Figure 4.
Read pulse endurance characteristics. (a) Read pulse endurance properties degraded at high negative voltage due to the Joule heating phenomena for the smallest size devices. The Cu pillar is broken during read endurance test, which is shown in schematic view. (b) For the large size devices, long endurance reveals the robustness of the Cu pillars inside the switching medium at a V read of -1.5 V. Long read endurance of 105 cycles is obtained for the 8-μm devices. A stronger Cu pillar is formed into the Al2O3 films, which is shown in schematic view inside of figure.