Hi Ramesh

If you would prefer a dry release etch for your cantilevers you might want to
consider using xenon difluoride (XeF2) gas to etch away the silicon under your
cantilevers. XeF2 has very high selectivity to almost all materials including
most metals.

If you would like to discuss this more or try it out please contact me.

Regards
David Springer
XACTIX, Inc.