Part A: Validity of Rutherford Scattering. Part B: A Monte-Carlo Technique for the calculation of keV ion back-scattering from metal surfaces.

Abstract

<p>Part A:</p> <p>The purpose of this report is to study the validity of the Rutherford Scattering Law. Both the angular and energy dependence of the . scattering cross-section are checked, also comparison between the absolute cross-section determined experimentally and the theoretical cross-section is made.</p> <p>Here we study the scattering of helium and oxygen ions with energies varying from 0.5 to 2.0 MeV from thin bismuth targets made by implanting 40 keV bismuth ions in low Z(silicon) substrate to doses of 10¹⁶ ions/cm². The implantation process was made on the Isotope Separator and the scattering experiments were made on the Van-de-Graff accelerator of the SSS branch of the AECL. The scattering angles considered here range from 90˚ to 160˚ and a special geometrical arrangement was used to enable us to measure the scattering angle accurately. Also the report contains a brief description of the different sources of errors during target preparation (implantations) and the scattering experiments.</p> <p>Part B:</p> <p>As an introduction to a larger study of ion bombardment phenomena on metal surfaces, we apply the Monte-carlo technique to calculate the range distribution and back-scattering of keV ions from metal surfaces. Lindhard theory is used to calculate both the ion-metal atom scattering and the electron stopping power. The program can be used over a wide range of reduced energies (.1 < ɛ < 30) limited only by the validity of the Lindhard theory. A sample calculation of hydrogen scattering from aluminum is presented.</p>