Composite oxide semiconductor, semiconductor device using the composite oxide semiconductor, and display device including the semiconductor device
A novel composite oxide semiconductor which can be used in a transistor including an oxide semiconductor film is provided. In the composite oxide semiconductor, a first region and a second region are mixed. The first region includes a plurality of first clusters containing In and oxygen as main components. The second region includes a plurality of second clusters containing Zn and oxygen as main components. The plurality of first clusters have portions connected to each other. The plurality of second clusters have portions connected to each other.
1. A composite oxide semiconductor comprising:
a first region; and
a second region,
wherein the first region comprises a plurality of first clusters comprising In and oxygen as main components,
wherein the second region comprises a plurality of second clusters comprising Zn and oxygen as main components,
wherein the plurality of first clusters are directly connected to each other in three dimensions and sandwiched by the plurality of second clusters in three dimensions, and
wherein the plurality of second clusters are connected to each other.
2. A composite oxide semiconductor comprising:
a first region; and
a second region,
wherein the first region comprises a plurality of first clusters comprising In and oxygen as main components,
wherein the second region comprises a plurality of second clusters comprising oxygen and one of or both Zn and Sn as main components,
wherein the plurality of first clusters are directly connected to each other in three dimensions and sandwiched by the plurality of second clusters in three dimensions, and
wherein the plurality of second clusters are connected to each other.
3. The composite oxide semiconductor according to claim 1 ,
wherein each of the first region and the second region does not comprise Ga.
4. The composite oxide semiconductor according to claim 1 ,
wherein the first cluster has electrical conductivity, and
wherein the second cluster has electrical semiconductivity.
5. The composite oxide semiconductor according to claim 1 ,
wherein the first cluster comprises a portion longer than or equal to 0.5 nm and shorter than or equal to 1.5 nm.
6. A semiconductor device comprising the composite oxide semiconductor according to claim 1 , further comprising:
a pair of insulating films between which the composite oxide semiconductor is sandwiched,
wherein in the case where thermal desorption spectroscopy analysis is performed in a range of higher than or equal to 100° C. and lower than or equal to 450° C., one of or both the pair of insulating films have a region where an amount of released oxygen converted into oxygen molecules is greater than or equal to 1×10 14 molecules/cm′ and less than 1×10 16 molecules/cm 2 .
7. A semiconductor device comprising the composite oxide semiconductor according to claim 2 , further comprising:
a pair of insulating films between which the composite oxide semiconductor is sandwiched,
wherein in the case where thermal desorption spectroscopy analysis is performed in a range of higher than or equal to 100° C. and lower than or equal to 450° C., one of or both the pair of insulating films have a region where an amount of released oxygen converted into oxygen molecules is greater than or equal to 1×10 14 molecules/cm′ and less than 1×10 16 molecules/cm 2 .
8. The semiconductor device according to claim 6 ,
wherein each of the first region and the second region does not comprise Ga.
9. A display device comprising:
semiconductor device according to claim 6 ; and
a display element.
10. A display module comprising:
the display device according to claim 9 ; and
a touch sensor.
11. An electronic device comprising:
semiconductor device according to claim 6 ; and
an operation key or a battery.
12. A semiconductor device comprising:
a first conductive film;
a first insulating film over the first conductive film;
an oxide semiconductor film over the first insulating film;
a second insulating film over the oxide semiconductor film; and
a second conductive film over the second insulating film,
wherein the oxide semiconductor film comprises a first region comprising In and Zn and a second region comprising In and Zn,
wherein In concentration in the first region is 2 or more times and 10 or less times In concentration in the second region,
wherein the first region comprises a plurality of first clusters directly connected to each other in three dimensions,
wherein the second region comprises a plurality of second clusters,
wherein the plurality of first clusters are sandwiched by the plurality of second clusters in three dimensions, and
wherein a diameter of the first cluster or the second cluster is greater than or equal to 0.5 nm and less than or equal to 2.5 nm.
13. A semiconductor device comprising:
an oxide semiconductor film comprising a channel formation region,
wherein the channel formation region comprises a first region comprising In and Zn and a second region comprising In and Zn,
wherein In concentration in the first region is 2 or more times and 10 or less times In concentration in the second region, and
wherein the first region comprises a plurality of clusters three-dimensionally connected to each other so as to extend in a cloud-like manner.