High speed method for plating palladium and palladium alloys

Abstract

A high speed method of depositing palladium and palladium alloys is disclosed. The high speed method uses an aqueous, ammonia-based bath which has reduced free ammonia in the bath. The high speed method may be used to deposit palladium and palladium alloy coatings on various substrates such as electrical devices and jewelry.

1 . A method comprising:
 a) providing a composition consisting essentially of one or more sources of palladium, ammonium ions and urea;   b) contacting a substrate with the composition; and   c) generating a current density of at least 10 Amps/dm 2  to deposit palladium on the substrate.   
   
   
       2 . The method of  claim 1 , wherein the current density ranges from 10 Amps/dm 2  to 100 Amps/dm 2 . 
   
   
       3 . The method of  claim 1 , wherein the composition further includes one or more acids or salts thereof. 
   
   
       4 . The method of  claim 1 , wherein the composition further includes one or more brightener. 
   
   
       5 . The method of  claim 1 , wherein the composition has a free ammonia concentration of less than 50 g/L. 
   
   
       6 . A method comprising:
 a) providing a composition consisting essentially of one or more sources of palladium, one or more sources of alloying metals, ammonium ions and urea;   b) contacting a substrate with the composition; and   c) generating a current density of at least 10 Amps/dm 2  to deposit palladium alloy on the substrate.   
   
   
       7 . The method of  claim 6 , wherein the current density ranges from 10 Amps/dm 2  to 100 Amps/dm 2 . 
   
   
       8 . The method of  claim 6 , wherein the composition further includes one or more acids or salts thereof. 
   
   
       9 . The method of  claim 6 , wherein the composition further includes one or more brightener. 
   
   
       10 . The method of  claim 6 , wherein the composition has a free ammonia concentration of less than 50 g/L.