The physical basis for x-ray induced secondary electron emission in the range of the absorption edges is described. Applications of this principle for nondestructive composition determination and for nanometer resolved quantitative composition depth profiling are illustrated. A new commercial type of scientific instrument is presented which can be used for this new technique, and for almost all methods that require x-ray photon beam probing.

All the methods described in this paper are based on the same phenomenon, chat is, the phenomenon of the jump-like increase of x-ray photoabsorption in the vicinity of the x-ray absorption edges of the chemical elements of the sample.