| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device with an oxide semiconductor film, including a transistor with the excellent electric characteristics.SOLUTION: A semiconductor device includes a transistor. The transistor includes a first gate electrode, a first insulating film, an oxide semiconductor film, a source electrode and a drain electrode, a second insulating film, and a second gate electrode. The oxide semiconductor film includes a first oxide semiconductor film on and in contact with the first insulating film, a second oxide semiconductor film on and in contact with the first oxide semiconductor film, and a third oxide semiconductor film including a region on and in contact with the second oxide semiconductor film. The first oxide semiconductor film to the third oxide semiconductor film contain In, Zn and M (M represents Al, Ga, Y, or Sn). The third oxide semiconductor film includes a region in contact with a side surface of the second oxide semiconductor film and a region in contact with the second insulating film. The third oxide semiconductor film includes a region containing M more than In.SELECTED DRAWING: Figure 1 |
