Hi Andrea,

I've achieved mirror-smooth (100) surfaces with 9:1 (25wt% TMAH
solution):IPA.  The etch rate was somewhat slower than 25wt% TMAH solution,
I think in the neighborhood of 30µm/hr at 85°C.  In general it is easy to
control the etch rates of wet etchants by controlling the temperature.  I
don't recall what the RMS roughness was.  There are numerous references in
the literature for this sort of thing.

Good luck,


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 Sat, Feb 6, 2010 at 2:53 AM, Andrea Mazzolari wrote:

> Hi All,
>
> i need to etch (100) silicon at low etch rate (not more than 20um/hour)
> and i need very very low roughness.
>
> I can not use HNA solutions, i can use KOH or TMAH with surfactants.
> Any suggestion about the optimal etching condition for this job ?
>
> Thanks,
> Andrea