The Research Of Si-based Near-ultraviolet Photonic Chip

GaN material has become a hotspot in current research due to its excellent properties.GaN has the advantages of high band gap,high breakdown voltage,and radiation resistance.It is used to manufacture high-power devices with high temperature resistance,high voltage resistance,radiation resistance and high frequency.The high-performance RF devices made of GaN materials will become the core components in the establishment of 5G base stations in the near future.The research on GaN-based blue LEDs has been very mature,and LEDs in other light-emitting bands have gradually become a focus research.UV LEDs have attracted much attention due to their advantages such as low power consumption,small size,sterilization,and high communication security.In this paper,the epitaxial structure of UV multiple quantum well LED is analyzed by transmission electron microscope,and the problems of epitaxial growth and low internal quantum efficiency existing in the research of UV LED are discussed.The fabrication technology of near ultraviolet multiple quantum well LED devices is studied.The photolithography,etching,coating and annealing processes are introduced respectively.The methods of etching P and N steps on epitaxial wafer and the process of forming ohmic contact by evaporation of metal film on P and N steps are discussed.Scanning electron microscope was used to characterize the morphology of the prepared near ultraviolet photon integrated chip.The photon chip is integrated with optical receiver,suspended optical waveguide and optical transmitter on the same silicon substrate.The optical transmitter and optical receiver are two multiple quantum well diode devices with the same structure,both of which have an identical low-In-content In GaN/Al_0.10Ga_0.90N MQW structure,and are produced by the same fabrication process flow,the effect of optical waveguide on light is also discussed.The photoelectric characteristics of photon chip,such as IV characteristics,light emission spectrum and detection spectrum,are tested by Semiconductor Parameter Instrument and spectrometer.It is verified that the multiple quantum well LEDs with the same structure has two working modes of light emission and detection.At last,a full duplex audio communication system is built based on the homogeneous integrated near ultraviolet photon chip and the external circuit.The communication performance and audio signal superposition of multiple quantum well devices under different working modes are tested.