Pre-plate treating system

• US 6,555,170 B2
• Filed: 02/08/2001
• Issued: 04/29/2003
• Est. Priority Date: 01/30/1998
• Status: Expired due to Term

• Current Assignee: Duratech Industries
• Original Assignee: Duratech Industries
• Inventors: Taylor, James M.
• Primary Examiner(s): Talbot, Brian K.
• Application Number:
  US09/779,870
• Publication Number:
  US 20010013473A1
• Time in Patent Office: 810 Days
• Field of Search: 106/105, 106/14.15, 106/14.42, 106/14.44, 106/14.18, 205/210, 205/215, 148/243, 148/282, 427/96, 427/302, 427/372.2, 427/388.1, 427/421
• US Class Current: 427/302
• CPC Class Codes: C25D 3/02 from solutions C25D5/34 - C25D5/46 take precedence
• CPC Class Codes: C25D 3/38 of copper
• CPC Class Codes: C25D 5/34 Pretreatment of metallic surfaces to be electroplated
• CPC Class Codes: H05K 3/22 Secondary treatment of printed circuits H05K3/1283 takes precedence; embedding circuits in grooves by pressure H05K3/107
• CPC Class Codes: H05K 3/241 characterised by the electroplating method; means therefor, e.g. baths or apparatus
• CPC Class Codes: H05K 3/282 for inhibiting the corrosion of the circuit, e.g. for preserving the solderability

Abstract

The invention relates in general to a method of electroplating substrates where at least a portion of the substrate is coated with a solution containing a film forming amine and sufficient acid to produce a pH of less than 6.5. The acid helps to clean the surface of the substrate, and the film forming amine forms a film on the surface of the substrate. Electroplating proceeds with greatly improved speed and efficiency, especially in low current areas.

Claims

1. A method of electroplating a substrate comprising:

providing a solution comprising from about 0.0003% to about 30% of a film forming amine and sufficient acid to produce a pH of less than about 6.5;

coating at least a portion of the substrate with the solution, thereby forming a film on the substrate, wherein said film inhibits oxidation of said substrate; and

plating the substrate.

2. The method of claim 1, wherein the coating comprises immersing the substrate in the solution.

3. The method of claim 1, wherein the coating comprises spraying said at least a portion of the substrate with the solution.

4. The method of claim 1, additionally comprising rinsing the substrate after the coating.

5. The method of claim 1, wherein said solution comprises a plurality of film forming amines.

6. The method of claim 1, wherein said solution comprises a plurality of acids.

7. The method of claim 1, wherein the acid is selected from the group consisting of phosphoric acid, sulfonic acid, hydroxyacetic acid, hydrochloric acid, sulfuric acid, sulfamic acid, formic acid, malonic acid, succinic acid, aspartic acid, mallic acid, acetic acid, citric acid, nitric acid, methane sulfonic acid, gallic acid, maleic acid, and fumaric acid.

8. The method of claim 1, wherein the solution is diluted to not less than about 1% of an initial concentration of said solution.

9. The method of claim 1, further comprising drying the substrate after the coating.

10. The method of claim 1, wherein the acid reduces the pH of said solution to below 4.

11. The method of claim 1, wherein said film forming amine is selected from the group consisting of fatty acid amines and long chain alkylamines.

12. The method of claim 1, wherein said film forming amine is selected from the group consisting of primary amines, secondary amines, tertiary amines;

alkylamines;

C-8 through C-22 amines;

basic mono cyclic tertiary amines, stabilized abietylamines, diaminopropanes, dehydroabietylamines, and ethoxylates, salts and adducts thereof.

13. The method of claim 1, wherein said solution cleans said substrate.

14. The method of claim 1, further comprising depositing a resist layer on at least a portion of said film.

15. The method of claim 14, further comprising removing a portion of said resist layer.

16. The method of claim 15, further comprising pattern plating said substrate.

17. The method of claim 1, further comprising contacting said substrate with an acid pickle solution comprising a film forming amine, wherein said contacting is before plating.

18. The method of claim 1, further comprising repeating said coating after said plating.

19. The method of claim 18, further comprising plating the substrate after repeating said coating.

20. The method of claim 1, wherein said plating is performed in said solution.

21. A method of electroplating a substrate comprising:

providing a solution comprising from about 0.0003% to about 30% of a film forming amine and sufficient acid to produce a pH of less than about 6.5, the solution comprising hydrochloric acid;

coating at least a portion of the substrate with the solution, thereby forming a film on the substrate; and

plating the substrate.

22. The method of claim 21, wherein said solution comprises a plurality of acids.

23. The method of claim 21, wherein said plating is performed in said solution.

24. The method of claim 21, wherein said film inhibits oxidation of said substrate.