>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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>

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

Fraunhofer-Institut fuer Biomedizinische Technik IBMT
Abteilung Sensorsysteme / Mikrosysteme
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Germany
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