A ZnO cross-bar array resistive random access memory stacked with heterostructure diodes for eliminating the sneak current effect

We report cross-bar array resistive random access memory (RRAM) devices based on a ZnO thin film fabricated at room temperature. To prevent the sneak current path in a conventional cross-bar array device, two types of heterostructure diodes, a NiO/ZnO p-n junction and a WO3/ZnO tunnel barrier both stacked on cross-bar array RRAM were employed. With rectifying characteristics and high forward current density, the sneak current path was effectively eliminated. We believe that the proposed structures are promising for cross-bar type RRAM applications.