The semiconductor device including a device isolation layer disposed in a substrate and defining an active region, a first conductive pattern on the active region, an impurity region in the active region on a side of the first conductive pattern, a second conductive pattern on the active region between the impurity region and the first conductive pattern, a first spacer between the first conductive pattern and the second conductive pattern, and a contact plug disposed on and electrically connected to the first conductive pattern may be provided. The second conductive pattern may have a width less than a width of the contact plug.