Hello Myung Kwon

I agree with a previous post that using xenon difluoride to etch your Mo would
be an interesting alternative. Note it will etch at about 1/6th the rate of
silicon so you would need to make sure there was no exposed silicon. Which
raises the question, what is under your Mo? If it is silicon the XeF2 will
continue to etch the Si after it is finished with the Mo. If it is just about
anything other than Si it will stop.

If you think you would like to try this we would be willing to run a sample for
you to see how it works. XACTIX is the world wide leader in etching equipment
using xenon difluoride with several models to meet diverse budgets. You can
contact me directly or you can contact  our local agent for support.

Best Regards
David Springer
XACTIX, Inc.
[email protected]
www.xactix.com