Auger electron spectroscopy curve

For example, consider the dissociative adsorption of methane on a Ni(lOO) surface. If the experiment is performed above 350 K, methane dissociates into carbon atoms and hydrogen that desorbs instantaneously. Consequently, one determines the uptake by measuring (e.g. with Auger electron spectroscopy) how much carbon is deposited after exposure of the surface to a certain amount of methane. A plot of the resulting carbon coverage against the methane exposure represents the uptake curve. 

Comparing SIMS and SNMS depth profiles, deviations from the theoretical distribution of, for example, implanted species, are smaller in the case of the SNMS profile (see Figure 40.18). Effects of surface contaminations or oxides on the ionization probability are strong in SIMS, especially in the case of Ar primary ions, as well as the enhancement effect of the oxygen primary ions on the ionization probability. Variations in sputtering rate until a steady state is reached can be corrected in SNMS (see above) so that the SNMS curve corresponds best with the Auger electron spectroscopy (AES) curve [286]. 

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