INFRARED REFLECTING LAYER SYSTEM FOR TRANSPARENT SUBSTRATE

• US 20080032157A1
• Filed: 05/17/2007
• Published: 02/07/2008
• Est. Priority Date: 05/23/2006
• Status: Active Grant

• Current Assignee: Von Ardenne Anlagentechnik GmbH
• Original Assignee: Von Ardenne Anlagentechnik GmbH
• Inventors: Koekert, Christoph, Proehl, Holger, Milde, Falk
• Granted Patent: US 8,119,194 B2
• Time in Patent Office: Days
• US Class Current: 428/701
• 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 17/3652 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: G02B 5/281 designed for the infrared light
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree

Abstract

An infrared radiation reflecting transparent layer system on a transparent substrate and a method for producing same is provided. The infrared radiation reflecting layer system comprises an infrared radiation reflecting layer sequence which includes a selective function usually consisting of a noble metal, mostly silver, or an alloy thereof and having a good selective reflectivity in the infrared range. The layer sequence is supplemented by at least one transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index arranged directly on the substrate or above the infrared radiation reflecting layer sequence.

Claims

1. Infrared radiation reflecting transparent layer system on a transparent substrate comprising:

a transparent first dielectric layer at least predominantly of an oxynitride of a metal, semiconductor or semiconductor alloy having a low to moderate refractive index arranged directly on the substrate; and

an infrared radiation reflecting layer sequence which includes a selective function layer arranged atop said first dielectric layer.

3. Infrared radiation reflecting transparent layer system according to claim 1, wherein a top layer of the layer system, looking from the substrate upward, comprises a second transparent dielectric layer at least predominantly of an oxynitride of a metal, semiconductor or semiconductor alloy having a low to moderate refractive index.

4. Infrared radiation reflecting transparent layer system according to claim 1, wherein the refractive index of said first dielectric layer having a low to moderate refractive index is approximately equal to or slightly greater than the refractive index of the substrate.

5. Infrared radiation reflecting transparent layer system according to claim 4, wherein the refractive index of said first dielectric layer having a low to moderate refractive index is in the range between 1.50 and 1.85 at the main wavelength of visible light of approximately 550 nm.

6. Infrared radiation reflecting transparent layer system according to claim 3, wherein the refractive index of said second dielectric layer having a low to moderate refractive index is between 1.50 and 1.95 at the main wavelength of visible light.

7. Infrared radiation reflecting transparent layer system according to claim 3, wherein said first and second dielectric layers having a low to moderate refractive index have approximately the same refractive index.

8. Infrared radiation reflecting transparent layer system according to claim 3 wherein said first and second dielectric layers having a low to moderate refractive index are made of the same material.

9. Infrared radiation reflecting transparent layer system according to claim 1, wherein said first dielectric layer having a low to moderate refractive index contains admixtures of other materials.

11. Infrared radiation reflecting transparent layer system according to claim 1, wherein the optical thickness of said first dielectric layer having a low to moderate refractive index is less than one-eighth of the wavelength of the spectral range of said transparent layer system for which said layer system has the best transparency.

12. Infrared radiation reflecting transparent layer system according claim 1, wherein said first dielectric layer having a low to moderate refractive index comprises a gradient layer having an oxygen and nitrogen content that declines in a direction of the function layer.

13. Infrared radiation reflecting transparent layer system according to claim 1, wherein said first dielectric layer having a low to moderate refractive index comprises a gradient layer having an oxygen or nitrogen content that declines in a direction of the function layer.

14. Infrared radiation reflecting transparent layer system according to claim 3, wherein said second dielectric layer having a low to moderate refractive index comprises a gradient layer having a declining oxygen content in a direction of the function layer.

15. Infrared radiation reflecting transparent layer system according claim 1, wherein a first transparent dielectric layer, as seen from the substrate upward, having a high refractive index of an oxide or nitride of a metal, a semiconductor or a semiconductor alloy is arranged above said first dielectric layer having a low to moderate refractive index.

16. Infrared radiation reflecting transparent layer system according to claim 15, wherein said layer sequence has a transparent second highly refractive dielectric layer containing silicon as a reflection reducing layer.

17. Infrared radiation reflecting transparent layer system according to claim 16, wherein the refractive index of at least one of said highly refractive dielectric layers amounts to approximately 1.9 to 2.6 with light of a wavelength of 550 nm.

18. Infrared radiation reflecting transparent layer system according to claim 1, wherein said layer system has more than one function layer.

19. Infrared radiation reflecting transparent layer system according to claim 1, wherein said layer system has at least one blocking layer.

20. Infrared radiation reflecting transparent layer system according to claim 1, wherein the layer system has at least one dielectric interface layer.

2. Infrared radiation reflecting transparent layer system on a transparent substrate comprising an infrared radiation reflecting layer sequence comprising a selective function layer and a reflection reducing layer and a top layer, as seen from the substrate upward, wherein said top layer of the layer system comprises a transparent dielectric layer at least predominantly of an oxynitride of a metal, semiconductor or semiconductor alloy having a low to moderate refractive index.

10. Infrared radiation reflecting transparent layer system according to claim 2, wherein the second dielectric layer having a low to moderate refractive index contains admixtures of other materials.

21. Method for manufacturing an infrared radiation reflecting transparent layer system in which an infrared radiation reflecting layer sequence is deposited by vacuum coating on a transparent substrate, said layer sequence including a selective function layer, wherein a first transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index is deposited directly on the substrate before deposition of said layer sequence.

23. Method for manufacturing an infrared radiation reflecting transparent layer system according to claim 21, wherein a second transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index is deposited as a top layer of the layer system, as seen from the substrate upward.

24. Method according to claim 23, wherein an oxynitride of silicon is deposited as at least one of said first and second dielectric layers having a low to moderate refractive index.

25. Method according to claim 24, wherein said first dielectric layer having a low to moderate refractive index is deposited with an oxygen and nitrogen content that differs from the oxygen and nitrogen content of said second dielectric layer having a low to moderate refractive index.

26. Method according to claim 24, wherein said first dielectric layer having a low to moderate refractive index is deposited with an oxygen or nitrogen content that differs from the oxygen or nitrogen content of said second dielectric layer having a low to moderate refractive index.

27. Method according to claim 23, wherein at least one of said dielectric layers having a low to moderate refractive index is applied by chemical vapor deposition methods (CVD methods) or plasma-supported CVD processes.

28. Method according to claim 23, wherein at least one of said dielectric layers having a low to moderate refractive index is applied by reactive magnetron sputtering of silicon or silicon-aluminum alloys in an atmosphere containing at least one of the gases oxygen and nitrogen.

29. Method according to claim 23, wherein at least one of said dielectric layers having a low to moderate refractive index is deposited as a gradient layer with an oxygen and nitrogen content that decreases toward the function layer.

31. Method according to claim 23, wherein a transparent first dielectric layer of an oxide or nitride of a metal, a semiconductor or a semiconductor alloy having a high refractive index is deposited directly as a bottom layer of said layer sequence on said first dielectric layer having a low to moderate refractive index.

32. Method according to claim 31, wherein a second transparent dielectric layer having a high refractive index and containing silicon is deposited as a top layer of said layer sequence.

22. Method for manufacturing an infrared radiation reflecting transparent layer system in which an infrared radiation reflecting layer sequence is deposited on a transparent substrate by vacuum coating, said layer sequence comprising a selective function layer, wherein a transparent dielectric layer of an oxynitride of a metal, a semiconductor or a semiconductor alloy having a low to moderate refractive index is deposited as a top layer of the layer system, as seen from the substrate upward.