Cicada Wing‐Inspired Silicon Nanotower Array for MAPbI ₃ Perovskite Photodetectors with Improved Light Absorption

Abstract Methylammonium lead triiodide (MAPbI ₃ ), which stands as a prominent organic–inorganic perovskite material, has been applied in photodetectors due to its remarkable photoelectric properties. Although numerous methods have been developed to pattern perovskite films for enhanced light interaction, the fabrication of cost‐effective, periodic, and large‐scale perovskite films remains challenging. A cicada wing‐inspired silicon nanotower array, synthesized through low‐cost nanosphere lithography, enables effective patterning of MAPbI ₃ thin films via nanoimprinting. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) analyses confirm the good crystallinity of the imprinted MAPbI ₃ film. Photodetectors based on this structure demonstrate a responsivity of ≈100.1 A W ⁻¹ and a detectivity of ≈3.0 × 10 ¹³ Jones at a wavelength of 600 nm, along with significantly broadened photoresponse spanning ultraviolet (340 nm) to infrared (900 nm) regions. Finite‐difference time‐domain (FDTD) optical simulations further elucidate the enhanced light absorption mechanism in MAPbI ₃ nanotower films, suggesting great potential for photoelectronic applications.