Masked ion beam irradiation of high-temperature superconductors: patterning of nano-size regions with high point-defect density

Author(s): Wolfgang Lang, Herbert Richter, Markus Marksteiner, Khurram Siraj, Marius Bodea, Johannes D. Pedarnig, Costas Grigoropoulos, Dieter Bäuerle, Christine Hasenfuss, Leopold Palmetshofer, R. Kolarova, Peter Bauer
Abstract: Ion-beam irradiation of high-temperature superconductors creates different types of defects depending on ion mass, energy and dose. Computer simulations reveal the diversity of the ion-target interactions with YBa₂Cu₃O₇ and are compared to previous experimental results from transmission electron microscopy and electrical transport properties. While protons have a very low efficiency to create defects in YBa₂Cu₃O₇, significantly heavier ions produce defect clusters and inhomogeneous damage in the target material. The situation is exemplarily illustrated by a computer simulation study of the defect cascades produced by H⁺, He⁺, Ne⁺, and Pb⁺ ions of moderate energy. He⁺ ions with energy of about 75 keV were found useful for a systematic modification of the electrical properties of high-temperature superconductors, since they do not implant into 100-nm thick films of YBa₂Cu₃O₇ but primarily create point defects by displacement of the oxygen atoms. Such defects are very small and distributed homogeneously in YBa₂Cu₃O₇. The small lateral spread of the collision cascades allows for the patterning of nanostructures by directing a low-divergence beam of He+ ions onto a thin film of YBa₂Cu₃O₇ through a mask. Simulations indicate that the resolution can be about 10 nm. An experimental test with a masked ion beam irradiation confirmed that features with about 200 nm size could be produced in a YBa₂Cu₃O₇ thin film and observed by scanning electron microscopy.
Organisation(s): Electronic Properties of Materials, Quantum Optics, Quantum Nanophysics and Quantum Information
External organisation(s): Johannes Kepler Universität Linz, University of California, Berkeley
Journal: International Journal of Nanotechnology
Volume: 6
Pages: 704-714
No. of pages: 11
ISSN: 1475-7435
DOI: https://doi.org/10.1504/IJNT.2009.025308
Publication date: 2009
Peer reviewed: Yes
Austrian Fields of Science 2012: 1030 Physics, Astronomy
Portal url: https://ucris.univie.ac.at/portal/en/publications/masked-ion-beam-irradiation-of-hightemperature-superconductors-patterning-of-nanosize-regions-with-high-pointdefect-density(36da1718-2533-4699-bd52-3d92ab135c46).html