Fabrication of low dimensional nanowire-based devices using dieletrophoresis

Bottom-up assembly of nanostructured materials, such as metallic nanowires and carbon nanotubes, has proven to be a facile way of building electronic devices or sensing platforms with unparallel ease of device dimension control. Electric field assisted manipulation of roughly 320nm diameter 6 μm long nanowires with composition of Au-Ag-Au under ac bias across the lithographically defined parallel electrodes forms the basis of bottom-up assembly approach followed in this study. Nanowires were first aligned electrofluidically under ac bias of 10 V _pp and 1 kHz across 5 and 6 μm separated electrodes. Chemical etching of the Ag segment in the nanowires aligned across the predefined electrodes resulted in reduction of the dimension of the electrode separation from 5 μm to 50-100 nm. The alignment yield of 6 μm Au-Ag-Au striped nanowires across gold electrodes was as high as 70%. The nanowires-based device was employed to the capture and electrical characterization of preferably a single 100nm Au nanosphere in the nanogap.