Do a Google search for "niobium etch rate mems."
The first paper you'll see has formulation and etch rates for Nb and a bunch
of other metals.
    --Kirt Williams

----- Original Message -----
From: "Sadhana Patil" 
To: 
Sent: Friday, September 21, 2007 6:48 PM
Subject: [mems-talk] Nb wet etching

> Hi all,
> Looking for some help on the kind of wet etchants available for etching
> Nb.
> I have vaguely heard about HF(1):HNO3(1). Does anybody have an idea of
> what is the etch rate of this chemical for Nb? Are there any other
> etchants available for Nb? And does it etch other metals like Au, Fe,
> CuMn, Ni?
> Thanks,
> ES...