I have two ideas here.  One is that boron has a much lower
sputter yield than silicon, so it may take some conditioning
of the target in order to get the stoichiometry that you
are looking for.  The other is that it is not enough that
there be boron, but the boron must be electrically active,
in other words the boron atoms must be in the silicon
lattice, rather than interstitial.

Best regards
mark


M. Pliete wrote:

Dear collegues,

we are trying to sputter Si on a Si nitride membrane with our VARIAN
3180. The silicon target (B doped) has a conductivity / resistance of
1 Ohms cm. The thickness of Si we get is a something between 1-1.5
micrometers. But all the conductivity of the film depsoited has
gone.

Has anyone experience with this?
Is there a way to get around this problem?
Does anyone know that it does not work in principle?

Pressure in ther sputtering machine 4.5 mTorr
We tried different powers starting from 0.3kW to 1kW

Thank you for your comments.
Martin Pliete

m.pliete@pt.fh-gelsenkirchen.de
Martin Pliete
FH Gelsenkirchen
FB Physikalische Technik / Mikrosystemtechnik
Neidenburger Str. 43
Postfach: 45877 Gelsenkirchen
Hausanschrift: 45897 Gelsenkirchen
Phone: ++49 / 209/9596-406
Fax: ++49 / 209/9596-514
e-Mail: map@pt.fh-gelsenkirchen.de