Stateful characterization of resistive switching TiO2 with electron beam induced currents

摘要

Metal oxide resistive switches are increasingly important as possibleartificial synapses in next generation neuromorphic networks. Nevertheless,there is still no codified set of tools for studying properties of the devices.To this end, we demonstrate electron beam induced current measurements as apowerful method to monitor the development of local resistive switching in TiO2based devices. By comparing beam-energy dependent electron beam inducedcurrents with Monte Carlo simulations of the energy absorption in differentdevice layers, it is possible to deconstruct the origins of filament imageformation and relate this to both morphological changes and the state of theswitch. By clarifying the contrast mechanisms in electron beam induced currentmicroscopy it is possible to gain new insights into the scaling of theresistive switching phenomenon and observe the formation of a current leakageregion around the switching filament. Additionally, analysis of symmetricdevice structures reveals propagating polarization domains.