Design and Optimization of Epitaxial and Chip Structures in AlGaN-Based Deep-Ultraviolet LEDs: Toward Enhanced Efficiency and Reliability

Abstract AlGaN-based deep-ultraviolet light-emitting diodes (DUV LEDs) demonstrate significant application potential and a broad market prospect in fields such as sterilization, disinfection, optical communication, sensing, agriculture, and food processing. These devices offer distinct advantages, including eco-friendliness, nontoxicity, low energy consumption, and tunable emission wavelengths. Over the past two decades, sustained research and development efforts have led to considerable improvements in luminous efficiency and device lifetime, advancing AlGaN-based DUV LEDs toward commercialization. Nevertheless, their overall performance still lags behind that of fully commercialized GaN-based blue LEDs, indicating ample room for further enhancement. This review begins with an overview of the current development status of AlGaN-based DUV LEDs and examines key methodologies for improving device performance. It then systematically summarizes recent research advances and optimization strategies, focusing on two critical areas: material epitaxial growth and chip structural design. Finally, it discusses current technical challenges and outlines future development opportunities in the field.