High-density WOx-based RRAM with a W-doped AlOx insertion layer

The tungsten oxide (WO_x) based RRAM device is improved by inserting a W-doped AlO_x layer through via oxidation process. Compared with Al/TiN/WO_x/W single switching layer devices, Al/W:AlO_x/WO_x/W bilayer devices have much better resistive switching performance. Temperature dependent electrical measurements show distinctively different conduction mechanisms in those two kinds of devices, which explains the switching performance improvement. In order to achieve high device density, a 1T1R RRAM structure is proposed, based on advantages of Al/W:AlO_x/WO_x/W devices. The structure shows better current compliance and narrower resistance distribution in LRS.