Specific Process Knowledge/Etch/Etching of Silicon Oxide/SiO2 etch using ASE/ICP recipe for SiO2

This recipe was taken from the ICP Metal etch, with a slight difference in the platen temperature.

Parameter	Recipe name: SiO2_ICP
Coil Power [W]	150
Platen Power [W]	25
Platen temperature [oC]	20
C4F8 flow [sccm]	36
H2 flow [sccm]	13
He flow [sccm]	0
Pressure [mTorr]	2.5

Results when etching a piece of wafer on a Si carrier

Material to be etched	Recipe: 1SiO2_02 *This recipe is no longer stable.	Recipe: 1SiO2_03	Testing other settings to increase etch rate in nitride
Etch rate in SiO2	22.1 nm/min	26.8 nm/min	?
Etch rate in PECVD nitride	.	20.8nm/min (kabi@nanolab 20190301) - ~0nm/min (ecsj@nanolab 20210729)	?
Etch rate in LPCVD nitride	.	only around 6 nm/min (20190820)	23.7 nm/min in the middle, 17 nm/min close to the edge
Etch rate in resist (MIR)	12.5 nm/min	13.9 nm/min	Not tested properly (still more than 1 µm left (1.5µm MIR) after 12 min
Selectivity (SiO2:resist)	1.8	1.9	?
Etch rate in silicon		4 nm/min in the middle of the wafer (80% load) bghe@Nanolab 20190117 2-3 nm/min at the edge of the wafer (80% load) bghe@Nanolab 20190117
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Results when etching a whole wafer on an Al carrier

Material to be etched	Recipe: SiO2_ICP
Etch rate in SiO2	22.1 nm/min
Etch rate in resist (MIR)	16.6 nm/min
Selectivity (SiO2:resist)	1.3
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Material to be etched	Recipe: SIO2_ICP	Testing othe etch rate in nitride
Etch rate in SiO2	22.1 nm/min	?
Etch rate in PECVD nitride	.	20.8nm/min (kabi@nanolab 20190301) - ~0nm/min (ecsj@nanolab 20210729)
Etch rate in LPCVD nitride	.	23.7 nm/min in the middle, 17 nm/min close to the edge
Etch rate in resist (MIR)	12.5 nm/min	13.9 nm/min
Selectivity (SiO2:resist)	1.8	1.9
Etch rate in silicon		4 nm/min in the middle of the wafer (80% load) bghe@Nanolab 20190117 2-3 nm/min at the edge of the wafer (80% load) bghe@Nanolab 20190117
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