Wet-Etching-Boosted Charge Storage in 1D Nitride-Based Systems for Imitating Biological Synaptic Behaviors

Abstract

Nitride materials for memristors are benefited from their high response speed and high power density. The memristive effects on 1D nitride structures has not yet been elucidated. Hence, the activation of the memristive capability of nanowire (NW)-based nitride memristors using an uncomplicated fabrication as single-step anisotropic wet etching is proposed. Among nitrides, gallium nitride, a third-generation semiconductor, exhibits properties potentially suitable for neuromorphic applications. The wet etchant considerably alters the chemisorbed molecules and dangling bonds associated with the surface states of the nanowires. A device based on such NWs which exhibits low power consumption with no required compliance current and forming voltage for operation is demonstrated. It can integrate all memristive capabilities, including multiple state switching, nonvolatile bipolar memory, and Ca2+ dynamics-imitating synaptic actions. The examination of the memristive process also highlights the significance of altering surfaces in the devices, in addition to the shared principles that underlie biological and artificial synapses. The operating mode of the nitride-nanowire devices can be controlled by controlling the formation/dissolution of the oxygen-conductive path along the nanowires. Thus, the study realizes nanowire memristors based on a nitride material framework, that is promising for application in the 1D–1D system downsizing required for the bio-inspired artificial synapse.