CHROMIUM-FREE PASSIVATION OF VAPOR DEPOSITED ALUMINUM SURFACES

• US 20110206844A1
• Filed: 02/24/2010
• Published: 08/25/2011
• Est. Priority Date: 02/24/2010
• Status: Abandoned Application

• Current Assignee: Atotech Deutschland GmbH (MKS Instruments Incorporated)
• Original Assignee: Atotech Deutschland GmbH (MKS Instruments Incorporated)
• Inventors: Wiles, Jacob Grant, Kochilla, John R.
• Application Number:
  US12/711,431
• Publication Number:
  US 20110206844A1
• Time in Patent Office: Days
• US Class Current: 427/250
• CPC Class Codes: C23C 14/16 on metallic substrates or on substrates of boron or silicon
• CPC Class Codes: C23C 14/5853 Oxidation
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: C23C 22/34 containing fluorides or complex fluorides
• CPC Class Codes: C23C 22/362 containing also zinc cations
• CPC Class Codes: C23C 22/368 containing magnesium cations
• CPC Class Codes: C23C 22/83 Chemical after-treatment

Abstract

A process for passivating a vapor-deposited aluminum layer on a substrate, including providing a substrate comprising vapor deposited aluminum on a surface thereof; treating the surface of the substrate with an aqueous substantially chromium-free composition comprising a hexafluorozirconate; and rinsing the treated surface with water. A process for passivating a vapor-deposited aluminum layer on a substrate, including vapor depositing a layer of aluminum on a substrate; treating the substrate with the vapor deposited aluminum with an aqueous substantially chromium-free composition comprising a hexafluorozirconate; and rinsing the treated substrate with water.

Claims

1. A process for passivating a vapor-deposited aluminum layer on a substrate, comprising:

providing a substrate comprising vapor deposited aluminum on a surface thereof;

treating the surface of the substrate with an aqueous substantially chromium-free composition comprising a hexafluorozirconate; and

rinsing the treated surface with water.

2. The process of claim 1 wherein the chromium-free composition comprising a hexafluorozirconate further comprises a magnesium salt, a nickel salt, a zinc salt or a combination of any two or more of a magnesium salt, a nickel salt and a zinc salt.

3. The process of claim 1 wherein the vapor deposited aluminum is applied to the surface by decomposition of a metal-containing precursor having a decomposition temperature in a surrounding atmosphere, in which the substrate is maintained at a temperature greater than the decomposition temperature of the precursor while the surrounding atmosphere is maintained at a temperature lower than the decomposition temperature of the precursor.

4. The process of claim 1 wherein the vapor deposited aluminum is applied to the surface by one or a combination of two or more of chemical vapor deposition, ion vapor deposition and physical vapor deposition.

5. The process of claim 1 wherein the substrate comprises a ferrous metal on which the aluminum is vapor deposited.

6. The process of claim 5 wherein the ferrous metal is steel.

7. The process of claim 1 wherein the aqueous chromium-free composition is free of added zinc ions.

8. The process of claim 1 wherein the aqueous chromium-free composition is free of added alkali metal ions.

9. The process of claim 1 further comprising depositing at least one additional layer over the treated layer of aluminum, wherein the additional layer comprises one or more of a metal layer or an organic coating.

10. The process of claim 1 wherein the hexafluorozirconate is provided as one or a mixture of any two or more of hexafluorozirconic acid, ammonium hexafluorozirconate, a quaternary ammonium hexafluorozirconate, an alkali metal hexafluorozirconate, an alkaline earth metal hexafluorozirconate, or a transition metal hexafluorozirconate.

11. A process for passivating a vapor-deposited aluminum layer on a substrate, comprising:

vapor depositing a layer of aluminum on a substrate;

treating the substrate with the vapor deposited aluminum with an aqueous substantially chromium-free composition comprising a hexafluorozirconate; and

rinsing the treated substrate with water.

12. The process of claim 11 wherein the chromium-free composition comprising a hexafluorozirconate further comprises a magnesium salt, a nickel salt, a zinc salt or a combination of any two or more of a magnesium salt, a nickel salt and a zinc salt.

13. The process of claim 11 wherein the vapor depositing is by decomposition of a metal-containing precursor having a decomposition temperature in a surrounding atmosphere, in which the substrate is maintained at a temperature greater than the decomposition temperature of the precursor while the surrounding atmosphere is maintained at a temperature lower than the decomposition temperature of the precursor.

14. The process of claim 11 wherein the vapor depositing is by one or a combination of two or more of chemical vapor deposition, ion vapor deposition and physical vapor deposition.

15. The process of claim 11 wherein the substrate comprises a ferrous metal.

16. The process of claim 15 wherein the ferrous metal is steel.

17. The process of claim 11 wherein the aqueous chromium-free composition is free of added zinc ions.

18. The process of claim 11 wherein the aqueous chromium-free composition is free of added alkali metal ions.

19. The process of claim 11 further comprising depositing at least one additional layer over the treated layer of aluminum, wherein the additional layer comprises one or more of a metal layer or an organic coating.

20. The process of claim 11 wherein the hexafluorozirconate is provided as one or a mixture of any two or more of hexafluorozirconic acid, ammonium hexafluorozirconate, a quaternary ammonium hexafluorozirconate, an alkali metal hexafluorozirconate, an alkaline earth metal hexafluorozirconate, or a transition metal hexafluorozirconate.