Disclosed is a semiconductor device comprising a semiconductor substrate,
a capacitor provided above the semiconductor substrate, an insulation region which
covers the capacitor and has a first hole and a second hole, the first hole being
provided apart from the capacitor and extending in a vertical direction with respect
to a main surface of the semiconductor substrate, the second hole reaching an electrode
of the capacitor, extending in the vertical direction with respect to the main
surface of the semiconductor substrate and being shallower than the first hole,
a tungsten plug provided in the first hole, a first oxygen barrier film provided
between the tungsten plug and a side wall of the first hole, and a conductive plug
provided in the second hole and connected to the electrode of the capacitor.
