Thermal characterization of IV-VI superlattice MBE films

We report on the growth and the structural and thermoelectric characterisation of new superlattice (SL) structures (PbSe_0.78Te_0.22/PbSe_0.76Te_0.24 ) with periods between 1.5nm and 15nm. The structural (SEM-, EDX- and XRD-analysis) and in particular on thermoelectric properties (Seebeck coefficient and Hall-effect measurements for carrier concentration, conductivity and mobility) of molecular beam epitaxy grown thin films based on PbSe_0.78Te_0.22/PbSe_0.76Te_0.24 superlattice structures, grown without additional doping. These SL-structures were grown and analysed as the reduction of the thermal conductivity is of special interest in thermoelectric materials because of the possibility to achieve a high figure of merit. Special care was taken on the in-plane (Volklein method [Volklein, et al., 1987]) and on the cross-plane (3omega-method [Cahill, -]) measurements of thermal conductivity of thin films