A research team from the University of Science and Technology of China (USTC), led by Sun Haiding, has achieved a breakthrough in vertically integrated micro-LED technology with the development of an AlGaN-based micro-LED array, specifically designed for use in deep ultraviolet (DUV) maskless photolithography systems. This innovative device combines a highly efficient micro-LED array with a zinc oxide-based photodetector, facilitating improved optical signal transmission through a transparent sapphire substrate. The team implemented a self-stabilizing luminescence system with closed-loop feedback, ensuring consistent light output while achieving a pixel density of 564 pixels-per-inch. Their successful demonstration of DUV photolithography on silicon wafers highlights the potential applications of this technology in high-resolution imaging and future multifunctional optoelectronic systems. Moving forward, the team plans to further miniaturize the micro-LEDs and photodetectors to enhance integration density and performance.