I did some work a few months ago on wet etching polyimide as a release process rather than for patterning. After extensive searching we finally identified an etch which would remove the polyimide. The results were mixed, however, and the etch we found was very aggressive. Careful thought must be given to the other layers on the wafer when using the etch, so it may not suit your needs. Although I haven't given up completely with the wet etch, a dry etch is much easier to control and is more production friendly. There have been postings in the past on dry etching which you can find in the archives. An alternative could be to use a photosensitive polyimide which you can pattern and develop. We have used PI2723 from HD Microsystems for several years and are very happy with the results. ( www..hdmicrosystems.com/conn/offices.html for contact details). If you could give more details of the process you are running I may be able to offer a few tips. Andy Scholes, Ph.D. Utvecklingsingenjör ACREO AB SE 164 40 Kista Sweden >>> shadyar@yahoo.com 04/12/03 03:34am >>> Dear All, Does anybody happen to know about the wet-etching of polyimide? Is there any "standard" etchant to wet-etch polyimide layers? Appreciating any hint, Sh.Farhangfar __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - File online, calculators, forms, and more http://tax.yahoo.com _______________________________________________ MEMS-talk@memsnet.org mailing list: to unsubscribe or change your list options, visit http://mail.mems-exchange.org/mailman/listinfo/mems-talk Hosted by the MEMS Exchange, providers of MEMS processing services. Visit us at http://www.memsnet.org/