Oxygen deficiency effect on resistive switching characteristics of copper oxide thin films

In this Letter, bilayered Cu2O/CuO thin films were grown on Nb doped SrTiO3 (Nb:STO) substrates by plasma assisted molecular beam epitaxy. The current–voltage characteristics of Pt/Cu2O/CuO/Nb:STO devices show reproducible and pronounced current–voltage hysteresis which was induced by the CuO/Nb:STO junctions. By comparing the current–voltage curves of the bilayered and single-layered CuO thin films, we attribute the prominent switching behavior to the oxygen-vacancies-mediated-carriers-trapped-detrapped process with the aid of the applied forward (reversed) bias voltage.

► We prepared Cu2O/CuO/Nb:SrTiO3 heterojunctions by MBE.
► The junctions show prominent and reproducible bipolar resistive switching effects.
► Interfacial barrier modulation by carrier trapping–detrapping induces the effect.
► Oxygen vacancies mediate the trapped–detrapped process with forward/reverse bias.