Determination of Copper in Uniformly-Doped Silicon Thin Films by Isotope-Dilution Inductively Coupled Plasma Mass Spectrometry

  • Published : 20010200

Abstract

Uniformly-doped silicon thin films were fabricated by ion beam sputter deposition. The thin films had four levels of copper dopant concentration ranging between 1 ${\times}$1019 and 1 ${\times}$ 1021 atoms/cm3 . Concentrations of Copper dopants were determined by the isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) to provide certified reference data for the quantitative surface analysis by secondary ion mass spectrometry (SIMS). The copper-doped thin films were dissolved in a mixture of 1 M HF and 3 M HNO3 spiked with appropriate amounts of 65 Cu. For an accurate isotope ratio determination, both the detector dead time and the mass discrimination were appropriately corrected and isobaric interference from SiAr molecular ions was avoided by a careful sample pretreatment. An analyte recovery efficiency was obtained for the Cu spiked samples to evaluate accuracy of the method. Uncertainty of the determined copper concentrations, estimated following the EURACHEM Guide, was less than 4%, and detection limit of this method was 5.58 ${\times}$ 1016 atoms/cm3.

References

  1. J. Electrochem. Soc. v.143 Chyan, M. R.;Chen, J. J.;Chien, H. Y.;Sees, J.;Hall, L.
  2. J. Electrochem. Soc. v.143 Jeon, J. S.;Raghavan, S.;Paeks, H. G.;Lowell, J. K.;Ali, L.
  3. Surface Science and Interface Analysis v.13 Grant, J. T.;Williams, P.;Fine, J.;Powell, C. J.
  4. Surface and Interface Analysis v.26 Homma, Y.(et al.)
  5. Secondary Ion Mass Spectrometry Wilson, R. G.;Stevie, F. A.;Magee, C. W.
  6. Analyst v.125 Park, C. J.;Kim, K. J.;Cha, M. J.;Lee, D. S.
  7. Anal. Chem. v.65 Beary, E. S.;Paulsen, P. J.
  8. Metrologia v.35 Papadakis, I.;Taylor, P. D. P.;de Bievre, P.
  9. Analyst v.121 Park, C.
  10. J. Anal. At. Spectrom. v.13 Vanhaecke, F.;De Wannemacker, G.;Moens, L.;Dams, R.;Latkoczy, C.;Prohaska, T.;Stingeder, G.
  11. J. Anal. At. Spectrom. v.14 Muniz, C. S.;Marchante Gayon, J. M.;Garcia Alonso, I.;Sanz-Medel, A.
  12. J. Anal. At. Spectrom. v.14 Valles Mota, J. P.;Ruiz Encinar, J.;De la Campa, M. R. F.;Garcia Alonso, J. I.;Sanz-Medel, A.
  13. Quantifying Uncertainty in Analytical Measurement EURACHEM