光交流法によるゼーベック係数の迅速測定 Rapid Measurement of Seebeck Coefficient by an AC Method
An ac method for the measurement of the Seebeck coefficient was developed. Specimens were heated periodically at frequencies in the range 0.2 - 10 Hz using a semiconductor laser. The small temperature increase and the resultant thermoelectric power were measured with a Pt-Pt13%oRh, thermocouple (25 μm in diameter) through a lock-in amplifier. The Seebeck coefficient of a Pt<SUB>90</SUB>Rh<SUB>10</SUB> foil measured by the ac method was in agreement with that obtained from the standard table. The optimum frequency and specimen thickness for the ac method were 0.2 Hz and 0.1 - 0.2 mm, respectively. The Seebeck coefficients of silicon single crystal and several thermoelectric semiconductors (Si<SUB>80</SUB>Ge<SUB>20</SUB>, PbTe, FeSi<SUB>2</SUB>, SiB<SUB>14</SUB>) measured by the ac method agreed with those measured by a conventional dc method in the temperature range between room temperature and 1200 K. The time needed for each measurement was less than a few tens of minutes, significantly shorter than that for a conventional dc method.
粉体および粉末冶金 44(1), 65-69, 1997-01-15
Japan Society of Powder and Powder Metallurgy