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X-rays, interacting weakly with matters, have long been used as an essential characterization tool to study thestructure of bulk crystalline materials owing to the negligible multiple scattering and significant penetration depth.Recently, in the benefit of very intense X-rays sources, such as synchrotron radiations, it becomes possible to obtainsurface and/or interface information selectively. One experimental technique is using the grazing incidence geometry.X-rays are known to be totally reflected on the surface of flat substances and strongly attenuated at small incidentangles relative to the surface plane less than a critical angle.1) Murra et al. used this X-ray total reflection phenomenonto develop a new technique for the structures of crystal surfaces and overlayer interfaces.2) This method is referred toas the grazing incidence X-ray scattering (GIXS), and has been commonly used to analyze 'in-plane' crystal structuresin a range from a few nanometers to several hundred nanometers beneath the surface on solids in air. Theoretically,Vineyard4) described GIXS with a distorted-wave approximation in the kinematical theory of X-ray diffraction. The aimof this lecture is to describe systematically the basics of GIXS and some applications for the elucidation of the in-planeand out-of plane structures of the thin films of condensed mater.
References
1. R.W. James, The Optical Principles of the Diffraction of X-rays, OX Bow Press, Woodbrige, Conn., 1982, Chapter 4.
2. W.C. Marra, P. Eisenberger, A.Y. Cho, J. Appl. Phys. 50, 6927 (1979).
3. P.H. Fuoss, K.S. Liang, P. Eisenberger (1989), In Synchrotron Radiation Research: Advances in Surface Science, edited by R. Z. Bachrach. New York: Plenum.
4. G.H. Vineyard, Phys. Rev. B 26, 4146 (1982).
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