Semiconductor Device

摘要

To provide a semiconductor device having a structure capable of suppressing deterioration of its electrical characteristics which becomes apparent with miniaturization. The semiconductor device includes a first oxide semiconductor film over an insulating surface; a second oxide semiconductor film over the first oxide semiconductor film; a source electrode and a drain electrode in contact with the second oxide semiconductor film; a third oxide semiconductor film over the second oxide semiconductor film, the source electrode, and the drain electrode; a gate insulating film over the third oxide semiconductor film; and a gate electrode over the gate insulating film. A first interface between the gate electrode and the gate insulating film has a region closer to the insulating surface than a second interface between the first oxide semiconductor film and the second oxide semiconductor film.

主权项

1. A semiconductor device comprising:
a first oxide semiconductor film over an insulating film; a second oxide semiconductor film over and in contact with the first oxide semiconductor film; a source electrode and a drain electrode over the second oxide semiconductor film; a third oxide semiconductor film in contact with the source electrode, the drain electrode, a top surface and a side surface of the second oxide semiconductor film, a side surface of the first oxide semiconductor film, and the insulating film; a gate insulating film over the third oxide semiconductor film; and a gate electrode in contact with a tip surface of the gate insulating film, the gate electrode facing the top surface and the side surface of the second oxide semiconductor film, wherein a portion of a bottom surface of the gate electrode is located lower than an interface between the first oxide semiconductor film and the second oxide semiconductor film, and wherein a difference in height between the portion of the bottom surface of the gate electrode and the interface between the first oxide semiconductor film and the second oxide semiconductor film is greater than 0 and less than 300% of a channel width.