Electron Probe X-Ray Analysis of Nano-Films at Off-Normal Incidence of the Electron Beam
Abstract
The frontier of electron probe x-ray method in determination of the trace quantities of metal on a silicon substrate is studied. Experimental data are obtained for ultra-thin chromium films on a silicon substrate. It is shown that the signal - noise ratio significantly increases at a strong inclination of the sample (80°) which provides determination of extremely low (for this method) chromium content. Calibration curve for inclined sample position is obtained using Monte Carlo method. Surface concentration of chromium atoms (2.2 ± 0.5) × 1014 cm-2 and chromium detection limit (5 × 1013 cm-2) are determined experimentally for the given configuration of the experiment. For electron-probe microanalysis of bulk samples this is a record value. The equivalent mass of chromium at aforementioned value of the surface concentration is approximately 4 × 10-18 g. Implementation of the method does not require changes in the of the device design.
About the Authors
S. A. Darznek
Научно-исследовательский центр по изучению свойств поверхности и вакуума
Russian Federation
Russian Federation
V. B. Mityukhlyaev
Научно-исследовательский центр по изучению свойств поверхности и вакуума
Russian Federation
Russian Federation
P. A. Todua
Научно-исследовательский центр по изучению свойств поверхности и вакуума
Russian Federation
Russian Federation
M. N. Filippov
Научно-исследовательский центр по изучению свойств поверхности и вакуума; Институт общей и неорганической химии им. Н. С. Курнакова РАН
Russian Federation
Russian Federation
References
1. Opila R. L., Eng J. Jr. Thin films and interfaces in microelectronics: composition and chemistry as function of depth / Prog. Surf. Sci. 2002. Vol. 69. N 4. P. 125 - 163.
2. Подгорный Д. А., Сметюхова Т. Н., Иржак А. В. Определение толщин сверхтонких пленок методом электронной Оже-спектроскопии / Заводская лаборатория. Диагностика материалов. 2012. Т. 78. № 8. С. 33 - 36.
3. Senoner M., Unger W. E. S. SIMS imaging of the nanoworld: applications in science and technology / J. Anal. Atom. Spectrom. 2012. Vol. 27. N 7. P. 1050 - 1068.
4. Chu W. K., Liu J. R. Rutherford backscattering spectrometry: reminiscences and progresses / Mat. Chem. Phys. 1996. Vol. 46. N 2 - 3. P. 183 - 188.
5. Campos C. S. et al. Thickness determination of ultra-thin films on Si substrates by EPMA / Microchim. Acta. 2004. Vol. 145. N. 1 - 4. P. 13 - 17.
6. Procop M. et al. Electron probe microanalysis (EPMA) measurement of thin-film thickness in the nanometre range / Anal. bioanal. Chem. 2002. Vol. 374. N 4. P. 631 - 634.
7. Llovet X., Merlet C. Electron probe microanalysis of thin films and multilayers using the computer program XFILM / Microsc. Microanal. 2010. Vol. 16. N 1. P. 21 - 32.
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. N 4. P. 544 - 549.
9. Popova T. B. et al. Electron probe microanalysis of heterostructures with nanolayers / Semiconductors. 2011. Vol. 45. N 2. P. 260 - 264.
10. Gavrilenko V. P. et al. Electron probe measurements of oxide film thickness on silicon surfaces / Measur. Tech. 2015. Vol. 58. N 9. P. 953 - 957.
11. Tsuji K. Grazing-exit electron probe X-ray microanalysis (GE-EPMA): Fundamental and applications / Spectrochim. Acta. Part B: Atomic Spectroscopy. 2005. Vol. 60. N. 11. P. 1381 - 1391.
12. Wendt M., Krajewski T., Bimberg R. Detection of thin surface films by electron beam microanalysis. A comparison between wavelength-dispersive and energy-dispersive microprobes / Physica Status Solidi (A). 1976. Vol. 36. N 1. P. 253 - 261.
13. Pouchou J. L., Pichoir F., Boivin D. Further improvements in quantitation procedures for X-ray microanalysis / Proceedings of the XII International Symposium on X-Ray Optics and Microanalysis. 1990. P. 52 - 59.
14. Wendt M. Electron probe microanalysis of thin films at variable angle of incidence / Fresenius J. Anal. Chem. 1991. Vol. 340. P. 193 - 196.
15. Joy D. C. Monte Carlo Modeling for Electron Microscopy and Microanalysis. - N.Y.: Oxford Univ. Press, 1995. - 216 p.
16. Reimer L., Krefting E. R. The effect of scattering models on the result of Monte-Carlo calculations / Use of Monte Carlo calculations in electron probe microanalysis and scanning electron microscopy: proceedings of a workshop held at the National Bureau of Standards, Gaithersburg, Maryland, October 1 - 3, 1975. - US Dept. of Commerce, National Bureau of Standards: for sale by the Supt. of Docs., US Govt. Print. Off., 1976. N 460. P. 45 - 60.
17. Llovet X. et al. Cross sections for inner-shell ionization by electron impact / J. Phys. Chem. Ref. Data. 2014. Vol. 43. N 1. P. 013102 - 013105.
Review
For citations:
Darznek S.A., Mityukhlyaev V.B., Todua P.A., Filippov M.N. Electron Probe X-Ray Analysis of Nano-Films at Off-Normal Incidence of the Electron Beam. Industrial laboratory. Diagnostics of materials. 2017;83(9):5-9. (In Russ.)
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