Patent ID: 7687310

Claim:
A method for manufacturing a phase change memory device, comprising the steps of: forming a first insulation layer on a semiconductor substrate, the first insulation layer having an opening; forming a lower electrode in the opening; forming a sacrificial layer and a hard mask layer on the lower electrode; performing a first etching using a first etching process on the hard mask layer and the sacrificial layer to form a first stack pattern on the lower electrode, the first stack pattern having a first width less than a width of the lower electrode, wherein the first etching process is performed using a photoresist pattern; performing a second etching using a second etching process on the sacrificial layer and the hard mask layer of the first stack pattern to form a second stack pattern of the sacrificial layer and the hard mask layer which has a second width less than the first width, wherein the second etching process is a different etching process than the first etching process, and the second etching process is a reactive ion etching process; forming a second insulation layer on the first insulation layer to cover the second stack pattern; chemical mechanical polishing the second insulation layer to expose the sacrificial layer of the second stack pattern; removing the exposed sacrificial layer of the second stack pattern to define a contact hole in the second insulation layer; forming a lower electrode contact in the contact hole; and forming a phase change layer and an upper electrode on the second insulation layer and the lower electrode contact.