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Electroless cobalt plating

I am experience particles problems in an electroless cobalt plating solution. It was found cobalt not only deposited on a copper substrate but also formed in the solution and attached on substrate surface. If I want cobalt only deposited on substrate, what should I do ?

TZ

Ting Zhong
- Portland, Oregon
2003

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2003

An electroless plating solution is more accurately called an autocatalytic plating solution, meaning that the deposition of cobalt is catalyzed by the cobalt plated surface. I don't believe that it would be normal for electroless cobalt plating to spontaneously start on a copper surface. Normally you would need to give the copper a spark of charge, or at least place it in contact with a catalytic surface like iron or cobalt before plating would commence. So your concentration of cobalt or reducers might possibly be much too high, expediting spontaneous plate-out.

The thing to do is to buy a commercial electroless cobalt plating solution, not make it from scratch.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

I have searched for a commercial provider of an autocatalytic cobalt solution and have not had much luck. Is there one that you are aware of?

Ryan Turner
- Dallas, Texas
June 12, 2009

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Hi, Ryan. I thought it was commercially available, but I could be wrong. I would suggest checking with Technic, and with the suppliers of electroless nickel processes like Palm International. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
July 27, 2009