Hi all.

Anyone out there have to etch indium from the back surface of their GaAs
wafers after MBE growth?

Any thoughts on how I can do it?

Boiling conc HCl seems to do half a job (some kind of rough residual
crud left over), and I can't find a suitable way of protecting the
epitaxial surface.

Yep, I'm asking the growers too!

Many thanks,

Andy