It is difficult to get an oxide layer this thick.  It will enevitably be
compressive.  Thermal oxide would take forever to reach this thickness, even
grown wet.  It is possible to do this in a load-locked PECVD reactor, but even
then you have to have the conditions right, or you will deposit flakes of oxide
from the chamber walls all over your samples.  Try searching for PECVD on an
equipment makers list.  The company I work for (Oxford Instruments Plasma
Technology) has such a process, if you want to try us.

Regards

Martin Walker
P.S. Anyone at MEMS2002 come and say 'hello' at the Oxford Instruments table.
>
> From: "Kishore Sundara Rajan" 
> Date: 11 Jan 2002 03:24:04 -0000
> To: mems-talk@memsnet.org
> Subject: [mems-talk] Sio2 Deposition
>
> Hi,
>
> I am trying to deposit about 50 Microns of Sio2 on Si and want a very
> flat surface profile. Can some one suggest an appropriate method for it?
> Thanking You in advance,
>
> Kishore Sundara Rajan
> *****************************************************************************
> **
>
> Kishore Sundara Rajan
> Graduate Research Assistant
> Institute For
> Micromanufacturing
> Louisiana Tech University
>
> Ph  # (318) 251 - 1786
> Fax #
> (773) 243 - 7948
> *****************************************************************************
> **
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