Patent ID: 9111804
Filing Date: 2015-08-18
Classification: H01L

Abstract:
1. A method of manufacturing a semiconductor device comprising the steps of: forming a first insulating film over a gate electrode, the first insulating film comprising silicon, nitrogen and hydrogen; forming a second insulating film comprising silicon and oxygen on the first insulating film; heating the first insulating film to remove at least a portion of the hydrogen from the first insulating film; forming an oxide semiconductor film on the second insulating film after the step of heating the first insulating film, the oxide semiconductor film including a region to become a channel formation region; treating an upper surface of the oxide semiconductor film with a plasma of gas containing oxygen; forming a third insulating film over the oxide semiconductor film, the third insulating film comprising silicon and oxygen; forming a fourth insulating film over the third insulating film, the fourth insulating film comprising a nitride; and annealing the oxide semiconductor film after forming the fourth insulating film.