| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device having excellent electrical characteristics.SOLUTION: The semiconductor device has a first insulator, a second insulator, a first oxide semiconductor, a second oxide semiconductor, a first conductor and a second conductor. The first oxide semiconductor is arranged on the first insulator and the second oxide semiconductor is arranged on the first oxide semiconductor. The first conductor has a region which contacts a top face of the second oxide semiconductor and the second insulator has a region which contacts the top face of the second oxide semiconductor. The second conductor is arranged on the second oxide semiconductor via the second insulator. The second oxide semiconductor has a first layer and a second layer, in which the first layer has a region which contacts the first oxide semiconductor and the second layer has a region which contacts the second insulator. The first layer has a rate of oxygen defect lower than that of the second layer. |
