I due similiar things with PDMS but have never characteristized the
thickness. I will be doing this today actually, using ellipsometry. I can
not guarantee the range I am spinning will be that thick but I'll send you
what ever data I get.

> I want to spin coat a 500 micron PDMS (Sylgard 184) layer on a Si wafer. I
> have been trying to find any published literature presenting variation in
> PDMS layer thickness with spin speed and spin time, but haven't find any.