High-Speed Micro-LEDs Based on Nano-Engineered InGaN Active Region Towards Chip-to-Chip Interconnections

The application of high-speed micro-scale light-emitting diode (micro-LED) technology in short-distance data transmission breaks through the limitations of traditional electrical connections. This is particularly crucial as the demand for large-capacity and high-speed communications becomes more urgent, with a high-speed micro-LED light source being a key component. In this work, the alternating growth interruption method is used to grow a 3-layer InGaN nanostructure with smaller size and higher density. This approach increases local carrier concentration and reduces differential carrier lifetime. Based on the 3-layer improved InGaN nanostructure, a blue micro-LED is designed and fabricated, achieving the output optical power exceeding 0.5 mW while the electro-electric (E-E) −3 dB bandwidth exceeding 2.6 GHz. Utilizing this high-speed micro-LED as the light source, three non-return-to-zero on-off keying (NRZ-OOK) real-time communication systems are demonstrated: single-channel transmission via free-space and quartz optical fiber, and 4-channel transmission via plastic imaging fiber, achieving data rates of 3.07, 2.60, and 12.00 Gbps, respectively. Additionally, the 4-channel system achieves bit-power loading discrete multi-tone (DMT) transmission of 15.05 Gbps.