MONTE-CARLO SIMULATION OF KINETIC ELECTRON-EMISSION FROM A METAL-SURFACE UNDER KEV HEAVY-ION BOMBARDMENT

A Monte Carlo model is developed for charge-state-dependent kinetic emission (KE) of electrons from Au bombarded by keV Ar(q+) (q = 0, 1, 2). At low impact energy, the calculated electron yield is smaller than the observed yield due to the absence of potential emission (PE), whereas with increasing impact energy, the calculated and observed yields for Ar+ impact approach each other due to dominant KE. For KE, there is a wide spread in the number of emitted electrons, although PE ejects one (one or two) electron for Ar+ (Ar2+). The energy distribution of electrons ejected by KE has a peak at 2-3 eV, the position of which is independent of the energy and charge state of the projectile.