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Title: Spin-on-doping for output power improvement of silicon nanowire array based thermoelectric power generators

Abstract

The output power of a silicon nanowire array (NWA)-bulk thermoelectric power generator (TEG) with Cu contacts is improved by spin-on-doping (SOD). The Si NWAs used in this work are fabricated via metal assisted chemical etching (MACE) of 0.01–0.02 Ω cm resistivity n- and p-type bulk, converting ~4% of the bulk thickness into NWs. The MACE process is adapted to ensure crystalline NWs. Current-voltage and Seebeck voltage-temperature measurements show that while SOD mainly influences the contact resistance in bulk, it influences both contact resistance and power factor in NWA-bulk based TEGs. According to our experiments, using Si NWAs in combination with SOD increases the output power by an order of 3 under the same heating power due to an increased power factor, decreased thermal conductivity of the NWA and reduced Si-Cu contact resistance.

Authors:
;  [1]
  1. Department of Electrical and Electronic Engineering, Imperial College London, Exhibition Road, SW7 2BT London (United Kingdom)
Publication Date:
OSTI Identifier:
22304222
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 21; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; COPPER; CURRENTS; ELECTRIC CONTACTS; ELECTRIC POTENTIAL; ETCHING; METALS; NANOWIRES; POWER FACTOR; SILICON; SPIN; SUPEROXIDE DISMUTASE; TEMPERATURE MEASUREMENT; THERMAL CONDUCTIVITY; THERMOELECTRIC GENERATORS; THICKNESS; NESDPS Office of Nuclear Energy Space and Defense Power Systems

Citation Formats

Xu, B., E-mail: bin.xu09@imperial.ac.uk, and Fobelets, K. Spin-on-doping for output power improvement of silicon nanowire array based thermoelectric power generators. United States: N. p., 2014. Web. doi:10.1063/1.4881781.
Xu, B., E-mail: bin.xu09@imperial.ac.uk, & Fobelets, K. Spin-on-doping for output power improvement of silicon nanowire array based thermoelectric power generators. United States. doi:10.1063/1.4881781.
Xu, B., E-mail: bin.xu09@imperial.ac.uk, and Fobelets, K. Sat . "Spin-on-doping for output power improvement of silicon nanowire array based thermoelectric power generators". United States. doi:10.1063/1.4881781.
@article{osti_22304222,
title = {Spin-on-doping for output power improvement of silicon nanowire array based thermoelectric power generators},
author = {Xu, B., E-mail: bin.xu09@imperial.ac.uk and Fobelets, K.},
abstractNote = {The output power of a silicon nanowire array (NWA)-bulk thermoelectric power generator (TEG) with Cu contacts is improved by spin-on-doping (SOD). The Si NWAs used in this work are fabricated via metal assisted chemical etching (MACE) of 0.01–0.02 Ω cm resistivity n- and p-type bulk, converting ~4% of the bulk thickness into NWs. The MACE process is adapted to ensure crystalline NWs. Current-voltage and Seebeck voltage-temperature measurements show that while SOD mainly influences the contact resistance in bulk, it influences both contact resistance and power factor in NWA-bulk based TEGs. According to our experiments, using Si NWAs in combination with SOD increases the output power by an order of 3 under the same heating power due to an increased power factor, decreased thermal conductivity of the NWA and reduced Si-Cu contact resistance.},
doi = {10.1063/1.4881781},
journal = {Journal of Applied Physics},
number = 21,
volume = 115,
place = {United States},
year = {Sat Jun 07 00:00:00 EDT 2014},
month = {Sat Jun 07 00:00:00 EDT 2014}
}
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