Advertisement

The Fresnel Method for the Characterisation of Interfaces

  • W. M. Stobbs
  • F. M. Ross
Part of the NATO ASI Series book series (NSSB, volume 203)

Abstract

We describe here the work we have been doing in Cambridge over the last few years on the development and application of the “Fresnel Method” for the study of interfaces. The accuracy to which the shape and magnitude of a local compositional inhomogeneity can be measured using this approach is often startlingly high and our aim now is to encourage others to start to use the approach. While there are still several aspects of the technique which, as we will describe below, can cause difficulties, we have now used it for a sufficient number of different types of materials problems to be confident that the method has a future in compositional analysis at a spatial resolution at, or approaching, the atomic level. Arguably the method is far from new though, as yet, we seem to be alone in making a systematic study of its breadth of application in the analysis of compositional changes at grain and phase boundaries and in man-made layer systems.

Keywords

Elastic Scattering Inelastic Scattering Specimen Thickness Boundary Segregation High Resolution Electron Microscopy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    J. N. Ness, W. M. Stobbs and T. F. Page, The detemination of the mean inner potential of grain boundary films in WC-Co composites by Fresnel techniques, in: Inst. Phys. Conf. Ser. 75, G. J. Tatlock, ed., Adam Hilger, Bristol, p. 523 (1985).Google Scholar
  2. 2.
    J. N. Ness, W. M. Stobbs and T. F. Page, A TEM Fresnel diffraction based method for characterising thin grain boundary and interfacial films, Philos. Mag. A 54: 679 (1986).Google Scholar
  3. 3.
    K. B Alexander, C. B. Boothroyd, E. G. Britton, F. M. Ross, C. S. Baxter and W. M. Stobbs, Methods for the assessment of layer orientation, interface step structure and chemical composition in GaAs/AlGaAs multilayers, in: Inst. Phvs. Conf. Ser. 78, A. G. Cullis, ed., Adam Hilger, Bristol, p. 195 (1987).Google Scholar
  4. 4.
    F. M. Ross, E. G. Britton, W. M. Stobbs, The application of Fresnel fringe contrast analysis to the measurement of composition profiles in GaAs/(AlGa)As heterostructures, in: EMAG’87 Analytical Electron Microscopy, G. W. Lorimer, ed., Inst. Metals, London, p. 205 (1988).Google Scholar
  5. 5.
    F. M. Ross and W. M. Stobbs, Interface aanalysis using elastic scattering in the Transmission electron microscope: Application to the oxidation of silicon, Surf. and Interface Anal., 12: 35 (1988).CrossRefGoogle Scholar
  6. 6.
    F. M. Ross and W. M. Stobbs, Study of composition changes across the Si/SiOx interface using Fresnel fringe contrast analysis, in: M. R. S. Proc. 105, G. Lucovsky and S. T. Pantelides, eds., M. R. S. Publications, Pittsburgh (1988).Google Scholar
  7. 7.
    W. M. Stobbs and F. M. Ross, The use of the Fresnel method for the study of localised composition changes at interfaces, in: EMAG ’87 Analytical Electron Microscopy, G. W. Lorimer, ed., Inst. Metals, London, p. 165 (1988).Google Scholar
  8. 8.
    C. B. Boothroyd, A. P. Crawley and W. M. Stobbs, The measurement of rigid body displacements using Fresnel fringe intensity methods, Philos. Mag. A54: 633 (1986).Google Scholar
  9. 9.
    F. M. Ross, The development and application of the Fresnel method, Ph.D. Thesis, Cambridge (1988).Google Scholar
  10. 10.
    W. O. Saxton, T. J. Pitt and M. Horner, Digital image processing: the SEMPER system, Ultramicrosc., 4: 343 (1979).CrossRefGoogle Scholar
  11. 11.
    P. A. Doyle and P. S. Turner, Relastivistic Hartree-Fock x-ray and electron scattering factors, Acta. Crystallogr. A 24: 390 (1968).Google Scholar
  12. 12.
    G. Radi, Complex lattice potentials in electron diffraction calculated for a number of crystals, Acta. Crvstallogr. A 26: 41 (1970).CrossRefGoogle Scholar
