Technet guru's

        We have been chasing a nagging process optimization problem regarding
fusion bonded teflon and epoxy hybrid circuit ICDs. We experience a very
small, but consistent lot fallout.  Although the fallout is small, these
materials are extremely costly and even small fallout gets immediate
attention.  The laminated packages go through modified drilling process
designed to accommodate the unlike materials, plasma, direct plating, and
acid copper plating.  The typical defect is a marked ICD where no
noticeable line definition between the post and the hole plating should be
seen because of the direct plating process. The package does not fail ET
and the icd shows no separation.  Typically the drilling and plasma
operations take the lion's share of the blame. For this reason most testing
has been concentrated in these areas. The materials area seems to be black
hole of information as the materials manufacturers tend to be able to
produce information on processing the individual products but cannot help
with composites of the two materials.  Continued testing in the mechanical
areas has been expensive and is beginning to produce diminishing returns.
For these reasons I am seeking two things:

1)  Does anybody have any experience, or information sources with the above
mentioned processes they care to share.  I am particularly seeking
information on the uniformity of the Teflon and Ceramic loaded teflon
materials. Drilling experiences with dissimilar materials.  Experience with
direct plating ICD failure.  Any technical references would be greatly
appreciated

2) Are other people producing this type of product with consistently
satisfactory yields?  Please respond to this offline.  I realize this is
sensitive information.  I am looking for general ballparks, not specifics,
to gauge where we are.

Thank in advance for any responses

Dennis Gagne

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