SEMICONDUCTOR DEVICE

摘要

To provide a semiconductor device including an oxide semiconductor in which a change in electrical characteristics is suppressed or whose reliability is improved. In a semiconductor device including an oxide semiconductor film in which a channel formation region is formed, an insulating film which suppresses entry of water and contains at least nitrogen and an insulating film which suppresses entry of nitrogen released form the insulating film are provided over the oxide semiconductor film. As water entering the oxide semiconductor film, water contained in the air, water in a film provided over the insulating film which suppresses entry of water, or the like can be given. Further, as the insulating film which suppresses entry of water, a nitride insulating film can be used, and the amount of hydrogen molecules released by heating from the nitride insulating film is smaller than 5.0 x1021 molecules/cm3.