Q. I operate an electroless copper bath on a plastics line. We have suddenly started experiencing a “mudding out” condition where the copper is plating onto something in solution and falling out. The bath is not overly active with slow initiation and low plating rates. I used some decorative chrome solution in my etch recovery system about a month ago. The chrome was contaminated with drag out from a microcrack nickel bath. Any thoughts on if this is the issue or am I totally missing something? —P.S.
A. My best guess here is that your electroless copper bath is contaminated with material from one of your prior steps. Given the complex chemistry of electroless plating baths, you have probably created an environment in which the copper will plate on one of the contaminants. You might check with your chemical vendor and see if they have a methodology for cleaning up your electroless copper bath. If not, you may have to install a new plating bath and probably the baths used prior to the electroless copper step.