>I am using cured polyimide (PI 2545) as a sacrificial layer in a process
>to
>create long and wide airbridges.  I have been using hot (110C)
>Ethylenediamine
>to etch the polyimide, but it does not seem to remove all of the
>material
>underneath the bridges.  I have included holes to facilitate the
>diffusion of the
>etchant under the bridges as well as a stirrer, but to no avail.  Does
>anyone
>know of other etchants that could be used to remove the polyimide;
>especially
>underneath the bridges?  By the way, the bridges are made of chrome and
>electroplated gold.  Therefore, the etchants cannot attack these metals.
>
>Thanks,
>
>    Sergio
>
>--
>
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>       ._,
>     ,_| |._/\              Sergio Palma Pacheco
>     |       |o/^^~-._      Radiation Laboratory
>   /-'                | ~   3121 EECS Building
>   \__/|_            /'     University of Michigan
>         \__        | .      Ann Arbor, MI 48109
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>         ~~^\/'              e-mail: pacheco@engin.umich.edu
>
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>
>
>

******************************************************
Dipl.-Ing. Ralf Keller

Fraunhofer-Institut fuer Biomedizinische Technik IBMT
Abteilung Sensorsysteme / Mikrosysteme
Ensheimer Str. 48
66386 St. Ingbert
Germany
Tel.: +49 (0) 6894 / 980-158
Fax: +49 (0) 6894 / 980-400
e-mail: ralfk@ibmt.fhg.de
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