Coated article having low-E coating with IR reflecting layer(s) and niobium-doped titanium oxide dielectric layer(s) and method of making same
View Patent ↗A coated article includes a low emissivity (low-E) coating having at least one infrared (IR) reflecting layer of a material such as silver, gold, or the like, and at least one high refractive index layer of or including titanium oxide and at least one additional metal. A doped titanium oxide layer(s) is designed and deposited in a manner so as to be amorphous or substantially amorphous (as opposed to crystalline) in the low-E coating, so as to better withstand optional heat treatment (HT) such as thermal tempering and reduce haze. The high index layer may be a transparent dielectric high index layer in preferred embodiments, which may be provided for antireflection purposes and/or color adjustment purposes, in addition to having thermal stability.
1. A coated article including a coating supported by a glass substrate, the coating comprising:
a first transparent dielectric layer on the glass substrate;
an infrared (IR) reflecting layer comprising silver on the glass substrate, located over at least the first transparent dielectric layer;
a second transparent dielectric layer on the glass substrate, located over at least the IR reflecting layer;
an overcoat over the IR reflecting layer comprising silver; and
wherein the overcoat comprises a layer comprising TiNbO x , a layer comprising zinc oxide, and a layer comprising silicon nitride, wherein the layer comprising zinc oxide is located between and directly contacting the layer comprising TiNbO x and the layer comprising silicon nitride; and
wherein at least one of the first and second transparent dielectric layers is amorphous or substantially amorphous, and comprises an oxide of Ti doped with at least one of Nb, Sn, SnZn, Zr, Y, and Ba, and wherein metal content of the amorphous or substantially amorphous layer comprises from about 70-99.5% Ti and from about 0.5-30% of at least one of Nb, Sn, SnZn, Zr, Y, and Ba (atomic %).
2. The coated article of claim 1 , wherein metal content of the amorphous or substantially amorphous layer comprises from about 80-99% Ti and from about 1-20% of at least one of Nb, Sn, SnZn, Zr, Y, and Ba (atomic %).
3. The coated article of claim 1 , wherein metal content of the amorphous or substantially amorphous layer comprises from about 87-99% Ti and from about 1-13% of at least one of Nb, Sn, SnZn, Zr, Y, and Ba (atomic %).
4. The coated article of claim 1 , wherein the amorphous or substantially amorphous layer has a refractive index (n) of at least 2.12.
5. The coated article of claim 4 , wherein the amorphous or substantially amorphous layer has a refractive index (n) of at least 2.20.
6. The coated article of claim 4 , wherein the amorphous or substantially amorphous layer has a refractive index (n) of at least 2.25.
7. The coated article of claim 1 , wherein the coating is a low-E coating and has a normal emissivity (E n ) of no greater than 0.2.
8. The coated article of claim 7 , wherein the coating is a low-E coating and has a normal emissivity (E n ) of no greater than 0.10.
9. The coated article of claim 1 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and a metal content of from about 70-99.5% Ti and from about 0.5-30% Nb (atomic %).
10. The coated article of claim 9 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and a metal content comprising from about 80-99% Ti and from about 1-20% Nb (atomic %).
11. The coated article of claim 1 , wherein the first dielectric layer is said amorphous or substantially amorphous layer and is located between the glass substrate and the IR reflecting layer.
12. The coated article of claim 1 , wherein the coating comprises an overcoat including a layer comprising silicon nitride.
13. The coated article of claim 1 , wherein the coating further comprises a layer comprising silicon nitride located between at least the glass substrate and the first transparent dielectric layer.
14. The coated article of claim 1 , wherein the coating further comprises a layer comprising zinc oxide located under and directly contacting the IR reflecting layer.
15. The coated article of claim 1 , wherein the coating further comprises a layer comprising an oxide of Ni and/or Cr located over and directly contacting the IR reflecting layer.
