***** Unclassified *****

On 11-24 you wrote:
>Lately we received boards from one of our PCB suppliers with gold fingers
>that look "oxydised".
>
>Does anybody know what could be the root cause of gold fingers looking like
>that.  They are dark yellow, sometimes uniform, sometimes stained.
>It comes off when we "erase" them with a white eraser.
>
>Is it a bad rinsing and/or bad drying after plating ?
>Could it be the gold itself that is a poor quality ?
>What would be the impact on functionality ?  Is there any ?
>
>Thanks in advance for any feedback
>
>AL
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Annie,

The problem you described looks a lot like a phenomenon we know as 'burned gold'.
It is usually caused by having the current density (locally) to high in the plating bath. Mostly the surface of 'burned gold' is very rough, but otherwise I do not know of any impact on the functionality, but I am no expert in this field.

Hopes this helped a bit,

Jan

----------------------------------------
Jan Bokhove
Dep. CQM
Hollandse Signaalapparaten
tel. +31 74 2482949
e-mail [log in to unmask]
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