What is gas cluster ion beam?

●Gas cluster ion beam(GCIB) is a novel ion beam, which was found by I. Yamada(professor emeritus, Kyoto Univ.).
The gas cluster, which consists of several thousands of atoms, is ionized and bombarded on a substrate. In the case of prior single ion beam, a single atom is ionized and irradiated on a substrate. The cluster ion bombardment has superior characteristic effects, that is not obtained by the irradiation of single ion beams.