Manufacturing of Sub-20 NM Wide Single Nanowire Devices using Conventional Stepper Lithography

Single nanowires have a broad range of applications in chemical and bio-sensing, photonics, and material science, but realizing individual nanowire devices in a scalable manner remains extremely challenging. This work presents a scalable and flexible method to realize single gold nanowire devices. We use conventional optical stepper lithography to generate notched beam structures, and crack lithography to obtain sub-20-nm-wide nanogaps at the notches, thereby obtaining a suitable shadow mask to define a single nanowire device. Then a gold evaporation step through the shadow mask forms the individual gold nanowires with positional and dimensional accuracy and with electrical contacts to probing pads.