Flash-treated indium tin oxide coatings, production methods, and insulating glass unit transparent conductive coating technology

• US 10,060,180 B2
• Filed: 11/06/2015
• Issued: 08/28/2018
• Est. Priority Date: 01/16/2010
• Status: Active Grant

• Current Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Inventors: Burrows, Keith James, Myli, Kari B.
• Primary Examiner(s): Loney, Donald J
• Application Number:
  US14/934,706
• Publication Number:
  US 20160060163A1
• Time in Patent Office: 1,026 Days
• CPC Class Codes: B32B 17/10055 with at least one intermediate air space
• CPC Class Codes: B32B 17/10467 Variable transmission
• CPC Class Codes: C03C 17/3411 with at least two coatings of inorganic materials C03C17/36, C03C17/42 take precedence
• CPC Class Codes: C03C 2217/231 In2O3/SnO2
• CPC Class Codes: C03C 2217/94 Transparent conductive oxide layers [TCO] being part of a multilayer coating
• CPC Class Codes: C03C 2217/948 Layers comprising indium tin oxide [ITO]
• CPC Class Codes: C03C 2218/154 by sputtering
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: C23C 14/58 After-treatment
• CPC Class Codes: E06B 3/6612 Evacuated glazing units
• CPC Class Codes: E06B 3/6722 with adjustable passage of light
• CPC Class Codes: E06B 3/677 Evacuating or filling the gap between the panes ; Equilibration of inside and outside pressure; Preventing condensation in the gap between the panes by means of spacing elements E06B3/663; Cleaning the gap between the panes
• CPC Class Codes: Y02A 30/249 Glazing, e.g. vacuum glazing
• CPC Class Codes: Y02B 80/22 Glazing, e.g. vaccum glazing

Abstract

The invention provides flash-treated transparent conductive coatings based on indium tin oxide. Some embodiments provide a method that involves depositing a substoichiometric indium tin oxide film on a glass pane, and thereafter flash treating the substoichiometric indium tin oxide film to produce a flash-treated indium tin oxide film. Other embodiments provide a multiple-pane insulating glass unit having a flash-treated indium tin oxide film on an internal surface.

Claims

1. A method of producing coated glass, the method comprising providing a glass pane having opposed first and second surfaces, the method further comprising sputtering a metallic indium tin target in an oxidizing atmosphere so as to deposit a substoichiometric indium tin oxide film on the first surface of the glass pane, thereby producing a coated glass pane, the substoichiometric indium tin oxide film having a thickness of less than 1,800 Å

, a surface roughness of less than 3 nm, an optical bandgap of 400 nm or longer, and a carrier concentration of 5×

10²⁰/cm³ or less, the method further comprising flash treating the substoichiometric indium tin oxide film so as to produce a flash-treated indium tin oxide film, said flash treating involves using one or more flash lamps to achieve ultra-high-power flash treatment at a peak pulse power of 20-45 kW/cm², the flash-treated indium tin oxide film having a thickness of less than 1,800 Å

, a surface roughness of less than 3 nm, an optical bandgap of 370 nm or shorter, a carrier concentration of 9×

10²⁰/cm³ or more, and a sheet resistance of less than 15 Ω

/square in combination with providing said coated glass pane with a monolithic visible transmittance of greater than 0.82.

2. The method of claim 1 wherein said flash treatment produces a carrier concentration factor of at least 5.

3. The method of claim 1 wherein the carrier concentration of the flash-treated indium tin oxide film is 9-13×

10²⁰/cm³.

4. The method of claim 1 wherein the substoichiometric indium tin oxide film has a visible absorption of greater than 7%, and the flash-treated indium tin oxide film has a visible absorption of less than 5%.

5. The method of claim 1 wherein said flash treatment produces a Δ

A of nine percent or more.

6. The method of claim 1 wherein the flash-treated indium tin oxide film has a thickness of less than 1,500 Å

and yet its sheet resistance is less than 15 Ω

/square.

7. The method of claim 6 wherein the thickness of the flash-treated indium tin oxide film is between 1,050 Å

and 1,450 Å

in combination with the monolithic visible transmittance of said coated glass pane being greater than 0.86 but less than 0.92 and the sheet resistance being greater than 10 Ω

/square but less than 13 Ω

/square.

