> Does any one like to tell me a typical composition for  EDP,
> operating temperature and the relation between the etch rate and mol
> concentration of each reagent.

See the papers

H. Seidel, L. Csepregi, A. Heuberger, and H. Baumgartel,
"Anisotropic etching of crystalline silicon in alkaline solutions,
I. Orientation dependence and behavior of passivation layers, "
J. Electrochem. Soc., vol. 137, no. 11, pp. 3612-3626, Nov. 1990.

H. Seidel, L. Csepregi, A. Heuberger, and H. Baumgartel,
"Anisotropic etching of crystalline silicon in alkaline solutions,
II. Influence of dopants, "
J. Electrochem. Soc., vol. 137, no. 11, pp. 3626-3632, Nov. 1990.

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Kirt R. Williams, Ph.D.
Research Staff Scientist
Lucas NovaSensor
1055 Mission Ct., Fremont, CA  94539-8203
Kirt_Williams@compuserve.com
(510) 661-6147  FAX (510) 770-0645
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