SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a transistor having a large current value in a conduction state.SOLUTION: A semiconductor device comprises: a first insulator containing excess oxygen; a first oxide semiconductor on the first insulator; a second oxide semiconductor on the first oxide semiconductor; a first conductor and a second conductor which are arranged on the second oxide semiconductor leaving an interval; a third oxide semiconductor which contacts lateral faces of the first oxide semiconductor, a top face and lateral faces of the second oxide semiconductor, a top face of the first conductor and a top face of the second conductor; a second insulator on the third oxide semiconductor; and a third conductor which faces the top face and lateral faces of the second oxide semiconductor across the second insulator and the third oxide semiconductor, in which the first oxide semiconductor has oxygen permeability higher than that of the third oxide semiconductor.