On-Chip Integration Operating Under the Extraordinary Light Detection Mode of an InGaN/GaN Diode

Abstract

In this letter, we build an on-chip photonic integration system on a GaN-on-silicon platform. Using silicon removal and back wafer etching techniques, two suspended InGaN/GaN multiple-quantum-well diodes (MQWDs), which are connected by suspended waveguides, are fabricated as a transmitter and a receiver, respectively, in the on-chip photonic integration system. The 100- $\mu \text{m}$ -long, 2- $\mu \text{m}$ -high, and 3- $\mu \text{m}$ -wide suspended waveguides are adopted for light coupling and transmission between the transmitter and the receiver. When the transmitter emits light, the InGaN/GaN MQWD simultaneously exhibits an extraordinary light detection mechanism in which the light-induced electron-hole pairs are greatly increased and can be rapidly cancelled by the injection current. The on-chip photonic integration system experimentally demonstrates the significantly improved 3-dB bandwidth and data transport performances when the receiver operates under the simultaneous light emission and detection mode.