In-situ nanorobotic soldering of three-dimensional helical nanobelts using gold nanoink

In this paper, we report an in-situ nanosoldering technique to make electrically conductive interconnections between three-dimensional (3D) helical micro-/nanostructures and electrodes for the nanorobotic assembly of nanoelectromechanical systems (NEMS) using gold nanoparticle ink. 3D helical nanobelts are placed onto pre-fabricated gold electrodes using nanorobotic manipulation inside a scanning electron microscope (SEM), and then deposited with gold nanoparticle ink using fountain-pen method to improve the electrical conductivity. Electrical and mechanical characterization shows the stable reduction of contact resistance and strength of the assembled structures, which is important to build 3D NEMS devices based on nanorobotic assembly.