We report on the fabrication of superconducting nanowire arrays through photothermal effects induced by nano laser direct writing (NLDW), with progressively reduced spacing between the laser paths. The superconducting nanowire arrays were fabricated on 50 nm-thick Nb films via sputtering deposition on high-resistivity silicon substrates. Large-scale fabrication of superconducting nanowire arrays using NLDW has advantages such as cost-effectiveness, efficiency, and design flexibility. Furthermore, the thermal effects induced the degradation of Nb films with narrowing spacing, which were analyzed using simulated temperature distribution, electron probe X-ray micro-analysis, and electrical transport measurements. Specifically, the critical point of spacing (6.7 pixels) was confirmed, at which the Nb nanowires exhibited resistive behavior at 4.0 K. Similar to the pattern overlap and multiple exposure techniques in semiconductor fabrication, by designing appropriate spacing, the width of the remaining functional Nb film could be reduced to several tens of nanometers or even down to a few nanometers. Compared with traditional micro–nano fabrication techniques such as electron beam lithography and focused ion beams, the NLDW technique provides a reliable, economical, and reproducible pathway for scaling up superconducting circuits, as well as an avenue to conduct nanoscale thermal engineering on superconducting materials for basic scientific studies.

To realize large-scale micro/nanofabrication process in superconducting devices, the nano laser direct writing (NLDW) as a potential tool was implemented. In this paper, thermal effect induced laser-matter (superconducting film) interaction based on laser direct writing on Nb films and laser exposure on photoresist were investigated by simulation and experiment. To avoid nanoscale thermal effect on superconducting films, large-scale superconducting nanoarrays with the area up to 100 μm × 100 μm based on laser exposure on photoresist were fabricated. Compared with laser direct writing on superconducting films, which lead to the degradation of superconducting performance such as critical current, transition temperature, the superconducting nanoarrays based on laser exposure on photoresist maintain excellent superconducting performance without degradation. Besides that, by further optimizing the process parameters and the thickness of photoresist, the nanowires with the width down to nanometers are plausible. Compared with the traditional electron beam and ion beam process, to some extent, the nanowires fabrication process based on NLDW provides a more efficient and cost-effective path for the fabrication of large-area superconducting devices/circuits.