Time of Flight - Elastic recoil detection analysis (ToF-ERDA) is a method used to analyse the composition of wall samples from fusion devices. All current analysing software for ToF-ERDA assumes that the target is perfectly flat which could create inaccuracies when rough surfaces are analysed. The aim of this project was to get a better understanding of how the roughness of samples from fusion devices affect the results from ToF-ERDA. To investigate this, three existing simulation softwares SIMNRA, TRIM and Potku were used. Programs were developed in order to use these to simulate three different targets with varying roughness, which were modelled as a combination of surfaces of different thicknesses. The results from which were put back into Potku where the differences between the targets could be noted. The study shows that it was possible to apply roughness to the already existing programs and showed similarities between the resulting depth profiles. When applying roughness, the concentration of surface elements decreased at the top of the layer but also went further into the sample. / Time of Flight - Elastic recoil detection analysis (ToF-ERDA) är en metod som används för att analysera kompositionen av prover av väggmaterial från fusionsreaktorer. Alla mjukvaror som används för att analysera datan från ToF-ERDA idag antar att provets yta är helt platt vilket skulle kunna innebära att felaktiga resultat erhålls när så ej är fallet. Målet med där här projektet var att undersöka och skapa en bättre förståelse för hur skrovligheten hos material från fusionsanordningar påverkar resultaten från ToF-ERDA. För att undersöka detta användes tre simulationsmjukvaror, SIMNRA, TRIM och Potku. Program skrevs för att använda dessa för att simulera tre olika material med olika stor skrovlighet, vilka modellerades som en kombination av material med olika tjockt ytskikt. Resultaten från dessa analyserades därefter i Potku där skillnaderna mellan materialen kunde noteras. Studien visar att det är möjligt att implementera ojämnhet i den simulationsprogram som finns idag och flera likheter mellan de resulterande djupprofilerna från de olika simulationsmetoderna uppmärksammades. När högre skrovlighet användes minskade koncentrationerna av ytelementen vid materialets topp men djupet som de når i materialet ökade. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

The interplay of nuclear fuel with fission products is key for safe and efficient nuclear power operation. The diffusion of volatile fission products in very heavy reactor fuel matrices was investigated by analysing Zirconium Dioxide and Uranium Nitride, implanted with different ions. The samples were implanted using the 350kV Ion Implanter available at Uppsala University. Zirconium Dioxide was implanted with Xenon, Krypton and Iron, and Uranium Nitride was implanted with Krypton and Zirconium. The samples were then analysed using Time of Flight Elastic Recoil Detection Analysis (ToF-ERDA), Rutherford Backscattering Spectrometry (RBS), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). After the implantation and analysis, the samples were annealed at different times and temperatures. The annealing times were predicted by solving Fick’s second law with numerical methods and using Stopping and Range of Ions in Matter (SRIM) as an initial guess. The results show that annealing times can be predicted by solving Fick’s second law, to first order, and that ion implantation effects the stoichiometry of the samples. Future improvements could include improvement of underlying physics in the annealing predictions, and more extensive measurements performed on a wider range of samples.