I used a perfluoro-silane on my wafer to ensure that the PDMS released
cleanly. I don't recall the exact name of the silane at the moment but it
was vapor deposited in a vacuum desiccator overnight, really easy.

Jonathan Abbott

On Wed, May 25, 2011 at 10:34 PM, Ali M. Koupaei  wrote:

Hello all!

I made PDMS on a patterned silicon master; however after cross-linking at
50oC overnight, the PDMS film cannot be removed from the master uniform and
nicely; in fact the master is gone and PDMS can only be removed partially so
much so no patterned PDMS can be achieved.

Does anyone have any idea how I can solve this problem and what is wrong
with the master? As usual I am using a 10:1 ratio of elastomer to
cross-linker. For another master I do not have the same problem and PDMS
film can be thoroughly removed from the master and nothing remains on
master.

Thanks a lot!

Ali