Hi, We've also seen issues with this when dicing sapphire wafers. I usually strip the resist with the chip upside-down, which works most of the time. An alternative used in our lab is a two layer resist, first PMMA 950K, then standard positive photoresist. After dicing, the photo resist is stripped with developer, ideally stirring the chips upside down, which removes most particles. The pmma layer is then removed using acetone, which also removes the remaining particles. Beware of pmma residue though. Hope this helps, Gabriel Quantum Device Lab, ETHZ -----Original Message----- From: mems-talk-bounces+gabriepu=phys.ethz.ch@memsnet.org [mailto:mems-talk-bounces+gabriepu=phys.ethz.ch@memsnet.org] On Behalf Of ProtoSi Info Sent: Tuesday, July 24, 2012 9:22 PM To: mems-talk@memsnet.org Subject: [mems-talk] dicing particle contamination Hello We've been struggling with particles getting embedded in our delicate silicon comb structures during dicing. Our current process involves spraying on a 10um thick layer of photoresist over the entire wafer and then do a soft bake. After dicing we rinse the wafer to remove particles before stripping off the resist. However we're still getting particles stuck in-between the comb fingers. We've attempted ultrasonic cleaning but that damages the combs. Any tips to remove or prevent particles would be greatly appreciated. Thank you Kevin Chang ProtoSi _______________________________________________ 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 _______________________________________________ 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