'Perhaps, some nice parameters (etching pressure and time cycle) can improve the
selectivity
(Si3N4 / Si) ?'
In our experiments, the follwing parameters are employed for protecting the
LPCVD Si3N4 film:
Etching Time Per Cycle: 60s/C, XeF2 pressure: 2-4Torr, N2: 60Torr.

Best regards!
Xu Yan
______________
State Key Lab of Transducer Technology,
Shanghai Institute of Microsystem and Information Technology,
Chinese Academy of Sciences
865 Changning Road, Shanghai 200050, China
Tel: +86-21-62511070 ext.8227 FAX: +86-21-62513510
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