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| From [log in to unmask] Sat Apr 27 15: |
11:16 1996 |
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Sine Cu foil is (reasonably) isotropic and etching is normally done
at +/- 1g the etching process is fairly isotropic so the etchant
undercuts at a similar rate to etching down. A 1oz (~35um) foil will
therfore undercut by >=35um (on each side) so the feature size could
be 70um (3thou/mil) down on the artwork dimension.
David Whalley
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