LASER WELDING TRANSPARENT GLASS SHEETS USING LOW MELTING GLASS OR THIN ABSORBING FILMS

• US 20150027168A1
• Filed: 05/07/2014
• Published: 01/29/2015
• Est. Priority Date: 05/10/2013
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Dabich, Leonard Charles II, Logunov, Stephan Lvovich, Quesada, Mark Alejandro, Streltsov, Alexander Mikhailovich
• Granted Patent: US 9,515,286 B2
• Time in Patent Office: Days
• US Class Current: 65/41
• CPC Class Codes: B23K 26/206 Laser sealing
• CPC Class Codes: B32B 17/06 comprising glass as the main or only constituent of a layer, next to another layer of a specific material
• CPC Class Codes: B32B 2250/03 3 layers
• CPC Class Codes: B32B 2250/40 Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• CPC Class Codes: B32B 2255/20 Inorganic coating
• CPC Class Codes: B32B 2310/0825 using IR radiation
• CPC Class Codes: B32B 2310/0831 using UV radiation
• CPC Class Codes: B32B 2310/0843 using laser
• CPC Class Codes: B32B 2457/206 Organic displays, e.g. OLED
• CPC Class Codes: B32B 37/06 characterised by the heating method
• CPC Class Codes: B32B 7/04 Interconnection of layers
• CPC Class Codes: C03B 23/203 Uniting glass sheets C03B23/24 takes precedence
• CPC Class Codes: C03C 2204/00 Glasses, glazes or enamels with special properties
• CPC Class Codes: C03C 2207/00 Compositions specially applicable for the manufacture of vitreous enamels
• CPC Class Codes: C03C 2218/32 After-treatment
• CPC Class Codes: C03C 23/0025 by a laser beam
• CPC Class Codes: C03C 27/06 Joining glass to glass by processes other than fusing fusing C03B23/20; units for use as elements for closing wall or like openings and comprising two or more parallel glass panes in spaced relationship, the panes being permanently secured together E06B3/66
• CPC Class Codes: C03C 27/08 with the aid of intervening metal
• CPC Class Codes: C03C 3/12 Silica-free oxide glass compositions
• CPC Class Codes: C03C 3/14 containing boron
• CPC Class Codes: C03C 3/16 : containing phosphorus
• CPC Class Codes: C03C 3/23 : containing halogen and at least one oxide, e.g. oxide of boron
• CPC Class Codes: C03C 3/247 : containing fluorine and phosphorus
• CPC Class Codes: C03C 4/0071 : for laserable glass
• CPC Class Codes: C03C 8/24 : Fusion seal compositions being frit compositions having non-frit additions, i.e. for use as seals between dissimilar materials, e.g. glass and metal; Glass solders
• CPC Class Codes: H10K 2102/00 : Constructional details relating to the organic devices covered by this subclass
• CPC Class Codes: H10K 50/8426 : Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 71/50 : Forming devices by joining two substrates together, e.g. lamination techniques

Abstract

A method of sealing a workpiece comprising forming an inorganic film over a surface of a first substrate, arranging a workpiece to be protected between the first substrate and a second substrate wherein the inorganic film is in contact with the second substrate; and sealing the workpiece between the first and second substrates as a function of the composition of impurities in the first or second substrates and as a function of the composition of the inorganic film by locally heating the inorganic film with a predetermined laser radiation wavelength. The inorganic film, the first substrate, or the second substrate can be transmissive at approximately 420 nm to approximately 750 nm.

Claims

1. A method of bonding a workpiece comprising:

forming an inorganic film over a surface of a first substrate;

arranging a workpiece to be protected between the first substrate and a second substrate wherein the film is in contact with the second substrate; and

bonding the workpiece between the first and second substrates by locally heating the film with laser radiation having a predetermined wavelength,

wherein the inorganic film, the first substrate, or the second substrate are transmissive at approximately 420 nm to approximately 750 nm.

2. The method of claim 1, wherein each of the inorganic film, first substrate and second substrate are transmissive at approximately 420 nm to approximately 750 nm.

3. The method of claim 1, wherein absorption of the inorganic film is more than 10% at a predetermined laser wavelength.

4. The method of claim 1, wherein the composition of the inorganic film is selected from the group consisting of SnO₂, ZnO, TiO₂, ITO, Zn, Ti, Ce, Pb, Fe, Va, Cr, Mn, Mg, Ge, SnF₂, ZnF₂ and combinations thereof.

