The Research On The Integration Of GaN Quantum Well And Waveguide Devices For Visible Light Communication

In the field of modern optical communication,the visible light communication technology,which transmits signals via visible light,is rapidly developing and playing an important role in people's life.The planar integrated photonic device for visible light communication is considered to be greatly promising and broadly applicable due to its small size,high stability and high response speed.Nitride semiconductor materials in the III-V group have excellent opto-electrical properties in the visible range.It can be used to fabricate light source devices and integrated photonic devices for the purpose of visible light communication.Duplex communication module integrates the optical source,the optical waveguide and the optical detector on one chip.This module is the most basic and common integrated circuit applied in planar visible light communition.Research about on-chip duplex communication is important for the development of integrated photonic devices on the field of visible light communication.The large size suspended waveguide and integrated waveguide devices based on nitride materials are studied in this thesis.The work is focused on a kind of monolithic photonic integrated devices which can be used in the in-planar visible light duplex communication.The work contains theoretical simulation,numerical analysis,structure design,fabrication process and opto-electrical testing.The main work includes:Using the finite difference time domain(FDTD)method and the finite element method(FEM),the structure design and optimization,transmitting analysis and modes simulation of the suspended slab waveguide device are proposed by the Full WAVE module and the FemSIM module of RSoft simulation software.The on-chip photonic integrated device is proposed and designed using the active gallium nitride on silicon substrate.This device realizes the monolithic integration of optical source,optical waveguide and optical detector.It is fabricated by the combination of nitride ICP etching,deep silicon etching and back thinning technique.The structure measurement and morphological analysis of the device are carried out by using the optical microscope,scanning electron microscope(SEM),atomic force microscopy(AFM).An integrated optical and electric testing system is taken for the on-chip photonic integrated devices.The electrical performances of the LED were analyzed by the semiconductor device analyzer.The suspended InGaN/GaN multiple quantum well structure is proved to be able to detectthe light transmitted by waveguide.The communicating performances of the integrated device were measured by the digital oscilloscope.It is proved that the device is anti-self-interfering.The research made foundation for the future development of monolithic photonic integrated devices with complicated functions.