In a capacitor, and a method of fabricating the same, the capacitor includes a lower electrode, a dielectric layer on the lower electrode, and an upper electrode on the dielectric layer, wherein the dielectric layer includes a lower dielectric region contacting the lower electrode, an upper dielectric region contacting the upper electrode, and at least one middle dielectric region between the lower dielectric region and the upper dielectric region, the at least one middle dielectric region having a less crystalline region than both the lower dielectric region and the upper dielectric region.