8. The method of claim 1 wherein the flash-treated indium tin oxide film is non-porous.

9. The method of claim 1 further comprising sputter depositing an overcoat film on the substoichiometric indium tin oxide film, the overcoat film being sputter deposited to a thickness of between 100 Å

and 1,300 Å

.

10. The method of claim 1 wherein the overcoat film is formed of an oxide material and is deposited directly onto the flash-treated indium tin oxide film, and the flash-treated indium tin oxide film is deposited directly onto the first surface of the glass pane, the flash-treated indium tin oxide film having a sodium concentration of less than 100 ppm.

11. The method of claim 1 wherein the surface roughness of the flash-treated indium tin oxide film is between 1.5 nm and 3 nm.

12. The method of claim 1 wherein the second surface of the glass pane is maintained at a temperature of 150 degrees C. or less during said flash treatment.

20. The method of claim 1 wherein said flash treating involves using a flash treatment device comprising the one or more flash lamps to emit a pulse packet of 5-15 pulses, with each pulse being between 50 and 200 microseconds and such that an off-time between pulses is in a range of 50-100 microseconds.

21. The method of claim 20 wherein the pulse packet has a total energy in a range of from 18 J/cm² to 24 J/cm².

22. The method of claim 1 wherein the flash-treated indium tin oxide has a sodium concentration of less than 10 ppm.

23. The method of claim 1 wherein said coated glass has a haze level of less than 0.2.

13. A method of producing coated glass, the method comprising providing a glass pane having opposed first and second surfaces, the method further comprising sputtering a metallic indium tin target in an oxidizing atmosphere so as to deposit a substoichiometric indium tin oxide film on the first surface of the glass pane, thereby producing a coated glass pane, the substoichiometric indium tin oxide film having a thickness of greater than 100 Å

but less than 1,500 Å

, a surface roughness of greater than 1.5 nm but less than 3 nm, an optical bandgap of 400 nm or longer, and a carrier concentration of 5×

10²⁰/cm³ or less, the method further comprising flash treating the substoichiometric indium tin oxide film so as to produce a flash-treated indium tin oxide film, said flash treating involves using one or more flash lamps to achieve ultra-high-power flash treatment at a peak pulse power of 20-45 kW/cm², the flash-treated indium tin oxide film having a thickness of greater than 100 Å

but less than 1,500 Å

, a surface roughness of greater than 1.5 nm but less than 3 nm, an optical bandgap of 370 nm or shorter, a carrier concentration of 9×

10²⁰/cm³ or more, and a sheet resistance of less than 30 Ω

/square in combination with providing said coated glass pane with a monolithic visible transmittance of greater than 0.85.

14. The method of claim 13 wherein said flash treatment produces a carrier concentration factor of at least 5.

15. The method of claim 13 wherein said flash treatment produces a Δ

A of five percent or more.

16. The method of claim 13 wherein the thickness of the flash-treated indium tin oxide film is greater than 100 Å

but less than 1,100 Å

, and the flash-treated indium tin oxide film has an emissivity in the range of from 0.25 to 0.55.

17. The method of claim 13 wherein the substoichiometric indium tin oxide film has a visible absorption in the range of 7.5-12%, and the flash-treated indium tin oxide film has a visible absorption in the range of 0.5-4.5%.

18. The method of claim 13 wherein the sheet resistance of the flash-treated indium tin oxide film is less than 15 Ω

/square in combination with the monolithic visible transmittance being greater than 0.86 but less than 0.92.

19. The method of claim 13 further comprising sputter depositing an overcoat film on the substoichiometric indium tin oxide film, the overcoat film being sputter deposited to a thickness of between 100 Å

and 1,300 Å

.

24. The method of claim 13 wherein said flash treating involves using a flash treatment device comprising the one or more flash lamps to emit a pulse packet of 5-15 pulses, with each pulse being between 50 and 200 microseconds and such that an off-time between pulses is in a range of 50-100 microseconds.

25. The method of claim 24 wherein the pulse packet has a total energy in a range of from 18 J/cm² to 24 J/cm².

26. The method of claim 13 wherein the flash-treated indium tin oxide film has a sodium concentration of less than 1 ppm.

27. The method of claim 13 wherein said coated glass has a haze level of less than 0.1.

28. The method of claim 13 wherein the second surface of the glass pane is maintained at a temperature of lower than 125 degrees C. during said flash treatment.