Hello,

 i intend to do contact lithography on a BCB-film (a polymer film) which is
spun on a rectangular glass sample. For the given application i need
resolution which is as high as possible. Unfortunately the resolution is
still unsatifactory. I believe that it is caused by the edge bead of the
BCB-film and the photoresist.  I try to remove the photoresist edge bead by
exposing and developing the edge, using a simple shadow mask. That works
fine when doing lithography on glass only.
I try to remove the bcb edge by etching it, using RIE. I can't measure any
remaining edge bead. Nevertheless the resolution of lithography on BCB films
is much worse than that on glass alone.

Thank you for any comments,
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>      Jan Sundermeyer
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