Interaction of multiply charged ions with tungsten solid surfaces: backscattered ions and secondary electrons

Results are concerned with backscattered ion and secondary electron emissions from impact, at normal incidence of Arq+ (1 ≤ q ≤ 9) ions on clean tungsten. For a given incident ion charge q, the reflection coefficient is roughly independent of the incident energy in the 10-120 keV range. This can be due to the balance between increase of the mean charge state of the backscattered particles when the energy increases and the decrease of the reflected ion number. Moreover, for a given incident energy, the mean charge of the backscattered particles increases with the charge of the incident ion. It was found a linear dependence of the total electron emission yield η versus q2. This result suggests that the field emission process could play a role in the secondary electron emission due to the interaction of multicharged ions with metallic surfaces