A semiconductor device includes a cell semiconductor pattern disposed on a semiconductor substrate. A semiconductor dummy pattern is disposed on the semiconductor substrate. The semiconductor dummy pattern is co-planar with the cell semiconductor pattern. A first circuit is disposed between the semiconductor substrate and the cell semiconductor pattern. A first interconnection structure is disposed between the semiconductor substrate and the cell semiconductor pattern. A first dummy structure is disposed between the semiconductor substrate and the cell semiconductor pattern. Part of the first dummy structure is co-planar with part of the first interconnection structure. A second dummy structure not overlapping the cell semiconductor pattern is disposed on the semiconductor substrate. Part of the second dummy structure is co-planar with part of the first interconnection structure. A conductive shielding pattern is disposed between the cell semiconductor pattern and the semiconductor substrate and above the first circuit and the first interconnection structure.