Coater having interrupted conveyor system

• US 20060048708A1
• Filed: 08/29/2005
• Published: 03/09/2006
• Est. Priority Date: 09/03/2004
• Status: Active Grant

• Current Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Inventors: Hartig, Klaus
• Granted Patent: US 7,749,364 B2
• Time in Patent Office: Days
• US Class Current: 118/715
• CPC Class Codes: C03C 17/002 for flat glass, e.g. float glass
• CPC Class Codes: C03C 2218/365 Coating different sides of a glass substrate
• CPC Class Codes: C23C 14/0652 Silicon nitride
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/10 Glass or silica
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: C23C 14/56 Apparatus specially adapted for continuous coating; Arrangements for maintaining the vacuum, e.g. vacuum locks
• CPC Class Codes: C23C 14/568 Transferring the substrates through a series of coating stations C23C14/562 takes precedence

Abstract

Methods and coaters for applying films onto a substrate (e.g., a large-area glass substrate) are disclosed. Certain embodiments involve a coater for applying thin films onto a sheet-like substrate. The coater in some embodiments has a transport system adapted for conveying the substrate along a path of substrate travel extending through the coater. The substrate transport system in certain embodiments includes an upward coating deposition gap. The coater preferably has a source of coating material adapted for delivering coating material upwardly through such gap and onto a bottom major surface of the substrate as the substrate is conveyed along a desired portion of the path of substrate travel, which portion of the path of substrate travel extends over the upward coating deposition gap.

Claims

1. A coater for applying thin films onto a sheet-like substrate, the coater having a substrate transport system adapted for conveying the substrate along a path of substrate travel extending through the coater, the substrate transport system including two conveyor loops separated by an upward coating deposition gap, the coater having a source of coating material adapted for delivering coating material upwardly through said gap onto a bottom major surface of the substrate as the substrate is conveyed along a desired portion of the path of substrate travel, said desired portion of the path of substrate travel extending over the upward coating deposition gap.

2. The coater of claim 1, wherein each of said two conveyor loops comprises a conveyor sheet having a width of at least about 1 meter.

3. The coater of claim 1, wherein each of said two conveyor loops comprises a conveyor sheet having a width of at least about 2 meters.

4. The coater of claim 1, wherein each of said two conveyor loops comprises a conveyor sheet having generally-opposed lateral side edges between which the conveyor sheet forms a continuous wall devoid of gaps.

5. The coater of claim 1, wherein each of said two conveyor loops comprises a conveyor sheet having generally-opposed lateral side edges and having a major surface that is substantially entirely generally planar, such that when the bottom major surface of the substrate is positioned directly on said major surface there is a lateral extent of contact between said major surface and the substrate'"'"'s bottom surface, said lateral extent of contact extending substantially entirely between the lateral side edges of the conveyor sheet.

6. The coater of claim 1, wherein at least part of the source of coating material is positioned directly beneath the upward coating deposition gap.

7. The coater of claim 1, wherein the coater includes a deposition chamber defining an interior cavity, the path of substrate travel extends through the deposition chamber, and said source of coating material is disposed at least in part within the deposition chamber.

8. The coater of claim 7, wherein the deposition chamber is a vacuum deposition chamber adapted for carrying out at least one vacuum deposition process.

9. The coater of claim 8, wherein the vacuum deposition chamber is adapted for establishing and maintaining a gas pressure in said interior cavity of less than about 0.1 torr.

10. The coater of claim 1, wherein said source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus.

11. The coater of claim 10, wherein said source of coating material includes a sputter deposition apparatus comprising a sputtering target.

12. The coater of claim 11, wherein the sputtering target has a length, the upward coating deposition gap has a length, and the target is positioned directly beneath said gap so that the target'"'"'s length is generally parallel to the gap'"'"'s length.

13. The coater of claim 11, further comprising a power supply adapted for delivering an electric charge to the sputtering target.

14. The coater of claim 1, wherein the coater is a large-area coater and the substrate transport system is adapted for conveying substrates each having a width of at least about 1.5 meters.

15. The coater of claim 1, wherein the coater is a large-area coater and the substrate transport system is adapted for conveying substrates each having a width of at least about 2 meters.

16. The coater of claim 1, wherein the coater is a large-area coater and said source of coating material comprises a sputtering target having a length of at least about 1 meter.

