Phase-change random access memory device and method of manufacturing the same

A method of manufacturing a phase-change random access memory (PRAM) device, the method comprising:

• providing a semiconductor substrate including a heating electrode;
• forming an interlayer insulating layer on the semiconductor substrate;
• etching the interlayer insulating layer, thereby forming a preliminary phase-change region exposing the heating electrode;
• burying an oxide layer in a lower portion of the preliminary phase-change region to expose a portion of a sidewall of the preliminary phase-change region;
• forming a spacer on the exposed portion of the sidewall of the preliminary phase-change region;
• selectively removing the oxide layer;
• forming a nitride layer in the preliminary phase-change region;
• etching back the spacer and the nitride layer until the spacer is entirely removed.

A phase-change random access memory (PRAM) device comprising:

• a heating electrode formed on a semiconductor substrate;
• an interlayer insulating layer formed on the semiconductor substrate and including a preliminary phase-change region exposing the heating electrode;
• a nitride layer formed in the preliminary phase-change region to have a fixed height and including a key hole exposing a portion of the heating electrode;
• and
• a phase-change material layer formed to be buried in the preliminary phase-change region and the key hole.