Patent ID: 9117662
Filing Date: 2015-08-25
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device comprising the steps of: forming an oxide semiconductor film over an oxide insulating film; etching the oxide semiconductor film to form an island-shaped oxide semiconductor film; forming a metal film over the island-shaped oxide semiconductor film; adding oxygen to the metal film to form a metal oxide film, and adding oxygen also to the island-shaped oxide semiconductor film; forming a gate electrode over the metal oxide film; forming sidewalls in contact with side surfaces of the gate electrode; etching part of the metal oxide film where the gate electrode and the sidewalls do not overlap; forming an interlayer insulating film over the gate electrode, the sidewalls, and the island-shaped oxide semiconductor film; and forming a pair of contact plugs electrically connected to the island-shaped oxide semiconductor film through openings penetrating the interlayer insulating film.