Resistive Switching in Al/Graphene Oxide/Al Structure

We report resistive switching behaviors in an Al/graphene oxide/Al planar structure. Graphene oxide was synthesized by a modified Hummer's method from graphite rods. The planar structures were fabricated on a Si/SiO₂ substrate by spin-coating graphene oxide suspensions and patterning Al electrodes by photolithography. Both diode-like (rectifying) and resistor-like (nonrectifying) behaviors were observed in the device switching characteristics. Electrical characterization of the Al/graphene oxide interface using the induced current identified a potential barrier near the interface and its spatial modulation, caused by local changes of resistance at a bias voltage, which correlated well with the resistive switching of the whole structure. The mechanism of the observed local resistance changes near the electrode and the associated resistive switching of the entire structure is associated with the electrodiffusion of oxygen and the formation of sp² graphene clusters in an sp³ insulating graphene oxide layer formed near the electrode by a pre-forming process.