A first insulating film is formed on a semiconductor substrate. A second insulating film made of insulating metal nitride is formed on the first insulating film. A recess is formed through the second insulating film and reaches a position deeper than an upper surface of the first insulating film. A conductive member is buried in the recess. A semiconductor device is provided whose interlayer insulating film can be worked easily even if it is made to have a low dielectric constant.