Artificial synapse network on inorganic proton conductor for neuromorphic systems

Abstract

The basic units in our brain are neurons, and each neuron has more than 1,000 synapse connections. Synapse is the basic structure for information transfer in an ever-changing manner, and short-term plasticity allows synapses to perform critical computational functions in neural circuits. Therefore, the major challenge for the hardware implementation of neuromorphic computation is to develop artificial synapse network. Here in-plane lateral-coupled oxide-based artificial synapse network coupled by proton neurotransmitters are selfassembled on glass substrates at room-temperature. A strong lateral modulation is observed due to the proton-related electrical-double-layer effect. Short-term plasticity behaviours, including paired-pulse facilitation, dynamic filtering and spatiotemporally correlated signal processing are mimicked. Such laterally coupled oxide-based protonic/electronic hybrid artificial synapse network proposed here is interesting for building future neuromorphic systems.

Nanoionics-Based Three-Terminal Synaptic Device Using Zinc Oxide

“…1 Despite these worldwide efforts, neuromorphic systems with similar levels of robustness in terms of energy efficiency, self-learning and scalability in emulating complex biological activities are yet to be realised. 2 At a cellular level, the nervous system is composed of neurons that are interconnected by synapses.…”

“…Transparent conducting oxide (TCO) based synaptic devices hold great promise in realising energy efficient synaptic operation and spike timing dependent plasticity and short-term to long-term memory transitions have been demonstrated using Indium Zinc Oxide thin film transistors with nanogranular Silicon dioxide based proton conductor films as insulators. [31][32][33] The main drawback of such synaptic devices are the requirements of humidity to function as a synaptic FET, where the proton conductivity in the phosphorus-doped nanogranular SiO2 films is facilitated by absorbed water molecules in the nanoporous film. 33,34 Short term synaptic plasticity is demonstrated with aqueous gated Indium Gallium Zinc oxide (IGZO) synaptic devices using water and salt as gate electrolyte.…”

Neuromorphic behavior in percolating nanoparticle films

“…There have been a variety of proposals for both deterministically assembled and selfassembled systems that exhibit neuromorphic behavior in some form, with some impressive results achieved [6,7,16,[18][19][20][21][22]. The considerable current excitement about neuromorphic behavior is driven at least partially by the possibility that that the collective behavior of these system will exhibit emergent behavior similar to that which occurs in the brain [23].…”

“…The first memristive devices were based on movement of impurities in semiconducting matrices [1], and the first atomic switches relied on the electrochemical reduction of Ag 2 S to form atomic scale silver wires [3]. Since then, many other related devices have been reported, including those based on, for example, polymers [15], indium zinc oxide [16], and superconductors [17].…”

Protonic/electronic hybrid oxide transistor gated by chitosan and its full-swing low voltage inverter applications

“…9,10 Recently, solid state electrolytes have also been proposed to act as gate dielectrics. 11,12 With the unique ionic/electronic hybrid behaviors, these electrolyte gated EDL transistors have been proposed for applications in pH sensors, 13 logic circuits, [14][15][16] artificial synapses, 17,18 etc.…”