TUNNELING IN MULTILAYER FULLERENE AL2O3 AND FULLERENE/GE SYSTEMS/

We discuss results on tunneling in barriers consisting of both pure fu llerene films and layered composites of fullerenes and dielectric mate rials. This work focuses on C-60 films, which ranged from 50 to 600 An gstrom in thickness and were layered with both Al2O3 and Ge films 10 t o 40 Angstrom in thickness. These studies reveal that for the depositi on conditions used here, incomplete C-60 coverage occurred for film th icknesses less than similar to 400 Angstrom. For composites of C-60 wi th Al2O3 or Ge, we observed isolated clusters of C-60 molecules and Co ulomb blockade behavior consistent with the size scale of the clusters . Interesting dynamical effects were also observed in conductance char acteristics that were both dramatic and in some cases entirely reprodu cible. [S0163-1829(98)02440-0].