A comparative study of single crystal magnesium oxide and oxidised magnesium by auger electron spectroscopy

In a study by AES of the surfaces of single crystal magnesium oxide and magnesium after various stages of oxidation, it has been shown that Auger energy shifts are produced by surface charging. Recognition of the charging effects has enabled the peak in the low energy spectrum of magnesium oxide crystal to be assigned. The low energy secondary electron spectra of both MgO crystal and oxidised magnesium are complicated by the presence of extra features which arise from diffraction of true secondary electrons, and in particular for oxidised magnesium a cross-transition occurring at the metal-oxide interface. Oxidation studies of sodium also reveal transitions arising from a similar process.