16. The coated article of claim 1 , wherein the coated article is thermally tempered.
17. The coated article of claim 1 , wherein the coated article has a visible transmission of at least 50%.
18. The coated article of claim 1 , wherein the overcoat further comprises an uppermost layer comprising AlSiBO x .
19. A coated article including a coating supported by a glass substrate, the coating comprising:
a first transparent dielectric layer on the glass substrate;
an infrared (IR) reflecting layer on the glass substrate, located over at least the first transparent dielectric layer;
a second transparent dielectric layer on the glass substrate, located over at least the IR reflecting layer;
an overcoat over the IR reflecting layer comprising silver; and
wherein the overcoat comprises a layer comprising TiNbO x , a layer comprising zinc oxide, and a layer comprising silicon nitride, wherein the layer comprising zinc oxide is located between and directly contacting the layer comprising TiNbO x and the layer comprising silicon nitride; and
wherein at least one of the first and second transparent dielectric layers is amorphous or substantially amorphous, and comprises an oxide of Ti and Nb, and wherein metal content of the amorphous or substantially amorphous layer comprises either: (a) from about 30-70% Ti and from about 30-70% Nb (atomic %), or (b) from about 70-99.5% Ti and from about 0.5-30% of at least one of Nb.
20. A method of making a coated article including a coating supported by a glass substrate, the method comprising:
sputter depositing a first transparent dielectric layer on the glass substrate;
sputter-depositing an infrared (IR) reflecting layer comprising silver on the glass substrate, located over at least the first transparent dielectric layer;
sputter-depositing a second transparent dielectric layer on the glass substrate, located over at least the IR reflecting layer;
sputter-depositing an overcoat over the IR reflecting layer comprising silver; and
wherein the overcoat comprises a layer comprising TiNbO x , a layer comprising zinc oxide, and a layer comprising silicon nitride, wherein the layer comprising zinc oxide is located between and directly contacting the layer comprising TiNbO x and the layer comprising silicon nitride; and
wherein at least one of the first and second transparent dielectric layers is sputter-deposited so as to be amorphous or substantially amorphous, and comprise an oxide of Ti and at least one of Nb, Sn, SnZn, Zr, Y, and Ba.
21. The method of claim 20 , metal content of the amorphous or substantially amorphous layer comprises from about 70-99.5% Ti and from about 0.5-30% of at least one of Nb, Sn, SnZn, Zr, Y, and Ba (atomic %).
22. The method of claim 20 , wherein the at least one of the first and second transparent dielectric layers sputter-deposited, so as to be amorphous or substantially amorphous, is sputter-deposited in an oxygen depleted atmosphere so that a difference in radii for metals during sputtering causes lattice disorder leading to amorphous or substantially amorphous structure of the layer.
23. The method of claim 20 , wherein the coating is a low-E coating and has a normal emissivity (E n ) of no greater than 0.2.
24. The method of claim 20 , further comprising thermally tempering the glass substrate with the coating thereon.
25. The method of claim 20 , wherein the coated article has a visible transmission of at least 50%.
26. The method of claim 20 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and a metal content comprising from about 70-99.5% Ti and from about 0.5-30% Nb (atomic %).
27. The method of claim 26 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and a metal content comprising from about 80-99% Ti and from about 1-20% Nb (atomic %).
28. The method of claim 20 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and wherein during a sputtering process for depositing the oxide of Ti and Nb the layer is sputter-deposited in an oxygen depleted atmosphere comprising from 20-60% oxygen gas.
29. The method of claim 28 , wherein the amorphous or substantially amorphous layer comprises an oxide of Ti and Nb, and wherein during a sputtering process for depositing the oxide of Ti and Nb the layer is sputter-deposited in an oxygen depleted atmosphere comprising from 25-40% oxygen gas.
30. A method of making a coated article including a coating supported by a glass substrate, the method comprising:
sputter depositing a first transparent dielectric layer on the glass substrate;
sputter-depositing an infrared (IR) reflecting layer comprising silver on the glass substrate, located over at least the first transparent dielectric layer;
sputter-depositing a second transparent dielectric layer on the glass substrate, located over at least the IR reflecting layer;
sputter-depositing an overcoat over the IR reflecting layer comprising silver; and
wherein the overcoat comprises a layer comprising TiNbO x , a layer comprising zinc oxide, and a layer comprising silicon nitride, wherein the layer comprising zinc oxide is located between and directly contacting the layer comprising TiNbO x and the layer comprising silicon nitride; and
wherein at least one of the first and second transparent dielectric layers is sputter-deposited so as to be amorphous or substantially amorphous, and comprise an oxide of Ti and Nb; and
wherein during a sputtering process for depositing the layer comprising the oxide of Ti and Nb the layer is sputter-deposited in an oxygen depleted atmosphere comprising from 20-60% oxygen gas.
31. The method of claim 30 , wherein the oxygen depleted atmosphere contains from 25-40% oxygen gas.