Self-rectifying resistive switching device based on n-ZnO/p-NiO junction

The n-ZnO/p-NiO junctions have been fabricated by sol–gel method using Al as top electrodes and ITO as bottom electrodes for applications in resistive switching devices. Such devices exhibit homogenous and filamentary characteristics depending on the amplitude of applied bias. The two switching types show different switching polarities and transport mechanisms. Under a higher bias, the filamentary behavior is dominated by Ohmic conduction at low resistance state and trap related Poole–Frenkel conduction at high resistance state, while under a lower bias the homogenous switching exhibits diode conduction at high resistance state and space charge limited current at low resistance state. The homogenous switching shows self-rectifying effect with a good endurance. It may open up a simple route to suppress the sneak current in a p-oxide/n-oxide device while maintaining reasonable good resistive switching and self-rectifying properties.