A semiconductor device includes a lower structure, a capacitor on the lower structure, the capacitor including a first bottom electrode, which is extended in a direction perpendicular to a bottom surface of the lower structure, and a second bottom electrode, which is provided on the first bottom electrode, a bottom supporting pattern supporting the first bottom electrode, and a top supporting pattern provided on the bottom supporting pattern to support the first bottom electrode. The first bottom electrode includes a first material, and the second bottom electrode may include a second material. A work function of the second material is greater than a work function of the first material.