COLLISION OF HYPERTHERMAL ATOMS WITH AN ADSORBATE COVERED SOLID-SURFACE .2. COLLISION-INDUCED DESORPTION

In the present study, a molecular dynamics approach was used to simulate the collision-induced desorption process. In particular, the scattering of a hyperthermal atom from an adsorbate-covered (monolayer) solid surface was examined. The desorption may be induced by the direct interaction between the projectile and the adsorbed particles as well as by an indirect through-surface interaction. The indirect process is related to the formation of a "hot spot" which results from energy transfer to the solid surface during the scattering event. It was found that the probability of the indirect process was much smaller than that of the direct process, and that the indirect desorption yield was due to a collision cascade type mechanism.