If possible try a hi temp oxidation of the nitride, pattern resist, quick boe
etch then etch the nitride.

-----Original Message-----
Date: Wednesday, July 27, 2011 11:31:27 am
To: "jumril yunas" ,"General MEMS discussion" 
From: "Bill Moffat" 
Subject: Re: [mems-talk] Si3N4 etching using H3PO4

Vacuum vapor prime.  I can do free tests.  Bill Moffat