Impact of ion implantation on μ-RCLEDs performance for visible-light communication

This study presents a synergistic fabrication strategy aimed at addressing the scaling-induced limitations of microcavity resonant cavity light emitting diodes (μ-RCLEDs). By integrating multi-energy oxygen (O) ion implantation, SiO 2 passivation, and high-reflectivity SiO 2 /TiO 2 distributed Bragg reflectors (DBRs), we achieve simultaneous enhancements in the electrical, optical, and modulation performance of devices with diameters of 50, 25, and 10 μm. The combined implantation passivation approach effectively mitigates sidewall-induced leakage by approximately 90 % and reduces the turn-on voltage by up to 20 %, evidencing substantial defect passivation and electric-field uniformity at the microscale. Optical characterization demonstrates that DBR assisted cavity resonance significantly improves the external quantum efficiency (EQE) increases by 18 %, attributed to enhanced photon extraction and reinforced cavity resonance. The light output power (LOP) rises by 29 %, confirming improved vertical emission efficiency and superior optical confinement, respectively, while concurrently narrowing the emission linewidth and enhancing beam directionality by over 30 %. Notably, the modulation bandwidth is increased by up to 50 % in miniaturized devices, establishing a clear correlation between cavity engineering and the stringent bandwidth requirements of high-speed optical communication. These findings outline a scalable approach that enables improved performance and modulation bandwidth in μ-RCLEDs, helping to bridge the gap between device miniaturization and performance retention. The proposed methodology offers a versatile platform with broad applicability in visible-light communication (VLC), micro-display technologies, and next-generation optical interconnects. Fabrication procedure of μ-RCLEDs. • Ion implantation with SiO 2 passivation lowers turn-on voltage by ∼20 % and suppresses leakage current by 92 %. • SiO 2 /TiO 2 distributed Bragg reflectors enhance photon confinement, improving EQE and LOP by 18 % and 29 %. • DBR engineering reduces beam divergence by 28∼35 %, enabling energy-efficient optical coupling and integration. • The synergistic strategy achieves up to 50 % enhancement in modulation bandwidth for high-speed optical communication. • The optimized μ-RCLEDs overcome miniaturization-induced losses, offering scalable light sources for LiFi photonics.