Experimental Analysis of HfO2/X ReRAM devices by the Capacitance Measurements

The main objective of this work is to present an analysis of the switching properties in Resistive Random-Access-Memory devices through the capacitance measurements of the metal-insulator-metal structure. The analysis was carried out in two devices with different insulating layers, one composed of H-plasma-treated $\mathrm{H}\mathrm{f}\mathrm{O}_{2}$ and the other with a stoichiometric $\mathrm{H}\mathrm{f}\mathrm{O}_{2}$. The device with a higher quantity of oxygen vacancy related defects in the insulator $(\mathrm{H}\mathrm{f}\mathrm{O}_{2}\mathrm{w}/\mathrm{t}\mathrm{r}\mathrm{t})$ presents a wider spread of the capacitance with the application of a range of varying pulse widths. An increase in the capacitance from 3.904 to 3.917 pF$/\mu \mathrm{m}^{2}$ was observed for the same device when it was subjected to a 144 $\mu \mathrm{s}$ pulse width, demonstrating a conductance quantization required for the application in in-memory computing systems.