XRR - X-ray Reflectometry
When X-rays strike a surface at glancing incidence they can reflect
off the surface. However, if the surface is rough or covered by a film, then the X-ray
reflectivity of a surface can change. XRR takes advantage of this effect by measuring the
intensity of X-rays reflected from a surface as a function of angle. Thin films on a
surface can give rise to oscillations of the X-ray intensity with angle. XRR can provide
information on the thickness, roughness and density of thin films on a surface.