Three-dimensional Visible Light Communication Based On Photonic Integration Chip

With the development of the Internet and wireless communication,the integration of semiconductor devices not only becomes a research hotspot in the field of optical communication,but also the basis of photonic computation and photonic communication.The integration of semiconductor devices with different functions can greatly reduce the size of the device and reduce the high power loss.Gallium nitride material(GaN)has excellent optical and electrical properties,which can realize light emission,optical transmission and optical detection.This paper faces the actual demand of visible light communication to explore the single piece homogeneous integration technology of light source,optical waveguide and photodetector.At the same time,a kind of integrated photon chip designed for visible light communication is designed and developed to further improve the practicability of visible light communication.Based on GaN materials can realize the light emitting,light transmission and optical detection at the same time,and uses the GaN monolithic homogenous integration technology,we design and manufacture a visible light communication chip integrated with light source,optical waveguide and photodetector.This integration scheme reduces the integration size of the communication chip to 300 um diameter,effectively overcoming the high complexity,high cost and difficulty of mass production.Using the technology of silicon substrate stripping and nitrogen reduction,the thickness of the optical communication chip is reduced to 3um,and the suspending devices and gallium nitride waveguide are obtained.This technique is effective to improve the light coupling efficiency,reduces the waveguide mode dispersion,reduced the thickness of the device and the junction capacitance,overcome the performance bottleneck of thick film GaN,and realizes the communication speed of 50Mbit/s successfully.Based on the mechanism's discovery of the light emission and light detection in GaN quantum well devices simultaneously,can realize a full duplex communication with same time and same frequency based on a pair of quantum well devices.At the same time,a self-interference elimination algorithm is designed to realize the extraction and separation of full-duplex communication signals in a single device,so that a single device can simultaneously emit light and detect light.In addition,based on this pair of quantum well devices,this paper also builds a three-dimensional visible light communication and testing system.