Evidences of areal switching in Vacancy-Modulated Conductive Oxide (VMCO) memory.

In this work, we observe the switching mechanisms in non-filamentary resistive switching (RS) devices, investigated through a nanosized conductive tip used as a movable (virtual) top-electrode. The correlation between different conductive states of vacancy-modulated conductive oxide (VMCO) cells and the conductive domains in thin TiO 2 is provided. We observe the appearance of uniformly distributed conductive spots whose conductance can be reversibly modulated using a scanning biased conductive tip. Although TiO 2 has been often used as a material system for filamentary RS, these results clearly demonstrate the non-filamentary switching nature of valence change memory (VCM) cells. This supports their strong potentials in the area of applications where aggressive scaling and low-current operation is required. [ABSTRACT FROM AUTHOR]