Daxiang:

LPCVD Nitride provides the best masking material I have found for deep KOH
etching. It has very high selectivity to the etch but make sure it is thick
enough to mask any pinholes in the film. 1500 angstroms should work fine. Bob
Henderson

-----Original Message-----
From: D. Zhou 
Subject: [mems-talk] Any metal as KOH masking layer?

I am just wondering if any metal can act as the masking layer( strong enough in
KOH and easy to be removed) for deep KOH etching (say,~600 um deep) at 80
degrees. (It may take about 10 hours to finish the etching process). I tried
NiCr (50 nm) but it could not sustain after 2 hours.