Dear Li,

Try contacting AMMT (Address below) in Germany.  They have designed various
size's of wafer holder to accomodate single side etching.

AMMT Advanced Micromachining Tools GmbH
Anselm-Feuerbach-Str. 6
D-67227 Frankenthal
Germany

Telephone: +49-6233-49600-14
Telefax: +49-6233-4362-14
eMail: info@ammt.de


Regards
Dr Anil Patel

BAE SYSTEMS Infra-Red Ltd
Caswell, Towcester
Northants
NN12 8FH
UK
Phone +44 1327 356331
Fax     +44 1327 356422
Email:anil.patel@baesystems.com

-----Original Message-----
From: Li Song [mailto:amonnxy@yahoo.com]
Sent: 08 May 2001 09:51
To: MEMS@ISI.EDU
Subject: how to passivate Si wafer( one side) in 600C KOH?


Dear friends,

I am fabricating gas sensor by using SOI wafer.
Because not having suitable chuck for one side
etching, I try to passivate one side, then put whole
wafer in KOH. Considering etch rate for room temp., I
should use 600C  KOH, please recommend one suitable
passivation chemicals.

Thanks a lot.

Sincerely yours

Li Song


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