X-Ray Reflectivity (XRR)

X-ray reflectivity is a non-destructive, non-contact method to measure film thickness, interfacial roughness and density of films ranging from 20 Å to 1 mm total thickness. Films can be single or multilayer structures, and the thickness of individual layers can be determined in minutes, with no optical constant corrections required. The films can be epitaxial, polycrystalline or amorphous. The thickness of the film is measured from the periodicity of fringes, the density from the angle at which the intensity begins to drop and the roughness from the damping of the thickness fringes and rate of intensity decrease with angle. These are not affected by the crystallinity of the film.