Tomography of Three-Layer Structures in Scanning Electron Microscopy in the Backscattered Electron Detection Mode

The paper proposes a method for solving a three-dimensional tomography problem using data from a scanning electron microscope in the backscattered electron detection mode. Based on the assumption that the sample has a three-layer structure, analytical expressions were constructed for the dependence of the intensity of the detected signal on the chemical composition of the sample, the thickness of the layers, and the energy of the primary electrons. Based on the obtained analytical expressions, using the example of a three-layer (aluminium-gold-silicon) structure, the inverse problem of reconstructing the thicknesses of the aluminum and gold layers is solved in two different formulations, depending on the type of a priori information available about the structure of the sample.