A semiconductor device includes; a lower structure, lower electrodes on the lower structure, wherein each lower electrode includes a first lower electrode and a second lower electrode on the first lower electrode and electrically connected to the first lower electrode, an upper electrode covering the lower electrodes, and a dielectric film between the lower electrodes and the upper electrode, wherein the first lower electrode includes a pillar portion and a protruding portion on the pillar portion, wherein protruding portion has a complex shape that contacts the second lower electrode.