Sensitive 3-omega measurements on epitaxial thermoelectric thin films

Here we present a work on the development of a sensitive 3-omega instrumentation adapted for the measurement of the thermal conductivity of epitaxial thin films. The experimental setup has been validated by the measurements on an epitaxial germanium nanostructured thin film. This manganese doped germanium matrix contains Ge3Mn5 nanoinclusions having a diameter of 5 to 50 nm, grown by Molecular Beam Epitaxy (MBE). The 3 omega measurements have revealed that the thermal conductivity of GeMn nanostructured thin films can be decreased by a factor of ten as compared to the bulk value.