Abstract
PbTe sintered materials and metal electrode-semiconductor joints were prepared by plasma-activated sintering (PAS). The undoped PbTe powder (particle size of -1mm) was used for p-type as the source material, while a mixture of 4000 molppm PbI2 (dopant) with the undoped powder for n-type. The large carrier concentration and low mobility resulted for the p-type sintered material, compared with data for the melt-grown undoped PbTe. As for the n-type, the carrier concentration was not fully controlled and the Hall mobility was less than those of melt grown crystals, which indicates that sintering period might be too short to assure a uniformity of doping. The sintering of the semiconductor powder and the joining of metal electrode-semiconductor were simultaneously made in the single PAS process. The Fe/SnTe/p-PbTe and Fe/n-PbTe joints were successful made from the inspections by optical microscope and electric potential measurements, which will lead us to conform a π-shaped thermoelectric device.
