Electron stimulated desorption of H~(+) ions physisorbed on rare gas solid and Cu surface

摘要

An electron stimulated desorption (ESD) experiment system fabricated to investigate ESD ions of hydrogen adsorbedon metal surfaces. Kr, Xe and H_(2) were adsorbed on a clean copper surface; the residual as well as desorbed hydrogen ions were investigated. Desorbed H~(+) and H_(2~(+)) ions of exposed H_(2) on the surface of rare-gas solid were much higher than H_(2) exposed directly to the surface of Cu. The desorption yields of H~(+) ion was much larger from the solid Xe than from the solid Kr. The kinetic energy of desorbed H~(+) and H_(2~(+)) ions depends on incident electron energy. When the electron incident energy was 200 eV, the kinetic energies of H~(+) and H_(2~(+)) were 5.0044 eV and 0.8405 eV respectively. Also desorption yields of H~(+) ions were systematically measured as function of H_(2) pressure upon the cold surface.