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Orientation contrast imaging of microstructures in rocks using forescatter detectors in the scanning electron microscope

Published online by Cambridge University Press:  05 July 2018

David J. Prior ,
Patrick W. Trimby ,
Ursula D. Weber  and
David J. Dingley
David J. Prior
Affiliation:
Department of Earth Sciences, Liverpool University, L69 3BX, UK
Patrick W. Trimby
Affiliation:
Department of Earth Sciences, Liverpool University, L69 3BX, UK
Ursula D. Weber
Affiliation:
Department of Earth Sciences, Liverpool University, L69 3BX, UK
David J. Dingley
Affiliation:
Department of Physics, University of Bristol, UK
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Abstract

We have developed a system using ‘forescatter detectors’ for backscattered imaging of specimen surfaces inclined at 50–80° to the incident beam (inclined-scanning) in the SEM. These detectors comprise semiconductor chips placed below the tilted specimen. Forescatter detectors provide an orientation contrast (OC) image to complement quantitative crystallographic data from electron backscatter patterns (EBSP). Specimens were imaged using two detector geometries and these images were compared to those collected with the specimen surface normal to the incident beam (normal-scanning) using conventional backscattered electron detector geometries and also to an automated technique, orientation imaging microscopy (OIM). When normal-scanning, the component of the BSE signal relating to the mean atomic number (z) of the material is an order of magnitude greater than any OC component, making OC imaging in polyphase specimens almost impossible. Images formed in inclined-scanning, using forescatter detectors, have OC and z-contrast signals of similar magnitude, allowing OC imaging in polyphase specimens.

OC imaging is purely qualitative, and by repeatedly imaging the same area using different specimen-beam geometries, we found that a single image picks out less than 60% of the total microstructural information and as many as 6 combined images are required to give the full data set. The OIM technique is limited by the EBSP resolution (1–2°) and subsequently misses a lot of microstructural information. The use of forescatter detectors is the most practical means of imaging OC in tilted specimens, but it is also a powerful tool in its own right for imaging microstructures in polyphase specimens, an essential asset for geological work.

Keywords

contrast imagesscanning electron microscopybackscattered electrons
Type
Mineralogy
Information
Mineralogical Magazine , Volume 60 , Issue 403 , December 1996 , pp. 859 - 869
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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References

