Mimicking Pain-Perceptual Sensitization and Pattern Recognition Based on Capacitance- and Conductance-Regulated Neuroplasticity in Neural Network

Abstract

Neuromorphic computing, inspired by the biological neuronal system, is a high potential approach to substantially alleviate the cost of computational latency and energy for massive data processing. Artificial synapses with regulable synaptic weights are the basis of neuromorphic computation, providing an efficient and low-power system to overcome the constraints of the von Neumann architecture. Here, we report an ITO/TaO x -based synaptic capacitor and transistor. With the drift motion of mobile-charged ions in the TaO x , the capacitance and channel conductance can be tuned to exhibit synaptic weight modulation. Robust stability in the cycle-to-cycle (C2C) variation is found in capacitance and conductance potentiation/depression weight updating of 0.9 and 1.8%, respectively. Simulation results show a higher classification accuracy of handwritten digit recognition (95%) in capacitance synapses than that in conductance synapses (84%). Besides, the synaptic capacitor consumes much less energy than the synaptic transistor. Moreover, the ITO/TaO x -based capacitor successfully emulates the pain-perceptual sensitization on top of the superior performance, indicating its promising potential in applying the capacitive neural network.

Mimicking Pain Conditioning Using an Electrolyte‐Gated Organic Synaptic Transistor

“…In spite of the difference of the spiking frequency between a biological synapse and the synaptic transistor, which results from the limitation of our pulse frequency setting, our device is still capable of simulating the high‐pass filtering function in the biological function. [ 19,22 ] And as the number and frequency of the presynaptic voltage pulses increase, this facilitation effect became stronger, which also demonstrating a typical spike‐rate‐dependent plasticity (SRDP) as in a biological synapse. In a biological synapse, a certain time period is needed for the residual neurotransmitters concentration to relax to their equilibrium state after a presynaptic spike.…”

“…[17,18] Recently, various artificial synaptic transistors (TFTs) gated by ionic gels or electrolytes have been investigated to imitate the biological synaptic and pain-perceptual behavior in the nervous system. [19][20][21][22][23] These inorganic metaloxide-based transistors exhibit excellent stability and outstanding electrical performances such as low off-current and high electron mobility. Nevertheless, the issue of lacking biocompatibility for tissue interfacing still exists, and the high-performance carrier transporting layers are often fabricated by vacuum-based process, which aggravate fabrication complexity and cost.…”

Bilayered Oxide Heterostructure‐Mediated Capacitance‐Based Neuroplasticity Modulation for Neuromorphic Classification

“…The migration of oxygen vacancies under an applied electric field is often considered the switching mechanism for oxide-based devices. [39][40][41] To examine the capacitive switching behavior, ultraviolet photoelectron spectroscopy (UPS) analysis was used to obtain the energy levels of the WO x and ZrO x layers (Figure S4, Supporting Information). The work function and valance band level were determined using cutoff level (E cutoff ) and onset energy (E onset ).…”

Enhancement of the Synaptic Performance of Phosphorus-Enriched, Electric Double-Layer, Thin-Film Transistors

“…To assess the effects of phosphorus on the EDL and synaptic behavior, undoped silicate spin-on glass (SOG)-based transistors were prepared for comparative analyses [26,27]. The electrical properties of the two types of silicate glass layers were analyzed by measuring the frequency-dependent (C-f ) capacitance curve using a metal-oxide-semiconductor (MOS) capacitor configuration [28,29]. PSG-based MOS capacitors exhibited high-capacitance values ranging from 18.666 µF/cm 2 to 0.109 µF/cm 2 in the frequency range of 1-10 7 Hz.…”