Patent ID: 8189372

Claim:
An integrated circuit comprising: a first electrode including an etched recessed portion having a planar bottom surface; a second electrode; a resistivity changing material filling the recessed portion and contacting the planar bottom surface, the resistivity changing material coupled to the second electrode, and the resistivity changing material having a first width at the planar bottom surface of the recessed portion between sidewalls of the recessed portion; and a dielectric material laterally surrounding and directly contacting sidewalls of the resistivity changing material, wherein the resistivity changing material has a second width between the sidewalls of the resistivity changing material laterally surrounded and directly contacted by the dielectric material, the second width greater than the first width, wherein the first electrode includes a first electrode material layer and a second electrode material layer, the recessed portion provided in the first electrode material layer and extending through the first electrode material layer, and wherein the planar bottom surface of the recessed portion is a top surface of the second electrode material layer.