High-Speed Parallel Micro-LED Arrays on Si Substrates Based on Via-Holes Structure for Visible Light Communication

In this work, the parallel micro-light-emitting diode ( $\mu $ LED) arrays based on via-holes structure with various array numbers from $1\times 1$ to $6\times 6$ are proposed. The photoelectric characteristics and frequency response characteristics of the $\mu $ LED arrays under different array numbers are analyzed. The experiment and analysis results show that the −3 dB bandwidth of parallel $\mu $ LED arrays based on via-holes structure improves as the number of arrays increases, and this result is attributed to the decrease in device RC time constant. However, the maximum withstand current density of $\mu $ LED arrays decreases as the number of arrays increases, and the $1\times 1\,\,\mu $ LED array achieves an extremely high withstand current density of 15.82 kA/cm². Among all the arrays, the $3\times 3\,\,\mu $ LED array can reach the highest −3 dB bandwidth of 606 MHz at 7.91 kA/cm² under the combined effect of withstand current density and array numbers. Meanwhile, the light output power for $3\times 3\,\,\mu $ LED array is above 15.0 mW. This work sheds light on preparation of high-performance LEDs for visible light communication.