X-ray microanalysis of a coated nonconductive specimen: Monte Carlo simulation

The microanalysis of nonconductive specimen in a scanning electron microscope is limited by charging effects. Using a charge density model for the electric field buildup in a nonconductive specimen irradiated by electrons, a Monte Carlo simulation method has been applied to alumina (Al2O3). The results show a change in the depth distribution for characteristic and bremsstrahlung X-ray, phi(rhoz) curves, and psi(rhoz) curves (with absorption) for both elements' Kalpha lines. The influence of the electric field on the measured X-ray intensity is shown. The dependency of this influence by the three parameters, electron energy, X-ray energy, and charge density, is clarified.