Dear Chris,

Thank you for your suggestion. I'm interested in etching my LTO using HF vapor,
but I can not wait until I buy a system. Could you tell me who commercially
provides the service?

Thanks,

Yu

Dear Yu,

did you ever consider using HF vapor instead of BOE?  We have been using this
method just
recently to make nanobeam cavities and used HF vapor to remove the sacrificial
oxide. The
devices were fabricated on a  SOI substrate (SOITEC Inc.) with a device layer of
220nm and
an insulator layer of 2um. In this case you have almost no problems with the
selectivity
between the oxide and nitrite +  the amount of HF used is minimal. Commercial
systems are
available for comparatively little cost (check ammt.com)

Good luck,
Chris.