Hi Giuseppe,

Just a brainstorming idea:
Locally oxidize the Si and etch the SiO:
Protect with SiN, structure SiN, oxidize 70 nm (should be well
controllable), strip SiN, etch SiO.
I never heard of this being done or tried it myself. Am I missing a point
why this cannot work?

Cheers,

Ralf G. Longwitz.

Research Assistant
Microsystems integration group
Swiss Fed. Inst. of Technology
_______________________________

EPFL-DMT-IMS  BM 3.125
CH-1015 Lausanne
http://dmtwww.epfl.ch/~rlongwit
tel: +41.21-693 6727
fax: +41.21-693 5950
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> -----Original Message-----
> From: giuseppe@cumsl.ctr.columbia.edu
> [mailto:giuseppe@cumsl.ctr.columbia.edu]
> Sent: 26 June 2000 21:19
> To: MEMS@ISI.EDU
> Subject: CSE
>
>
> I am looking for a wet chemical etching solution that etches silicon
> isotropically and slowly, I mean its have to be controllable, because I
> have to etch only 70 nm . If anyone out there know of any
> means of doing this, please send me a mail
>
> Thanks,
> Giuseppe