> We are considering the use of Ta for simple coplanar electrode strips (10
> microns wide and 1000 microns long) patterned on quartz wafers, or maybe on
> top of an LTO layer deposited on the quartz.  I imagine we have to
> planarize to put this stuff down on the LTO, but are adhesion promoters
> needed?  Are there any serious pitfalls to avoid in the use of this metal?

Thomas,
there's lots of details, as usual, which depend on the deposition method
you consider. I assume that for an electrode application, film
resistivity will be an issue. alpha- and beta-Ta have widely different
Rs, substrate temperature is the main controlling parameter. You don't
want to work in a region where you deposit a mixture of both phases.

best regards,
klaus
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