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 _2,3 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. Fiz. Tverd. Tela (St. Petersburg) 40, 1360–1363 (July 1998)