Microsc. Microanal. Microstruct. 6, 113-120 (1995)
DOI: 10.1051/mmm:1995111

Dispersion of the Valence Electron Energy Loss in Thin Amorphous Carbon Films deposited by Ion Assisted Evaporation of Graphite

Uwe Falke, Anne-Katrin Weber et Jens Ullmann

TU Chemnitz-Zwickau, Institut für Physik, D-09107 Chemnitz, Germany

Abstract
The dispersion of electron energy loss with transferred wave vector q has been measured for amorphous, non-hydrogenated carbon films. The peak energies for both the loss peak related to the main plasmon loss and for that brought about by the interband transitions are found to follow a power law in q. The films exhibited differences of the exponents which may be related to structural differences. For the material deposited with very small ion flux, which is quite similar to ordinary evaporated carbon, a dispersion of the two low loss peaks with q^1.6 and q^1.9, respectively, has been found whereas in the case of the other two films, the dispersion appears to be nearly linear in q.

PACS
7920K - Other electron surface impact phenomena.
7360F - Electronic properties of semiconductor thin films.
7145G - Exchange, correlation, dielectric and magnetic functions, plasmons.
6180M - Channelling, blocking and energy loss of particles.

Key words
amorphous semiconductors -- carbon -- electron energy loss spectra -- elemental semiconductors -- plasmons -- semiconductor thin films -- vapour deposited coatings -- valence electron energy loss dispersion -- thin amorphous films -- ion assisted evaporation -- graphite -- transferred wave vector -- nonhydrogenated films -- plasmon loss -- interband transitions -- power law -- low loss peaks -- EELS -- C


© EDP Sciences 1995