Near-ultraviolet resonant-cavity light-emitting diode grown on Si

Abstract

Near-ultraviolet (NUV) light sources offer a range of notable advantages in industrial, scientific, and medical fields. In this study, we successfully fabricated AlGaN-based NUV resonant-cavity light-emitting diodes (RCLEDs) directly grown on Si substrates and designed for operation at 369.5 nm. A nanoporous AlGaN distributed Bragg reflector (DBR) was successfully fabricated by electrochemical etching as the bottom reflector, demonstrating a central wavelength of 370 nm and a peak reflectance as high as 99%. The influence of the resonant cavity effect on device performance was investigated by varying the number of the deposited dielectric DBR pairs as the top reflector. Under electrical injection, the device with seven pairs of SiO2/Ta2O5 dielectric DBR demonstrated single-longitudinal-mode emission at a peak wavelength of 369.8 nm, with a full width at half maximum of approximately 1.8 nm, exhibiting exceptionally high spectral purity. The NUV RCLED developed in this study provides valuable insights for the development and application of next-generation NUV light sources.