Low Reset Current in Stacked $\hbox{AlO}_{x}/ \hbox{WO}_{x}$ Resistive Switching Memory

The complex impedance spectroscopy method associated with capacitance-voltage is employed to investigate the resistive switching behavior of the bilayer structure for the first time. The reset current is reduced by more than one order for the AlO
_x
/WO
_x
bilayer compared with that of the single-layer structure. It is distinguished that each layer plays an important role. The AlO
_x
layer is the dominating switching layer, while the WO
_x
layer has the functions of controlling the conductive filaments in the AlO
_x
layer and acting as a series impedance to reduce the reset current.