Step and island dynamics at solid/vacuum and solid/liquid interfaces

The investigation of step and island dynamics on surfaces has enormously contributed to the microscopic understanding of mass transport processes in equilibrium, during growth and coarsening of surface structures. From the scaling behavior of step fluctuations as well as of the ripening of mono- and multilayer islands, the atomic diffusion processes may be unambiguously determined even when single atom motion cannot be observed directly. This is the case for metal surfaces at high temperatures and, in particular, for metal electrodes in electrochemical environment. In the case of the latter, the analysis of step and island dynamics is the only method available to date to learn about the dynamics at the solid/liquid interface on the atomic scale. Here, we review the basic theoretical principles and the experimental contributions on step and island dynamics performed in ultra-high vacuum as well as (more recently) in electrolyte. It focuses also on the comparison between experimental results obtained at the solid/vacuum and at the solid/liquid interface. (C) 2001 Elsevier Science Ltd. All rights reserved.