Mehmet, we like to think of ourselves as HMDS experts and we are totally confused. Is your process:- 1) Vacuum Vapor Prime at 150 degrees C to give a monolayer of HMDS then apply 10 microns of resist. Then expose and develop. If so your 10 microns of resist is sitting on top of a monolayer of resist and when you expose and develop it should act like a normal resist layer whether you have a monolayer of HMDS at the wafer surface or not. Can you clarify. Is this your process. If so are you soft baking at too high a temperature only when you do HMDS? Bill Moffat CEO YES. -----Original Message----- From: mems-talk-bounces+bmoffat=yieldengineering.com@memsnet.org [mailto:mems- talk-bounces+bmoffat=yieldengineering.com@memsnet.org] On Behalf Of Mehmet Yilmaz Sent: Monday, September 21, 2015 2:25 AM To: General MEMS discussion Subject: [mems-talk] About difficulty in photoresist development (if using HMDS as adhesion layer) Dear mems-talk community, If I use HMDS as adhesion layer, I am having a problem with the development of a photoresist called AZ4562 (about 10 micron thickness). In addition, I am having the same development problem with AZ5214E (about 1.4 micron thickness). If I do not use HMDS, the development time is usually about 60 seconds, or even less. However, if I use HMDS, the development time goes up to 45 minutes (not seconds...) and still the development is not successful, but the resist is completely removed from some parts of the patterned areas on the wafer. Also, I have seen this problem with different substrates such as Silicon, Quartz, and Pyrex. I am wondering what would be the reason for that? Is it possible that HMDS is old, and out of date? Could that explain the problem? Or, do you have any other comments based on your own experience? Could you please comment? I am looking forward to your replies. Thanks in advance, Mehmet Mechanical Engineer _______________________________________________ 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