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| From [log in to unmask] Wed Jan 31 10: |
31:23 1996 |
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Rick
Apart from the obvious causes of shorts, fine shorts which are difficult to see
can be caused by over etching. This leaves overhanging copper which then breaks
away during subsequent brushing prior to solder mask application. These slivers
of copper are almost imposible to detect after solder mask without a current
tracer. Pumice cleaning will only cause this problem in extreme cases of over
etching and is therefore more reliable.
Inner layer shorts are more commonly due to photo tooling or registration errors
unless they are plated and etched (buried vias) in which case the above could
apply.
Good luck
--
Paul Gould
Teknacron Circuits Ltd
EMail [log in to unmask]
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