Scaled-down phase change memory cell in recessed heater

摘要

A semiconductor structure configurable for use as a nonvolatile storage element includes a first electrode, an insulating layer formed on at least a portion of an upper surface of the first electrode, and a pillar traversing the insulating layer and being recessed relative to an upper surface of the insulating layer. The pillar includes a heater formed on at least a portion of the upper surface of the first electrode and a collar formed on sidewalls of the insulating layer proximate the heater and on at least a portion of an upper surface of the heater. The structure further includes a PCM layer formed on at least a portion of the upper surface of the insulating layer and substantially filling a volume defined by the upper surface of the heater and at least a portion of an upper surface of the collar. A second electrode is formed on at least a portion of an upper surface of the phase change material layer.