Localization of Filaments in Resistive Switching Devices by Ion Irradiation*

Resistive switching (RS) in transition metal oxides could find applications in a wide range of electronic devices, from conventional binary memories to artificial neurons and synapses for hardware-level neuromorphic computing. Often, the RS occurs by the formation of low-resistance filaments that percolate between the device electrodes. Because the filaments appear at different locations and follow different paths in different devices, the device-to-device variability could be very large. This presents a serious challenge for building large-scale RS circuits. In this talk, we introduce a novel approach of using focused ion beam irradiation to “guide” the filament formation. We use the RS in vanadium oxides as a case study. We show that both the position and the shape of the filament could be controllably adjusted by a relatively low dose of Ga⁺ ion irradiation. Our work demonstrates that local irradiation is an efficient tool for fine-tuning the RS properties, which could provide a general solution in solving the device-to-device variability problem.