Hi,

I have a 3000A layer of Si3N4 on a 1000A layer of thermal oxide which itself is
on doped poly silicon, I need to etch some areas of Si3N4 and then some ares of
oxide under that from the opening, I wonder if anybody can suggest a proper
etchant for this thickness of silicon nitride?
I wonder if anybody can help me?

Thanks,


Laleh Rabieirad
PhD Student
ECE Department
Purdue University