Excellent Switching Uniformity of Cu-Doped $\hbox{MoO}_{x}/\hbox{GdO}_{x}$ Bilayer for Nonvolatile Memory Applications

We have investigated a Cu-doped MoO x /GdO x bilayer film for nonvolatile memory applications. By adopting an ultrathin GdO x layer, we obtained excellent device characteristics such as resistance ratio of three orders of magnitude, uniform distribution of set and reset voltages, switching endurance up to 10 4 cycles, and ten years of data retention at 85degC. By adopting bilayer films of Cu-doped MoO x /GdO x , a local filament was formed by a two-step process. Improved memory characteristics can be explained by the formation of nanoscale local filament in the ultrathin GdO x layer.