A capacitor includes a bottom electrode, a dielectric layer and a top electrode over a substrate. A RuXTiYOZ film is included in at least one of the bottom and top electrodes, where x, y and z are positive real numbers. A method of fabricating the capacitor through a sequential formation of a bottom electrode, a dielectric layer and a top electrode over a substrate includes forming a RuXTiYOZ film during a formation of at least one of the bottom electrode and top electrode, where x, y and z are positive real numbers.