| Numéro |
J. Phys. Colloques
Volume 48, Numéro C6, Novembre 1987
34th International Field Emission Symposium / 34ème Symposium International d'Emission de Champ
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| Page(s) | C6-257 - C6-262 | |
| DOI | https://doi.org/10.1051/jphyscol:1987642 | |
J. Phys. Colloques 48 (1987) C6-257-C6-262
DOI: 10.1051/jphyscol:1987642
STUDIES OF NEGATIVE FIELD ION MICROSCOPY WITH TETRACYANOETHYLENE
R. Schmitz1, F. Okuyama2 et F.W. Röllgen11 Institute of Physical Chemistry, University of Bonn, Wegelerstr.12, D-5300 Bonn 1, F.R.G.
2 Nagoya Institute of Technology, Nagoya 466, Japan
Abstract
Negative ion images generated by tetracyanoethylene (TCNE) under inverted field conditions in a field ion microscope have been investigated in more detail. The experiments confirm previous findings / l / and reveal further unique ionization phenomena such as the discontinuous development of ring structures in the ion image, the oscillation of rings in size and switching between different ion emitting surface structures. The observation of these phenomena critically depends on maintaining a tip temperature lower than the ambient gas temperature. The phenomena are attributed to the formation of an electrically conducting polymer layer of TCNE and to an elastic response of the layer surface to the field stress. Thus field enhancing and ion emitting protrusions are formed.