Surface Characterization by Medium Energy Particle Scattering

Abstract

At the atomic scale, it is quite difficult to devise truly non-destructive measurement procedures because to do so requires a probe which gives specific quantitative, chemical or structural information without breaking chemical bonds. Ion beam analytical techniques using MeV beams are well known and versatile tools for characterizing surfaces and are generally considered to be nondestructive to most inorganic materials, although the electrical properties of the sample are usually altered. In this article, we discuss recently developed scattering techniques using time-of-flight particle detection that work well with ions whose energies are at least an order of magnitude lower than those required for conventional analyses. This reduction in the ion beam energy makes possible novel measurements such as the characterization of thin films on polymer substrates as well as enhanced capabilities such as improved depth resolution and increased sensitivity for trace element detection.