13:00 〜 13:15
▲ [8p-Z22-1] High thermoelectric performance of Si-Ge alloy by modifying the electronic structure
キーワード：Si-Ge, ball milling, thermoelectric property
In order to improve the figure of merit ZT, many strategies have been reported. For example, the nano-structuring and modulation doping approach has been utilized to improve the thermoelectric properties of Si-Ge alloy by decreasing thermal conductivity without degrading the power factor.
Our previous studies revealed that the B-doped Si-Ge-Au thin film and bulk sample possessed a ZT value of 1.38 and 1.63 at 1000K. We found that the electron transport properties were constructively improved using Au-doping to form an impurity state near the valence band top, and B-doping to control the Fermi level. Very small thermal conductivity ~ 1.5 Wm-1K-1 was obtained due to nanograins. However, Au is an expensive element, and more than ZT = 1.63 is required for improving efficiency. In the present study, we synthesized bulk noncrystalline B-doped Si-Ge alloy with other metal substitution, which is a cheap and non-toxic element. Thermoelectric properties (TE) of bulk nanocrystalline samples were investigated as a function of temperature 300 – 1000 K, respectively.
Our previous studies revealed that the B-doped Si-Ge-Au thin film and bulk sample possessed a ZT value of 1.38 and 1.63 at 1000K. We found that the electron transport properties were constructively improved using Au-doping to form an impurity state near the valence band top, and B-doping to control the Fermi level. Very small thermal conductivity ~ 1.5 Wm-1K-1 was obtained due to nanograins. However, Au is an expensive element, and more than ZT = 1.63 is required for improving efficiency. In the present study, we synthesized bulk noncrystalline B-doped Si-Ge alloy with other metal substitution, which is a cheap and non-toxic element. Thermoelectric properties (TE) of bulk nanocrystalline samples were investigated as a function of temperature 300 – 1000 K, respectively.