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Title: Impact of incomplete metal coverage on the electrical properties of metal-CNT contacts: A large-scale ab initio study

Abstract

Using a dedicated combination of the non-equilibrium Green function formalism and large-scale density functional theory calculations, we investigated how incomplete metal coverage influences two of the most important electrical properties of carbon nanotube (CNT)-based transistors: contact resistance and its scaling with contact length, and maximum current. These quantities have been derived from parameter-free simulations of atomic systems that are as close as possible to experimental geometries. Physical mechanisms that govern these dependences have been identified for various metals, representing different CNT-metal interaction strengths from chemisorption to physisorption. Our results pave the way for an application-oriented design of CNT-metal contacts.

Authors:
;  [1];  [2];  [3];  [2];  [2]; ; ;  [4];  [2];  [1];  [2];  [2]
  1. Institute for Materials Science and Max Bergman Center of Biomaterials, TU Dresden, 01062 Dresden (Germany)
  2. (Germany)
  3. Theoretical Chemistry, TU Dresden, 01062 Dresden (Germany)
  4. Chair for Electron Devices and Integrated Circuits, TU Dresden, 01062 Dresden (Germany)
Publication Date:
OSTI Identifier:
22594297
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 10; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARBON NANOTUBES; CHEMISORPTION; DENSITY FUNCTIONAL METHOD; ELECTRICAL PROPERTIES; GEOMETRY; GREEN FUNCTION; LENGTH; METALS; SCALING; SIMULATION; TRANSISTORS

Citation Formats

Fediai, Artem, E-mail: artem.fediai@nano.tu-dresden.de, Ryndyk, Dmitry A., Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Seifert, Gotthard, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden, Mothes, Sven, Schroter, Michael, Claus, Martin, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Cuniberti, Gianaurelio, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, and Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden. Impact of incomplete metal coverage on the electrical properties of metal-CNT contacts: A large-scale ab initio study. United States: N. p., 2016. Web. doi:10.1063/1.4962439.
Fediai, Artem, E-mail: artem.fediai@nano.tu-dresden.de, Ryndyk, Dmitry A., Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Seifert, Gotthard, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden, Mothes, Sven, Schroter, Michael, Claus, Martin, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Cuniberti, Gianaurelio, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, & Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden. Impact of incomplete metal coverage on the electrical properties of metal-CNT contacts: A large-scale ab initio study. United States. doi:10.1063/1.4962439.
Fediai, Artem, E-mail: artem.fediai@nano.tu-dresden.de, Ryndyk, Dmitry A., Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Seifert, Gotthard, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden, Mothes, Sven, Schroter, Michael, Claus, Martin, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Cuniberti, Gianaurelio, Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, and Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden. 2016. "Impact of incomplete metal coverage on the electrical properties of metal-CNT contacts: A large-scale ab initio study". United States. doi:10.1063/1.4962439.
@article{osti_22594297,
title = {Impact of incomplete metal coverage on the electrical properties of metal-CNT contacts: A large-scale ab initio study},
author = {Fediai, Artem, E-mail: artem.fediai@nano.tu-dresden.de and Ryndyk, Dmitry A. and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden and Seifert, Gotthard and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden and Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden and Mothes, Sven and Schroter, Michael and Claus, Martin and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden and Cuniberti, Gianaurelio and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden and Dresden Center for Computational Materials Science, TU Dresden, 01062 Dresden},
abstractNote = {Using a dedicated combination of the non-equilibrium Green function formalism and large-scale density functional theory calculations, we investigated how incomplete metal coverage influences two of the most important electrical properties of carbon nanotube (CNT)-based transistors: contact resistance and its scaling with contact length, and maximum current. These quantities have been derived from parameter-free simulations of atomic systems that are as close as possible to experimental geometries. Physical mechanisms that govern these dependences have been identified for various metals, representing different CNT-metal interaction strengths from chemisorption to physisorption. Our results pave the way for an application-oriented design of CNT-metal contacts.},
doi = {10.1063/1.4962439},
journal = {Applied Physics Letters},
number = 10,
volume = 109,
place = {United States},
year = 2016,
month = 9
}
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