chiral perovskite thin film. With rapid, mild temperature annealing, we obtain highly crystalline films exhibiting an anisotropy factor of 2.12 × 10 −3 , among the highest for this composition. The dry deposition method enables the microstructuring of the evaporated 2D perovskite film into a range of micropatterned structures, making it suitable for applications in photonics. Our results establish thermal evaporation of chiral perovskites as a scalable and versatile method for producing high‐quality films, thereby opening pathways toward their implementation in spintronic and photonic devices.