This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
 

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X-ray reflectivity can be employed to measure the thickness of films, e.g. ALD and MBE-deposited layers, in order to adjust growth rates. In this technique, monochromatic X-rays reflected from the sample surface at low incident angles are measured and analyzed with a typical accuracy of ≤1 nm for layer thicknesses between ~2 and 500 nm. To obtain the thickness of a layer, the interference of the X-rays reflected from the surface of the layer and the X-rays reflected from the interface between the layer and substrate is measured in the form of intensity oscillations. The oscillation separation (Δθ) is given by,

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where,
         λ -- The X-rays' wavelength,
         t -- The thickness of the layer.