Electron probe X-ray microanalysis of coatings

Monte-Carlo simulations were applied to electron probe X-ray microanalysis of thin coatings on a bulk material. The X-ray signal from the film and its lateral extent as a function of film thickness, primary beam energy and angle of incidence were calculated. All contributions to the measured total X-ray signal were taken into account. These are: a) The signal induced by the primary electron beam. b) The signal induced by backscattering, considered both within the film and the substrate. c) The signal induced by characteristic and continuous X-rays, created within the substrate by incident and backscattered electrons, which ionise the atoms of the film in their way out of it.