Depth of formation of a reflected soft x-ray beam under conditions of specular reflection

Over a wide range of glancing-incidence angles, bremsstrahlung from an x-ray tube was used to measure the reflection spectra of an Si-SiO2 system with different dioxide thickness near the Si L-2,L-3 ionization threshold. The angular dependence of the depth of formation of the reflected soft x-ray beam was determined experimentally and compared with that obtained from a theoretical analysis of the interaction between electromagnetic radiation and the surface of an isotropic solid. (C) 1998 American Institute of Physics.