A method for fabricating a memory device includes forming a bottom electrode over a substrate; forming an etch stop layer over and surrounding the bottom electrode; removing at least one portion of the etch stop layer to expose the bottom electrode; forming a stack layer over the bottom electrode and a remaining portion of the etch stop layer, the stack layer comprising a resistance switching layer; and etching the stack layer to form a stack over the bottom electrode, the stack comprising a resistance switching element over the bottom electrode and a top electrode over the resistance switching element, wherein the etch stop layer has a higher etch resistance to the etching than that of the resistance switching element.