Energy spectra of electrons reflected from layered targets

Abstract

Here we consider backscattering of electrons with an initial energy from 10 keV to several MeV by plane-parallel sandwich targets. Using invariance principles, we obtain a formula describing the changes in the energy spectra of electrons reflected into a given solid angle. These changes occur with increasing thickness of films of different materials on substrates of finite and infinite thickness. We present methods for calculating the reflection and transmission function used in the above calculation. Repeating this method for each layer gives the spectra of electrons backscattered by multilayer targets. Comparison with experimental data shows that the theory developed adequately describes the process of electron backscattering. Our results indicate that the spectroscopy of nonelastically reflected electrons could be very useful forin situ nondestructive express analysis of depth profiles of multicomponent materials.