Low-E matchable coated articles, and methods

• US 6,605,358 B1
• Filed: 11/02/2001
• Issued: 08/12/2003
• Est. Priority Date: 09/13/2001
• Status: Expired due to Term

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Stachowiak, Grzegorz
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): Piziali, Andrew T
• Application Number:
  US09/985,320
• Time in Patent Office: 648 Days
• Field of Search: 428/428, 428/432, 428/448, 428/673, 428/697, 428/698, 428/699, 428/701, 428/702, 428/34, 428/689, 428/704, 427/162, 427/163.1, 427/165
• 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 17/3681 the multilayer coating being used in glazing, e.g. windows or windscreens
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: Y10T 428/12896 Ag-base component
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

A heat treatable coated article including an infrared (IR) reflecting layer (e.g., of or including Ag), the coated article being able to attain a ΔE* (glass side) no greater than about 3.5, more preferably no greater than 3.0, and even more preferably no greater than 2.6, following or due to heat treatment (e.g., thermal tempering). Accordingly, low-E (i.e., low emissivity) coated articles of certain embodiments of this invention appear from the glass side thereof visually similar to the naked eye both before and after heat treatment. Good matchability characteristics (i.e., low ΔE* values) combined with good durability can be achieved by controlling to what extent barrier layer(s) in contact with the IR reflecting layer are nitrided and to what thickness(es) they are sputtered. Optionally, certain embodiments of this invention relate to coated articles that also have high visible transmission and/or good durability. Coated articles herein may be used in the context of insulating glass (IG) window units, vehicle windows, or any other suitable applications. In certain embodiments of this invention, an exemplary layer stack includes: glass/Si₃N₄/NiCrN_x/Ag/NiCrN_x/Si₃N₄. Other materials may instead be used without departing from the scope and/or spirit of the instant invention which is a low-E matchable and/or durable product.

Claims

1. A heat treated coated article comprising:

a layer system supported by a glass substrate, said layer system comprising an infrared (IR) reflecting silver layer located between and in contact with first and second metal inclusive barrier layers; and

wherein at least said first metal inclusive barrier layer is at least partially nitrided to an extent so that said coated article has a Δ

E* value (glass side) no greater than 3.5 after or due to heat treatment (HT).

2. The coated article of claim 1, wherein said coated article has a Δ

E* value (glass side) no greater than 3.0 and a Δ

a* (glass side) no greater than 2.0 following or due to heat treatment, and said coated article has a visible transmission of at least 70% after HT.

3. The coated article of claim 1, wherein said coated article has a Δ

E* value (glass side) no greater than 2.6 and a Δ

a* (glass side) no greater than 1.0 following or due to thermal tempering of the coated article;

wherein said coated article has a color characterized by a*_G and b*_G color coordinate values of the coated article both being negative both before and after heat treatment of the coated article; and

wherein said first metal inclusive barrier layer is no more than 75% nitrided.

4. The coated article of claim 1, wherein said at least one metal inclusive barrier layer that is nitrided comprises NiCrN_x.

5. The coated article of claim 4, wherein both of said first and second metal inclusive barrier layers that are in contact with said IR reflecting silver layer comprise NiCrN_x.

6. The coated article of claim 5, wherein said coated article has good mechanical and chemical durability and a visible transmission of at least 75% after HT.

7. The coated article of claim 1, wherein at least one of said metal inclusive barrier layers comprises CrN_x.

8. The coated article of claim 7, wherein both of said metal inclusive barrier layers comprise Ni and Cr.

9. The coated article of claim 1, wherein said coated article has a sheet resistance value R_s no greater than 20 ohms/square before and after said heat treatment.

10. The coated article of claim 9, wherein said coated article has a sheet resistance value R_s no greater than 15 ohms/square after said heat treatment.

11. The coated article of claim 10, wherein both of said barrier layers comprise NiCrN_x.

12. The coated article of claim 1, further comprising a first dielectric layer located between said first metal inclusive barrier layer and said substrate, and a second dielectric layer overlying and in contact with said second metal inclusive barrier layer.

