Ion sputtering, surface topography, SPM and surface analysis of electronic materials

Two side effects introduced on surfaces of electronic materials by ion bombardment, namely compositional changes for compound semiconductors. and topography changes are discussed. Based on the relative elemental sensitivity factor method with matrix corrections for quantitative AES or XPS analysis, a sputter correction factor is defined to compensate for bombardment induced surface compositional changes. Using several popular preferential sputter models and comparing their predictions to a synopsis of published experimental AES and XPS measurements on argon bombarded binary compound semiconductors, a sputter correction factor for these materials are proposed. The extent of bombardment-induced topography depends primarily on the substrate material while the ion beam characteristics play only a secondary role. Due to the complexity of and the many processes involved in ionrsolid interactions, bombardment-induced topography is not well understood. Several quantitative and qualitative theories have been proposed to explain the experimental data. Most of these theories are based on SEM or TEM data. The major disadvantage of these data is the lack of quantitative information. The advent of SPM scanning probe microscopy.and the subsequent development of software have reversed this. A brief summary of SPM AFM and STM.investigations of bombardment induced topography on semiconductor surfaces is given. Most studies have concentrated on the topography on Si, Ge, GaAs and InP surfaces with special emphasis on ripple development. q1999 Elsevier Science B.V. All rights reserved.