Mike

The use of nitride as an etch stop is not a typical scenario.
Nitride layers can be quite thin, and with nitride having a similar
selectivity to photoresist, a thin layer is unlikely to survive the DRIE
processing.
But as you have now found, with the photoresist-like selectivity and a
thicker layer of material, nitride can indeed work as a stop layer.
If you need any further process assistance with regard to the issues you
are currently seeing, which can be addressed in the DRIE, do not hesitate
to contact the ASE Technical Support Specialist at STS.

Regards

Rich Barnett


Richard Barnett BEng(Hons) MIEE
Product Marketing Engineer (MEMS)
Surface Technology Systems plc
Imperial Park
Newport  NP10 8UJ
Wales  UK

Tel +44 (0) 1633 652400
Fax +44 (0) 1633 652405

email  richard_barnett@stsystems.co.uk
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