Thin film coating having niobium-titanium layer

• US 20030165694A1
• Filed: 04/11/2002
• Published: 09/04/2003
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Inventors: Hartig, Klaus, Krisko, Annette J.
• Granted Patent: US 7,037,589 B2
• Time in Patent Office: Days
• US Class Current: 428/428
• 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 2217/734 comprising an alternation of high and low refractive indexes
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: Y10T 428/12576 Boride, carbide or nitride component
• CPC Class Codes: Y10T 428/12611 Oxide-containing component
• CPC Class Codes: Y10T 428/12618 Plural oxides
• CPC Class Codes: Y10T 428/31612 As silicone, silane or siloxane

Abstract

The invention provides niobium-titanium films, coatings (e.g., low-emissivity coatings) comprising one or more niobium-titanium films, and substrates bearings such coatings. Methods of depositing niobium-titanium films are also provided.

Claims

1. A substrate bearing a low-emissivity coating, the low-emissivity coating comprising, moving outwardly:

a) a first film layer comprising a transparent dielectric material;

b) a second film layer comprising an infrared-reflective material;

c) a third, protective film layer comprising niobium and titanium; and

d) a fourth film layer comprising a transparent dielectric material.

2. The substrate of claim 1 wherein the protective film layer contains a greater percentage of titanium than niobium, such that the protective film layer imparts abrasion resistance in the low-emissivity coating.

3. The substrate of claim 1 wherein the protective film layer contains a greater percentage of niobium than titanium, such that the protective film layer imparts in the low-emissivity coating resistance to color shifting during exposure to elevated temperatures on the order of about 700°

C.

4. The substrate of claim 1 further comprising a transparent base layer positioned between the substrate and the first film layer, the transparent base layer comprising silicon dioxide formed directly upon the substrate.

5. The substrate of claim 4 wherein the transparent base layer has a thickness of less than 100 angstroms.

6. The substrate of claim 1 wherein the protective film layer is formed directly upon the second film layer.

7. The substrate of claim 6 wherein the infrared-reflective material of the second film layer is silver.

8. The substrate of claim 1 wherein the protective film layer has a thickness of between about 10 angstroms and about 30 angstroms.

9. The substrate of claim 1 wherein the first film layer comprises zinc oxide.

10. The substrate of claim 9 wherein the second film layer is formed directly upon the first film layer and the infrared-reflective material of the second film layer is silver.

11. The substrate of claim 1 wherein the fourth film layer comprises zinc oxide.

12. The substrate of claim 1 further comprising a titanium nitride layer further from the substrate than the fourth film layer.

13. The substrate of claim 1 further comprising a chemically-durable film further from the substrate than the fourth film layer, the chemically-durable film comprising silicon nitride.

14. The substrate of claim 1 further comprising a titanium nitride layer and a chemically-durable film, both being further from the substrate than the fourth film layer, wherein the chemically-durable film comprises silicon nitride.

15. The substrate of claim 1 further comprising:

a) a fifth film layer comprising an infrared-reflective material; and

b) a sixth film layer comprising a transparent dielectric material.

16. The substrate of claim 15 further comprising a protective film layer positioned between the fifth and sixth film layers, the protective film layer comprising niobium and titanium.

17. The substrate of claim 15 further comprising a titanium nitride layer further from the substrate than the sixth film layer.

18. The substrate of claim 15 further comprising a chemically-durable film further from the substrate than the sixth film layer, the chemically-durable film comprising silicon nitride.

19. The substrate of claim 15 further comprising a titanium nitride layer and a chemically-durable film, both being further from the substrate than the sixth film layer, wherein the chemically-durable film comprises silicon nitride.

20. A substrate bearing a low-emissivity coating that includes one or more infrared-reflective films, the low-emissivity coating including a protective niobium-titanium layer that is contiguous with a protected infrared-reflective film of the coating.

21. The substrate of claim 20 wherein the protective niobium-titanium layer contains a greater percentage of titanium than niobium, such that the protective niobium-titanium layer imparts abrasion resistance in the low-emissivity coating.

22. The substrate of claim 20 wherein the protective niobium-titanium layer contains a greater percentage of niobium than titanium, such that the protective niobium-titanium layer imparts in the low-emissivity coating resistance to color shifting during exposure to elevated temperatures on the order of about 700°

C.

23. The substrate of claim 20 wherein the protective niobium-titanium layer is formed directly over said protected infrared-reflective film.

