Hi all,
I'm working on a GaAs/AlgaAs heterostructure and I'm using a
solution based on citric acid to achieve good differential etching
between the GaAs and the AlGaAs. Unfortunately the solution I'm using
is not strong enough to attack the semiconductor due to the presence of
oxide. I was wondering then, if someone knew any solution wich attack
native GaAs oxide (probably Ga_2 O_3) and doesn't attack AlGaAs oxide
((AlGa)_2 O_3 or Al_2 O_3).
Thanks you very much for your help
Fabio Altomare

PS Does  anybody have any idea how deep and strong is the oxide formed
after exposing the heterostructure to O2 plasma etching?