Hi,

Has anybody seen the Ar plasma cause substantial damage to the etching mask? I
was trying to etch 100nm gold using Ar plasma. I have some indium structures
which was used as the etching mask. However, after etching, the gold layer was
basically removed but I found the indium structure was damaged. The damage looks
like 'volcanic crater' which is randomly distributed on the wafer but with
substantial high density. The size of the 'volcanic crater' is about tens of
micron.

Because indium is very soft metal, I suspect the damage is caused by the dust or
the Au residue. Has anyone came across this kind of situation?

Thanks,
Yingtao