Title :
Thermoelectric properties of β-FeSi2 single crystals prepared with 5N source material
Author :
Heinrich, A. ; Behr, G. ; Griessmann, H.
Author_Institution :
Inst. fur Festkorper- und Werkstofforshung, Dresden, Germany
Abstract :
Thermopower and electrical conductivity of undoped β-FeSi2 single crystals have been investigated between 4 K and 350 K in dependence on the deviation from strict stoichiometry within the homogeneity range. The crystals have been prepared by chemical transport reaction in a closed system with iodine as transport agent using high purity source material. Both electrical conductivity and thermopower depend on the composition within the homogeneity range which is explained by different intrinsic defect concentrations at the Si-rich and Fe-rich phase boundaries. Low ohmic material was only obtained by additional doping. At the Si-rich phase boundary the thermopower shows at low temperatures a significant phonon drag contribution with /S/>1000 μV/K
Keywords :
crystal growth from vapour; electrical conductivity; iron compounds; phonon drag; semiconductor growth; semiconductor materials; stoichiometry; thermoelectric power; β-FeSi2 single crystals; 4 to 350 K; 5N source material; Fe-rich phase boundaries; FeSi2; Si-rich phase boundaries; chemical transport reaction; composition; doping; electrical conductivity; homogeneity range; intrinsic defect concentrations; low ohmic material; phonon drag contribution; stoichiometry; thermoelectric properties; thermopower; undoped β-FeSi2 single crystals; Crystalline materials; Crystallization; Crystals; Impurities; Iron; Powders; Semiconductor materials; Silicon; Temperature; Thermoelectricity;
Conference_Titel :
Thermoelectrics, 1997. Proceedings ICT '97. XVI International Conference on
Conference_Location :
Dresden
Print_ISBN :
0-7803-4057-4
DOI :
10.1109/ICT.1997.667128
