Dear All,

I am trying to purchase silicic acid for TMAH
anisotropic etching of silicon(without atttacking Al).

I was going through the catalog of sigma-aldrich
chemicals and could find silicic acids with various
mesh sizes(from 35 microns-200 micros).The formula for
above Silicic acid is H2Sio3

URL:

http://www.sigmaaldrich.com/cgi-
bin/hsrun/Distributed/HahtShop/HAHTShop.htx;start=HS_CatalogSearch

I have also find silicic acid hydrate Sio2.

Can somebody suggest me which is the best silicic acid
to be purchased for TMAH etching of Anisotropic
etching of silicon.

Thanks
Kris

__________________________________
Do you Yahoo!?
Yahoo! SiteBuilder - Free, easy-to-use web site design software
http://sitebuilder.yahoo.com