A mixture of H2SO4 and H2O2 at a temperature of ~180celsius can remove the resist...This solution is used the remove resist when making glass mask...I am sure it can remove this resist to.....i hope this information helps, Nimo ________________________________ From: ameya gTo: mems-talk@memsnet.org Sent: Wed, June 23, 2010 1:18:23 AM Subject: [mems-talk] Removing hard-baked photoresist Hi I have a combination of PMMA and photoresist AZ3312 on an oxide substrate that was hard baked to 170 C for 2 minutes. The film appears shattered like a piece of glass and the thickness is anywhere from 0.01-0.1 um. The resist is really stubborn and has not yielded to any of the following methods so far - - Microstrip 2001 at 70 C for 1 hour - Asher at 200W for 4 hours - Piranha clean at 100 C for 3 hours - AZ 300MIF developer for 1 hour - Acetone at ambient for 1 day - Acetone at 50 C in Ultrasonic bath for 3 hours - Nano-remover PG at 80 C for 3 hours - Nano-remover PG at ambient for 4 days - Nano-remover PG at 50 C in Ultrasonic bath for 1 hour Has anyone ever had to deal with the removal of extremely hard baked photoresist? Any suggestions will be greatly appreciated! Thanks, -Ameya _______________________________________________ Hosted by the MEMS and Nanotechnology Exchange, the country's leading provider of MEMS and Nanotechnology design and fabrication services. Visit us at http://www.mems-exchange.org Want to advertise to this community? See http://www.memsnet.org To unsubscribe: http://mail.mems-exchange.org/mailman/listinfo/mems-talk