METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

A change in electrical characteristics of a semiconductor device including an oxide semiconductor is prevented, and the reliability of the semiconductor device is improved. An oxide semiconductor is formed over a substrate; an insulator is formed over the oxide semiconductor; a metal oxide is formed over the insulator; a conductor is formed over the metal oxide; a portion of the oxide semiconductor is exposed by removing the conductor, the metal oxide, and the insulator over the oxide semiconductor; plasma treatment is performed on a surface of the exposed portion of the oxide semiconductor; and a nitride insulator is formed over the exposed portion of the oxide semiconductor and over the conductor. The plasma treatment is performed in a mixed atmosphere of an argon gas and a nitrogen gas.

主权项

1. A method for manufacturing a semiconductor device, comprising the steps of:
forming an oxide semiconductor film over a substrate; forming an insulating film over the oxide semiconductor film; forming a metal oxide film over the insulating film; forming a conductive film over the metal oxide film; exposing a portion of the oxide semiconductor film by removing a portion of the conductive film, the metal oxide film, and the insulating film over the oxide semiconductor film; performing plasma treatment on a surface of the exposed portion of the oxide semiconductor film; and forming a nitride insulating film over the exposed portion of the oxide semiconductor film and over the conductive film, wherein the plasma treatment is performed in a mixed atmosphere comprising an argon gas and a nitrogen gas.