Hi everyone,

I was wondering what is the best way to etch both stoichiometric(Si3N4) and high
concentration silicon Nitride with selectivity to oxide(thermal oxide). I have
been reading the LOCOS process and have come accross Phosphorus solution and so
on but would like to ask some practical experience in etching Nitride with
selectivity to oxide as i have no experience. May be the methods used and the
etch rate between Si3N4 and oxide if any.

Thanks in advance for any help.
Nimo