Ahmad, in 1969 IBM patented the use of HMDS as a primer. By baking 200 wafers at 150 degrees C then spinning on wet HMDS and spin drying. Then applying resist. This was modified in 1980 by YES by vacuum dehydrating the substrate and using the vacuum to create a vapor of HMDS. Vacuum vapor prime was born and has been used since then as the superior method of creating resist adhesion. We at YES have the ability to prime your wafers send them back and they will survive weeks of outside atmosphere without hurting the adhesion. Please contact me for free tests. Bill Moffat. 925 373 8353 or cell phone 408 590 4577. -----Original Message----- From: mems-talk-bounces+bmoffat=yieldengineering.com@memsnet.org [mailto:mems- talk-bounces+bmoffat=yieldengineering.com@memsnet.org] On Behalf Of Haider, Ahmad M Sent: Monday, January 13, 2014 12:17 PM To: mems-talk@memsnet.org Subject: [mems-talk] Shipley 1827 resist without hmds or p20 primer Hi, I am using Shipley 1827 resist for photolithography. Till now, I always have a pre step in which I spin p20 primer onto the wafer and then I spin the 1827 resist onto the wafer. I am facing certain problems with this. Can I just spin 1827 on a clean wafer directly? Can I get some help with the process parameters? Thanks Ahmad _______________________________________________ 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