Several methods can be used to determine the elemental composition and surface structure of solid materials. Among more accurate ones, there is a method of using the low energy ion scattering technique (LEIS). Owing to the sensitivity of this technique when applied to the topmost surface layers, it is considered an ideal method among other surface techniques. The LEIS technique supplies useful information about the composition, concentration and surface structure of metals and metal alloys. Mono-energetic ions such as helium with low energies are used to analyze surfaces. By using computer simulation, elements in solid bulk as well as on the surface of a solid body could be determined. In this study, the SABRE computer code was used for this purpose. The LEIS technique is based on energy transfer between incident ions and target atoms. It is necessary to have certain information such as the incident and azimuthal angles as well as the incident energy in order to perform this type of scattering. The application of the LEIS technique generates an energy spectrum, which was the purpose of the present work. This spectrum is achieved from simulation data which present certain peaks. Once the peaks are analyzed, masses of elements on the surface and hence the structure type could be determined by the energy difference between incident and scattered ion beam energies and the peak counts. The sample used in this project was Al- Pd- Mn quasicrystal. Three relatively clear peaks appeared for the sample representing consistent elements. The results proved that all the three elements, Al, Pd and Mn, were present on the surface.

26.3.2021