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Both RIE's (RIE1 and RIE2) for silicon based etching have been decommissioned

This information is save because it might be valuable as inspiration for other dry etch systems.

For a general introduction to RIE at DTU Nanolab see RIE (Reactive Ion Etch)

Etching of silicon nitride using RIE can be done with several recipes. It can be etched by our standard silicon etch recipe: OH_PolyA which is based on SF6. It can also be etched using the recipe 1Nitride which is based on CHF3. The difference of these two etches has not been investigate in details. Look in the table below to see what we know

Some RIE recipes for etching of silicon nitride:

Name	SF6 flow	O2 flow	CHF3 flow	N2 flow	Pressure	Power
OH_PolyA	32 sccm	8 sccm	.	.	80 mTorr	30 W
BGE-NITR	.	.	8 sccm	43 sccm	38 mTorr	50 W

Expected result using the above RIE recipes for etching of silicon nitride:

You should be aware that the result can deviate quit a lot from what is written here depending on ex. the mask loading.

Name	Tested with mask load:	Etch rate	Anisotropy	Selectivity to nitride:resist	Selectivity to nitride:oxide	Selectivity to nitride:silicon	Comments
OH_PolyA	10-20%	0.05 µm/min (tested before 2014)	?	~1:1	~2-3:1	~1:13	.
BGE-NITR	10-20%	0.04 µm/min (tested before 2014)	Expected to be very anisotropic - not verified	?	~1:1	~1:1	Especially good to remove nitride on one side of the wafer avoiding getting anything etched on the back side.