It really depends on the use you want. Why exactly do you need to spin it so
thin, if you need it thicker and so on, because otherwise you can use a
sacrificial layer tha dissolves in water.
Acetone will in fact swell PDMS, and therefore deform it.

>
> On Thu, Jul 9, 2009 at 3:47 PM, Shah, Forum N wrote:
> > Hi,
> >
> > I am spinning PDMS on Si wafer on which the sensors would be fabricated.
> >
> > Can anyone suggest a way to peel off the PDMS layer from the Si wafer  once
the
> > fabrication process is over?
> >
> > When I tried using acetone it rather just removes the PDMS in an irregular
fashion and does
> > not let me peel off the PDMS layer completely keeping it intact.
> >
> > Thanks,
> >
> > Forum