We have our masks printed on A4 bromide transparencies, then we reduce
that by 20x onto an emulsion-on-glass plate. This gives about 3-5 micron
feature size at the total cost (transparency+mask+chemicals) of about
$30 (AUD) per mask. It's decent system, you can have a set of masks in
three days.

If you were to just use the bromide transparencies as a mask, I think 20
micron lines are possible (aberrations in our reduction process prevent
1 micron lines after a 20x reduction). The contrast ratio of bromide is
excellent, and there are no little 'holes' in the black areas. $8 a
transparency.

Personally, I put 9 masks onto a 5 inch chrome mask and dice them up
with an ordinary glass cutter, with the surface protected with clear
contact (the type you cover books with). We get our chrome masks for
about $450, so this works out to about 50 bucks a mask.
Cost-competitive, and I could fill up the page on the advantages of
using chrome-on-glass over the emulsion method.

Jason Milne
Microelectronics Research Group
The University of Western Australia


-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Ryan Saunders
Sent: Thursday, 14 February 2008 2:09 AM
To: [email protected]
Subject: [mems-talk] Printer for transparency masks?

Hello all,

Our group was thinking of printing our own masks on transparencies
instead
of using expensive chrome-glass masks.

Has anybody had success using printing for creating masks?

If so, what type of printer was used?  and what was your minimum feature
size?

Thanks in advance,

J. Ryan Saunders
PhD Student
Mechanical Engineering
University of Alberta