Anatomy of resistive switching behavior in titanium oxide based RRAM device

Resistive random access memory (RRAM) devices based on binary transition metal oxides and the application for nonvolatile memory devices are becoming an area of extensive concern. The physical understanding of resistive switching is crucial for RRAM development. In this paper, both experiments and simulated dynamic formation and rupture processes of oxygen vacancy (VO) conductive filament (CF) channels in titanium oxide based RRAM devices are presented. Compared with the Al/TiO2.1/Al device with higher oxygen content, the Al/TiO1.6/Al device shows a lower forming voltage. However, little dependence on oxygen content in TiOx film is shown for other resistive switching parameters, including high resistance state resistance, low resistance state resistance, set voltage, and reset voltage. A numerical physics model is presented to relate the resistive switching behavior with the evolution CF channels in terms of VO morphology and I−V characteristics.