  13. 13.
    D. J. Smith, V. E. Cosslet and W. M. Stobbs, Atomic resolution with the electron microscope, Interdisc. Sci. Rev. 6: 155 (1981).Google Scholar
  14. 14.
    W. M. Stobbs, High resolution: direct or indirect?, Ultramicrosc., 9: 221 (1982).CrossRefGoogle Scholar
  15. 15.
    W. M. Stobbs and W. O. Saxton, Quantitative high resolution transmission electron microscopy: the need for energy filtering and the advantages of energy-loss imaging, J. Microsc. 151: 171 (1988).CrossRefGoogle Scholar
  16. 16.
    C. B. Boothroyd and W. M. Stobbs, The effects of contributions from energy loss electrons to “centre stop” high resolution images of (AlGa)As/GaAs interfaces, in: Inst. Phvs. Conf. Ser. 90, L. M. Brown, ed., Institute of Physics, Bristol, p. 237 (1987).Google Scholar
  17. 17.
    C. B. Boothroyd and W. M. Stobbs, The contribution of inelastically scattered electrons to high resolution images of (AlGa)As/GaAs heterostructures, Ultramicrosc., in press (1988).Google Scholar
  18. 18.
    M. J. Hytch and W. M. Stobbs, The effects of single electron and plasmon scattering on [100] and [010] images of YBa2Cu3O7.8, in: Inst. Phvs. Conf. Ser. 93. P. J. Goodhew and H. G. Dickinson, eds., Institute of Physics, Bristol, 2: 347 (1988).Google Scholar
  19. 19.
    M. J. Hÿtch and W. M. Stobbs, The relative effects of the Debye Waller factor and inelastic scattering on high resolution imaging of [100] and [010] orientations of YBa2Cu3O7-8, in: Proc. 46th Annual Meeting of EMSA G. W. Bailey, ed., San Francisco Press, San Francisco, p. 958 (1988)Google Scholar
  20. 20.
    S. H. Stobbs and W. M. Stobbs, Relative advantages and disadvantages of TEM and STEM for energy loss imaging, in: EMAG ’87 Analytical Electron Microscopy G. W. Lorimer, ed., Inst. Metals, London, p.111 (1988).Google Scholar
  21. 21.
    P. E. Batson, C. R. M. Grovenor, D. A. Smith and C. Wong, in: Proc. 41st Annual Meeting of EMSA, G. W. Bailey, ed., p. 154 (1983).Google Scholar
  22. 22.
    R. W. Devenish, D. J. Eaglesham, D. M. Maher and C. J. Humphreys, Nanometre scale lithography in the CTEM, in: Inst. Phvs. Conf. Ser. 93, P. J. Goodhew and H. G. Dickinson, eds., Institute of Physics, Bristol, 2: 391 (1988).Google Scholar
  23. 23.
    A. Bourret and C. Colliex, Combined HREM and STEM microanalysis of decorated dislocation cores, Ultramicrosc., 9: 183 (1982)CrossRefGoogle Scholar
  24. 24.
    CBED of Alloy Phases, J. Steeds and J. Mansfield, eds., Adam Hilger Ltd., Bristol (1984)Google Scholar
  25. 25.
    Convergent Beam Electron Diffraction, M. Tanaka and T. Terauchi, JEOL Ltd., Tokyo (1985)Google Scholar
  26. 26.
    P. Spellward, A new CBED method of composition determination in ternary semiconductors, in: Inst. Phys. Conf. Ser. 93, P. J. Goodhew and H. G. Dickinson, eds., Institute of Physics, Bristol, 2: 31 (1988).Google Scholar
  27. 27.
    H. Kakibayashi and F. Nagata, Composition dependence of equal thickness fringes in an electron microscope image of GaAs/AlGaAs multilayer, Jap. J. Appl. Phvs., 24: L905 (1985).CrossRefGoogle Scholar
  28. 28.
    H. Kakibayashi and F. Nagata, Simulation studies of a composition analysis by thickness fringe in an electron microscope image of GaAs/AlGaAs superstructure, Jap. J. Appl. Phys., 25: 1644 (1986).CrossRefGoogle Scholar
  29. 29.
    D. J. Eaglesham, C. J. D. Hetherington and C. J. Humphreys, Compositional studies of semiconductor alloys by bright field alactron microscope imaging of wedged crystals, in: M. R. S. Proc. 77, J. D. Dow and I. K. Schuller, eds., M. R. S. Publications, Pittsburgh, p. 473 (1987).Google Scholar
  30. 30.
    E. G. Bithell and W. M. Stobbs, Composition measurements in the GaAs/(Al, Ga)As system using dark field T. E. M. contrast, Philos. Mag., in press, (1989).Google Scholar
