| 摘要 |
The present invention is to provide a semiconductor device which has transistors having different threshold voltages. Alternatively, the present invention is to provide a semiconductor device which has multiple kinds of circuits and has a transistor whose electrical characteristics are different between the circuits. The semiconductor device comprises: a first transistor and a second transistor. The first transistor includes an oxide semiconductor, a conductor, a first insulator, a second insulator, and a third insulator. The conductor has an area where the conductor and the oxide semiconductor are overlapped. The first insulator is disposed between the conductor and the oxide semiconductor. The second insulator is disposed between the conductor and the first insulator. The third insulator is disposed between the conductor and the second insulator. The second insulator has an area charged negatively. |
