The key impact of incorporated Al2O3 barrier layer on W-based ReRAM switching performance

In this article, we inspected the bipolar resistive switching behavior of W-based ReRAMs, using HfO2 as switching layer. We have shown that the switching properties can be significantly enhanced by incorporating an Al2O3 layer as a barrier layer. It stabilizes the resistance states and lowers the operating current. Al2O3 acts as an oxygen scavenging blocking layer at W sides, results in the filament path constriction at the Al2O3/HfO2 interface. This leads to the more controllable reset operation and consecutively the HRS properties improvement. This allows the W/Al2O3/HfO2/Pt to switch at 10 times lower operating current of 100 mu A and 2 times higher memory window compared to the W/HfO2/Pt stacks. The LRS conduction of devices with the barrier layer is in perfect agreement with the Poole-Frenkel model.