Abstract The angular dependences of photoemission are measured in Bragg diffraction of X‐rays on germanium and silicon crystals covered with amorphous layers of various thickness. The function K(z) – the integral of electron escape probability versus generation depth – is obtained from the experimental data. The escape depth is found to be substantially lower than the estimates often used whereas K(z) is satisfactorily described by Liljequist's theory. In the photoeffect technique, the depth of the explored layer depends on the primary‐to‐secondary electron recording efficiency ratio. The capabilities of two methods of deep scanning – by changing the initial energy of electrons by a variation of the radiation wavelength and by means of the escape energy selection of electrons – are compared.