> 1.We have a 3D pattern created on Si. The 3D pattern is
> created in a metal.
> 2.We'd like to transfer the 3D pattern into Si by etching the
> metal AND Si
> (i.e., first the metal is etched, but since it has a varying thickness,
> etching of Si begins thereby transferring the pattern into Si).
>
> Question: can this be done? What process, parameters, etc?
>
> Any preference viz-a-viz the metal (Al, Cu, Ti, etc)?


One option:
Use tungsten as the metal and etch with an SF6 plasma.
Single-crystal silicon will etch about twice as fast as tungsten.
Other metals, for example titanium or molybdenum, should also work,
but I do not yet have relative etch rates.

        --Kirt Williams Agilent Technologies