Expanding thermal plasma deposition system

• US 20050202184A1
• Filed: 03/08/2005
• Published: 09/15/2005
• Est. Priority Date: 03/09/2004
• Status: Active Grant

• Current Assignee: Exatec, LLC (Government of Saudi Arabia)
• Original Assignee: Exatec, LLC (Government of Saudi Arabia)
• Inventors: Miebach, Thomas, Gasworth, Steven M., Iacovangelo, Charles D., Mercedes, Michael W., Haag, Michael R.
• Granted Patent: US 7,595,097 B2
• Time in Patent Office: Days
• US Class Current: 427/569
• CPC Class Codes: B05D 1/62 Plasma-deposition of organic layers plasma deposition in general C23C14/00, C23C16/00
• CPC Class Codes: C23C 16/513 using plasma jets

Abstract

A system to coat a substrate includes a deposition chamber maintained at sub-atmospheric pressure, one or more arrays containing two or more expanding thermal plasma sources associated with the deposition chamber, and at least one injector containing orifices for each array. The substrate is positioned in the deposition chamber and each expanding thermal plasma source produces a plasma jet with a central axis, while the injector injects vaporized reagents into the plasma to form a coating that is deposited on the substrate. The injector orifices are located within a specified distance from the expanding thermal plasma source to obtain generally a coating with generally uniform coating properties.

Claims

1. A process for coating a substrate comprising:

generating a plasma from two or more ETP sources, each ETP source including an anode; and

injecting vaporized reagents into the plasma to form the coating on the substrate, the injection of the reagents being located within a specified distance from the anode orifice of the ETP source to obtain one or more uniform coating properties over the substrate.

2. The process of claim 1 wherein the uniform coating property is the coating thickness.

3. The process of claim 1 wherein the uniform coating property is the abrasion resistance of the coating.

4. The process of claim 1 wherein the uniform coating property is adhesion of the coating to the substrate after water immersion.

5. The process of claim 1 wherein the coating is a plasma polymerized and oxidized organosilicon.

6. The process of claim 5 wherein the organosilicon is selected from the group consisting of DMDMS, HMDSO, TMDSO, D4, and D5.

7. The process of claim 1 wherein the coating is an abrasion-resistant coating with an UV absorbency of less than about 0.02 micrometer⁻

1 at about 300 nm.

8. The process of claim 7 wherein two abrasion-resistant layers of different composition are coated on the substrate.

9. The process of claim 8 wherein the compositions differ in percent oxygen and hardness.

10. The process of claim 9 wherein the softer layer is closer to the substrate.

11. The process of claim 7 wherein three or more abrasion-resistant layers are coated on the substrate.

12. The process of claim 11 wherein one layer is softer than the others, the softer layer being closest to the substrate.

13. The process of claim 1 wherein the coating is an adhesion layer.

14. The process of claim 13 wherein the adhesion layer is selected from the group consisting of V-D4, D4, D5, VTMS, HMDSO, DMDMS, and TMDSO.

15. The process of claim 1 wherein the substrate contains a silicone hardcoat.

16. The process of claim 1 wherein the substrate contains a primer and a silicone hardcoat.

17. The process of claim 1 wherein the substrate is a plastic.

18. The process of claim 17 wherein the plastic is a polycarbonate.

19. The process of claim 1 wherein the coating includes an adhesion layer and an abrasion-resistant layer.

20. The process of claim 1 wherein the coating is a functional coating including inorganic UV filters, IR coatings, AR coatings, TCOs, barrier coatings, and combined multilayers.

21. The process of claim 1 wherein the reagent is injected into the plasma through an injector orifice located within a radius of about 0.1 to 4 inches from the orifice of the ETP source.

22. The process of claim 21 wherein the reagent is injected into the plasma within 2 inches from the orifice of the ETP source anode.

23. The process of claim 1 wherein the uniform coating property is UV absorption.

24. A system for coating large area substrates with generally uniform properties comprising:

a deposition chamber in which a substrate is positioned, the chamber being maintained at subatmospheric pressure;

two or more ETP sources associated with the deposition chamber, each ETP source including an anode, the ETP source producing a plasma jet having a central axis; and

at least one injector that injects vaporized reagents into the plasma to form a coating that is deposited on the substrate, the injection of the reagents being located within a specified distance from the anode of the ETP source.

25. The system of claim 24 wherein vaporized reagents are injected into the plasma from an injector separated from the ETP source.

26. The system of claim 24 wherein the injector is a ring manifold with a plurality of orifices.

27. The system of claim 24 wherein the injector is a racetrack manifold with a plurality of orifices.

28. The system of claim 24 wherein the injector is a straight tube manifold with a plurality of orifices.

29. The system of claim 24 wherein the injector is a single point orifice.

30. The system of claim 24 wherein vaporized reagents are injected through injector orifices located within a radius of about 0.1 to 4 inches from the orifice of the ETP source.

31. The system of claim 30 wherein vaporized reagents are injected through injector orifices located within a radius of 2 inches from the orifice of the ETP source.