Determination of ion fraction and energy analysis of sputtered particles from deuterium bombarded surfaces

Ion energy distributions and sputtering yields have been measured in the presence of various background gases for deuterium, helium and argon ions in the 1–40 keV energy range. Alteration of the surface chemistry of hydride forming metals such as Ti, Y and V by exposure to hydrogen has a significant effect on the charge state of the sputtered particles. Under conditions likely to prevail in plasma devices and possible reactors, the ion/neutral fraction may be drastically increased, reaching ~41% for Ti. Such large ion fractions for metal targets have been previously observed only by sputtering with oxygen ions and present the possibility of improved impurity control in plasma devices. Both gas adsorption and recoil implantation are involved in the mechanism determining the ion fraction of sputtered products.