Mixed metal oxide
In an aspect, a mixed metal oxide comprises or consists essentially of: a mixture comprises or consisting essentially of 0.30 to 0.69 parts by mole Mg, 0.20 to 0.69 parts by mole Zn, 0.01 to 0.30 parts by mole of a third element selected from Al and Ga, and, either, when the third element is Al, 0.00 to 0.31 parts by mole of other elements selected from metals and metalloids, or, when the third element is Ga, 0.00 to 0.15 parts by mole of other elements selected from metals and metalloids, wherein the sum of all parts by mole of Mg, Zn, the third element, and the other elements amounts to 1.00, wherein the amount in parts by mole of the other elements is lower than the amount in parts by mole of Mg and is lower than the amount in parts by mole of Zn; oxygen; and less than 0.01 parts by mole of non-metallic and non-metalloid impurities.
1. A mixed metal oxide comprising:
a mixture comprising:
0.30 to 0.69 parts by mole Mg,
0.20 to 0.69 parts by mole Zn,
0.01 to 0.30 parts by mole of a third element selected from Al and Ga, and
at least one other element selected from metals and metalloids other than Mg, Zn and the third element, wherein when the third element is Al, the at least one other element is present at greater than zero and up to 0.31 parts by mole, and wherein when the third element is Ga, the at least one other element is present at greater than zero and up to 0.15 parts by mole;
oxygen; and
less than 0.01 parts by mole of non-metallic and non-metalloid impurities,
wherein a sum of all parts by mole of Mg, Zn, the third element, and the at least one other element amounts to 1.00, and
wherein the amount in parts by mole of the at least one other element is lower than the amount in parts by mole of each of Mg and Zn.
2. The mixed metal oxide according to claim 1 , wherein the third element is Al and the at least one other element is Ga.
3. The mixed metal oxide according to claim 1 , wherein the third element is Ga and the at least one other element is Al.
4. The mixed metal oxide according to claim 1 , wherein the third element is Al and the mixture comprises:
0.30 to 0.69 parts by mole Mg;
0.30 to 0.69 parts by mole Zn;
0.01 to 0.15 parts by mole Al; and
0.00 to 0.31 parts by mole of the at least one other element selected from metals and metalloids other than Mg, Zn and Al.
5. The mixed metal oxide according to claim 4 , wherein the amount of Mg in parts by mole is within 0.05 of the amount of Zn in parts by mole.
6. The mixed metal oxide according to claim 1 , wherein the third element is Ga and the mixture comprises:
0.40 to 0.60 parts by mole Mg;
0.20 to 0.40 parts by mole Zn;
0.10 to 0.30 parts by mole Ga; and
0.00 to 0.15 parts by mole of the at least one other element selected from metals and metalloids other than Mg, Zn and Ga.
7. The mixed metal oxide according to claim 1 , wherein the third element is Ga and the mixture comprises:
0.45 to 0.55 parts by mole Mg;
0.25 to 0.35 parts by mole Zn;
0.15 to 0.25 parts by mole Ga; and
0.00 to 0.15 parts by mole of the at least one other element selected from metals and metalloids other than Mg, Zn and Ga.
8. The mixed metal oxide according to claim 1 , wherein the oxygen is present in an amount that is within 10 mole-% of a stoichiometric amount.
9. The mixed metal oxide according to claim 1 , wherein the mixed metal oxide is in an amorphous phase.
10. A method for forming a mixed metal oxide, the method comprising:
depositing a magnesium oxide, a zinc oxide, and an oxide of a third element selected from Al and Ga on a substrate to form the mixed metal oxide,
wherein the mixed metal oxide comprises:
a mixture comprising:
0.30 to 0.69 parts by mole Mg,
0.20 to 0.69 parts by mole Zn,
0.01 to 0.30 parts by mole of the third element selected from Al and Ga, and
at least one other element selected from metals and metalloids other than Mg, Zn and the third element, wherein when the third element is Al, the at least one other element is present at greater than zero and up to 0.31 parts by mole, and wherein when the third element is Ga, the at least one other element is present at greater than zero and up to 0.15 parts by mole;
oxygen; and
less than 0.01 parts by mole of non-metallic and non-metalloid impurities,
wherein a sum of all parts by mole of Mg, Zn, the third element, and the at least one other element amounts to 1.00, and
wherein the amount in parts by mole of the at least one other element is lower than the amount in parts by mole of each of Mg and Zn.
11. The method according to claim 10 , further comprising depositing one or more other oxides of the at least one other element on the substrate.
12. The method according to claim 10 , wherein the depositing is performed at a temperature lower than about 400° C.
13. The method according to claim 10 , wherein the depositing is at a temperature range of about 200 to about 400° C.
14. The method according to claim 10 , wherein the magnesium oxide, the zinc oxide, and the oxide of the third element selected from Al and Ga are deposited using physical vapor deposition.
15. The method according to claim 14 , wherein the physical vapor deposition is performed by sputtering using a magnesium oxide target, a zinc oxide target, and a target of the third element.
16. The method according to claim 15 , wherein a first AC potential field is applied to the magnesium oxide target and to the zinc oxide target at a frequency of from 100 kHz to 10 MHz, and a DC potential field is applied to the target of the third element.
17. The method according to claim 10 , wherein the substrate comprises silicon.
18. A transistor comprising a mixed metal oxide, the mixed metal oxide comprising:
a mixture comprising:
0.30 to 0.69 parts by mole Mg,
0.20 to 0.69 parts by mole Zn,
0.01 to 0.30 parts by mole of a third element selected from Al and Ga, and
at least one other element selected from metals and metalloids other than Mg, Zn and the third element, wherein when the third element is Al, the at least one other element is present at greater than zero and up to 0.31 parts by mole, and wherein when the third element is Ga, the at least one other element is present at greater than zero and up to 0.15 parts by mole;
oxygen; and
less than 0.01 parts by mole of non-metallic and non-metalloid impurities,
wherein a sum of all parts by mole of Mg, Zn, the third element, and the at least one other element amounts to 1.00, and
wherein the amount in parts by mole of the at least one other element is lower than the amount in parts by mole of each of Mg and Zn.
19. The transistor according to claim 18 , wherein the mixed metal oxide forms a channel layer.
20. The transistor according to claim 18 , wherein the transistor is a thin film transistor.