Dear David,
Thanks for the info..unfortunately, I have already tried hot (85'C)
un-diluted aqua regia and even after dipping my sample in it for 30
mins, I could still see the shiny iridium on top..I only have 15nm of Ir
on Si substrate and 30 mins should be enough if there was a decent etch
rate..
Have you ever tried to etch Ir?

Regards,
Mantavya

-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of David Nemeth
Sent: 29 January 2007 09:12 PM
To: 'General MEMS discussion'
Subject: RE: [mems-talk] wet etch recipe for Iridium (Ir)


According to the Handbook of Metal Etchants (isbn 0-8493-3623-6,
EXCELLENT resource), hot aqua regia (3 parts HCL, 1 part HNO3) non
diluted is the only wet etchant for iridium known.  They mention it
etches very slowly.

David Nemeth