Figure 3
From: Conduction Mechanisms on High Retention Annealed MgO-based Resistive Switching Memory Devices

Box plots of 5 (50 cycles each) (a) Ru/MgO/Ta and (b) Ru/MgO/Cu RSM devices. Ru/MgO/Ta RSM devices exhibited a much better distribution and less variation in terms of HRS as compared to Ru/MgO/Cu RSM devices. This could be attributed to the lower diffusivity effect of Ta atoms in Ru/MgO/Ta RSM devices, resulting in a better control of filament formation/rupture.