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Title: Four-probe measurements of the in-plane thermoelectric properties of nanofilms

Abstract

Measuring in-plane thermoelectric properties of submicron thin films has remained a challenging task. Here we report a method based on a suspended microdevice for four-probe measurements of the Seebeck coefficient, thermal conductivity, electrical conductivity, and thermoelectric figure of merit of patterned indium arsenide (InAs) nanofilms assembled on the microdevice. The contact thermal resistance and intrinsic thermal resistance of the 40 nm thick InAs nanofilm sample were measured by using the nanofilm itself as a differential thermocouple to determine the temperature drops at the contacts. The microdevice was also used to measure a 190 nm thick silicon dioxide (SiO{sub 2}) film and the results were compared with those reported in the literature. A through-substrate hole under the suspended microdevice allows for transmission electron microscopy characterization of the nanofilm sample assembled on the device. This capability enables one to correlate the measured thermoelectric properties with the crystal structures of the nanofilm.

Authors:
; ; ;  [1]
  1. Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712 and Center for Nano and Molecular Science and Technology, Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712 (United States)
Publication Date:
OSTI Identifier:
20953397
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 3; Other Information: DOI: 10.1063/1.2712894; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL STRUCTURE; ELECTRIC CONDUCTIVITY; EQUIPMENT; INDIUM; INDIUM ARSENIDES; PROBES; SEEBECK EFFECT; SEMICONDUCTOR MATERIALS; SILICA; SILICON OXIDES; THERMAL CONDUCTIVITY; THERMOCOUPLES; THERMOELECTRIC PROPERTIES; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Mavrokefalos, Anastassios, Pettes, Michael T., Zhou Feng, and Shi Li. Four-probe measurements of the in-plane thermoelectric properties of nanofilms. United States: N. p., 2007. Web. doi:10.1063/1.2712894.
Mavrokefalos, Anastassios, Pettes, Michael T., Zhou Feng, & Shi Li. Four-probe measurements of the in-plane thermoelectric properties of nanofilms. United States. doi:10.1063/1.2712894.
Mavrokefalos, Anastassios, Pettes, Michael T., Zhou Feng, and Shi Li. Thu . "Four-probe measurements of the in-plane thermoelectric properties of nanofilms". United States. doi:10.1063/1.2712894.
@article{osti_20953397,
title = {Four-probe measurements of the in-plane thermoelectric properties of nanofilms},
author = {Mavrokefalos, Anastassios and Pettes, Michael T. and Zhou Feng and Shi Li},
abstractNote = {Measuring in-plane thermoelectric properties of submicron thin films has remained a challenging task. Here we report a method based on a suspended microdevice for four-probe measurements of the Seebeck coefficient, thermal conductivity, electrical conductivity, and thermoelectric figure of merit of patterned indium arsenide (InAs) nanofilms assembled on the microdevice. The contact thermal resistance and intrinsic thermal resistance of the 40 nm thick InAs nanofilm sample were measured by using the nanofilm itself as a differential thermocouple to determine the temperature drops at the contacts. The microdevice was also used to measure a 190 nm thick silicon dioxide (SiO{sub 2}) film and the results were compared with those reported in the literature. A through-substrate hole under the suspended microdevice allows for transmission electron microscopy characterization of the nanofilm sample assembled on the device. This capability enables one to correlate the measured thermoelectric properties with the crystal structures of the nanofilm.},
doi = {10.1063/1.2712894},
journal = {Review of Scientific Instruments},
number = 3,
volume = 78,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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