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.

Good luck!
Elina

-----Original Message-----
From: Yi Zhao
Subject: [mems-talk] Any one knows how to patten AZ4620 with high
aspectratio?

I want to pattern 2 micron holes array (center to center distance for
neighboring holes is 4 micron) on 8 micron thick AZ4620. I prefer a near
vertical sidewall profile of the resist. Does any one has experience on
it, or any suggestion? Thanks,