A novel method to fabricate large-area superconducting hybrid tunnel junctions with a suspended central normal metal part is presented. The samples are fabricated by combining photo-lithography and chemical etch of a superconductor - insulator - normal metal multilayer. The process involves few fabrication steps, is reliable and produces extremely high-quality tunnel junctions. Under an appropriate voltage bias, a significant electronic cooling is demonstrated.
@article{arxiv.1111.3541,
title = {Etching suspended superconducting hybrid junctions from a multilayer},
author = {Hung Q. Nguyen and Laetitia Pascal and Z. H. Peng and Olivier Buisson and B. Gilles and Clemens Winkelmann and Hervé Courtois},
journal= {arXiv preprint arXiv:1111.3541},
year = {2022}
}