RESISTANCE-VARYING ELEMENT AND PROCESS FOR PRODUCTION THEREOF

摘要

A resistance-varying element comprising: a lower electrode; a first oxide layer formed on the lower electrode and comprising MOx (wherein x represents the content ratio of O to M); a second oxide layer formed on the first oxide layer and comprising MOy (wherein y represents the content ratio of O to M); an upper electrode formed on the second oxide layer; a protective layer formed on the upper electrode and comprising a conductive material having a different chemical composition from that of the upper electrode; an interlayer insulating layer so formed as to cover the protective layer; and an upper contact plug formed in an upper contact hole that penetrates the interlayer insulating layer (wherein M represents a specific transition metal element; O represents an oxygen atom; and x and y represents positive integers that fulfill the formula y>x).