Energy reflection by back-scattering and sputtering: Total yields and angular distribution.

Abstract

The energy reflection coefficient—total yields and angular distributions—have been calculated by solving the transport equation for the average kinetic energy flux. The energy flux transported by projectiles and by recoils were evaluated separately, thus the back-scattering and sputtering contributions to the reflected energy were obtained. We have considered an infinite medium of stopping material and neglected the electronic energy loss as well as crystalline effects. The introduction of a power scattering law leads to the reduction of the integral equation for the energy flux to an algebraic system of equations for the spatial moments. An analytical treatment to evaluate the energy flux carried by the projectiles is also included. Good agreement was found between our theory and experiment, in particular with recently reported angular distributions of the reflected energy. A special aspect of this work lies in the use of a synthetic kernel to represent the anisotropy of scattering in the laboratory system of co-ordinates.