Sebastian, For peeling off PDMS conveniently, silanize the silicon wafer surface that has SU-8 patterns. This can be done by keeping the wafer in a vacuum dessicator along with about 50 microliters of (3-Aminopropyl) triethoxysilane (also called as 3-APTES) for at least 3 hours. The vapours of 3-APTES forms a layer of silane on the surface of the wafer that ensures smooth peeling of PDMS after curing. Good luck! -------------------------------------------------------------------- Bhuvaneshwari K Research Scholar c/o Professor Soumyo Mukherji Biosensors and Bioinstrumentation Group Department of Biosciences and Bioengineering Indian Institute of Technology, Bombay Powai, Mumbai, India. Mobile Number : +91 99 8767 9533. Email : bhuvana.k@iitb.ac.in; larabhu@gmail.com -------------------------------------------------------------------- On 25 February 2014 09:01, Sajeesh Pwrote: > Apply some HMDS coating over the silicon wafer befor spinning the SU8.HMDS > will improve the adhision between Su8 and Silicon > > > On Mon, Feb 24, 2014 at 8:08 AM, Sebastian R Freeman < > sfreema1@binghamton.edu> wrote: > > > Hello everyone, > > > > I am a graduate student making microfluidic devices for the first time. I > > am processing SU-8 2050 negative photoresist on a silicon wafer to try > and > > produce a porous PDMS membrane. My difficulty lies in producing the the > > SU-8 structures. I have been having adhesion problems, as well as getting > > my structures to develop uniformly. The pattern I am trying to make is > > composed of an array of tiny cylindrical posts 50 micros high, with a > > diameter of approximately 5 microns, and spaced 15 microns apart from > each > > other. > > > > The PDMS spin coating is also creating difficulties. When I attempt to > peel > > off the PDMS from the SU-8, the PDMS rips off my posts. I have applied > > Sigmacote as I was told this would lessen the adhesion between PDMS and > > SU-8, but it appears to have only helped minimally. > > > > If anyone has any good advice or suggestions of new approaches, I would > be > > most appreciative. Thank you. > > _______________________________________________ > > 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 > > > > > > -- > Sajeesh P > Research Scholar > HTML Lab > Mechanical Engineering Dept > IIT Madras > _______________________________________________ > 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