for your KOH treatment, i'm not sure if you need to remove any native oxide
before exposing the doped Si to high pH.

On Jan 18, 2008 9:30 AM, Dave Goldstein  wrote:

> Thanks for all your suggestions. My way of telling how much materials have
> been removed is by measuring the sheet rho on the Si. Remember that I have
> a
> diffusion at the surface? I am suspecting that at the very top Si surface
> there are lotta lattice damage by phosphorus precipitates etc so that is
> why
> I try to remove a small amount of material at the top surface.
>
> I have tried very diluted CP etch (HNA=1:10:9) but it always leaves a
> white-ish cloud Si surface. I don't understand why.
> For the room temperature KOH, I leave it in there for 5 minutes but it
> doesn't seem to etch anything. I will do more trials on this. the KOH
> seems
> pretty promising.