OK, Steve.
One thing that I have seen with double treat is that the zinc treatment on
the dendrites apparently is thicker than with single treat foil, and when
processing through the e'less copper process the inner layer copper is
etched back and the zinc "tails" remain.  These can give the appearance
of a defect.  This is only seen with non-catalyzed peroxy-sulfuric or with
persulfate etches (I haven't seen too many other types of microetches
used); catalyzed peroxy-sulfurics seem to etch away the zinc tails pretty
well.
I would assume that you know most of the potential reasons for having
ICDs (if you want to discuss it, let me know and we'll run through the list).

Fred J.

>>> Steves <[log in to unmask]> 12/17/97 06:43am >>>
Fred J.:

     I am talking about electroless copper and seperation between the
electroless and the innerlayer copper.

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