Diffractometry under grazing incidence
Diffractometry under grazing incidence ( grazing incidence diffraction , GID ) is a method for investigation of structures of thin layers. Either X-ray radiation ( English grazing incidence X-ray diffraction , GIXD ) or neutron radiation ( English grazing incidence neutron diffraction , GIND ) is diffracted .
description
It is characterized by a particularly flat angle of incidence of the X-ray radiation on the sample (α <3 °; seen from the surface of the sample). The aim is to examine the sample with the smallest possible penetration depth in order to obtain measurement data on thin layers without a large background . With the conventional theta / 2-theta method, due to the penetration depth of the X-ray radiation, information of up to one millimeter of the sample is obtained, i.e. to a large extent the properties of the substrate below . Due to the very flat angle of incidence of the X-rays at GIXRD, the layer volume covered by the X-rays is reduced. The evanescent wave penetrates the material only weakly. For even smaller angles (0–0.6 degrees), the surface of the thin layer can even be examined.
A related method is the small-angle diffraction under grazing incidence (GISAS).
literature
- Mario Birkholz, Paul F. Fewster, Christoph Genzel: Thin film analysis by X-ray scattering . Wiley-VCH, 2006, ISBN 3-527-31052-5 , pp. 148 ff . ( limited preview in Google Book search).