[mems-talk] Polyimide wet etching

[Alter]

I want to try wet etching of Polyimide and I am looking for feedback 
regarding limitations of this method. Is it possible to control the 
angle of sidewalls in wet-etched channels? I would like to have vertical 
walls but I am not sure which etchant (if any) could do this. Is there a 
limitation on the width/depth ratio of the wet-etched channel? Ideally 
I'd love to have a channel with the square cross-section (1:1 ratio).
I would be grateful for any tips and hints on Polyimide wet etching you 
could give me.

Thanks
Alex