Hi There -

We're doing some "soft" lithography - i.e. PDMS casts of Si molds.  Up
until now, we've been patterning resist and doing bulk etching of Si to
make our molds.  This works fine, but it's kind of slow for prototyping.
Does anyone know a way to "print" a pattern 10-15 microns high directly
on a smooth substrate?  ("Smooth" is relative; things as rough as a
overhead transparency will probably still work.)  It would be a bonus if
the process allows adjusting the height of the lines.

By the way, laser printers and thermal transfer printers seem to make lines
about 5 microns high.  So if anyone knows a way to make a laser printer
or thermal transfer printer print twice or three times on the same area,
that might be worth a try, too.

I will summarize replies back to the list.

Thanks in advance,

Marc Unger
Caltech Applied Physics
ungerm@cco.caltech.edu