Design, construction and use of a fast atom scattering spectrometer

Abstract

Atom-surface scattering can provide information on surface composition, surface structure and surface dynamics without many of the problems associated with charged particle beams. The technique of ion-scattering spectrometry (ISS) is now well established and this paper describes a development of this technique involving the use of an uncharged fast atom beam (FAB) source in place of an ion source. The particular problem associated with the use of neutral particles in this application is in the accurate measurement of particle energy where conventional electrostatic methods cannot be employed. This was overcome by developing a time-of-flight (TOF) system consisting of a nanosecond pulsing system for the source together with detection and data acquisition and processing systems. The design, development and construction of the system is described in detail. The use of the TOF system to characterize the source fully is described, and the results of some initial atom-surface scattering experiments are given.