Spectral processing for parallel recording of elemental maps.

Seven different one-, two-, or three-parameter analytic expressions were tested for their applicability to electron energy-loss spectral processing for mapping of atomic distributions in images of magnesium oxide crystals. Two-point two-parameter fits all provided indistinguishable results. Fine structure in the spectrum produced major quantitative inconsistencies for any given expression. This effect was exacerbated with the use of three-parameter expressions. Mass-thickness effects on the oxygen map of Mg0 were inconsequential up to a crystal thickness of 30 nm, but became dominant and unacceptable at a 50% increase in thickness above this. This observation can be explained by a specific single inelastic scatter coupled with any number of elastic scattering events.