Grazing-incidence transmission X-ray scattering: surface scattering in the Born approximation


Lu, X.; Yager, K.G.; Johnston, D.; Black, C.T.; Ocko, B.M. "Grazing-incidence transmission X-ray scattering: surface scattering in the Born approximation" Journal of Applied Crystallography 2013, 46 165–172.
doi: 10.1107/S0021889812047887


We present a new x-ray scattering geometry for studying thin film nanostructures. By focusing the incident beam on the sample edge, we measure the sub-horizon scattering, which is not complicated by the refraction and multiple-scattering effects that plague conventional grazin-incidence scattering.


Determination of the three-dimensional order in thin nanostructured films remains challenging. Real-space imaging methods, including electron microscopies and scanning-probe methods, have difficulty reconstructing the depth of a film and suffer from limited statistical sampling. X-ray and neutron scattering have emerged as powerful complementary techniques but have substantial data collection and analysis challenges. This article describes a new method, grazing-incidence transmission small-angle X-ray scattering, which allows for fast scattering measurements that are not burdened by the refraction and reflection effects that have to date plagued grazing-incidence X-ray scattering. In particular, by arranging a sample/beam geometry wherein the scattering exits through the edge of the substrate, it is possible to record scattering images that are well described by straightforward (Born approximation) scattering models.