Mg2Si1-xGex Solid Solution Semiconductors were prepared in the composition range 0.0 ≤ x ≤ 0.4. At a composition x=0.4, effects of impurities were investigated for dopants of Sb and Ag. Carrier concentrations were controlled up to 1.5×1026 electrons/m3 and 5.5×1025 holes/m3 by doping Sb and Ag, respectively. The thermal conductivity κ was measured at 300 K. By calculating the electronic thermal conductivity κel based on the Fermi integration, the lattice thermal conductivity κph was estimated to be 2.10 Wm-1 K-1. Figure-of-merits Z's of Mg2Si0.6Ge0.4 at 300 K were 0.69×10-3 K-1 for the n-type sample with an electron concentration of 5.4×1025 m-3 (3000 ppmSb) and 0.47×10-3 K-1 for the p-type one with a hole concentration of 5.2×1025 m-3 (16000 ppmAg).
(Received March 24, 1992)
Keywords: dimagnesium silicon germanide, semiconducting solid solution, dopants, thermoelectricity, figure-of-merit, Fermi integral
† This paper was originally published in Japanese in J. Japan Inst. Metals, 53 (1989), 487 and 55 (1991), 893.
†† Graduate Student, Tohoku University. Present address: Mitsui Mining and Smelting Co., Ltd., Ageo 362, Japan.
††† Graduate Student, Tohoku University. Present address: Central Research Laboratory, Matsushita Electric Industrial Co., Ltd., Moriguchi 570, Japan.