Adams, B.L., Wright, S.I. and Kunze, K. (1993) Metall. Trans. 24A, 819-30.CrossRefGoogle Scholar
Alam, M.N., Blackman, M. and Pashley, D.W. (1954) Proc. Roy. Soc. 222, 224-42.Google Scholar
Bishop, H.E. (1974) In Quantitative Scanning Electron Microscopy (D.B. Holt, M.D. Muir, Boswarva, I.M. and Grant, P.R., eds). Academic Press, New York.Google Scholar
Burnley, P., Green, H.W. II. and Prior, D.J. (1991) J. Geophys. Res. 96 425–43.CrossRefGoogle Scholar
Coates, D.G. (1967) Philos. Mag. 16, 1179-84. Davidson, D.L. (1984) Int. Metal. Rev. 29 75–95.Google Scholar
Day, A. (1993) PhD thesis, University of Bristol. Dingley D.J. and Randle, V. (1992) J. Mater. Sci. 27, 4545-66.Google Scholar
Dingley, D.J. (1981) Scanning Electron Microscopy, 1981-IV, 273-86.Google Scholar
Dingley, D.J. (1984) Scanning Electron Microscopy, 1984-11, 569-75.Google Scholar
Dingley, D.J. and Baba-Kishi (1990) Microscopy and Analysis May, 35–7.Google Scholar
Fynn, G.W. and Powell, W.J.A. (1979) The Cutting and Polishing of Electro-optic Materials. Adams Hilger, London.Google Scholar
Goldstein, J.I., Newbury, D.E., Echlin, P., Joy, D.C., Fiori, C. and Lifshin, E. (1981) Scanning Electron Microscopy and X-Ray Analysis. Plenum Press.Google Scholar
Gopinath, . (1974) In Quantitative Scanning Electron Microscopy (D.B. Holt, M.D. Muir, Boswarva, I.M. and Grant, P.R., eds). Academic Press, New York.Google Scholar
Hall, M.G. and Lloyd, G.E. (1981) Amer. Mineral 66, 362-8.Google Scholar
Hirsch, P.B., Howie, A. and Whelan, M.J. (1962) Philos. Mag. 7, 2095–100.CrossRefGoogle Scholar
Hirsch, P.B., Howie, A., Nicholson, R.B., Pashley, D.W. and Whelan, M.J. (1965) Electron Microscopy of Thin Crystals. Butterworths. London.Google Scholar
Joy, D.C., Newbury, D.E. and Davidson, D.L. (1982) J. Appl. Phys. 55, R81–R22.CrossRefGoogle Scholar
Joy, D.C. (1974) In Quantitative Scanning Electron Microscopy (D.B. Holt, M.D. Muir, Boswarva, I.M. and Grant, P.R., eds). Academic Press, New York.Google Scholar
Kanter, H. (1957) Ann. Phys. 20, 144–66.CrossRefGoogle Scholar
Krinsley, D.H., Pye, K. and Kearsley, A.T. (1983) Geol. Mag. 120, 109-14.CrossRefGoogle Scholar
Kunze, K., Heidelbach, F., Wenke, H-R. and Adams, B.L. (1995) In Textures of Geological Materials (Bunge, H.J., Siegesmunde, S., Skrotski, W. and Weber, K., eds) DGM Informationsgesellschaft MbH.Google Scholar
Law, R.D., Schmid, S.M. and Wheeler, J. (1990) J. Struct. Geol. 12, 29–45.CrossRefGoogle Scholar
Lloyd, G.E. (1985) In Applications of Electron Microscopy in the Earth Sciences (J.C. White ed.) Mineral. Assoc. Can. Short Course 11, 151–88. Lloyd, G.E. and Hall, M.G. (1981) Tectonophysics 78, 687-98.Google Scholar
Lloyd, G.E. and Knipe, R.J. (1992) J. Struct. Geol 14, 127-43.CrossRefGoogle Scholar
Lloyd, G.E. (1987) Mineral. Mag. 51, 3–19.CrossRefGoogle Scholar
Lloyd, G.E. (1995) In Textures of Geological Materials (H.J. Bunge, S. Siegesmunde, W. Skrotski and K. Weber, eds) DGM Informationsgesellschaft MbH, Lloyd, G.E., Ferguson, C.C. and Law, R.D., (1987) Tectonophysics 135, 243–9.Google Scholar
Lloyd, G.E., Law, R.D., Mainprice, D. and Wheeler, J. (1992) J. Struct. Geol 14, 1079-100.CrossRefGoogle Scholar
Lloyd, G.E., Schmidt, N.H., Mainprice, D. and Prior, D.J. (1991) Mineral. Mag. 55, 331–45.CrossRefGoogle Scholar
Loretto, M.H. (1994) Electron Beam Analysis of Materials. Chapman and Hall, London.Google Scholar
Mainprice, D., Lloyd, G.E. and Casey, M. (1993) J. Struct. Geol., 15, 1169–87.CrossRefGoogle Scholar
Murata, K. (1973) SEM / 1973 IIT Research Institute, Chicago, Illinois, 268.Google Scholar
Murata, K. (1974) J. Appl, Phys., 45, 4110.CrossRefGoogle Scholar
Newbury, D.E. and Yakowitz H. (1976) National Bureau of Standards Spec. Pub., 460 (Heinrich, K.F.J., Newbury, D.E. and Yakowitz, H., eds) Washington, DC, 15,Google Scholar
Newbury, D.E., Yakowitz, H. and Yew, N. (1974) Appl. Phys. Lett., 24, 98.CrossRefGoogle Scholar
Newbury, D.E., Joy, D.C., Echlin, P., Fiori, C.E. and Goldstein, J.I. (1973) Advanced Scanning Electron Microscopy and X-Ray Microanalysis. Plenum Press, New York.Google Scholar
Oatley, C.W. (1972) The Scanning Electron Microscope. Cambridge University Press.Google Scholar
Prior, D.J. (1988) PhD thesis, University of Leeds.Google Scholar
Prior, D.J. (1993) Contrib. Mineral. Petrol., 113, 545–56.CrossRefGoogle Scholar
Prior, D.J., Knipe, R.J. and Handy, M.R. (1990) In Deformation Mechanisms, Rheology and Tectonics (Knipe, R.J. and Rutter, E.H., eds) Spec. Publ. Geol. Soc. Lond., 54, 309-20.Google Scholar
Randle, V. (1992) Microtexture Determination and its Applications. The Institute of Materials. London. Schmidt, N.H. and Olesen, N.0. (1989) Canad. Mineral., 27, 15–22.Google Scholar
Venables, J.A. and Harland, C.J. (1972) Philos. Mag., 27, 1193-200.CrossRefGoogle Scholar
Wells, O.C. (1974) Scanning Electron Microscopy. McGraw Hill, New York.Google Scholar
White, S.H., Shaw, H.F. and Huggett, J.M. (1984) J. Sed. Petr., 54, 487-94.Google Scholar
Wilkinson, A.J., Anstis, G.R., Czernuska, J.T., Long, N.J. and Hirsch, P.B. (1993) Philos. Mag. A. Phys. Cond. Matt. Defects and Mechanical Properties, 68, 59–80.Google Scholar