Patent ID: 8071970

Claim:
A phase change memory device, comprising: an electrode extending longitudinally along a first direction, wherein the electrode is strip-shaped; a strip-shaped phase change layer extending longitudinally along a second direction from a first end to a second end, and crossing and contacting the electrode at a cross region, and the phase change layer having a first recess neighboring a first side of the cross region and having a second recess neighboring a second side of the cross region, wherein the first recess extends along the second direction from the first end of the strip-shaped phase change layer to the cross region and the second recess extends along the second direction from the cross region to the second end of the strip-shaped phase change layer such that the first recess and second recess are formed in a cross-sectional profile of the phase change layer taken in a plane parallel to the second direction, and the first recess and the second recess are arranged such that a confined structure of the phase change layer is formed, and a bottom surface of the confined structure directly contacts the electrode; and a transistor comprising a source and a drain, wherein the drain or source of the transistor electrically connects the electrode or the phase change layer.