Hello Peter,

What are you trying to etch?  Aqueous solutions of TMAH (tetramethylammonium
hyroxide) and EDP (ethylene diamine pyrocatechol) also etch silicon
anisotropically, and there's plenty of literature out there on both.  TMAH
is particularly useful because it isn't as toxic as EDP and you generally
don't have metal ion contamination.  Here's an excellent article that covers
almost the whole gamut: Kovacs, Maluf, and Petersen: "Bulk Micromaching of
Silicon," Proceedings of the IEEE, Volume 86, Number 8, August 1988.

Regards,

Brian C. Stahl
Graduate Student Researcher
UCSB Materials Research Laboratory
brian.stahl@gmail.com / bstahl@mrl.ucsb.edu
Cell: (805) 748-5839
Office: MRL 3117A


On Thu, Feb 5, 2009 at 8:28 AM, Fei Wang  wrote:

> you can of course try (110) and (111) silicon wafer
>
> 2009/2/5, KUIJPERS, Peter :
> > Hi all,
> >
> > Is there a recipe for wet anisotropic etching of Si?
> > Now we use KOH on {1,0,0} wafers, resulting in a slope of 54.7°.
> > Maybe another crystal orientation and/or etching agent.
> >
> > Thanks in advance
> >
> > Peter Kuijpers