Thanks a lot for your info. I called AZ. They told me 4620 probably not the
good one for 2 micron feature size. I will try 9260 instead.

Bests,

Yi
----- Original Message -----
From: "Kasman , Elina" 
Subject: RE: [mems-talk] Any one knows how to patten AZ4620 with
high aspectratio?

Do you have the manufacturer's datasheet? If you follow their suggested
recipe closely you have good chances of achieving what you are looking
for. Beware - the holes will end up no square, but with heavily round
edges. Now, getting the AZ4620 to be only 8 microns thick is going to be
a different challenge. I believe it is designed to be around 10 microns.
Watch for good environmental conditions and experiment with exposure
time. Do not over-expose. I also found the manufacturer helpful for
debugging bad litho.