Applications of Secondary and Backscattered Electron Spectroscopic Imaging and a Proposal for New SEM Image...

With the increasing diversity of SEM detectors today, classification based solely on secondary and backscattered electrons is no longer sufficient; there is a growing need to specify energy and emission direction when discussing image information. In particular, for detectors capable of energy discrimination, an appropriate method for classifying images is required. We propose a nomenclature for classifying images by explicitly indicating energy, emission direction, and detector position following the abbreviations "SE" and "BE." Energy is displayed as three bands - A, B, and C- defined by the ends of the spectrum on a logarithmic axis, while emission direction is divided into regions 1, 2, and 3 in 30° increments from the zenith angle. Detectors are designated with "o" or "d" depending on whether they are circularly symmetric or directional with respect to the primary electron beam. For example, they are denoted as SE/A2o or BE/AB3d. Using this notation, we classify images obtained with low-pass secondary electron detectors (Fountain detector) and high-pass backscattered electron detectors, and discuss their characteristics.