Simulation of Laterally Coupled InGaZnO4-Based Electric-Double-Layer Transistors for Synaptic Electronics

Artificial synapse is the key element for neuromorphic systems. Recently, synaptic transistors have been proposed and investigated, but physical understanding of such synaptic devices based on ion/electron electrostatic coupling effect remains unknown. Here, laterally coupled InGaZnO₄ electric-double-layer synaptic transistors were numerically simulated. An ion drift-diffusion model is employed to describe the laterally capacitive coupling of the proton conducting electrolyte. Important synaptic behaviors, such as excitatory postsynaptic current and paired-pulse facilitation, are mimicked by the transient solution. InGaZnO₄ synaptic device exhibits an extremely low-power consumption of ~0.2 pJ/spike. Our simulation results are interesting for energy-efficient synaptic electronics and neuromorphic systems.