Keith,
STS now has a thick SiO2 etcher that is supposedly able to produce aspect
ratios of 10:1 for up to 100 um depths.  We have sent wafers to them in the
past for processing, but do not yet have results from this particular etcher.

Check out http://www.stsystems.com/AOEarticle.html .

-Steven


At 02:22 PM 5/16/00 , Keith Jackson wrote:
>To group
>I was wondering if there were any commercial services which could
>anisotropically etch thick SiO2. The thickness of SiO2 varies from 30  to 60
>microns and is deposited on an Silicon substrate. The need is for prototype
>services on say ten, 4 and 6 inch wafers. If successful there would be a
>need to scale up the process to production levels.
>--
>Keith Jackson
>Lawrence Berkeley National Laboratory
>Berkeley, Ca 94720
>510-486-6894 voice
>510-486-4955 fax
>
>
>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Steven F. Nagle
Ph.D. Candidate                 http://www-mtl.mit.edu/~middle/
Room 10-007                                  middle@mtl.mit.edu
Massachusetts Institute of Technology         Tel: 617-253-2011
77 Massachusetts Avenue                       Fax: 707-215-2906
Cambridge, MA 02139
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     "Stanley looked quite bored and somewhat detached,
                but then penguins often do."


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