Hello being in semiconductor area, you cannot find any 60nm wafers.
The only thing which might be possible is to do an operation which is
backgrinding.

However the process for such a thickness is very difficult.
You might expect heavy mecanical loss.

Sorry to say that.
Please do not hesitate to write if you do intend to pursue.
Regards
Henri

2009/5/28 Andrea Mazzolari 

> Hi All,
> i'm looking for a Silicon wafer supplier who can provide silicon wafers
> with site flatenss of about 60nm over areas of 26x8mm
> Is there any suggestion ?
>
> Thanks,
> Andrea