The kinetics of island nucleation, coalescence and growth during deposition
of Au atoms on amorphous carbon are studied experimentally and the obtaine
d results are analysed using rate equations. Rutherford backscattering spec
troscopy (RBS), transmission electron microscopy (TEM), grazing-incidence s
mall angle scattering (GISAXS) and atomic force microscopy (AFM) techniques
are used to measure the quantity of deposited Au, density, size and averag
e height of the islands as a function of time. Parameters used in rate equa
tions are deduced from a quantitative comparison between calculated and exp
erimental evolution of the above dependencies. Suggested rate equations tak
e into account the adsorption rate on a bare substrate as well as on existi
ng islands, the mobility of adatoms, possible redistribution of atoms betwe
en islands and bare substrate and coalescence of islands. The rate equation
s are used to study the kinetics of the coverage of a carbon substrate by g
old atoms and the kinetics of the island density. It is shown that experime
ntal and calculated dependencies are in agreement if the mobility of island
s is included. (C) 2000 Elsevier Science S.A. All rights reserved.