A nanocapacitor with giant dielectric permittivity

A nanocapacitor with ultra high capacitance (718 ± 0.2 pF) has been fabricated using electro-deposited Au nanowires manipulated between two Au microelectrodes by the dielectrophoresis technique. A high dc resistance value (∼100 M ) and nonlinear current–voltage characteristics indicate the formation of a dielectric interface between the nanowires. From frequency dependent conductivity, it is seen that the interface exhibits a giant dielectric permittivity (ε ∼ 1.8 × 107), which shows no frequency dispersion over the range from 30 Hz to 1 MHz. The enhancement of this permittivity value is attributed to the formation of a disordered interface containing gold atoms disrupted from the surface of the Au nanowires.