24. The substrate of claim 20 wherein said protected infrared-reflective film comprises silver.

25. The substrate of claim 20 wherein a transparent dielectric film is formed between the substrate and said protected infrared-reflective film.

26. The substrate of claim 25 wherein a transparent dielectric film is formed over the protective niobium-titanium layer.

27. The substrate of claim 20 wherein the low-emissivity coating includes a contiguous sequence of films, said contiguous sequence comprising, moving outwardly, a zinc oxide film, a silver or silver-containing film, and the protective niobium-titanium layer.

28. The substrate of claim 20 wherein the low-emissivity coating includes a sequence of films, said sequence comprising, moving outwardly, the protective niobium-titanium layer, a zinc oxide film, a silicon nitride film, a zinc oxide film, an infrared-reflective film, and a transparent dielectric film.

29. The substrate of claim 20 wherein the low-emissivity coating includes a sequence of films, said sequence comprising, moving outwardly, the protective niobium-titanium layer, a zinc oxide film, a silicon nitride film, a zinc oxide film, a silicon nitride film, a zinc oxide film, an infrared-reflective film, and a transparent dielectric film.

30. A transparent substrate having a first index of refraction, the substrate bearing a low-emissivity coating comprising, moving outwardly:

a) a transparent base layer comprising amorphous material having a second index of refraction that is substantially equal to the first index of refraction of the substrate;

b) a second film layer comprising a transparent dielectric material;

c) a third film layer comprising an infrared-reflective material;

d) a fourth, protective film layer comprising niobium and titanium; and

e) a fifth film layer comprising a transparent dielectric material.

31. The substrate of claim 30 wherein the protective film layer contains a greater percentage of titanium than niobium, such that the protective film layer imparts abrasion resistance in the low-emissivity coating.

32. The substrate of claim 30 wherein the protective film layer contains a greater percentage of niobium than titanium, such that the protective film layer imparts in the low-emissivity coating resistance to color shifting during exposure to elevated temperatures on the order of about 700°

C.

33. The substrate of claim 30 wherein the transparent base layer is formed directly upon the substrate.

34. The substrate of claim 30 wherein the transparent base layer has a thickness of less than 100 angstroms.

35. The substrate of claim 34 wherein the transparent base layer has a thickness of between about 50 angstroms and about 90 angstroms.

36. The substrate of claim 30 wherein said first index of refraction of the substrate is between about 1.4 and about 1.5.

37. The substrate of claim 30 wherein said second index of refraction of the amorphous film of the transparent base layer is less than about 1.7.

38. The substrate of claim 37 wherein the amorphous film of the transparent base layer is silicon dioxide.

39. The substrate of claim 30 wherein the infrared-reflective material of the third film layer is silver.

40. The substrate of claim 30 wherein the protective film layer has a thickness of between about 10 angstroms and about 30 angstroms.

41. The substrate of claim 30 further comprising a titanium nitride layer further from the substrate than the fifth film layer.

42. The substrate of claim 30 further comprising a chemically-durable film layer further from the substrate than the fifth film layer, the chemically-durable film layer comprising silicon nitride.

43. The substrate of claim 30 further comprising a titanium nitride layer and a chemically-durable film, both being further from the substrate than the fifth film layer, wherein the chemically-durable film layer comprises silicon nitride.

44. A substrate bearing a low-emissivity coating, the low-emissivity coating comprising, moving outwardly:

a) a first film layer comprising a transparent dielectric material;

b) a second film layer comprising an infrared-reflective material;

d) an intermediate film region comprising at least three film layers;

f) a sixth film layer comprising an infrared-reflective material;

g) a seventh film layer comprising a transparent dielectric material;

wherein the low-emissivity coating includes a protective niobium-titanium layer that is contiguous either to said second film layer or to said sixth film layer.

45. The substrate of claim 44 wherein the protective niobium-titanium layer contains a greater percentage of titanium than niobium, such that the protective niobium-titanium layer imparts abrasion resistance in the low-emissivity coating.

46. The substrate of claim 44 wherein the protective niobium-titanium layer contains a greater percentage of niobium than titanium, such that the protective niobium-titanium layer imparts in the low-emissivity coating resistance to color shifting during exposure to elevated temperatures on the order of about 700°

C.

47. The substrate of claim 44 wherein the protective niobium-titanium layer is formed directly over either said second film layer or said sixth film layer.

48. The substrate of claim 44 wherein the low-emissivity coating includes two protective niobium-titanium layers formed respectively directly over said second film layer and said sixth film layer.

