| Issue |
J. Phys. Colloques
Volume 49, Number C6, Novembre 1988
35th International Field Emission Symposium / 35éme Symposium International d'Emission de Champ
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| Page(s) | C6-203 - C6-208 | |
| DOI | https://doi.org/10.1051/jphyscol:1988634 | |
J. Phys. Colloques 49 (1988) C6-203-C6-208
DOI: 10.1051/jphyscol:1988634
FIELD INDUCED ADSORPTION AT AN AMORPHOUS SILICON SURFACE STUDIED BY FIELD ION MICROSCOPY
H.B. ELSWIJK, G.P.E.M. van BAKEL et J.Th.M. DE HOSSONDepartment of Applied Physics, Materials Science Centre, University of Groningen, Nijenborgh 18, NL-9747 AG Groningen, The Netherlands
Abstract
Flickering and hopping of spots in the argon image of an a-Si:H layer on tungsten was investigated by studying the kinetics of the responsible adsorption and desorption processes as a function of tip temperature and imaging gas pressure. The localized binding energy of argon adsorbates on silicon is calculated using the isolated dipole model which yields a value of 0.20 eV. An increase of the gas pressure decreases the average residence times in both states which constitute a flickering or hopping phenomenon. Decreasing the tip temperature leads to opposite responses of the two residence times. These results do not support a model in which desorption is thermally activated. Both the adsorption and desorption rate are predominantly governed by the imaging gas pressure. A desorption process activated by image gas impact is suggested.