Lattice dynamics and thermoelectric properties of nanocrystalline silicon-germanium alloys...

The lattice dynamics and thermoelectric properties
of sintered phosphorus-doped nanostructured silicon-
germanium alloys obtained by gas-phase synthesis were
studied. Measurements of the density of phonon states
by inelastic neutron scattering were combined with
measurements of the elastic constants and the low-
temperature heat capacity.
A strong influence of nanostructuring and alloying on
the lattice dynamics was observed. The thermoelectric
transport properties of samples with different doping as
well as samples sintered at different temperature were
characterized between room temperature and 1000C. A
peak figure of merit zT = 0:88 at 900C is observed and
comparatively insensitive to the aforementioned param-
eter variations.