It's rather difficult to bond cured PDMS to other surfaces including itself. Even plasma (corona) is not strong enough to activate various PDMS and hence not the universal solution. Two years ago I was suggested by Dow Corning to apply a thin film of Dow Corning 1200 primer before or after the plasma treatment. However, I didn't tried it yet. I recommend you visit their website (http://www.dowcorning.com/) and ask the experts. Good luck. Chengxun -----Original Message----- From: Vishwanath [mailto:dagarshali@excite.com] Sent: Friday, December 05, 2003 18:45 To: mems-talk@memsnet.org Subject: [mems-talk] Reg: Bonding of PDMS layer Hi,I am trying to fabricate microchannel with some microstructures in it. I use PDMS to make the channel. Its made of two layers. First layer: consists the microstructures. you can image non-circular(square) cylinders rising from the surface of PDMS as the microstructures. Second layer: Is just a U channel which sits right on top of the first layer, there by giving rise to a micro channel with microstructures. Earlier we did not have structures, as a result of this, there was lot of pdms surface available for bonding. We use plasma treatment to bond them. A student taught me and I am following it blindly. I would appreciate if you could send me links to some sites which might describe this process in detail. And also, I would like to know if there are other ways of bonding PDMS surfaces to over come the problem that I have mentioned above. Thanks a bunch,Vishwa _______________________________________________ Join Excite! - http://www.excite.com The most personalized portal on the Web!