Fabrication of Low Dimensional Nanowire-Based Devices using Dieletrophoresis

Abstract

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 320 nm diameter $6\,\mu \mathrm{m}$ 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 $6\,\mu \mathrm{m}$ 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 $5\,\mu \mathrm{m}$ to 50–100 nm. The alignment yield of $6\,\mu \mathrm{m}$ 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 100 nm Au nanosphere in the nanogap.