A semiconductor device with capacitive structures and a method of fabricating the same are disclosed. The semiconductor device includes a substrate, first and second trenches disposed in the substrate and separated from each other by a substrate region of the substrate, first, second, and third conductive layers disposed in the first and second trenches and on the substrate region in a stacked configuration, a nitride layer including first and second nitride portions disposed on the first and second trenches and on the substrate region, and first and second contact structures configured to provide first and second voltages to the first and second conductive layers. The first nitride portion is disposed on the first conductive layer and on sidewalls of the second and third conductive layers. The second nitride portion is disposed on the second conductive layer and on sidewalls of the third conductive layers.