Hi,
> I guess two reason. Is it right? Or another problem?
>
> 1). Etch rate is so small that the substrate is not etched.
If u are trying to etch <110> silicon then the rate will be slow. However
its my guess that you are trying on <110> silicon surface, coz you have
just mentioned it in the subject of your mail. The etch rate is dependant
on temperature and concentration of KOH so if you use 10M solution of KOH
and use temp of 75-85 degree centigrade you will have substantial etch
rate. (approx. 1000 A/min) The amout of IPA does not matter. Even trace of
it is sufficient.
> 2). The nature oxide on the substrate is prohibit the
> etching of the substrate.
Oxide does get etched by KOH so that should not be the reason of you not
getting a pattern. Infact since KOH etches oxide ( quite rapidly ~ 500
A/min) a nitride mask is used for patterning when etching by KOH.
If you are interested in knowing the exact recipies and profile and
surface texture that is an outcome of KOH etch on silicon, refer to
Sensors and Actuator part A ( Elsevier Publisher). Unfortunately I do not
remember the volume and page number of the issue, but what I do
remember is that it was sometimes after September98 and before Dec 98 last issue
there is an excellent paper which is source of this information. ( you
would just have to browse in 4 issues.)
Good Luck. Let me know if you were sucessfull.
Regards
Amit Shiwalkar
> Please let me know the problem.
> That is very big problem to me.
> Thank you for reading my mail.
> Sincerely.
> ==================================================
> Fr;} >24B 9+7a E-mail AV http://www.hanmail.net
>
>
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Amit Shiwalkar Dept. Of Bio-Medical Engineering.
3,Vasant, IIT Bombay.
Carter Road, Powai, Bombay-400076
Khar,
Bombay(Mumbai)-400052
INDIA.
Email: amits@cc.iitb.ernet.in
" Reality Is a Figment of IMAGINATION "
----------- Amit Shiwalkar
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