Granted Patent B2

US 7,666,471 · App. 11/386,631 · Granted Feb 23, 2010

Abstract

Claims (11)

1. A method for metallizing a substrate comprising polyimide, said method comprising:

(a) contacting the substrate with a surface treatment selected from the group consisting of plasma and corona discharge;

(b) contacting the substrate with an etching solution comprising from about 190 to 385 g/l alkali metal hydroxide and from about 1 to 10 ppm ionic palladium;

(c) contacting the substrate with an activating solution comprising ionic palladium and a chelator wherein the activating solution is alkaline in pH;

(d) contacting the substrate with a reducing agent;

(e) contacting the substrate with an electroless nickel plating bath wherein the electroless nickel plating bath comprises ammonium chloride; and

(f) contacting the substrate with an electroless copper plating bath;

wherein steps (b) and (c) comprise two separate steps with the etching solution and the activating solution being two separate solutions.

2. A method according to claim 1 wherein the activating solution comprises 20 to 100 ppm of ionic palladium.

3. A method according to claim 1 wherein the pH of the activating solution is between about 9.5 and 12.

4. A method according to claim 1 wherein the electroless nickel plating bath comprises from about 6 g/l to about 12 g/l or ammonium chloride.

Assignments (11)