We are producing a structure by through wafer etching to a silicon nitride
membrane. Normally we would use KOH to do this however the structures on the
other side of the wafer are proving to be incompatible with the etch. We have
tried using single sided etching but without high enough success.
1.) Is it possible, using the right chemistry, to RIE etch through a silicon
wafer and stop at the silicon nitride membrane?
2.) Is anyone able to offer this as a service on a small (less than 10) number
of wafers, with a rapid turn around?
Thanks for your help.

Chris Turner
Principal Research Engineer
Central Research Labs
Dawley Road
Hayes
Middlesex
UB3 1HH
UK
tel. +44 (0)181 848 6465
fax. +44 (0)181 848 6442
e:mail  cturner@crl.co.uk
web     www.crl.co.uk