Semiconductor devices having phase change memory cells, electronic systems employing the same and methods of fabricating the same

Abstract

A phase-change memory device has an oxidation barrier layer to protect against memory cell contamination or oxidation. In one embodiment, a semiconductor memory device includes a molding layer disposed over semiconductor substrate, a phase-changeable material pattern, and an oxidation barrier of electrically insulative material. The molding layer has a protrusion at its upper portion. One portion of the phase-changeable material pattern overlies the protrusion of the molding layer, and another portion of the phase-changeable material pattern extends through the protrusion. The electrically insulative material of the oxidation barrier may cover the phase-changeable material pattern and/or extend along and cover the entire area at which the protrusion of the molding layer and the portion of the phase-change material pattern disposed on the protrusion adjoin.