Hi Tsoll, Thanks for your suggestion. I have tried to peel off the structures after cooling down the substrates below room temp and now their seems to be no problem with peeling up off the PDMS moulds. Thanks to all too for the other suggestions. Debashis On Wed, Dec 15, 2010 at 7:03 AM, Tsoll Doiiuwrote: > I'm gonna suggest that you did not allow PDMS to cool down completely, and > use too high curing temperature for a long time. Usually I use 80C for 20-25 > min in an oven, and than put the sample on a surface with a temperature > below room T for like a 10 min - after that I do not have any tearing of PR