Thermal conductivity measurement of Ge-SixGe1-x core-shell nanowires using suspended microdevices

被引：0

作者：

Park, Hyun Joon ^{[1
]}

Nah, Jung Hyo ^{[2
]}

Tutuc, Emanuel ^{[3
]}

Seol, Jae Hun ^{[1
]}

机构：

[1] Univ. of Texas, Austin

来源：

Transactions of the Korean Society of Mechanical Engineers, B | 2015年 / 39卷 / 10期

关键词：

Core-shell structure; Germanium; Nanowire; Silicon; Thermal conductivity; Wheatstone bridge;

D O I：

10.3795/KSME-B.2015.39.10.825

中图分类号：

学科分类号：

摘要：

Theoretical calculations suggest that the thermoelectric figure of merit (ZT) can be improved by introducing a core-shell heterostructure to a semiconductor nanowire because of the reduced thermal conductivity of the nanowire. To experimentally verify the decrease in thermal conductivity in core-shell nanowires, the thermal conductivity of Ge-SixGe1-x core-shell nanowires grown by chemical vapor deposition (CVD) was measured using suspended microdevices. The silicon composition (Xsi) in the shells was measured to be about 0.65, and the remainder of the germanium in the shells was shown to play a role in decreasing defects originating from the lattice mismatch between the cores and shells. In addition to the standard four-point current- voltage (I-V) measurement, the measurement configuration based on the Wheatstone bridge was attempted to enhance the measurement sensitivity. The measured thermal conductivity values are in the range of 9- 13 W/mK at room temperature and are lower by approximately 30 than that of a germanium nanowire with a comparable diameter. © 2015 The Korean Society of Mechanical Engineers.

引用

页码：825 / 829

页数：4

共 19 条

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