6533b7d8fe1ef96bd126a248

RESEARCH PRODUCT

Hole localization in thermoelectric half-Heusler (Zr0.5Hf0.5)Co(Sb1−xSn ) thin films

Gerhard JakobSven HeinzBenjamin Balke

subject

010302 applied physicsMaterials scienceCondensed matter physicsDopingMetals and Alloys02 engineering and technologySurfaces and Interfaces021001 nanoscience & nanotechnologyThermoelectric materials01 natural sciencesAcceptorSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsSputteringElectrical resistivity and conductivitySeebeck coefficient0103 physical sciencesThermoelectric effectMaterials ChemistryThin film0210 nano-technology

description

Abstract The (Ti, Zr, Hf)Co(Sb 1 − x Snx) material class has recently come into focus as an attractive p-type high-temperature thermoelectric material. This study experimentally demonstrates that homogeneous, highly textured (Zr0.5Hf0.5)Co(Sb 1 − x Snx) thin films can be grown on single crystalline MgO. By varying the sputter power, samples with both positive and negative Seebeck coefficient can be grown. The underlying reason for the sign change is the segregation of Sn nano-inclusions, which lower the effective doping of the half-Heusler matrix. Similarly the Hall constant also switches sign at low temperatures, which is modeled assuming semi-metal behavior and low temperature hole localization in an acceptor band. Both resistivity and Hall constant are well described by this model.

yearjournalcountryeditionlanguage
2019-12-01Thin Solid Films
https://doi.org/10.1016/j.tsf.2019.137581