Electron spectroscopy imaging to study ELNES at a nanoscale

Series of energy‐filtered TEM images have been acquired with very narrow energy slit using a post‐column energy filter. This allowed us to reconstruct spectra with an energy resolution estimated to 2 eV, and a spatial resolution in the order of 0.5 nm. In that way, fine structures of the N‐K edge in AlN/GaN heterostructures have been investigated and compared to EELS spectra. The fine structure in the two nitrides is very sensitive to the local environment. Very good agreement between ESI and EELS spectra was found. Moreover, this technique allowed analysis of the AlN/GaN interface at a nanoscale. The second example is an application of the technique to construct bonding maps. In this case, maps differentiating AlN nanoprecipitates with either the cubic or the hexagonal phase were created.

[1]  T. Epicier,et al.  N‐K ELNES study of anisotropy effects in hexagonal AlN , 2003, Journal of microscopy.

[2]  M. Sennour,et al.  Contribution of advanced microscopy techniques to nano-precipitates characterization: case of AlN precipitation in low-carbon steel , 2003 .

[3]  Ray F. Egerton,et al.  Electron Energy-Loss Spectroscopy , 1997, Microscopy and Microanalysis.

[4]  A. Barbier,et al.  Development of a quantitative energy filtering TEM method to study a reactive NiO/80Ni20Fe interface. , 2001, Ultramicroscopy.

[5]  M. Mackenzie,et al.  Quantifying the oxidation of AlN using electron energy loss spectroscopy , 2000 .

[6]  Alan J. Craven,et al.  The near-edge structure in energy-loss spectroscopy: many-electron and magnetic effects in transition metal nitrides and carbides , 2000 .

[7]  J. Plitzko,et al.  Quantitative thin film analysis by energy filtering transmission electron microscopy , 1999 .

[8]  Guy Feuillet,et al.  Quantitative characterization of GaN quantum-dot structures in AlN by high-resolution transmission electron microscopy , 1999 .

[9]  T. Moustakas,et al.  Nitrogen K-edge NEXAFS measurements on group-III binary and ternary nitrides. , 1999, Journal of synchrotron radiation.

[10]  Gianluigi A. Botton,et al.  Imaging, spectroscopy and spectroscopic imaging with an energy filtered field emission TEM , 1999 .

[11]  C. Colliex,et al.  EELS investigation of the electron conduction-band states in wurtzite AlN and oxygen-doped AlN(O) , 1998 .

[12]  Theodore D. Moustakas,et al.  Density of states, hybridization, and band-gap evolution in AlxGa1-xN alloys , 1998 .

[13]  David J. Singh,et al.  Connections between the electron-energy-loss spectra, the local electronic structure, and the physical properties of a material: A study of nickel aluminum alloys , 1998 .

[14]  G. Kothleitner,et al.  Quantitative analysis of EFTEM elemental distribution images , 1997 .

[15]  R. Egerton,et al.  The effect of lens aberrations on the spatial resolution of an energy-filtered TEM image , 1997 .

[16]  K. Kimoto,et al.  Spatial resolution in EFTEM elemental maps , 1995 .

[17]  C Jeanguillaume,et al.  Electron energy loss spectrometry mapping , 1994 .

[18]  H. Kohl,et al.  Optimum imaging parameters for elemental mapping in an energy filtering transmission electron microscope , 1993 .

[19]  O. Krivanek,et al.  Developments in EELS instrumentation for spectroscopy and imaging , 1991 .

[20]  R. Brydson,et al.  EELS as a fingerprint of the chemical co-ordination of light elements , 1991 .

[21]  Christian Colliex,et al.  Spectrum-image: The next step in EELS digital acquisition and processing , 1989 .

[22]  P. Richter,et al.  The Effect of Lens Aberrations on a Coherent Optical Filter , 1975 .