| Numéro |
J. Phys. Colloques
Volume 47, Numéro C2, Mars 1986
32 nd International Field Emission Symposium / 32ème Symposium International d'Emission de Champ
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| Page(s) | C2-47 - C2-51 | |
| DOI | https://doi.org/10.1051/jphyscol:1986207 | |
J. Phys. Colloques 47 (1986) C2-47-C2-51
DOI: 10.1051/jphyscol:1986207
FIELD ION- AND ELECTRON-EMISSION MEASUREMENTS ON SINGLE METAL CLUSTERS : Re ON W(110)
N. ERNST1 et G. EHRLICH21 Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-1000 Berlin 33, F.R.G.
2 Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, U.S.A.
Abstract
Using a combined probe hole FIM-FEM, Fowler-Nordheim studies have been carried out on tungsten emitters prepared by sputtering and field evaporation. The projection of the iris probe hole onto a W(110) plane could be made as small as the unit cell of W(110), mapped out by adatom diffusion. A dependence of (110) work function values on plane size as well as on tip radius has been observed, arising from variations in the local field strength and from contributions to the probe hole current from surrounding low work function areas. A distinct difference in electron emission behaviour between Re5/W(110) and Re1/W(110) was detected. Re1 slightly enhances the local field emission current ; Re5 causes a current decrease. Changes of FN preexponential factors and of local work functions caused by adsorption of a single Re atom and a Re cluster will be presented.