Quantitative Auger electron spectroscopy of silicides by extended matrix correction using dN(E)/dE spectra

Abstract

AbstractAn extended matrix correction procedure is proposed which considers effects created by different atomic densities, electron backscattering, electron attenuation and peak shapes. Asymmetry factors are introduced that reflect line shape changes of signals in compounds or alloys very well. From asymmetry factors a peak shape correction factor is determined. To overcome the uncertainties in correction for changing electron attenuation, a new method for calculation of λ is presented. The results are compared with experimental values and tested in matrix correction. The concentration ratios obtained are compared with results using inelastic mean free path lengths or attenuation depths determined by the methods of Penn. Tanuma et al., Tokutaka et al. and Seah and Dench in matrix correction. For the determination of concentration ratios from samples of unknown composition, an iteration procedure is introduced. The extended matrix correction is applied on silicides such as VSi2, V5Si3, V3Si, CrSi2, Cr3Si, MoSi2, Pd2Si and PtSi, yielding results which are accurate to 7%. The weight of the individual correction factors in the extended matrix correction procedure is discussed, dependent on experimental conditions and sample constituents. Without correction for matrix effects, erroneous results up to 30% can occur.