A Nanoscale-Localized Ion Damage Josephson Junction Using Focused Ion Beam and Ion Implanter

作者：Wu C H^*; Kuo W S; Jhan F J; Chen J H; Jeng J T

来源：Journal of Nanoscience and Nanotechnology, 2015, 15(5): 3728-3732.

DOI：10.1166/jnn.2015.9757

• Josephson Junction
• Ion Implantation
• Ion Damage

High-T-c Josephson junctions were fabricated by nanolithography using focused ion beam (FIB) milling and ion implantation. The junctions were formed in a YBa2Cu3O7-x thin film in regions defined using a gold-film mask with 50-nm-wide (top) slits, engraved by FIB. The focused ion beam system parameters for dwell time and passes were set to remove gold up to a precise depth. 150 keV oxygen ions were implanted at a nominal dose of up to 5 x 10(13) ions/cm(2) into YBa2Cu3O7-x microbridges through the nanoscale slits. The current-voltage curves of the ion implantation junctions exhibit resistive-shunted-junction-like behavior at 77 K. The junction had an approximately linear temperature dependence of critical current. Shapiro steps were observed under microwave irradiation. A 50-nm-wide slit and 0-20-nm-thick buffer layers were chosen in order to make Josephson junctions due to the V-shape of the FIB-milled trench.

• 出版日期2015-5