Additive for plating bath

Abstract

A plating bath additive and a plating bath using the said additive are provided, which plating bath contains a hydroxyalkanesulfonic acid and which even when applied to an electronic part such as a semiconductor device does not give rise to a problem such as circuit-to-circuit insulation becoming defective. The plating bath additive contains a hydroxyalkanesulfonic acid as a main component and has an alkali metal content of less than 0.05 mass % relative to the hydroxyalkanesulfonic acid. The plating bath incorporates the said additive therein.

1 . A plating bath additive containing a hydroxyalkylkanesulfonic acid as a main component, characterized in that the content of an alkali metal relative to the hydroxyalkylkanesulfonic acid is less than 0.05 mass %.  
     
     
         2 . A plating bath additive as set forth in  claim 1 , wherein the hydroxyalkylkanesulfonic acid is isethionic acid.  
     
     
         3 . A plating bath additive as set forth in  claim 1 , wherein the hydroxyalkylkanesulfonic acid is prepared by oxidizing a hydroxyalkylmercaptan with use of hydrogen peroxide.  
     
     
         4 . A plating bath containing the plating bath additive described in  claim 1 .  
     
     
         5 . A plating bath containing the plating bath additive described in  claim 2 .  
     
     
         6 . A plating bath containing the plating bath additive described in  claim 3 .  
     
     
         7 . A plating bath additive as set forth in  claim 2 , wherein the hydroxyalkylkanesulfonic acid is prepared by oxidizing a hydroxyalkylmercaptan with use of hydrogen peroxide.  
     
     
         8 . A plating bath additive as set forth in  claim 4 , wherein the hydroxyalkylkanesulfonic acid is prepared by oxidizing a hydroxyalkylmercaptan with use of hydrogen peroxide.  
     
     
         9 . A plating bath additive as set forth in  claim 5 , wherein the hydroxyalkylkanesulfonic acid is prepared by oxidizing a hydroxyalkylmercaptan with use of hydrogen peroxide.  
     
     
         10 . A plating bath additive as set forth in  claim 6 , wherein the hydroxyalkylkanesulfonic acid is prepared by oxidizing a hydroxyalkylmercaptan with use of hydrogen peroxide.