Hi Ed,

    Have tried this myself and have similar problems. Do you use a Ti adhesion
layer beneath the Au? If so the piranha is likely attacking the Ti and lifting
off the Au. We use a lower temperature (60C) variant of piranha called Nanostrip
and I've had Au patterns on pyrex and Si lifted clean off (20nm Ti / 500nm Au,
e-beam deposited without breaking vacuum between the two depositions). I'd
suggest using an oxygen plasma instead, if you can.

Masa






===========================
Hello,

Does anyone have any information on piranah's (30% H2O2 : 70% H2SO4)
effect on a 100nm Au layer on silica. Piranah is volently active, it
completely removes my Au layer, but I have seen in literature it can be
used to clean Au. I am trying to drive off organic contaminants and
make my silica hydrophilic using piranha solution while keeping my Au
layer in some areas.

I appreciate any information, thank you.

Ed Keough
Drexel University
Biomedical Engineering