Introduction to 3D Printing Technique with Nanopipette-AFM for Fabrication of Quantum Dot-aggregated Nanowire

In this study, we would like to introduce a 3D printing technology on the nanoscale that utilizes nanophotonics and a modified atomic force microscope (AFM) for the assembly of quantum dots. Quantum dots are semiconductor nanostructures with zero-dimensional crystal structures at the nanometer scale, exhibiting unique optical properties due to quantum confinement effects. These quantum dots, with sizes on the order of a few nanometers, have garnered significant attention in various optical fields. By printing these quantum dots onto 2D materials or other substrates in desired shapes, we open up possibilities for controlling their energy structures and utilizing them in various ways. In this technology, we inject a quantum dot solution into the nanophotonic tip and use an AFM to precisely deposit the quantum dots at desired locations and shapes. In the initial stages of this technology, we achieve this by ejecting the quantum dot solution onto the surface through the holes in the nanophotonic tip. Simultaneously, as we retract the nanophotonic tip vertically, the liquid containing quantum dots evaporates, leading to the formation of bundled quantum dot nanowires. This innovative approach holds promise for a wide range of applications where precise manipulation of quantum dots at the nanoscale is crucial.