Directed Assembly of Au-Tipped 1D Inorganic Nanostructures via Nanolithographic Docking

Controlled assembly of nanostructures is a key challenge in nanotechnology. In this work, we introduce an approach for the controlled assembly of 1D nanodumbbells-Au-tipped semiconductor nanorods-into arbitrary 2D higher architectures, by their chemical docking to nanopatterned functionalities. We realized the docking functionalities via nanoimprinted metallic nanodots functionalized with an organic monolayer, whose terminal thiol groups chemically bind the nanodumbbell tips. We demonstrated that the functional nanopattern encodes the nanodumbbell assembly and can be designed to deterministically position nanodumbbells in two possible modes. In the single-docking mode, the nanodot arrays are designed with a spacing that exceeds the nanodumbbell length, restricting each nanodumbbell to dock with one edge and physically connect with its free edge to one of the neighboring nanodumbbells. Alternatively, in the double-docking mode, the nanodots are spaced to exactly fit the nanodumbbell length, allowing nanodumbbell docking with both edges. We found that the docking kinetics can be described by a random attachment model, and verified that for the used docking chemistry, nanodumbbells that are docked to the same dot do not interact with each other. Our work demonstrates the possibility for massively parallel positioning of sub-100 nm 1D semiconductor nanostructures, and can potentially enable their future integration into functional nanodevices and nanosystems.