High-resolution self-powered photodetector arrays based on vertical Au/PbI₂/ITO structures for advanced optoelectronic imaging

With the growing demand for photodetector (PD) arrays with high pixel counts, enhanced sensitivity, faster response, and simplified fabrication processes, traditional PD designs based on planar interdigital electrodes or two-device integration face limitations in speed, resolution, and manufacturing complexity, hindering their use in high-resolution imaging applications. This study presents a universal strategy for fabricating PD arrays with vertical structures using SiO_2-assisted photolithography and etching. The resulting 10\times10 self-powered PD array, composed of a simple Au/PbI_2/ITO structure, operates effectively without an external power supply. The microstructure of the patterned PbI_2 films and their photodetection properties are thoroughly characterized, showing an impressive on/off ratio of 7\times10^5 and rapid response times of 780 μs and 940 μs for rise and decay times under light irradiation. Notably, the self-powered PD array demonstrates excellent imaging capability, producing clear images under 450-nm laser irradiation at varying optical power densities. The low-complexity fabrication method, which exhibits high repeatability, can be applied to other material systems and is expected to expand the potential of PDs in advanced integrated optoelectronic systems.