Hardware Response Function of the Reflected Electron Detector and Contrast of the Chemical Composition of Samples in Scanning Electron Microscopy

Formulas are given for calculating the coefficient of backscattered electrons depending on the material (atomic number Z), i.e., the chemical composition of a sample, and the energy E_B of the primary irradiating electrons. The calculation of the detectable signal of reflected electrons is given depending on Z, E_B, and the response function F of semiconductor detectors and detectors based on microchannel plates (MCPs). The calculation results are compared with the experimentally measured ones. A comparative analysis of the contrast of images of the composition of samples obtained for different types of detectors at different E_B is performed. The results of the research are intended to serve practical users and experimenters in scanning electron microscopy.