I am trying to find a formula for figuring minimum conductor width for foil
thickness.  I have found a reference of 2 times the conductor thickness is
the undercut amount.  I have also looked in the IPC Design Guide and only
found a statement that does not give you a bases from which to work.

"The actual design minimum conductor width will be governed by either the
minimum width that can be successfully produced, based on fabrication yield
considerations, of as required by controlled impedance considerations.  In
both instances, the impact of conductor (foil) thickness must be taken into
account."

Thanks
Dee Stover
National Optical Astronomy Observatories
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