17. The coater of claim 1, wherein the coater is a large-area coater and said source of coating material comprises a sputtering target having a length of at least about 1.5 meters.

18. The coater of claim 1, wherein the upward coating deposition gap has a length, said source of coating material is adapted to deliver a flux of coating material, said flux having a length that is at least about 50% as great as the length of the upward coating deposition gap.

19. The coater of claim 1, wherein the upward coating deposition gap has a length, said source of coating material is adapted to deliver a flux of coating material, said flux having a length that is at least about 75% as great as the length of the upward coating deposition gap.

20. The coater of claim 1, wherein the substrate has a width, and the upward coating deposition gap has a length that is at least as great as the substrate'"'"'s width.

21. The coater of claim 20, wherein said source of coating material is adapted for delivering a flux of coating material, said flux having a length that is at least as great as the substrate'"'"'s width, such that said source of coating material is adapted for full-area coating of the bottom major surface of the substrate.

22. The coater of claim 1, wherein the substrate has a width, and said source of coating material is a sputtering target having a length that is at least about 70% as great as the substrate'"'"'s width.

23. The coater of claim 1, wherein the substrate has a length, the upward coating deposition gap has a width, and the width of said gap is less than one half the length of the substrate.

24. A method for applying thin films onto a sheet-like substrate, the method comprising:

providing a coater having a substrate transport system defining a path of substrate travel extending through the coater, the substrate transport system including first and second conveyor loops separated by an upward coating deposition gap, the coater having a lower source of coating material positioned below said gap;

positioning the substrate on said first conveyor loop;

operating the transport system so as to convey the substrate along the path of substrate travel from said first conveyor loop to said second conveyor loop, such that the substrate during said conveyance moves over the source of coating material; and

operating the coater so as to deliver coating material upwardly from said lower source of coating material through said gap onto a bottom major surface of the substrate.

25. The method of claim 24, wherein the coater includes a series of thin film deposition apparatuses positioned on a common side of the path of substrate travel such that the deposition apparatuses of said series are above the path of substrate travel, the deposition apparatuses of said series being operated so as to deposit a low-emissivity coating on a top major surface of the substrate.

26. The method of claim 25, wherein said operation of said series of deposition apparatuses includes depositing at least one silver-containing film on the top major surface of the substrate.

27. The method of claim 25, wherein said lower source of coating material is either located at a position further along the path of substrate travel than the deposition apparatuses of said series or the deposition apparatuses of said series are located at a position further along the path of substrate travel than said lower source of coating material.

28. The method of claim 24, wherein each of said two conveyor loops comprises a conveyor sheet having a width, and the substrate is selected so as to have a width that is equal to or less than the width of the conveyor sheet.

29. The method of claim 28, wherein the width of the substrate is at least two inches less than the width of the conveyor sheet.

30. The method of claim 28, wherein the width of the substrate is at least eight inches less than the width of the conveyor sheet.

31. The method of claim 24, wherein the first conveyor loop comprises a conveyor sheet having generally-opposed lateral side edges, and the substrate when positioned on the first conveyor loop is arranged such that no portion of the substrate projects laterally past either of the lateral side edges of the conveyor sheet.

32. The method of claim 24, wherein the first conveyor loop comprises a conveyor sheet having generally-opposed lateral side edges between which the conveyor sheet forms a continuous wall devoid of gaps, such that when the substrate is on the said first conveyor loop there is a lateral extent of contact between the bottom major surface of the substrate and the conveyor sheet, said lateral extent of contact extending substantially entirely between the lateral side edges of the conveyor sheet.

33. The method of claim 24, wherein the upward coating deposition gap has a length, and the substrate is selected so as to have a width that is less than or equal to the gap'"'"'s length.

34. The method of claim 33, wherein said lower source of coating material is adapted for delivering a flux of coating material having a length, the substrate being selected so its width is less than or equal to said length of flux, such that said lower source of coating material is adapted for full-area coating of the bottom major surface of the substrate.

35. The method of claim 32, wherein said lower source of coating material is a sputtering target having a length that is at least about 70% as great as the substrate'"'"'s width.

36. The method of claim 24, wherein the upward coating deposition gap has a width, and the substrate is selected so as to have a length that is more than twice the width of said gap.

