NON-VOLATILE STORAGE DEVICE AND METHOD OF MANUFACTURING THE SAME

In a non-volatile storage device, a first lower-layer metal wire, a lower plug, a variable resistance element, an upper plug, and a first upper-layer metal wire are formed in that order from below in a storage region, and a second lower-layer metal wire, a first via, a middle-layer metal wire, a second via, and a second upper-layer metal wire are formed in that order from below in a circuit region. The first and second lower-layer metal wires are formed in the same layer, and the first and second upper-layer metal wires are formed on the same layer. Relative to a substrate, the variable resistance element and the middle-layer metal wire have top faces at different heights, bottom faces at different heights, or both top faces and bottom faces at different heights.