A semiconductor device includes: a plurality of lower electrodes arranged on a substrate in a first direction, which is parallel to a main surface of the substrate, and a second direction parallel to the main surface of the substrate and perpendicular to the first direction; and a support structure pattern configured to connect the plurality of lower electrodes to each other to support the plurality of lower electrodes, on the substrate and including a plurality of open portions. The plurality of open portions have shapes extending longer in the second direction than in the first direction, and when viewed from inner sides of the plurality of open portions, the plurality of open portions are convex in the first direction and are concave in the second direction.