SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a transistor with good electric characteristics.SOLUTION: A semiconductor device comprises: a first insulator on a substrate; a second insulator on the first insulator; an oxide semiconductor on the second insulator; a third insulator on the oxide semiconductor; a fourth insulator on the third insulator; and a first conductor on the fourth insulator. The second insulator and the third insulator contain at least one of elements other than oxygen, included in the oxide semiconductor. The first insulator and the second insulator have a region containing fluorine. It is preferable that the fourth insulator has a region containing fluorine, silicon and hafnium.SELECTED DRAWING: Figure 1