| abstract |
An object of the present invention is to provide stable electrical properties to a transistor using an oxide semiconductor film. In addition, the transistor using the oxide semiconductor film provides excellent electrical properties. Furthermore, a highly reliable semiconductor device having this transistor is provided. For a multilayer film in which an oxide semiconductor film and an oxide film are stacked, and a transistor having a gate electrode and a gate insulating film, the multilayer film is formed by sandwiching a gate insulating film therebetween and overlapping the gate electrode, and the multilayer film is formed of It has a shape having a first angle between the side surfaces, and a second angle between the bottom surface of the oxide film and the side surface of the oxide film, and the first angle is smaller than the second angle and is also an acute angle. Moreover, a semiconductor device is manufactured by using this transistor. |