Applied Physics A

, Volume 73, Issue 4, pp 409–418

Raman spectroscopy and field-emission properties of CVD-grown carbon-nanotube films

  • M. Sveningsson
  • R.-E. Morjan
  • O.A. Nerushev
  • Y. Sato
  • J. Bäckström
  • E.E.B. Campbell
  • F. Rohmund
Article

DOI: 10.1007/s003390100923

Cite this article as:
Sveningsson, M., Morjan, R., Nerushev, O. et al. Appl Phys A (2001) 73: 409. doi:10.1007/s003390100923

Abstract.

Carbon-nanotube films are very efficient cathodes for field-emission devices. This study presents a comprehensive comparison between structural, spectroscopic and field-emission properties of films of aligned and non-aligned multi-wall nanotubes (MWNTs) which are grown by thermal chemical vapour deposition. Three types of films are investigated: vertically aligned MWNTs with clean and coated nanotube side walls as well as non-aligned MWNT films. Raman spectra taken on the aligned MWNT films consist of many lines of first-, second- and third-order signals. Several lines are reported here for the first time for MWNTs. The presence of the surface coating leads to a decrease and broadening of the higher-order signals as well as an increase in the disorder-induced contributions in the first-order regime. The aligned MWNT films have excellent field-emission properties with very high emission current densities and low turn-on and threshold fields. The presence of a surface coating has no impact on the efficiency of the field-emission process. Films of non-aligned MWNTs show considerably reduced electron-emission current densities and larger critical fields.

PACS: 81.07.De; 85.45.Db; 78.30.Na

Copyright information

© Springer-Verlag 2001

Authors and Affiliations

  • M. Sveningsson
    • 1
  • R.-E. Morjan
    • 1
  • O.A. Nerushev
    • 1
  • Y. Sato
    • 1
  • J. Bäckström
    • 1
  • E.E.B. Campbell
    • 1
  • F. Rohmund
    • 1
  1. 1.Department of Experimental Physics, Gothenburg University and Chalmers University of Technology, 41296 Gothenburg, SwedenSE