5. The method of claim 1, wherein the composition of the inorganic film is selected to lower the activation energy for inducing creep flow of the first substrate, the second substrate, or both the first and second substrates.

6. The method of claim 1, wherein the composition of the inorganic film is a laser absorbing low liquidus temperature material with a liquidus temperature less than or equal to about 1000°

C.

7. The method of claim 1, wherein the composition of the inorganic film comprises:

20-100 mol % SnO;

0-50 mol % SnF₂; and

0-30 mol % P₂O₅ or B₂O₃.

8. The method of claim 1, wherein the inorganic film and the first and second substrates have a combined internal transmission of more than 80% at approximately 420 nm to approximately 750 nm.

9. The method of claim 1, wherein the step of bonding further comprises bonding the workpiece between the first and second substrates as a function of the composition of impurities in the first or second substrates and as a function of the composition of the inorganic film though the local heating of the inorganic film with laser radiation having a predetermined wavelength.

10. The method of claim 9 wherein the impurities in the first or second substrates are selected from the group consisting of As, Fe, Ga, K, Mn, Na, P, Sb, Ti, Zn, Sn and combinations thereof.

11. The method of claim 1, wherein the first and second substrates have different lateral dimensions, different CTEs, different thicknesses, or combinations thereof.

12. The method of claim 1, wherein one of the first and second substrates is glass or glass-ceramic.

13. The method of claim 12, wherein the other of the first and second substrates is a glass-ceramic, ceramic or metal.

14. The method of claim 1, further comprising the step of annealing the bonded workpiece.

15. The method of claim 1, wherein the laser radiation comprises UV radiation at a predetermined wavelength between approximately 193 nm to approximately 420 nm.

16. The method of claim 1, wherein the laser radiation comprises NIR radiation at a predetermined wavelength between approximately 780 nm to approximately 5000 nm.

17. The method of claim 1 wherein a pulse-width of the laser radiation is from 1 to 40 nanoseconds and a repetition rate of the laser radiation is at least 1 kHz.

18. The method of claim 1 wherein the laser radiation is continuous wave.

19. The method of claim 1, wherein a thickness of the inorganic film ranges from about 10 nm to 100 micrometers.

20. The method of claim 1, wherein the first, second or first and second substrates comprise an alkaline earth boro-aluminosilicate glass, alkali-aluminosilicate glass, soda-lime glass, boro-silicate glass, thermally strengthened glass, chemically strengthened glass, and combinations thereof.

21. The method of claim 1 further comprising the step of moving a laser spot formed by the laser radiation at a speed of approximately 1 mm/s to approximately 1000 mm/s to create a minimal heating zone.

22. The method of claim 21, wherein the speed does not exceed the product of a diameter of the laser spot and a repetition rate of the laser radiation.

23. The method of claim 1, wherein the step of bonding creates a bond line having a width of approximately 50 μ

m to approximately 1000 μ

m.

24. The method of claim 1, wherein the inorganic film, first substrate, or second substrate are optically transparent before and after the step of bonding in a range of greater than 80%, between 80% to 90%, greater than 85%, or greater than 90% at about 420 nm to about 750 nm.

25. The method of claim 1, wherein the workpiece is selected from the group consisting of a light emitting diode, an organic light emitting diode, a conductive lead, a semiconductor chip, an ITO lead, a patterned electrode, a continuous electrode, quantum dot materials, phosphor, and combinations thereof.

26. The method of claim 1, wherein the step of bonding creates a bond having an integrated bond strength greater than an integrated bond strength of a residual stress field in the first substrate, second substrate or both the first and second substrates.

27. A bonded device comprising:

an inorganic film formed over a surface of a first substrate; and

a device protected between the first substrate and a second substrate wherein the inorganic film is in contact with the second substrate,

wherein the device includes a bond formed between the first and second substrates as a function of the composition of impurities in the first or second substrates and as a function of the composition of the inorganic film though a local heating of the inorganic film with laser radiation having a predetermined wavelength, and

wherein the inorganic film, the first substrate, or the second substrate are transmissive at approximately 420 nm to approximately 750 nm.

28. The device of claim 27, wherein each of the inorganic film, first substrate and second substrate are transmissive at approximately 420 nm to approximately 750 nm.

29. The device of claim 27, wherein absorption of the inorganic film is more than 10% at a predetermined laser wavelength.

