In a semiconductor device having a capacitor and a method of fabricating the same, the semiconductor device comprises a semiconductor substrate and an insulating layer on the semiconductor substrate, a contact plug electrically connected to the semiconductor substrate and formed in the contact hole, a buffer conductive layer pattern electrically connected to the contact plug and formed on the insulating layer and the contact plug, an etching stopping layer formed on the buffer conductive layer pattern, a gap between the buffer conductive layer pattern and the etching stopping layer, a capacitor lower electrode electrically connected to the buffer conductive layer pattern and formed on the buffer conductive layer pattern. The gap is filled by a portion of the capacitor lower electrode.
