check this paper.

INSTITUTE OF PHYSICS PUBLISHING SMART MATERIALS AND
STRUCTURES
Smart Mater. Struct. 15 (2006) S112–S116
doi:10.1088/0964-1726/15/1/018
Microfluidic channel fabrication by
PDMS-interface bonding


Bala

--- "Peng Li (Paul)"  wrote:

> Dear friends,
>
> I want to spin coat PDMS on glass wafer to get 50um
> thickness layer. Does
> anybody know where can I find data of PDMS thickness
> corresponding to spin
> speed?