Hi,

We pattern Au over Cr (200 A) with subsequent removal of the Cr outside the
Au regions.  We find that the Au features, though usually surviving the Cr
removal etch per se, do fail the 'tape test' post-Cr removal.  These
features survive this test pre-Cr etch and are large enough that we
wouldn't expect an isotropic undercut to cause them to lift-off  We have
tried the commercially available Cr-7 and Cr-14 with the same
results.  Does anyone have any suggestion as to an etchant that maybe more
viscous (as it appears capillary forces etc... may be increasing lateral
etch of the Cr versus vertical)?

Thanks in advance.

Brian Dick
Post-Doc/Research Scientist
BioSecurity and Nanosciences Laboratory
Lawrence Livermore National Lab