Large reduction in thermal conductivity for SiGe alloy nanowire wrapped with a Ge nanoparticle-embedded SiO2 shell.
We demonstrate silicon germanium (SiGe) alloy nanowires (NWs) with Ge nanoparticles (GeNPs) embedded in a SiO2 shell as a material for decreasing thermal conductivity. During thermal oxidation of SiGe NWs to form SiGe-SiO2 core-shell structures, Ge atoms were diffused into the SiO2 shell to relax the strain in the SiGe core, and agglomerated as a few nanometer-sized particles. This structure leads to a large reduction in thermal conductivity due to the GeNP-phonon interaction, while electrical conductivity is sustained because the core of the SiGe alloy NW provides a current path for the charged carriers. The thermal conductivity of the SiGe alloy NWs wrapped with a GeNP-embedded SiO2 shell is 0.41 W m(-1) K(-1) at 300 K.
SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon, 440-746, Korea. Research Center for Time-Domain Nano-Functional Devices, Samsung Advanced Institute of Technology, Youngtong-gu, Suwon-si, 443-803, Korea.
Jong Woon
JW
Lee
Junho
J
Lee
Su-Ho
SH
Jung
Yamujin
Y
Jang
Byoung Lyong
BL
Choi
Cheol-Woong
CW
Yang
Dongmok
D
Whang
Eun Kyung
EK
Lee