Dual-channel on-chip data transmission system using UV light based on GaN-on-Si wafer

Abstract

The ultraviolet photonic integrated circuits possess application prospects in ultraviolet (UV) microscopy, bio-sensing, on-chip data communication, etc. Herein, we propose a UV light on-chip data transmission system based on epitaxial GaN on silicon. This simple system includes a light-emitting diode light source, a modulator, a Y-branch waveguide and two photodetectors. Both direct modulation and indirect modulation are configured into this system and demonstrated by experiment. Dual-channel communication is also implemented through Y-branch waveguide. As all the active devices share the same InGaN/AlGaN multiple quantum wells (MQW) diode structure, this 378 nm UV light data transmission system can be monolithically integrated through the compatible manufacturing processes. By adopting the integrated MQW modulator with relatively large active region area, a significant modulation effect can be achieved with modulation depth greater than 48% under reverse bias of 20 V.