Another etchant that works well for Ni is Aluminum Etch, which contains
phosphoric and nitric acids.  If you just want to strip the Ni you can
use Piranha.

Roger Shile

-----Original Message-----

Hello everybody,

Does anybody have experience of using Transene nickel etchant (TFB) with
concentrated Nitric acid to etch Nickel on Silicon?

I need to etch Nickel from SOI wafer (220 nm Silicon on top of 1 um
buried
oxide layer), I wonder if nitric acid present in Nickel etchant
will etch Silicon too. At present, I need to soak the sample in nickel
etchant for 10 minutes to remove 25 nm of nickel (slow rate of nickel
removal
due to plasma processing of sample with nickel on it, normally
evaporated
nickel is removed in 2 minutes but after plasma etch, it takes a lot
longer).

--
Ananth Krishnan
Texas, USA