A semiconductor device having an isolation region formed in a semiconductor substrate and a capacitance device formed above that isolation region. The capacitance device has a first capacitor conductive layer disposed above the isolation region and a second capacitor conductive layer in the shape of a side wall formed along one side surface of the first capacitor conductive layer. The second capacitor conductive layer is disposed facing the first capacitor conductive layer, with a first capacitor insulating layer interposed.