30. The device of claim 27, wherein the composition of the inorganic film is selected from the group consisting of SnO₂, ZnO, TiO₂, ITO, Zn, Ti, Ce, Pb, Fe, Va, Cr, Mn, Mg, Ge, SnF₂, ZnF₂ and combinations thereof.

31. The device of claim 27, wherein the composition of the inorganic film is selected to lower the activation energy for inducing creep flow of the first substrate, the second substrate, or both the first and second substrates.

32. The device of claim 27, wherein the composition of the inorganic film is a laser absorbing low liquidus temperature material with a liquidus temperature less than or equal to about 1000°

C.

33. The device of claim 27, wherein the composition of the inorganic film comprises:

20-100 mol % SnO;

0-50 mol % SnF₂; and

0-30 mol % P₂O₅ or B₂O₃.

34. The device of claim 27, wherein the inorganic film and the first and second substrates have a combined internal transmission of more than 80% at approximately 420 nm to approximately 750 nm.

35. The device of claim 27, wherein the impurities in the first or second substrates are selected from the group consisting of As, Fe, Ga, K, Mn, Na, P, Sb, Ti, Zn, Sn and combinations thereof.

36. The device of claim 27, wherein the first and second substrates have different lateral dimensions, different CTEs, different thicknesses, or combinations thereof.

37. The device of claim 27, wherein one of the first and second substrates is glass or glass-ceramic.

38. The device of claim 37, wherein the other of the first and second substrates is glass-ceramic, ceramic or metal.

39. The device of claim 27, wherein a thickness of the inorganic film ranges from about 10 nm to 100 micrometers.

40. The device of claim 27, wherein the first, second or first and second substrates comprise an alkaline earth boro-aluminosilicate glass, an alkali-aluminosilicate glass, a soda-lime glass, thermally strengthened glass, chemically strengthened glass, boro-silicate glass and combinations thereof.

41. The device of claim 27, wherein the inorganic film, first substrate, or second substrate are optically transparent in a range of greater than 80%, between 80% to 90%, greater than 85%, or greater than 90% at about 420 nm to about 750 nm.

42. The device of claim 27, wherein the device is selected from the group consisting of a light emitting diode, an organic light emitting diode, quantum dot material, phosphor, a conductive lead, a semiconductor chip, an ITO lead, a patterned electrode, a continuous electrode, and combinations thereof.

43. The device of claim 27, wherein the bond is hermetic with a closed loop or with seal lines crossing at angles greater than about 1 degree.

44. The device of claim 27, wherein the bond includes spatially separated bond spots.

45. The device of claim 27, wherein the bond is located at less than about 1000 μ

m from heat sensitive material of the bond.

46. The device of claim 27, wherein birefringence around the bond is patterned.

47. The device of claim 27, wherein bond has an integrated bond strength greater than an integrated bond strength of a residual stress field in the first substrate, second substrate or both the first and second substrates.

48. A method of protecting a device comprising:

forming an inorganic film layer over a first portion surface of a first substrate;

arranging a device to be protected between the first substrate and a second substrate wherein the sealing layer is in contact with the second substrate; and

locally heating the inorganic film layer and the first and second substrates with laser radiation to melt the sealing layer and the substrates to form a seal between the substrates,

wherein the first substrate is comprised of glass or glass-ceramics, and the second substrate is comprised of metal, glass-ceramics or ceramic.

49. The method of claim 48, wherein the first and second substrates have different lateral dimensions, different CTEs, different thicknesses, or combinations thereof.

50. The method of claim 48, wherein the device is selected from the group consisting of an ITO lead, a patterned electrode, and a continuous electrode.

51. The method of claim 48, wherein the step of locally heating further comprises adjusting power of the laser radiation to reduce damage to the formed seal.

52. The method of claim 48, wherein the film is made of low T_g glass, which comprises:

20-100 mol % SnO;

0-50 mol % SnF₂; and

0-30 mol % P₂O₅ or B₂O₃.

53. The method of claim 48, wherein the step of locally heating further creates a bond having an integrated bond strength greater than an integrated bond strength of a residual stress field in the first substrate, second substrate or both the first and second substrates.

54. The method of claim 48, wherein the composition of the inorganic film is selected to lower the activation energy for inducing creep flow of the first substrate, the second substrate, or both the first and second substrates.

55. The method of claim 48, wherein the composition of the inorganic film is a laser absorbing low liquidus temperature material with a liquidus temperature less than or equal to about 1000°

C.