QUANTITATIVE SURFACE-ANALYSIS OF LAYERED MATERIALS

The effects of concentration variation with depth, C(X), on the quantitative reduction of electron spectroscopic data is discussed. It is shown that when the concentration varies with depth, quantitation of the data is affected by the escape depth of the electron transitions chosen for quantitation. Therefore, accurate quantitation is impossible without knowledge of C(X). A Laplace transform method to determine C(X) from angle-resolved electron spectroscopic data is reviewed, along with potential problems caused by variation with angle of the escape depth of electrons in the solid, channeling, forward scattering, matrix corrections and surface roughness.