Production of diamondlike carbon films through random compact cluster stacking

Carbon thin films exhibiting a different structure have been obtained using low-energy neutral-cluster beam deposition. The first-order Raman scattering of such materials exhibits some characteristic features related to the phonon density of states of diamond. A careful analysis shows that the electronic structure is not explained by a classical random network model such as Polk's model and an alternative film structure is proposed. In addition, the correlation between the free-cluster properties and the film properties seems to confirm the existence of the fullerenes in the 20--32-atom size range.