A semiconductor device includes a substrate including first and second regions, which are arranged along a first direction. A first conductive pattern extends in the first direction in the first region. A second conductive pattern extends in the first direction in the first region. The second conductive pattern is spaced apart from the first conductive pattern. A first spacer extends between the first conductive pattern and the second conductive pattern along a sidewall of the first conductive pattern, a sidewall of the second conductive pattern, and a boundary between the first and second regions. A distance between the first conductive pattern and the second region is smaller than a distance between the second conductive pattern and the second region.