Single-electron devices formed by self-ordering metal nanodroplet arrays on epitaxial CaF2 film

Single-electron devices using a self-ordering metal nanodroplet array as mu ltitunneling junctions (MTJ) were fabricated. The nanodroplet array was fab ricated by sequential deposition of Al and Ga on a epitaxial CaF2 him grown on Si substrate, so that the Ga/Al droplets were aligned along the CaF2 st ep edges. Current-voltage characteristics of an MTJ diode and an MTJ transi stor showed a Coulomb staircase at 55 K and 287 K, respectively. A large Co ulomb gap observed on a source-drain current indicates that electrons tunne l a large number of nanodroplet arrays.