A spiking neuron circuit based on a carbon nanotube transistor

Abstract

A spiking neuron circuit based on a carbon nanotube (CNT) transistor is presented in this paper. The spiking neuron circuit has a crossbar architecture in which the transistor gates are connected to its row electrodes and the transistor sources are connected to its column electrodes. An electrochemical cell is incorporated in the gate of the transistor by sandwiching a hydrogen-doped poly(ethylene glycol)methyl ether (PEG) electrolyte between the CNT channel and the top gate electrode. An input spike applied to the gate triggers a dynamic drift of the hydrogen ions in the PEG electrolyte, resulting in a post-synaptic current (PSC) through the CNT channel. Spikes input into the rows trigger PSCs through multiple CNT transistors, and PSCs cumulate in the columns and integrate into a 'soma' circuit to trigger output spikes based on an integrate-and-fire mechanism. The spiking neuron circuit can potentially emulate biological neuron networks and their intelligent functions.

Recent Advances in Applications of Sorted Single‐Walled Carbon Nanotubes

“…However, the high energy consumption, device‐to‐device and cycle‐to‐cycle variability, complexity and scalability are yet to be addressed . In this regard, SWCNTs have emerged as an excellent candidate in the field of neuromorphic applications . Recently, sorted SWCNTs have also been considered .…”

Doping Modulated Carbon Nanotube Synapstors for a Spike Neuromorphic Module

“…Silicon (Si)‐based circuits have been utilized to emulate neural networks, but the Si circuits consumed considerably more energy than a biological network and were unable to be integrated at a scale comparable with the biological neural network . There have been extensive attempts to emulate the functions of synapses and neurons utilizing various electronic devices, such as floating gate silicon transistors, nanoparticle organic transistors, resistive switches, memristors, phase change memory, and carbon nanotube (CNT) transistors . However, the devices lack the analog memory, plasticity, or the function for spikes to trigger PSCs for spike signal processing .…”

“…Large‐scale devices and circuits have been fabricated using CNT networks and conventional lithographic techniques . Previously we have fabricated transistors based on CNT networks to emulate synaptic functions . However, it is known that CNTs have energy band gaps that vary from zero to ∼1 eV, the semiconducting CNTs became p‐type after absorbing oxygen, and no significant Schottky barrier is established between the p‐type CNT channel and its metal contacts .…”

“…However, it is known that CNTs have energy band gaps that vary from zero to ∼1 eV, the semiconducting CNTs became p‐type after absorbing oxygen, and no significant Schottky barrier is established between the p‐type CNT channel and its metal contacts . The synaptic transistors made from such p‐type CNTs have large baseline currents through the CNT channel at their idle state (with no gate bias), large power consumption, and poor plasticity and long‐term memory . In this work, we report a CNT‐based electronic device, called a “synapstor,” to emulate a biological synapse with spike signal processing, plasticity, and memory functions.…”

Excitatory Post-Synaptic Potential Mimicked in Indium-Zinc-Oxide Synaptic Transistors Gated by Methyl Cellulose Solid Electrolyte

“…For example, an essential synaptic plasticity known as spike-timing-dependent plasticity was realized by programming the timing of a pair of pre- and post-synaptic spikes in MEH-PPV polymer electrolyte-gated synaptic transistors 7. Massively parallel signal processing was emulated in carbon nanotube (CNT) synaptic transistors 8910. In these synaptic transistors, ion/electron dynamic interactions observed at the electrolyte/semiconductor interface, are of great significance to the synaptic emulations.…”