Hi all,

I have a beam structure and would like to release the SAC under the beam. The
beam is 1 micron wide, 100 microns in length and only 0.1 metal film on top of
SIN. The SAC is about 2 microns thick. I plan to use PSG or SOG as SAC. I tried
HF, all metal was gone. I don't have xenon-difluoride dry etch facility. Any
suggestions? please help.

Regards,
Araya