Methods and equipment for depositing high quality reflective coatings

• US 20070082124A1
• Filed: 10/11/2006
• Published: 04/12/2007
• Est. Priority Date: 10/11/2005
• Status: Abandoned Application

• Current Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Inventors: Hartig, Klaus
• Application Number:
  US11/546,152
• Publication Number:
  US 20070082124A1
• Time in Patent Office: Days
• US Class Current: 427/109
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3613 Coatings of type glass/inorganic compound/metal/inorganic compound/metal/other
• 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 17/3642 the multilayer coating containing a metal layer
• 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 2217/211 SnO2
• CPC Class Codes: C03C 2217/216 ZnO
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C03C 2218/153 by plasma-enhanced cvd
• CPC Class Codes: C03C 2218/154 by sputtering
• CPC Class Codes: C03C 2218/156 by magnetron sputtering
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: C23C 14/35 by application of a magnetic field, e.g. magnetron sputtering C23C14/3457 takes precedence
• CPC Class Codes: C23C 14/568 Transferring the substrates through a series of coating stations C23C14/562 takes precedence
• CPC Class Codes: E06B 2009/2417 Light path control; means to control reflection
• CPC Class Codes: E06B 3/6715 : specially adapted for increased thermal insulation or for controlled passage of light E06B3/66323 takes precedence; coating of glass pains C03C17/00; devices or arrangements for controlling the intensity, colour, phase, polarisation or direction of light G02F1/00
• CPC Class Codes: E06B 9/24 : Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; Slat blindsoperating, guiding or securing devices or arrangements for roll-type closures E06B9/56; free-hanging flexible screens A47H23/00
• CPC Class Codes: G02B 5/208 : for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G02B 5/26 : Reflecting filters G02B5/28 takes precedence
• CPC Class Codes: Y02B 80/22 : Glazing, e.g. vaccum glazing
• CPC Class Codes: Y10T 428/24612 : Composite web or sheet
• CPC Class Codes: Y10T 428/24942 : including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24975 : No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/31504 : Composite [nonstructural laminate]

Abstract

Methods and equipment for depositing coatings on glass and other substrates. In some embodiments, methods and equipment are provided for depositing reflective thin film coatings, such as low-emissivity coatings that are particularly reflective of infrared radiation, optionally by a downward coating operation. In some embodiments, such a downward coating operation is coupled with an upward coating operation used to deposit another coating.

Claims

1. A method for depositing film onto a glass sheet, the method comprising:

a) providing a coater having a path of substrate travel extending through the coater, the coater including downward coating equipment mounted above the path of substrate travel;

b) conveying the glass sheet along the path of substrate travel in a generally horizontal orientation wherein a top major surface of the glass sheet is oriented upwardly and a bottom major surface of the glass sheet is oriented downwardly; and

c) operating the downward coating equipment to deposit upon the top major surface of the glass sheet a coating including a sequence of at least seven film regions comprising, moving outwardly from the top major surface of the glass sheet, a first transparent dielectric film region, a first infrared-reflective film region comprising silver, a second transparent dielectric film region, a second infrared-reflective film region comprising silver, a third transparent dielectric film region, a third infrared-reflective film region comprising silver, and a fourth transparent dielectric film region;

the method comprising depositing said at least seven film regions in a single pass of the glass sheet through the coater, and wherein during this single pass the glass sheet is conveyed at a conveyance rate exceeding 275 inches per minute.

2. The method of claim 1 wherein the coater has an upward sputtering section and a downward sputtering section, the upward sputtering section being characterized by a series of lower targets mounted at a lower elevation than the path of substrate travel, the downward sputtering section being characterized by a series of upper targets mounted at a higher elevation than the path of substrate travel, wherein oxidizing sputtering atmospheres are maintained in all sputtering chambers of the upward sputtering section, and wherein nitriding sputtering atmospheres are maintained in a plurality of sputtering chambers of the downward sputtering section, the method comprising reactively sputtering all the lower targets upwardly in oxidizing gas and reactively sputtering a plurality of the upper targets downwardly in nitriding gas.

3. The method of claim 1 wherein the conveyance rate is 300 inches per minute or faster.

4. The method of claim 1 wherein said infrared-reflective film regions are deposited by sputtering silver-containing targets at an average power exceeding 8.5 kW.

5. The method of claim 1 wherein the conveyance rate is 310 inches per minute or faster, said infrared-reflective film regions are deposited by sputtering silver-containing targets, and at least one of the silver-containing targets is sputtered at a power exceeding 12 kW.

6. The method of claim 1 wherein said infrared-reflective film regions are deposited by sputtering silver-containing targets, a first power level is used for sputtering a silver-containing target in depositing the first infrared-reflective film region, a second power level is used for sputtering a silver-containing target in depositing the second infrared-reflective film region, and a third power level is used for sputtering a silver-containing target in depositing the third infrared-reflective film region, the third power level being greater than the second power level, and the second power level being greater than the first power level.

