The Research Of GaN-based Light-induced Synaptic Transistor

GaN material plays a vital role in modern visible light communication because of its excellent photoelectric conversion performance,and its LED devices have the advantages of small size,low power consumption,high luminous efficiency and fast response speed.Based on the photochromic components,this paper explores the mechanism of optical signals replacing traditional electrical signals to realize the transmission of synaptic stimuli,designs and prepares high-performance thin-film LEDs based on InGaN/GaN multi-Quantum wells,and conducts research on GaN-based photoinduced brain neuron chips.Firstly,based on the dual functions of InGaN/GaN multi-quantum well diode devices in light emission and detection,a single-emitter neuron device is designed to explore the sensing ability of photoinduced brain-like devices by connecting the LED and detector through waveguide.Experiments show that the device can receive both on-chip and off-chip optical signals,and then distinguish them according to the characteristics of different signals.Secondly,using InGaN/GaN multi-quantum well diode devices with multiple transmitters,we explore the spatial-temporal correlation of the posterior synaptic terminals when multiple anterior synaptic terminals simultaneously transmit stimulus signals,and analyze the memory function of brain-like devices by space-time superposition.The experimental results show that when the three input terminals send different repetitive periodic signals,the amplitude of the received signals at the posterior end of the synapse increases significantly due to the space-time superposition,and periodic resonance occurs.This phenomenon indicates that there is spatial-temporal correlation between different prominent pre-input signals;the increase of the amplitude of postsynaptic EPSV makes the duration of the EPSV signal longer.That is,memory lasts longer.Finally,the logic calculation function of photosynaptic devices is explored.Using a multi-transmitter device,the logic implementation scheme of space-time superposition and space-time superposition is explored.The experimental results show that the photosynaptic device can not only realize simple logic functions such as "or","and",but also realize more complex multi-level logic decision,which indicates that the device has the potential to realize complex logic calculation after large-scale integration.