Chapter 1: Structural Characterization

Abstract

This chapter presents some important requirements for the structural and chemical characterization of thin metal films. The need for both microscopic and spectroscopic methods has been discussed. For an appreciation of the structural properties of thin metal films, some knowledge of the basic nucleation and growth mechanisms is necessary because most macroscopic physical and chemical properties of thin films depend strongly on the initial condensation behavior during production. The island growth mode is discussed in the chapter because it has been investigated most systematically both by experiments and by theoretical models. It is easy to analyze the structure of a film after it has been produced. However, it is more difficult to produce a film with predetermined properties that may be desired for a special purpose; many parameters govern the development of structure in thin films—such as defects, coalescence, recrystallization, or environment—and a detailed knowledge of the respective influences would be required. It is ambiguous to predict the behavior of a special overgrowth-substrate system from only the experience from model systems, such as noble metals on alkali halides. Each system exhibits more or less pronounced peculiarities, depending on the production parameters. This has to be taken into account when, for example, correlations between the morphology and chemical activity of thin films are investigated.