| abstract |
The invention relates to a semiconductor device having excellent electrical properties. More specifically, the invention relates to a semiconductor device having an oxide in a channel forming region, wherein: the semiconductor device comprises an oxide on a substrate, a first insulator on the oxide, a second insulating on the first insulator, a third insulator and a conductor on the third insulator; a region in which the oxide and the first insulator are in contact; an opening for exposing the oxide is disposed in the first insulator and the second insulator; the third insulator is arranged to cover the inner walls and the lower surface of the opening; the conductor is integrated in the opening; the conductor has a region that overlaps the oxide, with the third insulator between them; and the first insulator comprises an element other than the main constituent of the oxide. |