The variations of Schottky barrier heights on Si-1-x-y GexCy films wit
h composition and strain have been investigated and compared to those
expected for the band gap energy. The barrier on n-type does not depen
d on composition and strain. This independence suggests that the Fermi
level at the interface between tungsten and Si1-x-yGexCy alloys (x no
t equal 0) is pinned relative to the conduction-band. For Si-1-x Ge-x,
the barrier on p-type follows the same trends as the band gap. For th
e ternary alloys, the variations of the barrier on p-type seem to be t
oo large? to be only due to a variation of the band-gap. In addition,
we have investigated the influence of the deposition conditions of the
sputtered-W-gate on the barrier to silicon and Si1-xGex, Our results
show that the barrier on n-type-Si and p-type-Si1-xGex-films increases
when the stress retained in the W-films changes from compressive to t
ensile as the deposition pressure increases. The absence of change in
the barrier height of W to p-type-silicon and n-type-Si1-xGex-films su
ggests that the Fermi level at the interface with Si is pinned relativ
e to the valence-band while it is pinned relative to the conduction wh
en Ge is added.