Hi Lydia / Allen,

  Your reply to my e-mail was indeed helpful and am thankful to you for that.
However, i'm facing a new problem in trying to get a pattern onto the
photosensitive PDMS. Publications suggest that i use a Mylar foil which keeps
the oxygen out and thus makes sure that cross linking is not affected. The
problem am facing now is, After exposure when I peel off the Mylar film some of
the uv- PDMS is peeled off too. Note that since i'm using a exposure box for the
UV exposure the tool is very hot at the end of a 2 hr exposure. the procedure i
follow is as follows.

  1)      Spin the mixture on to the wafer in a spinner at a spin speed of 4000
rpm for 60 secs
  2)      Do pre-exposure baking for 10 mins at 100 C to drive away the solvents
  3)      Let the wafer cool for 5 mins before covering it up with Mylar film
  4)      Place the wafer wrapped in a Mylar foil in the exposure box and align
the mask on top of the wafer.
  5)      Close the lid and switch on the vacuum.
  6)      Close the box and turn on the UV light for 2 hours. The maximum
exposure for one cycle is 999 secs. So for 2 hours we need to repeat the cycle
for 7.20 cycles.
  7)      After exposure open the lid and turn off the vacuum. The lid would be
hot from exposure and so the wafer and mask might be stuck to it. Let it cool
down for 10 mins before trying to take the wafer out. See to it that the Mylar
film is still on
  8)      Slowly and very carefully try to peel away the Mylar film.
  9)      Do post-exposure baking for 25 mins at 100 C
  10)   Let the wafer cool down for 10 mins
  11)  Hold the wafer by a pair of tweezers and pour drops of xylene  onto it.
When you see the pattern developing stop pouring the xylene and wash away the
remaining Xylene in water.

  Please help me out with any suggestions that you might have. Thank you. I
appreciate your help greatly.

  Vinny