A semiconductor device includes a substrate structure comprising an active region, a first interlayer dielectric layer on the active region, and a first opening in the first interlayer dielectric layer and extending to the active region, at least one gate structure in the first opening and comprising spacers on sidewalls of the first opening, a gate dielectric layer on the active region, a metal gate on the gate dielectric layer, and a hardmask on the metal gate and having a first recess in a middle portion of its upper surface, the gate dielectric layer, the metal gate, and the hardmask being between the spacers, a second interlayer dielectric layer on the first dielectric layer and on at least a portion of the hardmask, and a second opening adjacent to the at least one gate structure in the first opening and exposing the spacers and a surface of the active region.