Analysis of V th variability in NbO x -based threshold switches

Threshold switching effects in niobium oxide based filamentary resistance switching devices have attracted increasing attention due to their potential to realize scalable selector devices for ReRAM. For an application in large scale arrays the device-to-device variability is of major importance. In our work we developed a physical model describing the threshold switching effect based on a Frenkel-Poole like conduction mechanism. Based on the model we analyze the source of variability of the threshold voltage V th in the threshold switching effect of the NbO x based devices. In particular, we investigate, to which extent the inherent coexisting non-volatile memory switching effect or the thermal properties of the threshold switch are responsible for the variability of the threshold voltage.