Hi Kevin, it should be no problem. We use this recipe every day. What happens sometimes is that you burn the resist (you see the non-developed regions opaque) if you are too close to the evaporation source. Of course you should use the AZ as reversal litho to obtain undercut. If you do sputtering, lift-off is much more difficult. Try also hot NMP (80°). I can lift more the 300nm of metal without ultrasonication. Good luck. Daniel * Dr. Daniel Grimm * IFW Dresden * - Institute for Integrative Nanosciences - * E-Mail: d.grimm@ifw-dresden.de * Phone: +49 351 4659-314 * Mobile: +49 177 4926561 -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of Kevin R. Anglin Sent: Montag, 30. November 2009 23:51 To: mems-talk@memsnet.org Subject: [mems-talk] Problems with EOT Liftoff of 1.5 um diameter holes (Au on GaAs) I can't get good EOT liftoff for 1.5 um diameter hole arrays. I'm using PR5214 spun 1.1 um thick, then deposit 50/1000 Angstroms of Ti/Au. I use a supersonic acetone bath to liftoff, but it doesn't. I've tried Chlorobenzene dips post-expose pre-develop, as well as varying baking times and exposure times. Sometimes I liftoff donut shaped patterns instead of holes. Any suggestions would be welcomed, as I continually waste gold.