Laser cutting of wafers

Hi all,
I have some 150 mm SOI wafers that I want to send out for laser-cutting
down to 100 mm. So far from talking to people, I know that Silicon Quest
and Ultrasil are a couple of places that will do it. However, it seems
that some of these places use resist/tape to protect the surface of the
wafers which can leave residue later even after cleaning. I would like
to keep the surface of my wafers as clean as possible. Does anybody have
sort of experience with the above problem? Also, does anybody have any
recommendations for which place is preferable?
Thanks in advance for all suggestions
-Shrestha