"I
just wanted to let you know how happy we are with our first
results with Bluefire Police.
...our
objective was to produce 100 micron wide channels in PDMS
(silicone rubber). I started by printing the design onto A0 size
paper using an inkjet printer. I then photographed the print using
an SLR loaded with Bluefire Police 35mm film... and developed it
using the Bluefire Micro developer.
The
next step was to take a silicon wafer and spin coat a UV-curing
epoxy called SU-8 onto it to thickness of about 100 microns. The
developed Bluefire negative is placed on top of the SU-8 and the
whole thing exposed to UV light for a few seconds. The negative is
removed and the SU-8 is placed in a developer which strips away
anywhere that was not exposed to UV light (i.e. the black parts of
the negative or the white paper of the original print). What's
left is our design standing up in relief to a height of 100
microns. ...
(Images
showing a) "cross" are of a junction between four
channels on the structure. Width of the channels is nominally 100
microns...
(Images
showing Vs) are of a small angle structure which was one of
several I included to test the definition of the process. On the
negative the finest ... structure lines are theoretically 10
microns wide...
All
in all we are very pleased with these initial results...
...
normally, instead of 35mm film we use a specially designed mask
etched in thin chromium film on quartz plates. They have to made
"out of house", they cost a small fortune and have to be
ordered weeks in advance... the cost/time savings are an excellent
payoff...
