Abstract: A method of fabricating a nonvolatile memory device includes; forming a first sacrificial layer pattern including a first open area that extends in a first direction on a lower dielectric layer, forming a pre-lower dielectric layer pattern including a recess that extends in the first direction using the first sacrificial layer pattern, forming a second sacrificial layer pattern including a second open area that extends in a second direction on the pre-lower dielectric layer pattern and the first sacrificial layer pattern, wherein the second open area intersects the first open area, forming a lower dielectric layer pattern including contact holes spaced apart in the recess using the first sacrificial layer pattern and second sacrificial layer pattern, wherein the contact holes extend to a bottom of the lower dielectric layer pattern, and forming a bottom electrode in the contact hole.

Abstract: Methods of forming integrated circuit devices include forming an etch stop layer on a surface of a semiconductor substrate and forming a first interlayer insulating layer on the etch stop layer. The first interlayer insulating layer is patterned to define an opening therein that exposes a first portion of the etch stop layer. This first portion of the etch stop layer is then removed to thereby expose an underlying portion of the surface of the semiconductor substrate. This removal of the etch stop layer may be performed by wet etching the first portion of the etch stop layer using a phosphoric acid solution. A semiconductor region is then selectively grown into the opening, using the exposed portion of the surface of the semiconductor substrate as an epitaxial seed layer.