You should be able to etch Ti on Nitride, the HF etch rate of Nitride in 10% HF
should be very low and 1000A of Ti will etch in 40 seconds. The mixture of
NH4OH:H2O2:H2O (1:1:5) will etch Ti very fast and it will not etch Nitride at
all. However, resist will not stand up to the mixture.

Rick Morrison
Senior Member Technical  Staff
Acting Group Leader Mems Fabrication
Draper Laboratory
555 Technology Square
Cambridge, MA  02139

617-258-3420



-----Original Message-----
From: mems-talk-bounces+rmorrison=draper.com@memsnet.org [mailto:mems-talk-
bounces+rmorrison=draper.com@memsnet.org] On Behalf Of PAULTRE Jacques-Edmond
Sent: Tuesday, June 07, 2011 4:31 PM
To: 'mems-talk@memsnet.org'
Subject: [mems-talk] Ti wet etch with selectivity to Si3N4

Hi,

I need to wet etch Ti patterns deposited on Si3N4.
Typically we used HF for Ti wet etch, but this will not work because Si3N4 will
be etch too.

Do you know the effect of   NH4OH:H2O2:H2O (1:1:5) on Si3N4 ?

Jack Pautre