Here are my thoughts,

For such an etch I would use one of the AZ series of photoresists. I use
AZ4562 and get selectivities in the range from 50-80:1 and an etch rate
of 4 um/min. Obviously the etch rate depends on your process parameters
as well as etch area etc.. If your institute already has a DRIE Bosch
tool then they should have a process for fast, deep silicon etching.

AZ5462 data sheets can be obtained from your local resist supplier and
are extremely detailed.

What is your minimum feature size? Is the etch profile important? How
accurately do you need to etch - i.e. is 101 um acceptable? These are
all questions you must consider.

If you need further assistance let me know.

Good luck,

James

Vijay Rajaraman - EWI wrote:
> Hi All,
>
> I want to etch 100 microns of Si using Bosch DRIE and I'm unable to use
> some well known masking materials such as SiO2/ Al/Al2O3 for specific
> reasons.
>
> So has anyone tried some other masking material than the above with
> reasonable selectivity? For instance, I could think of a spin-on
> material such as resist or SOG ?
>
> Please share your experiences, either in the forum or in person (by
> e-mail). Any tip(s)/suggestion(s) are appreciated.
>
> Thanks,
> Vijay

--
Dr. James Paul Grant
Postdoctoral Research Associate
Microsystems Technology Group
76 Oakfield Avenue Room 3
University of Glasgow
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