Hi!!! All

I want help of urs.I am making cantilever and want to study properties of
it by applying potential accross it.
For these i m taking P- P+ wafer means i m taking P- at from side and
backside is P+ which I want to use as ecth stop while ecthing of P- for
freeing beams.
First of all I grow oxide on P- and over that i did Aluminium
deposition.Than I m doing lithography for getting beams pattern on
Aluminuim.This  oxide and Aluminium moth  will work as mask as well as
beam.Metal deposition i m doing so that i can apply force and will
study its behavior.
After getting patterns on Aluminium film i m able to etch Alumium .
But my problem begins now As I wanted to remove oxide so that my Silicon
can be exposed and Aluminium should be there .
As first i use BHF it was attacking photoresist and than Alumium was also
ecthed out .I have tried after changing ratio of ammonium floride and
Hf.But still it doesn't solve.
So I need ur help if any one can help me.
Hope for tyhe prompt reply.
Saroj
Physics Dept
IISC ,Bangalore