US Patent 7910912 Semiconductor devices having a planarized insulating layer

A semiconductor device includes at least one phase-change pattern disposed on a semiconductor substrate. A planarized capping layer, a planarized protecting layer, and a planarized insulating layer are sequentially stacked to surround sidewalls of the at least one phase-change pattern. An interconnection layer pattern is disposed on the planarized capping layer, the planarized protecting layer, and the planarized insulating layer. The interconnection layer pattern is in contact with the phase-change pattern.