Total electron emission yield for impact of slow Neq+(q = 2, 4, 6, 8) ions with various kinetic energy under normal incidence on n-type Si has been measured. It is shown that for the same charge state, the total electron yield γ increases linearly as the kinetic energy of projectile at impact increases, up to velocities corresponding to the “classical” threshold. Separation of kinetic electron yield γKE and potential electron yield γPE shows that γPE is proportional to the ion charge state and γKE increases linearly with projectile velocity. Finally, based on “single hole without hopping” hypothesis, the expression of the “CRF” F(q) is given, and the relation between γKE and q is obtained successfully for the first time, which is also a basis for judging whether the “trampoline effect” exists.