37. The method of claim 24, wherein said operation of said lower source of coating material is performed in a lower region of a desired chamber of the coater, said desired chamber including an upper region that either is equipped with no upper thin film deposition apparatus or is equipped with an upper deposition apparatus that is maintained in a non-depositing condition during said operation of said lower source of coating material.

38. The method of claim 37, wherein said operation of said lower source of coating material is performed while an oxidizing atmosphere is maintained in said lower region of said desired chamber of the coater.

39. A coater for applying thin films onto two generally-opposed major surfaces of a sheet-like substrate, the coater having a substrate transport system adapted for conveying the substrate along a path of substrate travel extending through the coater, the substrate transport system including two conveyor loops separated by an upward coating deposition gap, the coater having an upper source of coating material positioned above the path of substrate travel and a lower source of coating material positioned below the path of substrate travel, said upper source being adapted for delivering coating material downwardly toward the path of substrate travel, said lower source being adapted for delivering coating material upwardly through said gap toward the path of substrate travel.

40. The coater of claim 39, wherein the coater includes a vacuum deposition chamber defining an interior cavity, the path of substrate travel extends through the vacuum deposition chamber, and the vacuum deposition chamber is adapted for establishing and maintaining a gas pressure in said interior cavity of less than about 0.1 torr.

41. The coater of claim 39, wherein said upper source of coating material comprises a sputtering target, and said lower source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus.

42. The coater of claim 39, wherein the coater includes a series of thin film deposition apparatuses positioned on a common side of the path of substrate travel such that the deposition apparatuses of said series are either above or below the path of substrate travel, the deposition apparatuses of said series being adapted to deposit a low-emissivity coating on the substrate.

43. The coater of claim 42, said series of deposition apparatuses including at least one apparatus adapted for depositing a silver-containing film on the substrate.

44. The coater of claim 42, wherein the deposition apparatuses of said series are positioned above the path of substrate travel.

45. The coater of claim 42, wherein said series of deposition apparatuses includes sputtering targets.

46. A coater for applying thin films onto a sheet-like substrate, the coater comprising:

a substrate transport system adapted for conveying the substrate through the coater, the substrate transport system having a conveyor loop defining a pocket; and

a source of coating material disposed at least partially within the pocket defined by the conveyor loop of the substrate transport system.

47. The coater of claim 46, wherein the substrate transport system defines a path of substrate travel extending through the coater, and said source of coating material is below the path of substrate travel.

48. The coater of claim 46, wherein said pocket is open upwardly toward the path of substrate travel, and said source of coating material is adapted for delivering coating material upwardly onto a bottom major surface of the substrate when the substrate is in a desired position on the transport system.

49. The coater of claim 46, wherein the substrate has a width, and the pocket has a length that is at least as great as the substrate'"'"'s width.

50. The coater of claim 49, wherein said source of coating material is adapted for delivering a flux of coating material, said flux having a length that is at least as great as the substrate'"'"'s width, such that said source of coating material is adapted for full-area coating of a bottom major surface of the substrate.

51. The coater of claim 49, wherein said source of coating material is a sputtering target having a length that is at least about 70% as great as the substrate'"'"'s width.

52. The coater of claim 46, wherein the substrate has a length, the pocket has a width, and the width of the pocket is less than one half the length of the substrate.

53. The coater of claim 46, wherein the coater includes a deposition chamber defining an interior cavity, the substrate transport system defines a path of substrate travel extending through the deposition chamber, and said source of coating material is disposed at least in part within the deposition chamber.

54. The coater of claim 53, wherein the deposition chamber is a vacuum deposition chamber adapted for carrying out at least one vacuum deposition process.

55. The coater of claim 54, wherein the vacuum deposition chamber is adapted for establishing and maintaining a gas pressure in said interior cavity of less than about 0.1 torr.

56. The coater of claim 46, wherein said source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus.

57. The coater of claim 56, wherein said source of coating material includes a sputter deposition apparatus comprising a sputtering target.

58. The coater of claim 57, wherein the sputtering target is disposed at least partially within the pocket defined by the conveyor loop of the substrate transport system.

59. The coater of claim 58, further comprising a gas-delivery outlet disposed within the pocket defined by the conveyor loop of the substrate transport system.

