Meaning
Computational model predicts the spatial distribution of electron scattering events within a solid target. Performing an interaction volume simulation helps microscopists understand the depth and width of the signal generation zone. This knowledge is essential for interpreting the chemical data obtained from energy dispersive spectroscopy.
Monte Carlo Algorithm
Random walks of individual electrons are calculated based on the probability of elastic and inelastic scattering. Each step in the interaction volume simulation accounts for energy loss as the electron moves through the atomic lattice. The software aggregates thousands of these trajectories to visualize the pear shaped region of excitation.
This visualization shows how the beam spreads as it penetrates deeper into the material.
Spatial Resolution
Electron energy and atomic number of the sample determine the physical size of the excited region. In an interaction volume simulation, increasing the acceleration voltage expands the volume and reduces the ability to resolve small features. This effect limits the accuracy of phase identification in nanostructured materials.
Elemental Depth
Characteristic x-rays emerge from a different depth than secondary electrons. The simulation identifies the specific layer from which each signal type originates. Accurate depth information prevents the misinterpretation of substrate signals as surface coating data.
