Advertisement

Inorganic Materials

, Volume 54, Issue 14, pp 1417–1420 | Cite as

Electron Probe X-Ray Analysis of Nanofilms at Off-Normal Incidence of the Electron Beam

  • S. A. DarznekEmail author
  • V. B. Mityukhlyaev
  • P. A. Todua
  • M. N. FilippovEmail author
ANALYSIS OF SUBSTANCES
  • 6 Downloads

Abstract

The frontier of the electron probe X-ray spectral method in the determination of trace metal quantities on a silicon substrate is studied. The experimental data are acquired for ultrathin chromium films on a silicon substrate. It is shown that the signal-to-noise ratio significantly increases at a noticeable sample inclination (80°), which allows one to determine an extremely low (available by this approach) chromium content. The calibration curve for the inclined sample position is plotted using the Monte Carlo method. The surface concentration of chromium atoms (2.2 ± 0.4) × 1014 cm–2 and the chromium detection limit (5 × 1013 cm–2) are measured under the given experimental conditions. For the electron probe X-ray microanalysis of bulk samples, it is a record value. The equivalent weight of chromium at the aforementioned surface concentration is approximately 4 × 10–18 g. The proposed technique requires no changes in the design of the device to be applied.

Keywords:

electron probe X-ray analysis nanofilms detection limit chromium silicon substrate 

Notes

ACKNOWLEDGMENTS

This work was supported by the Russian Science Foundation (agreement no. 14-19-01652 from June 27, 2014).

REFERENCES

  1. 1.
    Opila, R.L. and Eng, J., Jr., Thin films and interfaces in microelectronics: composition and chemistry as function of depth, Prog. Surf. Sci., 2002, vol. 69, no. 4, pp. 125–163.CrossRefGoogle Scholar
  2. 2.
    Podgornyi, D.A., Smetyukhova, T.N., and Irzhak, A.V., Determination of the thickness of ultrathin films by using Auger electron spectroscopy, Zavod. Lab., Diagn. Mater., 2012, vol. 78, no. 8, pp. 33–36.Google Scholar
  3. 3.
    Senoner, M. and Unger, W.E.S., SIMS imaging of the nanoworld: applications in science and technology, J. Anal. At. Spectrom., 2012, vol. 27, no. 7, pp. 1050–1068.CrossRefGoogle Scholar
  4. 4.
    Chu, W.K. and Liu, J.R., Rutherford backscattering spectrometry: reminiscences and progresses, Mater. Chem. Phys., 1996, vol. 46, nos. 2–3, pp. 183–188.Google Scholar
  5. 5.
    Campos, C.S., et al., Thickness determination of ultra-thin films on Si substrates by EPMA, Microchim. Acta, 2004, vol. 145, no. 1–4, pp. 13–17.Google Scholar
  6. 6.
    Procop, M. et al., Electron probe microanalysis (EPMA) measurement of thin-film thickness in the nanometre range, Anal. Bioanal. Chem., 2002, vol. 374, no. 4, pp. 631–634.CrossRefGoogle Scholar
  7. 7.
    Llovet, X. and Merlet, C. Electron probe microanalysis of thin films and multilayers using the computer program XFILM, Microsc. Microanal., 2010, vol. 16, no. 1, pp. 21–32.CrossRefGoogle Scholar
  8. 8.
    Bakaleinikov, L.A. et al., Depth profiling of semiconductor structures by x-ray microanalysis using the electron probe energy variation technique, Semiconductors, 2009, vol. 43, no. 4, pp. 544–549.CrossRefGoogle Scholar
  9. 9.
    Popova, T.B. et al., Electron probe microanalysis of heterostructures with nanolayers, Semiconductors, 2011, vol. 45, no. 2, pp. 260–264.CrossRefGoogle Scholar
  10. 10.
    Gavrilenko, V.P. et al., Electron probe measurements of oxide film thickness on silicon surfaces, Meas. Tech., 2015, vol. 58, no. 9, pp. 953–957.CrossRefGoogle Scholar
  11. 11.
    Tsuji, K., Grazing-exit electron probe x-ray microanalysis (GE-EPMA): fundamental and applications, Spectrochim. Acta, Part B, 2005, vol. 60, no. 11, pp. 1381–1391.CrossRefGoogle Scholar
  12. 12.
    Wendt, M., Krajewski, T., and Bimberg, R., Detection of thin surface films by electron beam microanalysis. A comparison between wavelength-dispersive and energy-dispersive microprobes, Phys. Status Solidi A, 1976, vol. 36, no. 1, pp. 253–261.CrossRefGoogle Scholar
  13. 13.
    Pouchou, J.L., Pichoir, F., and Boivin, D., Further improvements in quantitation procedures for X-ray microanalysis, Proc. XII Int. Symp. on X-Ray Optics and Microanalysis, Cracow: Acad. Min. Metall., 1990, pp. 52–59.Google Scholar
  14. 14.
    Wendt, M., Electron probe microanalysis of thin films at variable angle of incidence, Fresenius’ J. Anal. Chem., 1991, vol. 340, pp. 193–196.CrossRefGoogle Scholar
  15. 15.
    Joy, D.C., Monte Carlo Modeling for Electron Microscopy and Microanalysis, New York: Oxford Univ. Press, 1995.Google Scholar
  16. 16.
    Reimer, L. and Krefting, E.R., The effect of scattering models on the result of Monte-Carlo calculations, Proc. Workshop “Use of Monte Carlo Calculations in Electron Probe Microanalysis and Scanning Electron Microscopy,” Gaithersburg, Maryland, October 1–3, 1975, Washington: US Govt. Print. Off., 1976, no. 460, pp. 45–60.Google Scholar
  17. 17.
    Llovet, X. et al., Cross sections for inner-shell ionization by electron impact, J. Phys. Chem. Ref. Data, 2014, vol. 43, no. 1, art. ID 013102.CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Inc. 2018

Authors and Affiliations

  1. 1.Research Center for Studying the Properties of Surfaces and VacuumMoscowRussia
  2. 2.Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of SciencesMoscowRussia

Personalised recommendations