A Photolithography-Free Fabrication Strategy for Perovskite Photodetector Array with High-Security Imaging Application.

Metal halide perovskites have attracted significant attention for high-performance and cost-effective photodetector (PD) arrays in recent years. Traditional perovskite photodetector arrays typically rely on planar structure and photolithography, which limit resolution and involve complex, costly processes. To address these challenges, an innovative, lithography-free fabrication strategy is proposed utilizing direct laser writing ablation and a surface energy-assisted selective growth process. A 10 × 10 self-powered perovskite photodetector array is demonstrated with a vertical cross-bar structure fabricated on a laser-ablated textured Indium-Tin Oxide (ITO) substrate which improves the device performance. The device exhibits a fast photoresponse and effective imaging capability. Moreover, the intrinsic physical disorder and randomness of perovskite provide highly secure entropy sources, making the photodetector array suitable for physical unclonable function (PUF) devices. This method offers a promising opportunity for simplifying the fabrication process, enhancing manufacturability, and advancing the application of perovskite PD arrays in secure imaging systems.