Research On Integrated Transceiver GaN Optoelectronic Integrated Chip

Active and passive devices based on III-nitride have been well developed in recent years,thanks to the breakthrough of the growth and doping technology of compound semiconductors with wide band gap in the 1990 s,such as gallium nitride light emitting diodes,gallium nitride laser diodes,gallium nitride photodetectors,HEMTs,low loss waveguides,etc.In particular,the development of blue LED and HEMT based on gallium nitride has come to the stage of commercialization.With it becoming more and more mature and diverse,the technology of gallium nitride discrete devices lays a foundation for realizing efficient,stable and scalable optoelectronic integrated chips based on gallium nitride materials.Better than silicon semiconductor materials,nitride semiconductor materials meet those needs in electronic market which require high speed,high power,small volume and good thermal stability.Therefore,the optoelectronic integrated chip based on gallium nitride material will be the best choice to make up for the deficiency of silicon-based semiconductor integrated chip in these applications.Based on this background,starting from the light-emitting mechanism of In GaN/GaN multi-quantum well diode,according to the overlapping region between the light-emitting spectrum and detection spectrum of multi-quantum well diode,the diode can detect the light emitted by the diode with the same quantum well structure as itself.It is concluded that multi-quantum well light-emitting diode can be used as both light emitter and photodetector.In this paper,two identical diodes are prepared on sapphire wafer containing In GaN/GaN multi-quantum wells as optical transmitter and optical receiver respectively,and then the homogeneous integration of transceiver integrated optoelectronic chip based on GaN is realized.The transceiver integrated optoelectronic chip has the ability of emitting light and detecting at the same time.The optical receiver can establish a spatial optical communication link with the optical transmitter when zero bias and emitting light,so as to realize the transmission of PRBS data and music signals.In addition to the two terminal optical communication,the reverse optical communication test is designed by using the mirror to verify that in addition to the emitted light transmitted laterally through the substrate and space,the receiver of the transceiver integrated optoelectronic chip can also detect the emitted light reflected by the mirror.It can be proved that the integrated transceiver optoelectronic chip can be made into a photoelectric reflective heart rate and pulse detection sensor.On this basis,a nitride biosensor which can detect heart rate and pulse is realized by integrating transceiver integrated optoelectronic chip with amplification and filter circuit.Finally,the ring integrated optoelectronic chips of blue and green light are prepared.After performance characterization,it is concluded that the pulse signal amplitude collected from the fingertip is greater than that collected from the wrist.The signal amplitude collected by green light integrated optoelectronic chip is significantly weaker than that of blue light chip.Therefore,the blue light integrated optoelectronic chip is more suitable to form a complete sensor prototype for heart rate and pulse detection.