Manufacturing superconducting circuits out of ultrathin films is a
challenging task when it comes to patterning complex compounds, which are
likely to be deteriorated by the patterning process. With the purpose of
developing high-Tc superconducting photon detectors, we designed a novel
route to pattern ultrathin YBCO films down to the nanometric scale. We believe
that our method, based on a specific use of a focused-ion beam, consists in
locally implanting Ga^{3+} ions and/or defects instead of etching the film.
This protocol could be of interest to engineer high-Tc superconducting
devices (SQUIDS, SIS/SIN junctions and Josephson junctions), as well as to
treat other sensitive compounds.Comment: 13 pages, 7 figure