a wet etchant for silicon nitride used quite a bit is hot phosphoric =
acid.=20
usually done in a reflux reactor. it is masked with sio2 and does  bot
etch silicon.

avi


Message: 3
Date: Sat, 19 Nov 2005 17:17:35 -0800
From: "Roger  Brennan" 
Subject: [mems-talk] Wet Etchant for silicon nitride
To: "General MEMS discussion" 
Message-ID: 
Content-Type: text/plain;       charset=3D"iso-8859-1"

Concentrated HF is the only etchant I know that removes silicon nitride
without much damage to silicon.  However conc HF is much too slow.  Is =
there
an etchant that removes nitride quickly but does not harm silicon?