  31. 31.
    K. Fukushima, H. Kawakatsu and A. Fukami, Fresnel fringes in electron microscope images, J. Phys. D, 7: 257 (1974).CrossRefGoogle Scholar
  32. 32.
    D. R. Clarke, On the detection of thin intergranular flms in electron microscopy, Ultramicrosc., 4: 33 (1979).CrossRefGoogle Scholar
  33. 33.
    N. W. Jepps, T. F. Page and W. M. Stobbs, A method for the TEM characterisation of grain boundary films in ceramics, in: Inst. Phys. Conf. Ser. 61, M. J. Goringe, ed., Adam Hilger, Bristol, p. 453 (1981).Google Scholar
  34. 34.
    M. Rühle, E. Bischoff and O. David, The structure of grain boundaries in ceramics, Ultramicrosc., 14: 37 (1984)CrossRefGoogle Scholar
  35. 35.
    W. M. Stobbs, Electron microscopical techniques for the observation of cavities, J. Microsc. 116: 3 (1979).CrossRefGoogle Scholar
  36. 36.
    S. Iijima, High resolution electron microscopy of phase objects: Observation of small holes and steps on graphite crystals, Optik, 47: 437 (1977).Google Scholar
  37. 37.
    M. Rühle and S. L. Sass, The detection of the change in mean inner potential at dislocations in grain boundaries in NiO, Philos. Mag. A, 49: 759 (1984).Google Scholar
  38. 38.
    C. B. Boothroyd and W. M. Stobbs, Fresnel effects for grain boundary dislocations, Philos. Mag. A, L5: 49 (1984).Google Scholar
  39. 39.
    P. E. Donovan and W. M. Stobbs, A method for the mapping of localised displacement fields in boundaries, J. Microsc., 130: 361 (1983).CrossRefGoogle Scholar
  40. 40.
    P. E. Donovan and W. M. Stobbs, A computational assessment of a method for the mapping of localised displacement fields at boundaries, Ultramicrosc., 23: 119 (1987).CrossRefGoogle Scholar
  41. 41.
    L. A. Bursill, J. C. Barry and P. R. Hudson, Fresnel diffraction at {100} platelets in diamond: An attempt at defect structure analysis by high resolution by high resolutionphase contrast microscopy, Philos. Mag. A, 37: 789 (1978).CrossRefGoogle Scholar
  42. 42.
    H. Oppolzer, Electron microscopy of semiconductor devices and materials, in: Inst. Phvs. Conf. Ser. 93, P. J. Goodhew and H. G. Dickinson, eds., Institute of Physics, Bristol, 2: 73 (1988).Google Scholar
  43. 43.
    C. S. Baxter and W. M. Stobbs, The structural characterisation of multilayered Cu/NiPd films at the atomic level, in: Inst. Phys. Conf. Ser. 78 G. J. Tatlock, ed., Adam Hilger, Bristol, p. 387 (1985).Google Scholar
  44. 44.
    C. S. Baxter and W. M. Stobbs, A “phase transition” in fcc Cu/NiPd multilayers characterised by high resolution lattice imaging, Nature, 322: 814 (1986).CrossRefGoogle Scholar
  45. 45.
    K. Sato and W. M. Stobbs, Quantitative dark field image analysis of spinodal decomposition in Cu3-xMnxAl alloys, in: Inst. Phvs. Conf. Ser. 90, L. M. Brown, ed., Institute of Physics, Bristol, p. 253 (1988).Google Scholar
  46. 46.
    W-C. Shih, private communication.Google Scholar
  47. 47.
    K. M. Knowles and W. M. Stobbs, The structure of {111} age hardening precipitates in Al-Cu-Mg-Ag alloys, Acta Crystallog. B 44: 207 (1988).CrossRefGoogle Scholar
  48. 48.
    K. M. Knowles, F. M. Ross and W. M. Stobbs, Precipitate formation in Al-Cu-Mg-Ag alloys, in: EMAG ’87 Analytical Electron Microscopy, G. W. Lorimer, ed., Inst. Metals, London, p. 55 (1988).Google Scholar
  49. 49.
    K. Sato, private communication.Google Scholar
  50. 50.
    A. J. Bourdillon, W. M. Stobbs, K. Page, R. Home, C. J. Wilson, B. A. Ambrose, L. J. Turner and G. P. Tebby, A dual parallel and serial detection spectrometer for EELS, in: Inst. Phys. Conf. Ser. 78, G. J. Tatlock, ed., Adam Hilger, Bristol, p. 161 (1985).Google Scholar

Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • W. M. Stobbs
    • 1
  • F. M. Ross
    • 1
  1. 1.Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeUK

Personalised recommendations