Thermoelectric power of boron phosphide at high temperatures

A detailed study on the thermoelectric power of boron phosphide crystals is carried out at high temperatures ranging from 300 to 1200 K. The structure and the electrical properties also are studied for specimens of various growth temperatures. The thermoelectric power of boron phosphide is found to be -300 to -500 μV/K for n-type and about +500 μV/K for p-type at 500 K. Ionized impurity scattering and lattice defect scattering are considered to be the dominant mechanism to determine thermoelectric power values. The activation energy of ionized impurity is estimated to be (0.02 +- 0.01) eV and that of lattice defect is found to have activation energies of (0.09 +- 0.02) and (0.2 +- 0.02) eV. (author)