Patent ID: 8343798

Claim:
A method of fabricating a phase change semiconductor memory device, the method comprising: forming a first electrode in an insulation layer formed on a semiconductor substrate; forming a first interlayer dielectric layer on the insulation layer including the first electrode; forming a first via hole through the first interlayer dielectric layer to expose the first electrode; forming a first phase change material layer on the first interlayer dielectric layer to at least partially fill the first via hole; etching the first phase change material layer using a plasma formed from a plasma gas having a molecular weight of 17 or less to form a first phase change material pattern in the first via hole; and before etching the first phase change material layer using the plasma, etching the first phase change material layer using a dry etching process or a chemical mechanical polishing (CMP) process to remove a portion of the first phase change material layer outside of the first via hole.