In a semiconductor device and a method of manufacturing the same, a substrate is defined into active and non-active regions by a device isolation layer and a recessed portion is formed on the active region. A gate electrode includes a gate insulation layer on an inner sidewall and a bottom of the recessed portion, a lower electrode on the gate insulation layer and an inner spacer on the lower electrode in the recessed portion, and an upper electrode that is positioned on the inner spacer and connected to the lower electrode. Source and drain impurity regions are formed at surface portions of the active region of the substrate adjacent to the upper electrode. Accordingly, the source and drain impurity regions are electrically insulated by the inner spacer in the recessed portion of the substrate like a bridge, to thereby sufficiently prevent gate-induced drain leakage (GIDL) at the gate electrode.