Design of AlInGaN Electron Blocking Layer of Micro-LED Arrays Grown on Si Substrates for High-Speed Visible Light Communication

GaN-based light-emitting diodes (LEDs), which are regarded as one of the most important alternative light sources for visible light communication (VLC) systems, have been constrained by limited bandwidth. In this work, a vertically structured micro-LED array with trapezoidal AlInGaN electron blocking layer (EBL) has been proposed. This design weakens the blocking effect of charge carrier leakage through the EBL structure, improves the non-radiative recombination efficiency, significantly shortens the carrier lifetime, and thus enhances the -3 dB bandwidth. The as-prepared micro-LED arrays exhibit a light output power of 24.4 mW and a -3 dB bandwidth of 643 MHz with a transmission rate that can reach up to 4.2 Gb/s. The proper design of the EBL structure will expedite the implementation of GaN-based LEDs in the VLC system.