Semiconductor device and manufacturing method thereof

摘要

A transistor having high field-effect mobility is provided. A transistor having stable electrical characteristics is provided. A transistor having low off-state current (current in an off state) is provided. Alternatively, a semiconductor device including the transistor is provided. The semiconductor device includes a first insulating film, an oxide semiconductor film over the first insulating film, a second insulating film over the oxide semiconductor film, and a conductive film overlapping with the oxide semiconductor film with the first insulating film or the second insulating film provided between the oxide semiconductor film and the conductive film. The composition of the oxide semiconductor film changes continuously between the first insulating film and the second insulating film.

主权项

1. A semiconductor device comprising:
a first insulating film; an oxide semiconductor film over the first insulating film; a second insulating film over the oxide semiconductor film; and a conductive film, wherein the first insulating film or the second insulating film is between the oxide semiconductor film and the conductive film, wherein the oxide semiconductor film contains indium, an element M, and zinc, and wherein the oxide semiconductor film has an element M concentration gradient that increases toward the first insulating film and an element M concentration gradient that increases toward the second insulating film.