Sputter-deposition of ultra-thin film stacks from EUROFER97 and tungsten : characterisation and interaction with low-energy D and He ions

We have sputter-deposited stacks of ultrathin layers from EUROFER97 and tungsten on silicon substrates. Ion beam analysis techniques are used for composition characterisation and microscopy methods are employed for structural examination. The films are subsequently studied by time-of-flight low-energy ion scattering (ToF-LEIS) for primary 10 keV He+ and 8 keV D+ ions to demonstrate an approach of providing accurate and precise experimental reference electronic stopping cross-sections for fusion-relevant steels. The energy-converted ToF-LEIS spectra are compared to Monte-Carlo simulations for quantitative analysis explicitly considering the influence of plural and multiple scattering. We discuss the deduced stopping cross-sections of EUROFER97 in comparison to predictions by SRIM using Bragg's rule of stopping power additivity.