On the phenomenon of direct emission of small Si +n( n = 2, 3) clusters from an Ar +-bombarded Si surface

Abstract

Very few works till now support the direct emission phenomenon for small clusters (ions or neutrals) from an ion-bombarded surface, and moreover, all such works present only evidences but do not actually probe into the possible processes behind such emission. Our previous work on this line evaluates the experimental conditions under which the direct emission mechanism predominates over recombination phenomena. The experimental results also suggest that the concerned cluster ions are emitted “as such” (directly) from the ion-bombarded surface. The present work is actually a follow-up of the previous work, and strengthens the above concept from a different angle. Moreover, in the light of some very recent concepts, the possible processes leading to such emission are suggested. The phenomenon highlights the importance of evaporation effects from the impact zone at increased target current densities ( J P) .