Cr does not form a simple volatile compound, so any significant dry
etching will be from sputtering. Ion milling works (we use it here)
since it is solely sputter etching. If you do not have access to a
miller, a reactive ion etcher with Ar should work. A drawback of sputter
etching is that there is no selectivity, so you will etch into the
substrate after the Cr is gone. Photoresist will serve adequately as a
mask. With only 50 A, you may be able to remove the Cr in a reactive ion
etcher using a reactive gas. Don't be fooled into thinking you are doing
RIE. You will be using the energetic ions to sputter, and any chemistry
that goes on would be incidental. However, a poor choice of reactive gas
can give a compound that is more difficult to sputter than metallic Cr.

[email protected] wrote:
>
> hi,
>   Can someone provide me with a recipe for dry etching of Chromium
> (50 angstrom layer)?
> Thanks,
> Siddharth
>
>

--
Winston Chan                            | phone: (319) 353-2398
Dept. of Electrical Engineering         | fax: (319) 353-1115
University of Iowa                      | email: [email protected]
Iowa City, IA 52242