Hello David,
     Stain may come from your copper surface condition. If you have a bad
pre-cleaning (Acid clean, soft-etching), it will appear a bad surface after
Electroless/immersion plating. Please try to check your pre-cleaning condition.
Another thing is that if your Electroless Ni rapidly oxidize due to long time
dipping @ water rinse, this you may add an acid rinse after Electroless Ni.

I hope this may help you

Jonathan A. Noquil
R&D
Fairchild semiconductor
Cebu, Phils





David Kim <[log in to unmask]> on 03/17/2000 03:16:23 AM

Please respond to "\"TechNet E-Mail Forum.\" <[log in to unmask]>,        David
      Kim" <[log in to unmask]>

To:   [log in to unmask]
cc:    (bcc: Jonathan A Noquil/Cebu/Fairchild)
Subject:  [TN] stain&gold plating




 I am looking for suggestions on "How to remove a stain on gold surface and
why does a stain happen on gold surface after plating?"
 In electroless Ni/immersion Au plating, I have found many stain problems
after plating. Threre are varied shapes of stains such as a spot, a line,
and an irregulare shpae.
 Anyone who can suggest a better idea?

 thank you!