Coated article with zinc oxide over IR reflecting layer and corresponding method

• US 20050191501A1
• Filed: 02/27/2004
• Published: 09/01/2005
• Est. Priority Date: 02/27/2004
• Status: Active Grant

• Current Assignee: Guardian Europe S.A.R.L.. (Interguard Holding Corp.)
• Original Assignee: Centre Luxembourgeois de Recherches pour le Verre et la Ceramique SA, Grand Duche De Luxembourg Dudelange
• Inventors: Lemmer, Jean-Marc, Pallotta, Pierre, Ferreira, Jose
• Granted Patent: US 7,462,398 B2
• Time in Patent Office: Days
• US Class Current: 428/432
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3618 Coatings of type glass/inorganic compound/other inorganic layers, at least one layer being metallic
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3652 the coating stack containing at least one sacrificial layer to protect the metal from oxidation
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C23C 14/0652 Silicon nitride
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/185 by cathodic sputtering

Abstract

A coated article is provided that may be heat treated in certain example embodiments. A coating of the coated article includes a zinc oxide inclusive layer located over and contacting a contact layer that is in contact with an infrared (IR) reflecting layer of a material such as silver. It has been found that the use of such a zinc oxide inclusive layer results in improved thermal stability upon heat treatment, more neutral and/or desirable coloration, lower sheet resistance (R_s), and/or lower emissivity.

Claims

1. A coated article comprising a coating supported by a glass substrate, the coating comprising:

a dielectric layer;

a first layer comprising zinc oxide located over the dielectric layer;

an infrared (IR) reflecting layer comprising silver located over and contacting the first layer comprising zinc oxide;

a layer comprising an oxide of NiCr located over and contacting the IR reflecting layer;

a second layer comprising zinc oxide located over and contacting the layer comprising the oxide of NiCr; and

another dielectric layer located over the second layer comprising zinc oxide.

2. The coated article of claim 1, wherein at least one of the first and second layers comprising zinc oxide further comprising aluminum.

3. The coated article of claim 1, wherein the coated article is heat treated.

4. The coated article of claim 1, wherein the dielectric layer located between the substrate and the first layer comprising zinc oxide comprises an oxide of titanium.

5. The coated article of claim 1, further comprising a layer comprising silicon nitride located between the first layer comprising zinc oxide and the dielectric layer that comprises an oxide of titanium.

6. The coated article of claim 1, wherein the dielectric layer located between the substrate and the first layer comprising zinc oxide comprises silicon nitride.

7. The coated article of claim 6, wherein the silicon nitride is Si-rich so as to be represented by Si_xN_y, where x/y is from 0.76 to 1.5., more preferably from 0.8 to 1.4,

8. The coated article of claim 6, wherein the silicon nitride is Si-rich so as to be represented by Si_xN_y, where x/y is from 0.8 to 1.4.

9. The coated article of claim 6, wherein the silicon nitride comprises Si₃N₄.

10. The coated article of claim 1, wherein the coating includes only one IR reflecting layer comprising silver.

11. The coated article of claim 1, wherein said another dielectric layer comprises silicon nitride.

12. The coated article of claim 1, wherein the coated article is heat treated, and following heat treatment the coated article measured monolithically is characterized by the following:

13. The coated article of claim 1, wherein the coated article is heat treated, and following heat treatment the coated article measured monolithically is characterized by the following:

14. The coated article of claim 1, wherein the glass substrate and the coating are part of an IG window unit, wherein the IG window unit has a U-value of no greater than 1.25 W/(m²K).

15. The coated article of claim 1, wherein the glass substrate and the coating are part of an IG window unit, wherein the IG window unit has a U-value of no greater than 1.15 W/(m²K).

16. The coated article of claim 1, wherein the coated article is heat treated and has a Δ

a* value (transmissive) of no greater than 1.0 due to heat treatment.

17. The coated article of claim 1, wherein the coated article is heat treated and has a Δ

a* value (transmissive) of no greater than 0.7 due to heat treatment.

18. A coated article comprising a coating supported by a glass substrate, the coating comprising:

a first layer comprising zinc oxide located over the dielectric layer;

an infrared (IR) reflecting layer located over and contacting the first layer comprising zinc oxide;

a layer comprising an oxide of Ni and/or Cr located over and contacting the IR reflecting layer;

a second layer comprising zinc oxide located over and contacting the layer comprising the oxide of Ni and/or Cr; and

another dielectric layer located over the second layer comprising zinc oxide.

19. The coated article of claim 18, wherein at least one of the first and second layers comprising zinc oxide further comprising 1-5% aluminum.

20. The coated article of claim 18, wherein the coated article is heat treated.

21. The coated article of claim 18, further comprising at least one dielectric layer comprising titanium oxide and/or silicon nitride located between the substrate and the first layer comprising zinc oxide.

22. The coated article of claim 18, wherein the coating includes only one IR reflecting layer comprising silver, is heat treated, and has a sheet resistance no greater than 4.3 ohms/square following heat treatment.

23. The coated article of claim 18, wherein the coated article is heat treated, and following heat treatment the coated article measured monolithically is characterized by the following:

24. The coated article of claim 18, wherein the coated article is heat treated, and following heat treatment the coated article measured monolithically is characterized by the following:

25. The coated article of claim 18, wherein the glass substrate and the coating are part of an IG window unit, wherein the IG window unit has a U-value of no greater than 1.25 W/(m²K).

26. The coated article of claim 18, wherein the glass substrate and the coating are part of an IG window unit, wherein the IG window unit has a U-value of no greater than 1.15 W/(m²K).

27. The coated article of claim 18, wherein the coated article is heat treated and has a Δ

a* value (transmissive) of no greater than 1.0 due to heat treatment.

28. The coated article of claim 18, wherein the coated article is heat treated and has a Δ

a* value (transmissive) of no greater than 0.7 due to heat treatment.

29. A heat treated coated article comprising a coating supported by a glass substrate, the coating comprising:

at least one dielectric layer;

only one infrared (IR) reflecting layer comprising silver located over the at least one dielectric layer;

a layer comprising an oxide of Ni and/or Cr located over and contacting the IR reflecting layer;

a layer comprising zinc oxide located over and contacting the layer comprising the oxide of Ni and/or Cr;

another dielectric layer located over the second layer comprising zinc oxide; and

wherein following heat treatment the coated article measured monolithically is characterized by the following;

transmissive a*;

−

1.75 to 0visible transmission;

>

=85%R_s (ohms/square);

 

<

=4.3.

30. An insulating glass (IG) window unit including a heat treated coated article comprising a coating supported by a glass substrate, the coating comprising:

at least one dielectric layer;

only one infrared (IR) reflecting layer comprising silver located over the at least one dielectric layer;

a layer comprising an oxide of Ni and/or Cr located over and contacting the IR reflecting layer;

a layer comprising zinc oxide located over and contacting the layer comprising the oxide of Ni and/or Cr;

another dielectric layer located over the second layer comprising zinc oxide; and

wherein the IG unit has a visible transmission of at least 70% and a U-value of no greater than 1.25 W/(m 2K).

31. The IG window unit of claim 30, wherein the IG unit has a visible transmission of at least 75% and a U-value of no greater than 1.15 W/(m² K).