In thin crystals, an X-ray standing wave field is generated by the interference between the strong incident wave and the weak Bragg diffracted X-ray wave. Though the spatial modulation of the interference field is greatly reduced, the XSW method retains the same structural sensitivity as in thick perfect crystals diffracting dynamically. Because the diffraction curve from a thin crystal is broad, the XSW technique is much less sensitive to lattice imperfections. As examples, we demonstrate in this chapter how this technique can be applied to determine the “as-grown” and “externally switched” polarity in epitaxial thin films. With modern SR sources, the standing wave in an ultra-thin film of only 25 unit cells can be generated and utilized for precise structural investigation.
|Original language||English (US)|
|Title of host publication||The X-Ray Standing Wave Technique: Principles and Applications|
|Editors||Jorg Zengengahen, Alexander Kazimirov|
|Publisher||World Scientific Publishing Company|
|Number of pages||16|
|State||Published - Apr 15 2013|