Abstract
The key to improving the thermoelectric figure of merit of Si-Ge sytem is to reduce the thermal conductivity. Alloy powder with grain size of 20-30nm was prepared by mechanical alloying. The amounts of boron was varied to achieve optimum carrier concentration. The thermoelectric properties of the hot-pressed Si-Ge alloys were measured in the temperature range from 300 K to 1073 K.
The sintered Si-Ge compact was found to have a fine grain structure of about 200 nm. As a consequence, a reduction in thermal conductivity of up to 30% was achieved compared to conventional p-type alloy. A maximum figure of merit of 9×10-4K-1was obtained at 1073K.
