Semiconductor device and display device including the same
A change in electrical characteristics in a semiconductor device including an oxide semiconductor film is inhibited, and the reliability is improved. The semiconductor device includes a gate electrode, a first insulating film over the gate electrode, an oxide semiconductor film over the first insulating film, a source electrode electrically connected to the oxide semiconductor film, a drain electrode electrically connected to the oxide semiconductor film, a second insulating film over the oxide semiconductor film, the source electrode, and the drain electrode, a first metal oxide film over the second insulating film, and a second metal oxide film over the first metal oxide film. The first metal oxide film contains at least one metal element that is the same as a metal element contained in the oxide semiconductor film. The second metal oxide film includes a region where the second metal oxide film and the first metal oxide film are mixed.
1. A semiconductor device comprising:
a gate electrode;
a first insulating film over the gate electrode;
an oxide semiconductor film including indium over the first insulating film;
a source electrode electrically connected to the oxide semiconductor film;
a drain electrode electrically connected to the oxide semiconductor film;
a second insulating film over the oxide semiconductor film, the source electrode, and the drain electrode;
a first metal oxide film over the second insulating film; and
a second metal oxide film over the first metal oxide film,
wherein the first metal oxide film includes indium,
wherein the second metal oxide film includes a metal element which is aluminum, gallium, yttrium or hafnium, and
wherein the first metal oxide film includes a region which is in contact with the second metal oxide film and includes indium and the metal element.
2. The semiconductor device according to claim 1 , further comprising a conductive film over the second metal oxide film.
3. The semiconductor device according to claim 1 ,
wherein the oxide semiconductor film comprises In, Zn, and M and
wherein M is Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf.
4. The semiconductor device according to claim 1 ,
wherein the oxide semiconductor film includes a crystal part, and
wherein the crystal part has c-axis alignment.
5. The semiconductor device according to claim 1 , wherein oxygen molecules of more than or equal to 8.0×10 14 /cm 2 are detected from the second insulating film by thermal desorption spectroscopy.
6. The semiconductor device according to claim 1 , wherein the second metal oxide film includes aluminum.
7. A display device comprising:
the semiconductor device according to claim 1 ; and
a display element.
8. A display module comprising:
the display device according to claim 7 ; and
a touch sensor.
9. An electronic device comprising:
the semiconductor device according to claim 1 ; and
at least one of an operation key and a battery.
10. A semiconductor device comprising:
a gate electrode;
a first insulating film over the gate electrode;
an oxide semiconductor film including indium over the first insulating film;
a second insulating film over the oxide semiconductor film;
a first metal oxide film over the second insulating film;
a second metal oxide film over the first metal oxide film;
a source electrode electrically connected to the oxide semiconductor film, over the second metal oxide film; and
a drain electrode electrically connected to the oxide semiconductor film, over the second metal oxide film,
wherein the first metal oxide film includes indium,
wherein the second metal oxide film includes a metal element which is aluminum, gallium, yttrium or hafnium, and
wherein the first metal oxide film includes a region which is in contact with the second metal oxide film and includes indium and the metal element.
11. The semiconductor device according to claim 10 ,
wherein the oxide semiconductor film comprises In, Zn, and M and
wherein M is Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf.
12. The semiconductor device according to claim 10 ,
wherein the oxide semiconductor film includes a crystal part, and
wherein the crystal part has c-axis alignment.
13. The semiconductor device according to claim 10 , wherein oxygen molecules of more than or equal to 8.0×10 14 /cm 2 are detected from the second insulating film by thermal desorption spectroscopy.
14. The semiconductor device according to claim 10 , wherein the second metal oxide film includes aluminum.