7. The method of claim 1 wherein the coater has an extended series of sputtering chambers and includes upward coating equipment mounted below the path of substrate travel, the upward coating equipment comprising lower sputter targets mounted at a lower elevation than the path of substrate travel, the downward coating equipment comprising upper sputter targets mounted at a higher elevation than the path of substrate travel, wherein the coater'"'"'s extended series of sputtering chambers includes at least 39 downward sputtering chambers each including at least one of the upper sputter targets.

8. The method of claim 7 wherein the coater'"'"'s extended series of sputtering chambers includes at least 55 sputtering chambers.

9. The method of claim 7 wherein the downward coating equipment is operated to deposit said coating upon the top major surface of the glass sheet, including:

depositing at least 50 angstroms of transparent dielectric film between the top major surface of the glass sheet and the first infrared-reflective film region;

depositing at least 100 angstroms of transparent dielectric film between the first and second infrared-reflective film regions;

depositing at least 100 angstroms of transparent dielectric film between the second and third infrared-reflective film regions; and

depositing at least 50 angstroms of transparent dielectric film over the third infrared-reflective film region.

10. The method of claim 9 wherein said operation of the downward coating equipment includes:

depositing no more than 175 angstroms of transparent dielectric film between the top major surface of the glass sheet and the first infrared-reflective film region.

11. The method of claim 1 wherein the coater has an extended series of sputtering chambers including at least 60 sputtering chambers, the glass sheet has a major dimension of at least 2 meters, and the method comprises entirely coating both the top and bottom major surfaces of the glass sheet in said single pass of the glass sheet through the coater.

12. The method of claim 1 wherein said single pass of the glass sheet through the coater is continuous in that the glass sheet is not interrupted by removing the glass sheet from the coater during said single pass.

13. The method of claim 1 wherein said conveyance rate is maintained substantially constant throughout an entirety of said single pass of the glass sheet through the coater.

14. A coater having an extended series of sputtering chambers and a substrate support defining a path of substrate travel extending through all the sputtering chambers of the coater, wherein the substrate support is adapted for conveying along the path of substrate travel a sheet-like substrate having a major dimension of greater than 2.0 meters, the coater having an upward sputtering section and a downward sputtering section, the upward sputtering section being characterized by a series of lower targets mounted at lower elevation than the path of substrate travel, the downward sputtering section being characterized by a series of upper targets mounted at higher elevation than the path of substrate travel, the downward sputtering section having at least 39 downward sputtering chambers each including at least one of the upper targets, the upward sputtering section having a plurality of upward sputtering chambers each including at least one of the lower targets, wherein the downward sputtering chambers of the downward sputtering section form at least seven downward deposition systems comprising, in sequence along the path of substrate travel, a first downward deposition system adapted for depositing a first transparent dielectric film region, a second downward deposition system adapted for depositing a first infrared-reflective film region comprising silver, a third downward deposition system adapted for depositing a second transparent dielectric film region, a fourth downward deposition system adapted for depositing a second infrared-reflective film region comprising silver, a fifth downward deposition system adapted for depositing a third transparent dielectric film region, a sixth downward deposition system adapted for depositing a third infrared-reflective film region comprising silver, and a seventh downward deposition system adapted for depositing a fourth transparent dielectric film region.

15. The coater of claim 14 wherein the downward sputtering section has at least 42 downward sputtering chambers.

16. The coater of claim 14 wherein the downward sputtering section has at least 45 downward sputtering chambers.

17. The coater of claim 14 wherein the coater'"'"'s extended series of sputtering chambers includes at least 60 sputtering chambers.

18. The coater of claim 14 wherein the coater'"'"'s extended series of sputtering chambers includes at least 63 sputtering chambers.

19. The coater of claim 14 wherein the path of substrate travel is a substantially straight path and the coater is a vacuum coater.

20. The coater of claim 14 wherein the substrate support comprises spaced-apart transport rollers, the coater being provided in combination with a plurality of sheet-like glass substrates, the substrates being in direct physical contact with a plurality of the transport rollers.

21. A method for depositing film onto a glass sheet, the method comprising:

a) providing a coater having an extended series of sputtering chambers and a path of substrate travel extending through all the sputtering chambers of the coater, wherein the coater'"'"'s extended series of sputtering chambers includes at least 60 sputtering chambers at least some of which are adapted for downward sputtering and include upper sputtering targets mounted above the path of substrate travel;

b) conveying the glass sheet along the path of substrate travel in a generally horizontal orientation wherein a top major surface of the glass sheet is oriented upwardly and a bottom major surface of the glass sheet is oriented downwardly, the glass sheet being conveyed along at least a portion of the path of substrate travel at a conveyance rate of 300 inches per minute or faster; and

c) sputtering at least a plurality of the upper targets to deposit upon the top major surface of the glass sheet a coating comprising, moving outwardly from the top major surface of the glass sheet, a first transparent dielectric film region, a first infrared-reflective film region comprising silver, a second transparent dielectric film region, a second infrared-reflective film region comprising silver, a third transparent dielectric film region, a third infrared-reflective film region comprising silver, and a fourth transparent dielectric film region.

