Hi:
I am using a photodefinable polyimide (PI2771) from HD
Microsystems.  They have both negative and positive
acting films.  You can also choose from a variety of
etching schemes including one that develops (etches)
in TMAH or a TMAH based developer. I suggest you take
a look at their website:
http://www.hdmicrosystems.com/



=====
Carlton C. Watson, Ph.D.
Microfabrication Manager,
TLC Precision Wafer Technology
1411 West River Road N.
Minneapolis, MN 55411
Ph:  (612) 341-2795
Email: carlton@tlcprecision.com
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