Ken,

I experienced the same problem years ago. We traced the problem at that time to
gold porosity, allowing oxidation of the nickel. I don't recall the fix , but I
think we went to 50 microinches of electroplated Gold.

I dont know if this helps or not, Good Luck.

Les Connally
>  From: Ken Patel <[log in to unmask]>, on 6/24/98 11:54 AM:
>  On my electroless Nickel/immersion gold bare-board, I have seen few places
>  with brown/copper looking surface. I have following questions in this
>  regards.
>
>  (1) Is it due to not having Nickel and gold going directly on the copper
>      pads?
>  (2) What is the reliability risk after the board assembled if above is
>  correct
>      I mean gold going directly on the copper pads?
>  (3) We have specified immersion gold over Nickel. Looking the color which
>      is not 100% copper looking, can immersion gold be plated/applied on
>      copper or may be process might be changed to electrolytic gold?
>
>  re,
>  ken patel
>  ______________________________________________________
>  Ken Patel                       Phone:  (408) 490-6804
>  1708 McCarthy Blvd.             Fax:    (408) 490-6859
>  Milpitas, CA 95035              Beeper: (888) 769-1808
>
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