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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       ._,
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