Electron emission from molybdenum under ion bombardment

Abstract

Reports measurements of electron emission yields of clean molybdenum surfaces under bombardment with H⁺, H₂⁺, D⁺, D₂⁺, He⁺, N⁺, N₂⁺, O⁺, O₂⁺, Ne⁺, Ar⁺, Kr⁺ and Xe⁺ in the wide energy range 0.7-60.2 keV. The clean surfaces were produced by inert gas sputtering under ultrahigh vacuum. The results were compared with those predicted by a core-level excitation model. The disagreement found when using correct values for the energy levels of Mo is traced to wrong assumptions in the model. A substantially improved agreement with experiment is obtained using a model in which electron emission results from the excitation of valence electrons from the target by the projectiles and fast recoiling target atoms.