Nucleation and growth of aluminium films on carbon layers

Abstract

New experimental data are presented about the nucleation and growth of aluminium on carbon layers, both evaporated onto rocksalt at temperatures between 170 and 315°C in ultra high vacuum at pressures below 10 −10 mbar. From micrographs taken from the stripped layers, nucleation rates and saturation densities of the Al particles are determined. By comparison of the data with a theoretical model for the kinetics of nucleation and growth of thin films, information is obtained about the critical nucleus, the adsorption energy, and the activation energy for surface diffusion. The results show that the kinetics are distinctly different for at least two distinguishable sets of deposition conditions, depending on the temperature of the carbon layers.