60. The coater of claim 59, further comprising a gas supply coupled with, and/or adapted for being coupled with, a gas-delivery line leading to the gas-delivery outlet.

61. The coater of claim 58, further comprising an anode disposed at least partially within the pocket defined by the conveyor loop of the substrate transport system.

62. The coater of claim 61, further comprising a power supply for providing a voltage differential between the sputtering target and the anode.

63. The coater of claim 46, wherein the pocket is bounded by a generally-horizontal portion of the conveyor loop and by two generally-vertical confronting portions of the conveyor loop.

64. A method for applying thin films onto a sheet-like substrate, the method comprising:

providing a coater having a substrate transport system adapted for conveying the substrate through the coater, the substrate transport system having a conveyor loop defining a pocket, the coater further comprising a source of coating material disposed at least partially within said pocket;

positioning the substrate on the conveyor loop;

operating the transport system so as to convey the substrate through the coater; and

operating the coater so as to deliver coating material from the source of coating material outwardly from said pocket onto a desired major surface of the substrate.

65. The method of claim 64 wherein the coating material delivered onto the desired major surface coats such surface entirely.

66. A method for applying thin films onto a sheet-like substrate, the method comprising:

providing a coater having a substrate transport system adapted for conveying the substrate along a path of substrate travel extending through the coater, the substrate transport system having a conveyor loop defining a pocket that is open upwardly toward the path of substrate travel, the coater having a source of coating material below the path of substrate travel, the source of coating material being disposed at least partially within said pocket;

positioning the substrate on the conveyor loop;

operating the transport system so as to convey the substrate along the path of substrate travel such that the substrate moves over the source of coating material; and

operating the coater so as to deliver coating material from the source of coating material upwardly from said pocket and onto a bottom major surface of the substrate.

67. The method of claim 66, wherein the coating material delivered onto the bottom major surface coats such surface entirely.

68. The method of claim 66, wherein the substrate is a sheet of glass, the coater is a vacuum coater, and the source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus.

69. A coater for applying thin films onto two generally-opposed major surfaces of a sheet-like glass substrate having a major dimension of at least 1 meter, the coater having a substrate transport system adapted for conveying the glass substrate along a path of substrate travel extending through the coater, the substrate transport system having a conveyor with an upward coating deposition gap, the coater including an upper source of coating material positioned above the path of substrate travel and a lower source of coating material positioned below the path of substrate travel, said upper source being adapted for delivering coating material downwardly toward the path of substrate travel, said lower source being adapted for delivering coating material upwardly through said gap toward the path of substrate travel, wherein the upper source of coating material comprises a sputtering target, and the lower source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus.

70. The coater of claim 69, wherein said conveyor includes two conveyor loops separated by said upward coating deposition gap, wherein each conveyor loop comprises a conveyor sheet.

71. A method for applying thin films onto two generally-opposed major surfaces of a sheet-like glass substrate having a major dimension of at least 1 meter, the method comprising:

providing a coater having a substrate transport system adapted for conveying the glass substrate along a path of substrate travel extending through the coater, the substrate transport system having a conveyor with an upward coating deposition gap, the coater including an upper source of coating material positioned above the path of substrate travel and a lower source of coating material positioned below the path of substrate travel, said upper source being adapted for delivering coating material downwardly toward the path of substrate travel, said lower source being adapted for delivering coating material upwardly through said gap toward the path of substrate travel, wherein the upper source of coating material comprises a sputtering target, and the lower source of coating material includes a thin film deposition apparatus selected from the group consisting of a sputter deposition apparatus, an ion-assisted deposition apparatus, a chemical vapor deposition apparatus, and a vacuum evaporation apparatus;

positioning the substrate on the conveyor;

operating the transport system so as to convey the substrate along the path of substrate travel, such that the substrate during said conveyance moves over the lower source of coating material;

operating the coater so as to deliver coating material upwardly from the lower source of coating material through said gap onto a bottom major surface of the substrate; and

operating the coater so as to deliver coating material downwardly from the upper source of coating material onto a top major surface of the substrate.

72. The method of claim 71, wherein the top and bottom major surfaces of the substrate are entirely coated in a single pass of the substrate through the coater.

73. The method of claim 71, wherein the lower source of coating material comprises titanium, the bottom major surface of the substrate being coated with a titanium oxide film.