Patent ID: 7599217

Claim:
A memory cell device of the type including a memory material switchable between electrical property states by the application of energy, the memory cell device comprising: a first electrode having an electrode surface; a first material over the electrode surface to create a separation layer having an upper surface; the first material defining a hole bounded by a side wall within the separation layer, a bottom and a plane defined by the upper surface; a second material on the side wall; a third material on the upper surface of the separation layer; the third material defining a first downwardly and inwardly tapering void region above the plane of the upper surface; the second material having a tapering cross-sectional shape and defining a void, the void having a second downwardly and inwardly tapering void region below the plane of the upper surface; a memory material in at least a portion of the second void region and in electrical contact with the electrode surface; and a second electrode in electrical contact with the memory material; whereby energy passing between the first and second electrodes is concentrated within the memory material so to facilitate changing an electrical property state of the memory material.