[mems-talk] Honeywell SOG 512B Etching Recipe with LPCVD Silicon Nitride Selectivity (Abdel Moneim Marzouk)

[Abdel Moneim Marzouk]

Hi,

I am currently working on developing a process that involves
Honeywell's Spin-on-Glass (SOG) 512B that is deposited on LPCVD
Silicon Nitride wafers. I am using a RIE dry etch to pattern the SOG,
and apparently my recipe etches the nitride faster than it does the
SOG. The recipe I am using includes CHF3 (40 sccm flow rate), Ar (70
sccm), and CF4 (7sccm).

This recipe etches SOG at a rate of 0.20 microns/min, and nitride at
0.5 microns/min. Since my main concern is etching SOG, and I need the
nitride for insulation puroposes, I was looking for an alternative RIE
etch that would be selective to LPCVD silicon nitride.

I really appreciate your help.

Thanks,
Abdel Moneim Marzouk