Can someone suggest me a metal to use for masking GaAs/AlGaAs layers in a
Br-IBAE (Bromine,Ion beam assisted etching) machine. I tried using titanium
400angstrom layer, but that etched away. I have read in a few papers that
nickle or chromium could be used. Can some one please suggest if thats
right, I have to use HF on the sample later, so an HF resistant metal is
desired.

regards
Vaibhav Mathur
Graduate Student
University of Massachusetts,lowell