The present disclosure generally relates to memory devices and methods of forming the same. More particularly, the present disclosure relates to resistive random-access (ReRAM) memory devices. The present disclosure provides a memory device including a dielectric layer having an opening, sidewalls along the opening, a first electrode in the opening, a resistive layer disposed upon the first electrode, an oxygen scavenging layer disposed upon the resistive layer, and a second electrode in contact with the oxygen scavenging layer. The oxygen scavenging layer includes a material that is different from the resistive layer and partially covers the resistive layer. The first electrode is electrically linked to the second electrode by the oxygen scavenging layer and the resistive layer.