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Reply To: | TechNet E-Mail Forum. |
Date: | Wed, 9 Aug 2000 10:22:23 +0200 |
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Hi all
I have a case here where I am not sure what I see.
- There are dark spots visible below the solder mask on the surface of the traces on a PCB. I attached 2 Pictures in JPEG that show a view onto the surface of the traces with 10x and 40x magnification.
- In microsections we see clearly a cavity between the traces and the soldermask.
- EDX is hopeless, since the dark layer is so thin that the background covers all but the copper peak.
Before I start to work with TOF SIMS, Spectroscopy and other expensive analysis methods I'd like to ask whether one of you knows what the dark spots are.
Thanks in advance. Have a great day.
Guenter
Guenter Grossmann
Swiss Federal Institute for Materials Testing and Research EMPA
Centre for Reliability
8600 Duebendorf
Switzerland
Phone: xx41 1 823 4279
Fax : xx41 1823 4054
mail: [log in to unmask]
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