Methods of forming a storage capacitor include forming an interlayer insulation layer having an opening therethrough on a semiconductor substrate, forming a contact plug in the opening, forming a molding oxide layer on the interlayer insulation layer and the contact plug, selectively removing portions of the molding oxide layer to form a recess above the contact plug, forming a titanium layer on a bottom surface and side surfaces of the recess, forming a titanium nitride layer on the titanium layer, and forming a titanium oxide nitride layer on the titanium nitride layer. A storage capacitor includes a semiconductor substrate, an interlayer insulation layer having a contact plug therein on the substrate, and a storage electrode on the contact plug including a titanium silicide layer, a titanium nitride layer on the titanium silicide layer, and a titanium oxide nitride layer on the titanium nitride layer.