Effect of wire length on Coulomb blockade in ultrathin wires of recrystallized hydrogenated amorphous silicon

Electron transport in nanowires of hydrogenated amorphous silicon recrystallized by electron beam annealing has been studied. Wire length dependent electrical characteristics have been measured at low temperatures. Evidence for single electron effects with I–V characteristics has been presented. Transmission electron microscopy and photoluminescence data are used to support the electrical results. The Coulomb blockade effect is modeled as a combination of hopping conduction between a limited number of trapping sites in amorphous regions or at grain boundaries with additional Coulomb blockade effects as well as a confinement due to potential fluctuations arising from dopant distribution.