Double silver low-emissivity and solar control coatings

• US 20060147727A1
• Filed: 03/02/2006
• Published: 07/06/2006
• Est. Priority Date: 09/04/2001
• Status: Abandoned Application

• Current Assignee: AGC Flat Glass North America Incorporated (AGC, Inc.)
• Original Assignee: AFG Industries Incorporated (AGC, Inc.)
• Inventors: Dannenberg, Rang, Glenn, Darin, Johnson, Herb, Countrywood, Joe, Sieck, Peter A.
• Application Number:
  US11/365,528
• Publication Number:
  US 20060147727A1
• 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 17/3639 Multilayers containing at least two functional metal layers
• 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: G02B 5/282 reflecting for infrared and transparent for visible light, e.g. heat reflectors, laser protection
• CPC Class Codes: Y10T 428/12618 Plural oxides
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

A low-emissivity multilayer coating includes, in order outward from the substrate, a first layer including a layer containing titanium oxide, a layer containing silicon nitride, or a sublayer layer containing titanium oxide in combination with a sublayer containing silicon nitride; a second layer including Ag; a third layer including at least one layer selected from titanium oxide layers and silicon nitride layers; a fourth layer including Ag; and a fifth layer including silicon nitride. The color of the coatings can be varied over a wide range by controlling the thicknesses of the layers of titanium oxide, silicon nitride and Ag. A diffusion barrier of oxidized metal protects relatively thin, high electrical conductivity, pinhole free Ag films grown preferentially on zinc oxide substrates. Oxygen and/or nitrogen in the Ag films improves the thermal and mechanical stability of the Ag. Dividing the first layer of titanium oxide, the Ag layers, and/or the third layer with a sublayer of oxidized metal can provide greater thermal and mechanical stability to the respective layers.

Claims

1-22. -22. (canceled)

23. A low-emissivity coating on a transparent substrate, the coating comprising, in numerical order outward from the substrate,

a first layer from 5 to 20 nm thick including a silicon nitride;

a second layer from 1 to 20 nm thick including a zinc oxide;

a third layer from 10 to 14 nm thick including Ag;

a fourth layer from 2 to 8 nm thick including a partially oxidized Ni—

Cr alloy;

a fifth layer from 45 to 90 nm thick including a silicon nitride;

a sixth layer from 1 to 20 nm thick including a zinc oxide;

a seventh layer from 12 to 18 nm thick including Ag;

an eighth layer from 2 to 8 nm thick including a partially oxidized Ni—

Cr alloy; and

a ninth layer from 25 to 60 nm thick including a silicon nitride.

24. The coating according to claim 23, wherein the zinc oxide in at least one of the second layer and the sixth layer is from 6 to 7 nm thick.

25. The coating according to claim 23, wherein the zinc oxide in at least one of the second layer and the sixth layer comprises nitrogen.

26. The coating according to claim 23, wherein the Ag in the third layer is about 12 nm thick.

27. The coating according to claim 23, wherein the Ag in the seventh layer is about 16 nm thick.

28. The coating according to claim 23, wherein the Ag in at least one of the third layer and the seventh layer further includes at least one of oxygen and nitrogen.

29. The coating according to claim 28, wherein the at least one of oxygen and nitrogen is distributed homogeneously throughout the Ag.

30. The coating according to claim 23, wherein the Ag in at least one of the third layer and the seventh layer further includes a means for strengthening the Ag against thermally induced changes.

31. The coating according to claim 23, wherein the partially oxidized Ni—

Cr alloy in at least one of the fourth and the eighth layer is from 4 to 6 nm thick.

32. The coating according to claim 23, wherein at least one layer of the first layer, the third layer, the fifth layer and the seventh layer is divided by a layer including a means for strengthening the at least one layer against thermally induced changes.

33. The coating according to claim 23, wherein the fifth layer has an index of refraction greater than or equal to 1.9 at a wavelength of 550 nm.

34. The coating according to claim 23, wherein the silicon nitride in the fifth layer is about 63 nm thick.

35. The coating according to claim 23, wherein the silicon nitride in the ninth layer is about 35 nm thick.

36. The coating according to claim 23, wherein

the first layer includes a layer comprising SiN_x, where 0≦

x≦

1.34;

the fifth layer includes a layer comprising SiN_x, where 0≦

x≦

1.34; and

the ninth layer includes a layer comprising SiN_x, where 0≦

x≦

1.34.

37. The coating according to claim 36, wherein the first layer includes a layer comprising SiN_x, where x=1.34.

38. A method of making a low-emissivity coating on a substrate, the method comprising

depositing at least one layer including Ag on the substrate;

and

producing the coating of claim 23.

39. The method according to claim 38, wherein the depositing comprises sputtering.

40. A method of making a low-emissivity coating on a substrate, the method comprising

a step for depositing at least one layer including Ag on the substrate;

and

producing the coating of claim 23.