Characterization of atomic-structure, adsorption and thin film growth on solid surfaces by ion scattering and recoiling spectroscopy (SARS).

E.A. SÁNCHEZ, J.E. GAYONE, O. GRIZZI

Mérida, Venezuela

Simposio; The Third San Luis Symposium on Surfaces, Interfaces and Catalysis; 2004

Ion probes provide information about certain problems in surface science which is complementary to that given by electron sources, and sometimes is unique, as in the case of hydrogen adsorption on surfaces, and detection of elements in small quantities (fractions of a monolayer). As in the case of electron probes, ions produce the emission of ionized an neutral atoms, electrons and photons. Each combination of ions going in and particles going out gives rise to one or more well established surface analysis techniques. In this talk we will concentrate on the information that can be obtained from the combination of ions at keV energies going in and the resulting ions or neutrals going out. This technique is known as Ion Scattering and Recoiling Spectroscopy and gives information on the composition (type and quantity of elements) of solid surfaces, structure (location and defects) of single crystalline surfaces, and some information about the surface electronic states.  We will describe the experimental requirements, the basic concepts involved in this technique, and will present examples of applications to the study of  adsorption of atoms (H, K, Cs) and molecules (AlF3, SH-CnH2n+1) on clean GaAs(110) and Ag(111) surfaces.