22. The method of claim 21 wherein the conveyance rate is 310 inches per minute or faster.

23. The method of claim 21 wherein said infrared-reflective film regions are deposited by sputtering at least three silver-containing targets at an average power exceeding 8.5 kW.

24. The method of claim 23 wherein at least one of the silver-containing targets is sputtered at a power exceeding 12 kW.

25. The method of claim 21 wherein the coater includes upward coating equipment comprising lower sputter targets mounted at a lower elevation than the path of substrate travel, the coater having at least a plurality of upward sputtering chambers each including at least one of the lower sputter targets, and wherein the method includes upwardly sputtering at least some of the lower sputtering targets to deposit film on the bottom major surface of the glass sheet.

26. A method for depositing film onto a sheet-like substrate, the method comprising:

a) providing a coater having an extended series of sputtering chambers and a path of substrate travel extending through all the sputtering chambers of the coater, wherein the coater'"'"'s extended series of sputtering chambers includes at least 60 sputtering chambers at least some of which are adapted for downward sputtering and include upper sputtering targets mounted above the path of substrate travel;

b) conveying the substrate along the path of substrate travel in a generally horizontal orientation wherein a top major surface of the substrate is oriented upwardly and a bottom major surface of the substrate is oriented downwardly, the substrate being conveyed along at least a portion of the path of substrate travel at a conveyance rate exceeding 275 inches per minute; and

c) sputtering two series of the upper targets in nitriding gas to reactively sputter deposit over the top major surface of the substrate two transparent dielectric nitride film regions, wherein an infrared-reflective film region is deposited between said two transparent dielectric nitride film regions, and wherein said two transparent dielectric nitride film regions and said infrared-reflective film region between them are part of a coating comprising, moving outwardly from the top major surface of the substrate, a first transparent dielectric film region, a first infrared-reflective film region comprising silver, a second transparent dielectric film region, a second infrared-reflective film region comprising silver, a third transparent dielectric film region, a third infrared-reflective film region comprising silver, and a fourth transparent dielectric film region.

27. The method of claim 26 wherein said reactive sputter deposition of said transparent dielectric nitride film regions results in a combined thickness of at least 100 angstroms for said transparent dielectric nitride film regions.

28. The method of claim 27 wherein said combined thickness is at least 150 angstroms.

29. The method of claim 26 wherein both of said transparent dielectric nitride film regions comprise silicon nitride.

30. The method of claim 26 wherein the coater'"'"'s extended series of sputtering chambers includes at least 63 sputtering chambers.

31. The method of claim 26 wherein during said conveyance of the substrate the method comprises simultaneously sputtering silver in at least three of the sputtering chambers adapted for downward sputtering, said three chambers being separated from one another by other chambers that contain reactive sputtering atmospheres and are adapted for sputter depositing transparent dielectric film.

32. The method of claim 31 wherein said simultaneous sputtering of silver involves applying an average power of greater than 9.0 kW on three desired ones of the upper sputtering targets.

33. A method for depositing film onto a glass sheet, the method comprising:

a) providing a coater having an extended series of sputtering chambers and a path of substrate travel extending through all the sputtering chambers of the coater, wherein the coater'"'"'s extended series of sputtering chambers includes at least 63 sputtering chambers at least some of which are adapted for downward sputtering and include upper sputtering targets mounted above the path of substrate travel;

b) conveying the glass sheet along the path of substrate travel in a generally horizontal orientation wherein a top major surface of the glass sheet is oriented upwardly and a bottom major surface of the glass sheet is oriented downwardly, the glass sheet being conveyed along at least a portion of the path of substrate travel at a conveyance rate of 300 inches per minute or faster; and

c) sputtering two series of the upper targets in nitriding gas to reactively sputter deposit over the top major surface of the substrate two transparent dielectric nitride film regions, wherein an infrared-reflective film region is deposited between said two transparent dielectric nitride film regions, and wherein said two transparent dielectric nitride film regions and said infrared-reflective film region between them are part of a coating comprising, moving outwardly from the top major surface of the substrate, a first transparent dielectric film region, a first infrared-reflective film region comprising silver, a second transparent dielectric film region, a second infrared-reflective film region comprising silver, a third transparent dielectric film region, a third infrared-reflective film region comprising silver, and a fourth transparent dielectric film region;

the method comprising sputter depositing dielectric film directly over at least one of said three infrared-reflective film regions comprising silver.

34. The method of claim 33 wherein dielectric film is sputter deposited directly over each of said three infrared-reflective film regions comprising silver.

35. The method of claim 33 wherein the dielectric film sputter deposited directly over at least one of said three infrared-reflective film regions is a layer having a thickness of 75 angstroms or less.

36. The method of claim 33 wherein the dielectric film sputter deposited directly over at least one of said three infrared-reflective film regions is a layer having a thickness of 50 angstroms or less.