title: The effect of plasma impurities on the sputtering of tungsten carbide.
abstract: Understanding of sputtering by ion bombardment is needed in a wide range of applications. In fusion reactors, ion impacts originating from a hydrogen-isotope-rich plasma will lead, among other effects, to sputtering of the wall material. To study the effect of plasma impurities on the sputtering of the wall mixed material tungsten carbide molecular dynamics simulations were carried out. Simulations of cumulative D cobombardment with C, W, He, Ne or Ar impurities on crystalline tungsten carbide were performed in the energy range 100-300 eV. The sputtering yields obtained at low fluences were compared to steady state SDTrimSP yields. During bombardment single C atom sputtering was preferentially observed. We also detected significant W(x)C(y) molecule sputtering. We found that this molecule sputtering mechanism is of physical origin.
authors.affiliation: Association EURATOM-Tekes, Department of Physics, University of Helsinki, PO Box 43, FIN-00014, Finland. katharina.vortler@helsinki.fi
authors.forename: K
authors.initials: K
authors.lastname: Vörtler
authors.forename: C
authors.initials: C
authors.lastname: Björkas
authors.forename: K
authors.initials: K
authors.lastname: Nordlund