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Title: Resistivity scaling and electron relaxation times in metallic nanowires

Abstract

We study the resistivity scaling in nanometer-sized metallic wires due to surface roughness and grain-boundaries, currently the main cause of electron scattering in nanoscaled interconnects. The resistivity has been obtained with the Boltzmann transport equation, adopting the relaxation time approximation of the distribution function and the effective mass approximation for the conducting electrons. The relaxation times are calculated exactly, using Fermi's golden rule, resulting in a correct relaxation time for every sub-band state contributing to the transport. In general, the relaxation time strongly depends on the sub-band state, something that remained unclear with the methods of previous work. The resistivity scaling is obtained for different roughness and grain-boundary properties, showing large differences in scaling behavior and relaxation times. Our model clearly indicates that the resistivity is dominated by grain-boundary scattering, easily surpassing the surface roughness contribution by a factor of 10.

Authors:
 [1];  [2]; ;  [3];  [2];  [3]
  1. Instituut voor Theoretische Fysica, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium)
  2. (Belgium)
  3. Imec, Kapeldreef 75, B-3001 Leuven (Belgium)
Publication Date:
OSTI Identifier:
22314610
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOLTZMANN EQUATION; DISTRIBUTION FUNCTIONS; EFFECTIVE MASS; GRAIN BOUNDARIES; QUANTUM WIRES; RELAXATION TIME; ROUGHNESS; SCATTERING; SURFACES

Citation Formats

Moors, Kristof, E-mail: kristof@itf.fys.kuleuven.be, Imec, Kapeldreef 75, B-3001 Leuven, Sorée, Bart, Magnus, Wim, Physics Department, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, and Tőkei, Zsolt. Resistivity scaling and electron relaxation times in metallic nanowires. United States: N. p., 2014. Web. doi:10.1063/1.4892984.
Moors, Kristof, E-mail: kristof@itf.fys.kuleuven.be, Imec, Kapeldreef 75, B-3001 Leuven, Sorée, Bart, Magnus, Wim, Physics Department, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, & Tőkei, Zsolt. Resistivity scaling and electron relaxation times in metallic nanowires. United States. doi:10.1063/1.4892984.
Moors, Kristof, E-mail: kristof@itf.fys.kuleuven.be, Imec, Kapeldreef 75, B-3001 Leuven, Sorée, Bart, Magnus, Wim, Physics Department, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, and Tőkei, Zsolt. 2014. "Resistivity scaling and electron relaxation times in metallic nanowires". United States. doi:10.1063/1.4892984.
@article{osti_22314610,
title = {Resistivity scaling and electron relaxation times in metallic nanowires},
author = {Moors, Kristof, E-mail: kristof@itf.fys.kuleuven.be and Imec, Kapeldreef 75, B-3001 Leuven and Sorée, Bart and Magnus, Wim and Physics Department, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen and Tőkei, Zsolt},
abstractNote = {We study the resistivity scaling in nanometer-sized metallic wires due to surface roughness and grain-boundaries, currently the main cause of electron scattering in nanoscaled interconnects. The resistivity has been obtained with the Boltzmann transport equation, adopting the relaxation time approximation of the distribution function and the effective mass approximation for the conducting electrons. The relaxation times are calculated exactly, using Fermi's golden rule, resulting in a correct relaxation time for every sub-band state contributing to the transport. In general, the relaxation time strongly depends on the sub-band state, something that remained unclear with the methods of previous work. The resistivity scaling is obtained for different roughness and grain-boundary properties, showing large differences in scaling behavior and relaxation times. Our model clearly indicates that the resistivity is dominated by grain-boundary scattering, easily surpassing the surface roughness contribution by a factor of 10.},
doi = {10.1063/1.4892984},
journal = {Journal of Applied Physics},
number = 6,
volume = 116,
place = {United States},
year = 2014,
month = 8
}
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