Sputtering of mixed materials of beryllium and tungsten by hydrogen and helium

The interaction of mixed Beryllium/Tungsten targets with Hydrogen and Helium is studied using the binary collision code SDTrim-SP. We restrict the study to a sub-set of material mixes expected to be stable Be, Be2W, Be12W, Be24W, and W. The dynamic changes of the surface and subsequent effects on sputter rates and other quantities are analyzed. In the mixed systems it is very important to use the dynamic mode, because the change of surface composition by the impact of the projectiles changes the sputter yield. Therefore, the sputter yield calculated from the dynamic mode can differ substantially from results assuming a static target not influenced by the impact of the projectiles.