Dear Martin, I had a similar problem few months ago trying to etch FHD silica. Finally, I used a mask of evaporated Cr with photoresist on top and it survived at least 2h in silicon dioxide etchant 4:1. Good luck! Sonia. ***************************************************** Sonia Garcia-Blanco Department of Electronics and Electrical Engineering University of Glasgow Oakfield Ave. G12 8LT Glasgow Phone: Office: (0141) 339 8855 ext 0101 Lab: (0141) 330 6014 Email: sgblanco@elec.gla.ac.uk **************************************************** On Tue, 22 Jan 2002, Marty Patton wrote: > Dear Mems Folks, > I want to etch a thick oxide on silicon. BOE attacks the negative > photoresist. Is there another wet chemistry way? > Thanks for your help. > Marty > > Martin O. Patton > Senior Research Engineer > Essential Research Incorporated > 6410 Eastland Road > Cleveland, Ohio 44142 > www.er.com > (440) 816-9850 > _______________________________________________ > 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.mems-exchange.org/