Electron inelastic mean free path measured by elastic peak electron spectroscopy for 24 solids between 50 and 3400 eV

In the present study, we prepared clean surfaces of polycrystalline Mn 3 Si, MnSi, and Mn 11 Si 19 by fracturing them in a spectrometer under an ultrahigh vacuum, and then attempted to construct a calibration curve for a quantitative XPS analysis by measuring these clean surfaces. We ensured that there were no C 1s and O 1s peaks in the survey XPS spectra for the fractured surfaces. In the case of Mn 11 Si 19 , a positive chemical shift in the binding energy of the Mn 2p level was observed, whereas a slight negative shift in the binding energy of the Si 2p level was observed in the cases of MnSi and Mn 3 Si. The spectral intensity ratios of Mn 3p to Si 2p and Mn 3s to Si 2p were proportional to the atomic ratio of Mn to Si, indicating that these relationships could be used as the calibration curve. On the other hand, no linear relationship was observed for the ratio of Mn 2p to Si 2p.

Section: Resultsmentioning

confidence: 99%

Experimental calibration curve for quantitative XPS analysis constructed from in situ fractured polycrystalline manganese silicide surfaces

Ohtsu

Oku

Shishido

et al. 2012

“…Werner et al 20,21 determined IMFPs from EPES experiments for 24 elemental solids (Be, C, Mg, Al, Si, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Ge, Mo, Pd, Ag, Te, Ta, W, Pt, Au, Pb and Bi) and energies between 50 and 3400 eV. They also fitted the Bethe equation (Eqn (5)) to their IMFPs using Fano plots and reported the resulting values ofˇand for each fit.…”

Section: Comparison With Epes-imfps Of Werner Et Almentioning

confidence: 99%

“…19 are generally less than the corresponding values of TPP . This result may be due in part to the different lowerenergy limits used in the fits of Eqn (5) Werner et al 20,21 report the 'uncertainties' in their determinations ofˇfrom their fits of Eqn (5) to their Fano plots. For the 11 solids common to both investigations, these uncertainties ranged from 8.7 to 36.4% (as indicated in Fig.…”

Section: Comparison With Epes-imfps Of Werner Et Almentioning

confidence: 99%

Experimental determination of electron inelastic mean free paths in 13 elemental solids in the 50 to 5000 eV energy range by elastic‐peak electron spectroscopy

Tanuma

Shiratori

Kimura

et al. 2005

140

120

We have determined electron inelastic mean free paths (IMFPs) in C (graphite), Si, Cr, Fe, Cu, Zn, Ga, Mo, Ag, Ta, W, Pt and Au by elastic-peak electron spectroscopy (EPES) using Ni as a reference material for electron energies between 50 and 5000 eV. These IMFPs could be fitted by the simple Bethe equation for inelastic electron scattering in matter for energies from 100 to 5000 eV. The average root-mean-square (RMS) deviation in these fits was 9%. The IMFPs for Si, Cr, Fe, Cu, Ag, Ta, W, Pt and Au were in excellent agreement with the corresponding values calculated from optical data for energies between 100 and 5000 eV. While the RMS differences for graphite and Mo in these comparisons were large (27 and 17%, respectively), the average RMS difference for the other 11 elements was 11%. Similar comparisons were made between our IMFPs and values obtained from the TPP-2M predictive equation for energies between 100 and 5000 eV, and the average RMS difference for the 13 solids was 10.7%; in these comparisons, the RMS differences for Ta and W were relatively large (26% for each). A correction for surface-electronic excitations was calculated from a formula of Werner et al.; except for Si and Ga, the average correction was 5% for energies between 150 and 5000 eV. The satisfactory consistency between the IMFPs from our EPES experiments and the corresponding IMFPs computed from optical data indicates that the uncertainty of these IMFPs is about 11% for electron energies between 100 and 5000 eV. Similar comparisons with IMFPs from the EPES experiments of Werner et al. showed a consistency of 8% for energies between 200 and 5000 eV.

“…For the ordinary XPS conditions, the penetration depth is very deep (from about 200 nm for Al K α to 2 µm for 3600 eV) when compared with the TR conditions. The escape depth was estimated from IMFP [7,8] www.interscience.wiley.com/journal/sia by taking into account the emission angle in the experimental geometry. The effect of elastic electron scattering was neglected.…”

Section: Resultsmentioning

confidence: 99%

High‐energy total reflection X‐ray photoelectron spectroscopy for polished iron surface

Nagoshi¹,

Kawano²,

Makiishi³

et al. 2008

Total reflection (TR) XPS has been applied to a mirror-polished iron sheet using incident X-ray with the energy range of 1800-3600 eV from synchrotron radiation. XPS spectra measured under the TR conditions show remarkably low background intensity and the relative background intensity becomes lower as the photon energy of incident X-ray increases. These results are explained qualitatively by means of shallow penetration depth of grazing incident X-rays and rather deep escape depth of high-energy photoelectrons. XPS spectra have been recorded under ordinary XPS geometry using X-rays with the same energy range. These spectra are compared with TRXPS, and background spectra are extracted and used for background subtraction for ordinary XPS spectra.