Thank you to everyone who replied to my previous e-mail!
I will be ordering an UV filter this week and will try the same processes I did
before with a filter and see if I will get any good results.
Those 10 um holes I'm making are suppose to go all the way through 10 um thick
layer of SU-8 2010 and stop on the SU-8 layer 2100 (100 um thick). Since I have
already exposed the bottom layer it would be no problem to make these holes open
through 10 um deep. The only problem I have is make these holes nicely open! The
final three layer SU-8 structure will be a mold for PDMS and it is important to
have 10um holes open.
Speaking of using hot plates - I tried that, too, but didn't use slow ramping up
or down during the bakes. I may have to try that.
Thank you again to everyone and if you will have more advice for me I would
greatly appreciate it.

Anna