13. The coated article of claim 12, wherein each of said first and second dielectric layers comprises one of silicon nitride and/or titanium oxide of any suitable stochiometry.

14. The coated article of claim 1, wherein said layer system comprises the below-recited layers at the following thicknesses, where the first silicon nitride inclusive layer is located between the glass substrate and the first metal inclusive barrier layer:

15. The coated article of claim 14, wherein said layer system comprises the recited layers at the following thicknesses:

16. The coated article of claim 1, wherein the coated article makes up a portion of an insulating glass (IG) window unit, and wherein another dielectric layer is located between said glass substrate and said first silicon nitride inclusive layer.

17. A heat treated coated article including a layer system supported by a substrate, the heat treated coated article comprising:

a first dielectric layer on said substrate;

an IR reflecting layer sandwiched between first and second barrier layers, each of said IR reflecting layer and said barrier layers overlying said first dielectric layer;

a second dielectric layer overlying each of said first dielectric layer, said barrier layers and said IR reflecting layer; and

wherein at least one of said barrier layers comprises a metal nitride that is nitrided to an extent so that the coated article has a Δ

E* value (glass side) no greater than 2.6 after or due to heat treatment (HT).

18. The coated article of claim 17, wherein said at least one barrier layer that is nitrided comprises CrN_x.

19. The coated article of claim 18, wherein said at least one barrier layer that is nitrided comprises NiCrN_x.

20. The coated article of claim 17, wherein each of said barrier layers comprises NiCrN_x, said IR reflecting layer comprises Ag, and each of said dielectric layers comprises silicon nitride.

21. The coated article of claim 17, wherein said at least one barrier layer comprising the metal nitride is nitrided to an extent so that the metal nitride is not fully stochiometric.

22. The coated article of claim 21, wherein said at least one barrier layer is not more than 75% nitrided.

23. The coated article of claim 21, wherein said at least one barrier layer is not more than 50% nitrided.

24. A heat treated coated article including a layer system supported by a substrate, the heat treated coated article comprising:

a first dielectric layer on said substrate;

an IR reflecting layer sandwiched between and in contact with first and second metal inclusive layers, each of said IR reflecting layer and said metal inclusive layers overlying said first dielectric layer;

a second dielectric layer overlying each of said first dielectric layer, said metal inclusive layers and said IR reflecting layer; and

wherein at least one of said metal inclusive layers comprises a metal nitride that is no more than 75% nitrided so that the coated article has a Δ

E* value (glass side) no greater than 3.5 after or due to heat treatment (HT).

25. The coated article of claim 24, wherein the metal nitride is no more than 50% nitrided.

26. A method of making a heat treated coated article, the method comprising:

depositing a layer system on a glass substrate, the layer system including an infrared (IR) reflecting metal layer located between and in contact with first and second metal inclusive layers, at least one of the metal inclusive layers being nitrided to some extent, wherein prior to heat treatment the glass substrate with the layer system thereon has a sheet resistance R_s no greater than 20 ohms/square; and

heat treating the substrate with the layer system thereon so that due to said heat treating the resulting substrate with the layer system thereon has a Δ

E* value (glass side) no greater than 3.5.

27. The method of claim 26, wherein said heat treating comprises thermally tempering the substrate with the layer system thereon.

28. The method of claim 26, wherein said depositing comprises sputtering.

29. The method of claim 26, wherein the layer system comprises, from the substrate outwardly at the following thicknesses:

30. The method of claim 26, wherein due to said heat treating the resulting substrate with the layer system thereon has a Δ

E* value (glass side) no greater than 3.0, and a Δ

a* (glass side) no greater than 2.0.

31. The method of claim 26, wherein each of said first and second metal inclusive layers comprises CrN_x.

32. The method of claim 26, wherein each of said first and second metal inclusive layers comprises Ni and N.

33. The method of claim 26, wherein the at least one metal inclusive layer is nitrided, but not more than 75% nitrided.

34. The method of claim 33, wherein the at least one metal inclusive layer is not more than 50% nitrided.