49. The substrate of claim 44 wherein the protective niobium-titanium layer has a thickness of between about 10 angstroms and about 30 angstroms.

50. The substrate of claim 44 wherein each of said three film layers in the intermediate film region has a physical thickness of no more than about 250 Å

.

51. The substrate of claim 44 wherein each of said three film layers in the intermediate film region is formed of a different material than each film layer contiguous thereto.

52. The substrate of claim 44 wherein the intermediate film region comprises three film layers respectively comprising zinc oxide, silicon nitride, and zinc oxide.

53. The substrate of claim 52 wherein said silicon nitride film layer is positioned between said zinc oxide film layers.

54. The substrate of claim 44 wherein the intermediate film region comprises at least five film layers.

55. The substrate of claim 54 wherein the intermediate film region comprises alternating film layers of zinc oxide and silicon nitride.

56. The substrate of claim 55 wherein the intermediate film region comprises three zinc oxide film layers and two silicon nitride film layers.

57. The substrate of claim 44 further comprising a transparent base layer positioned between the substrate and the first film layer, the transparent base layer comprising silicon dioxide formed directly upon the substrate.

58. The substrate of claim 57 wherein the transparent base layer has a thickness of less than 100 angstroms.

59. The substrate of claim 44 further comprising a titanium nitride layer further from the substrate than the seventh film layer.

60. The substrate of claim 44 further comprising a chemically-durable film layer further from the substrate than the seventh film layer, the chemically-durable film layer comprising silicon nitride.

61. The substrate of claim 44 further comprising a titanium nitride layer and a chemically-durable film, both being further from the substrate than the seventh film layer, wherein the chemically-durable film layer comprises silicon nitride.

62. A substrate bearing a low-emissivity coating, the coating comprising, moving outwardly:

a) a first film layer comprising an oxide of zinc and tin;

b) a second film layer comprising an oxide of zinc alone;

c) a third film layer comprising an infrared-reflective material;

d) a fourth film layer comprising niobium and titanium formed directly upon the third film layer;

e) a fifth film layer comprising an oxide of zinc alone;

f) a sixth film layer comprising an oxide of zinc and tin;

g) a seventh film layer comprising an oxide of zinc alone;

h) an eighth film layer comprising an infrared-reflective material;

i) a ninth film layer comprising niobium and titanium formed directly upon the eighth film layer;

j) a tenth film layer comprising an oxide of zinc alone;

k) an eleventh film layer comprising an oxide of zinc and tin; and

l) a twelfth film layer comprising a transparent dielectric material.

63. A substrate bearing a low-emissivity coating, the low-emissivity coating comprising, moving outwardly from the substrate:

a) a first film layer comprising an oxide of titanium;

b) a second film layer comprising an oxide of zinc alone;

c) a third film layer comprising an infrared-reflective material;

d) a fourth film layer comprising niobium and titanium formed directly upon the third film layer;

e) a fifth film layer comprising silicon nitride;

f) a sixth film layer comprising an oxide of zinc alone;

g) a seventh film layer comprising an infrared-reflective material;

h) an eighth film layer comprising niobium and titanium formed directly upon the seventh film layer; and

i) a ninth film layer comprising a transparent dielectric material.

64. A method of depositing a niobium-titanium layer having abrasion resistance and resistance to color shifting during elevated temperature processing, the method comprising providing a niobium-containing sputtering target and a titanium-containing sputtering target, positioning both targets in a sputtering chamber having a sputtering cavity in which a controlled environment can be established, and delivering electric charge to both targets to sputter niobium and titanium onto a substrate having a major surface oriented toward both targets, thereby depositing niobium-titanium film upon said major surface of the substrate or upon a film layer previously deposited upon said major surface of the substrate.

65. The method of claim 64 wherein the niobium-containing target and the titanium-containing target are sputtered at substantially the same time.

66. The method of claim 64 wherein the niobium-containing target and the titanium-containing target are sputtered simultaneously.

67. The method of claim 64 wherein a first power level is selected for delivery of electric charge to the niobium-containing target and a second power level is selected for delivery of electric charge to the titanium-containing target, said power levels being selected to deposit desired percentages of niobium and titanium.

68. The method of claim 64 wherein said percentages of niobium and titanium are selected to achieve in the deposited niobium-titanium film desired levels of abrasion resistance and resistance to color shifting during exposure to elevated temperatures on the order of about 700°

C.

69. The method of claim 64 wherein the first power level is greater than said second power level.

70. The method of claim 64 wherein the second power level is greater than said first power level.