Multifunctional Ultraviolet-C Micro-LED With Monolithically Integrated Photodetector for Optical Wireless Communication

In this paper, a multifunctional ultraviolet-C (UVC) micro-LED with monolithically integrated photodetector (PD) based on AlGaN multiple quantum wells (MQWs) was fabricated. We designed and integrated UVC LED with sizes of 40 and 300μm emitted at 277 nm on a single chip which also serve functions as PDs and further studied the performance of on-chip real-time photodetection. The photocurrent generated from one LED can well reflect the light output power of the adjacent LED. Furthermore, both 40μm UVC micro-LED and 300μm UVC LED play important roles in high speed UVC communication with record bandwidths of 497.58 MHz for 40μm micro-LED and 467.38 MHz for 300μm LED, offering each other as backup light source in high speed UVC communication. And the data transmission rates of 1.6 Gbps for 40μm micro-LED and 1.21 Gbps for 300μm LED over 1 m link based on the 16-ary quadrature amplitude modulation orthogonal frequency division multiplexing (16-QAM-OFDM) with pre-equalization were achieved. The multifunctional UVC micro-LED monolithically integrated PD, without the need for an external PD to monitor the fluctuations in the luminescence, providing high stability for diverse applications, such as spatial wireless communication for 6 G communication.