Roles of interfacial TiO x N 1 − x layer and TiN electrode on bipolar resistive switching in TiN / TiO 2 / TiN frameworks

Reversible counter-clockwise and clockwise resistive switching in a TiN / TiO 2 / TiN structure was studied by different polarities of bias voltage. The nature of the bipolar switching phenomenon is related to the creation and annihilation of filament paths caused by redox reactions at locally confined interfaces between the TiO 2 layer and TiN electrode. The analysis of electron energy loss spectroscopy (EELS) confirmed the formation of interfacial TiO x N 1 − x layer between the TiO 2 and TiN bottom electrode. The TiO x N 1 − x layer reduces current levels of ON and OFF states by partially blocking oxygen ion drift to the TiN bottom electrode.