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Title: Ion-assisted functional monolayer coating of nanorod arrays in hydrogen plasmas

Abstract

Uniformity of postprocessing of large-area, dense nanostructure arrays is currently one of the greatest challenges in nanoscience and nanofabrication. One of the major issues is to achieve a high level of control in specie fluxes to specific surface areas of the nanostructures. As suggested by the numerical experiments in this work, this goal can be achieved by manipulating microscopic ion fluxes by varying the plasma sheath and nanorod array parameters. The dynamics of ion-assisted deposition of functional monolayer coatings onto two-dimensional carbon nanorod arrays in a hydrogen plasma is simulated by using a multiscale hybrid numerical simulation. The numerical results show evidence of a strong correlation between the aspect ratios and nanopattern positioning of the nanorods, plasma sheath width, and densities and distributions of microscopic ion fluxes. When the spacing between the nanorods and/or their aspect ratios are larger, and/or the plasma sheath is wider, the density of microscopic ion current flowing to each of the individual nanorods increases, thus reducing the time required to apply a functional monolayer coating down to 11 s for a 7-{mu}m-wide sheath, and to 5 s for a 50-{mu}m-wide sheath. The computed monolayer coating development time is consistent with previous experimental reports on plasma-assistedmore » functionalization of related carbon nanostructures [B. N. Khare et al., Appl. Phys. Lett. 81, 5237 (2002)]. The results are generic in that they can be applied to a broader range of plasma-based processes and nanostructures, and contribute to the development of deterministic strategies of postprocessing and functionalization of various nanoarrays for nanoelectronic, biomedical, and other emerging applications.« less

Authors:
; ; ; ;  [1];  [2];  [3]
  1. Plasma Nanoscience at Complex Systems, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)
  2. (United States)
  3. (Singapore)
Publication Date:
OSTI Identifier:
20974850
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 2; Other Information: DOI: 10.1063/1.2480494; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ASPECT RATIO; COATINGS; CONTROL; CORRELATIONS; DENSITY; DEPOSITION; FABRICATION; HYDROGEN; IONS; NANOSTRUCTURES; PLASMA; PLASMA DENSITY; PLASMA SHEATH; PLASMA SIMULATION; SPECIFIC SURFACE AREA; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Tam, E., Levchenko, I., Ostrikov, K., Keidar, M., Xu, S., Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109-2140, and Plasma Sources and Applications Center, NIE, Nanyang Technological University, 637616 Singapore. Ion-assisted functional monolayer coating of nanorod arrays in hydrogen plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2480494.
Tam, E., Levchenko, I., Ostrikov, K., Keidar, M., Xu, S., Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109-2140, & Plasma Sources and Applications Center, NIE, Nanyang Technological University, 637616 Singapore. Ion-assisted functional monolayer coating of nanorod arrays in hydrogen plasmas. United States. doi:10.1063/1.2480494.
Tam, E., Levchenko, I., Ostrikov, K., Keidar, M., Xu, S., Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109-2140, and Plasma Sources and Applications Center, NIE, Nanyang Technological University, 637616 Singapore. Thu . "Ion-assisted functional monolayer coating of nanorod arrays in hydrogen plasmas". United States. doi:10.1063/1.2480494.
@article{osti_20974850,
title = {Ion-assisted functional monolayer coating of nanorod arrays in hydrogen plasmas},
author = {Tam, E. and Levchenko, I. and Ostrikov, K. and Keidar, M. and Xu, S. and Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109-2140 and Plasma Sources and Applications Center, NIE, Nanyang Technological University, 637616 Singapore},
abstractNote = {Uniformity of postprocessing of large-area, dense nanostructure arrays is currently one of the greatest challenges in nanoscience and nanofabrication. One of the major issues is to achieve a high level of control in specie fluxes to specific surface areas of the nanostructures. As suggested by the numerical experiments in this work, this goal can be achieved by manipulating microscopic ion fluxes by varying the plasma sheath and nanorod array parameters. The dynamics of ion-assisted deposition of functional monolayer coatings onto two-dimensional carbon nanorod arrays in a hydrogen plasma is simulated by using a multiscale hybrid numerical simulation. The numerical results show evidence of a strong correlation between the aspect ratios and nanopattern positioning of the nanorods, plasma sheath width, and densities and distributions of microscopic ion fluxes. When the spacing between the nanorods and/or their aspect ratios are larger, and/or the plasma sheath is wider, the density of microscopic ion current flowing to each of the individual nanorods increases, thus reducing the time required to apply a functional monolayer coating down to 11 s for a 7-{mu}m-wide sheath, and to 5 s for a 50-{mu}m-wide sheath. The computed monolayer coating development time is consistent with previous experimental reports on plasma-assisted functionalization of related carbon nanostructures [B. N. Khare et al., Appl. Phys. Lett. 81, 5237 (2002)]. The results are generic in that they can be applied to a broader range of plasma-based processes and nanostructures, and contribute to the development of deterministic strategies of postprocessing and functionalization of various nanoarrays for nanoelectronic, biomedical, and other emerging applications.},
doi = {10.1063/1.2480494},
journal = {Physics of Plasmas},
number = 2,
volume = 14,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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