Hello all,

I'm looking at hot embossing/imprinting to produce some simple microfluidics in
plastic films (PET and polycarbonate), and am trying to get a feel for the
capabilities and limitations of the technique, so I'd be very grateful for any
opinions or answers on the questions below...

How much pressure is typically required for plastics like these? The presses
I've looked at (Carver, Jenoptik) seem to have pretty high force ratings
(10-100 kN), but is this just to work with big samples? What I'm hoping here is
that the small samples I want to work with (max. 25mm=1inch diameter) might not
require such a big (and, I assume, correspondingly expensive) press.

The answer to the previous question will probably answer this one - how rigid
do the molds need to be? I found some messages in the archives about using SU-8
on glass as a mold, but nothing conclusive as to whether it worked or not. How
about even softer - e.g. PDMS?

I know that one of the side-effects of the hot embossing process is a thin
residual film around the edges of the mold, but what I don't know is how thick
this is likely to be. I want to imprint channels on both sides of a thick
(approx. 500um) plastic film, so that where the channels cross over each other,
there will be a thin membrane (1-10um thick). Is it likely to be difficult, or
even impossible, to produce this thin membrane? And how repeatable would you
expect this thickness to be?

Best regards,

Ken Healy

Dept. of Electrical and Electronic Engineering
University College Cork, Ireland