A semiconductor device includes a substrate having a plurality of active patterns. A plurality of gate electrodes intersects the plurality of active patterns. An active contact is electrically connected to the active patterns. A plurality of vias includes a first regular via and a first dummy via. A plurality of interconnection lines is disposed on the vias. The plurality of interconnection lines includes a first interconnection line disposed on both the first regular via and the first dummy via. The first interconnection line is electrically connected to the active contact through the first regular via. Each of the vias includes a via body portion and a via barrier portion covering a bottom surface and sidewalls of the via body portion. Each of the interconnection lines includes an interconnection line body portion and an interconnection line barrier portion covering a bottom surface and sidewalls of the interconnection line body portion.