Metric for Quantifying Switching Variability in Resistive Switching Devices

Resistive switching or resistive RAM devices typically have large variability in cycle-to-cycle and device-to-device switching. It is a major aspect of ongoing research to address this device reproducibility, but there has so far been a lack of consensus to quantify this performance. We introduce a quantitative measure, which can be easily extracted from a cumulative distribution function (CDF) plot commonly used to illustrate device variability. We show how this measure remains constant with regard to the scale of the device, the measurement voltage used, whether the device is ohmic or non-linear, and regardless whether this measure is extracted from the CDF for the device resistances or currents. This will allow future studies on device variabilities to be better quantified and will also enable meta-analysis of results already published in the literature to be conducted with a potential systematic review.