Patent ID: 8426836

Claim:
A resistance variable nonvolatile memory device comprising: a substrate; a first electrode formed on the substrate; an interlayer insulating layer formed over the substrate and the first electrode; a memory cell hole formed in the interlayer insulating layer on the first electrode; a first resistance variable layer formed in at least a bottom portion of the memory cell hole and connected to the first electrode; a second resistance variable layer formed inside the memory cell hole and located on the first resistance variable layer; and a second electrode formed on the interlayer insulating layer to cover the second resistance variable layer; the first resistance variable layer and the second resistance variable layer respectively comprising metal oxides of the same kind; the first resistance variable layer having a higher oxygen content than the second resistance variable layer; the first resistance variable layer being formed in at least a portion of a side wall of the memory cell hole, in addition to the bottom portion of the memory cell hole; and the first resistance variable layer formed on the side wall of the memory cell hole extending in a ring shape along an inner wall of the memory cell hole in a cross-sectional view parallel to the substrate.