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Title: Impact of the etching gas on vertically oriented single wall and few walled carbon nanotubes by plasma enhanced chemical vapor deposition

Abstract

Vertically oriented single wall nanotubes (SWNTs) and few walled nanotubes (FWNTs) have been grown by electronic cyclotron resonance plasma enhanced chemical vapor deposition (PECVD) on silica flat substrates. The impact of the plasma parameters on SWNT and FWNT growth has been investigated using two different etching gas mixtures, namely, C{sub 2}H{sub 2}/NH{sub 3} and C{sub 2}H{sub 2}/H{sub 2} with various ratios and applied bias voltages. Kinetic studies are also proposed in order to describe the FWNT growth mechanism by plasma techniques. A key role played by the reactive gas (NH{sub 3} and H{sub 2}) is observed in the PECVD process, contrary to multiwalled nanotube growth. It is demonstrated that the balance between FWNT growth versus FWNT etching can be widely modulated by varying the gas mixture and bias voltage. It is shown that the use of hydrogen for hydrocarbon gas dilution restricts the destruction of SWNT and FWNT by the plasma species (ions and radicals)

Authors:
; ; ;  [1];  [2];  [2]
  1. IMN-PCM, UMR 6502 CNRS-Universite de Nantes, BP 32229, 44322 Nantes (France)
  2. (France)
Publication Date:
OSTI Identifier:
20982735
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 5; Other Information: DOI: 10.1063/1.2654647; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMMONIA; CARBON; CHEMICAL VAPOR DEPOSITION; CRYSTAL GROWTH; CYCLOTRON RESONANCE; ELECTRIC POTENTIAL; ETCHING; HYDROCARBONS; HYDROGEN; IONS; MIXTURES; NANOTUBES; PLASMA; RADICALS; SUBSTRATES

Citation Formats

Gohier, A., Minea, T. M., Djouadi, M. A., Granier, A., LPGP, UMR 8578 CNRS-Universite Paris Sud, Batiment 210, 91405 Orsay, and IMN-PCM, UMR 6502 CNRS-Universite de Nantes, BP 32229, 44322 Nantes. Impact of the etching gas on vertically oriented single wall and few walled carbon nanotubes by plasma enhanced chemical vapor deposition. United States: N. p., 2007. Web. doi:10.1063/1.2654647.
Gohier, A., Minea, T. M., Djouadi, M. A., Granier, A., LPGP, UMR 8578 CNRS-Universite Paris Sud, Batiment 210, 91405 Orsay, & IMN-PCM, UMR 6502 CNRS-Universite de Nantes, BP 32229, 44322 Nantes. Impact of the etching gas on vertically oriented single wall and few walled carbon nanotubes by plasma enhanced chemical vapor deposition. United States. doi:10.1063/1.2654647.
Gohier, A., Minea, T. M., Djouadi, M. A., Granier, A., LPGP, UMR 8578 CNRS-Universite Paris Sud, Batiment 210, 91405 Orsay, and IMN-PCM, UMR 6502 CNRS-Universite de Nantes, BP 32229, 44322 Nantes. Thu . "Impact of the etching gas on vertically oriented single wall and few walled carbon nanotubes by plasma enhanced chemical vapor deposition". United States. doi:10.1063/1.2654647.
@article{osti_20982735,
title = {Impact of the etching gas on vertically oriented single wall and few walled carbon nanotubes by plasma enhanced chemical vapor deposition},
author = {Gohier, A. and Minea, T. M. and Djouadi, M. A. and Granier, A. and LPGP, UMR 8578 CNRS-Universite Paris Sud, Batiment 210, 91405 Orsay and IMN-PCM, UMR 6502 CNRS-Universite de Nantes, BP 32229, 44322 Nantes},
abstractNote = {Vertically oriented single wall nanotubes (SWNTs) and few walled nanotubes (FWNTs) have been grown by electronic cyclotron resonance plasma enhanced chemical vapor deposition (PECVD) on silica flat substrates. The impact of the plasma parameters on SWNT and FWNT growth has been investigated using two different etching gas mixtures, namely, C{sub 2}H{sub 2}/NH{sub 3} and C{sub 2}H{sub 2}/H{sub 2} with various ratios and applied bias voltages. Kinetic studies are also proposed in order to describe the FWNT growth mechanism by plasma techniques. A key role played by the reactive gas (NH{sub 3} and H{sub 2}) is observed in the PECVD process, contrary to multiwalled nanotube growth. It is demonstrated that the balance between FWNT growth versus FWNT etching can be widely modulated by varying the gas mixture and bias voltage. It is shown that the use of hydrogen for hydrocarbon gas dilution restricts the destruction of SWNT and FWNT by the plasma species (ions and radicals)},
doi = {10.1063/1.2654647},
journal = {Journal of Applied Physics},
number = 5,
volume = 101,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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