(a) Al/Al2O3/Al (as-deposited)
(b) Al/Al2O3/Al (annealed)
Figure 4: Resistive switching of Al/Al2O3/Al stacked structures (using thicker Al2O3 = 20 nm) for the (a) as-deposited and (b) annealed devices in N2 at 300°C conditions. The unipolar mode for resistive switching is obtained after using μA and  mA. A large resistivity window is also observed for both samples.