Superconducting Nanowire Fabrication using Dislocation Engineering

Fabrication of superconducting devices can be a long and difficult process, especially at the nanoscale. During post-fabrication, another issue arises since the superconducting material is prone to degradation over time. Currently, traditional methods of fabrication, such as electron-beam lithography, are being used to develop these devices. In this study, we explored the usage of a process called dislocation engineering that modifies the lattice structure of the superconductor to change its intrinsic properties. To achieve this, the ion beam from a scanning helium ion microscope was used to damage the material. Dose response tests were performed to determine helium ion beam parameters to modify the superconductive lattice sufficiently. For the test, a nanowire was damaged for each trial of different doses, and the current-voltage characteristics were determined for the resulting structure. Results showed that using the helium ion beam for dislocation engineering to fabricate nanowire has promise. One application of such fabricated devices could be for superconducting nanowire single-photon detectors (SNSPDs).