Title :
Fabrication of YBaCuO junctions by the irradiation of focused ion beam
Author :
Shiga, H. ; Soutome, Y. ; Okabe, Y.
Author_Institution :
Res. Center for Adv. Sci. & Technol., Tokyo Univ., Japan
fDate :
6/1/1999 12:00:00 AM
Abstract :
We have fabricated Josephson junctions in YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBaCuO) thin films by the irradiation of focused ion beam (FIB). We used Be/sup 2+/ ions with the energy of 200 keV. When the fluence of Be/sup 2+/ ions was 1.2/spl times/10/sup 16/ ions/cm/sup 2/, the I-V characteristics of the junctions at 4.2 K showed RSJ-like characteristics with the excess current. The I/sub c/R/sub n/ product of the junctions was 1.1 mV at 6.3 K. Shapiro steps up to 20th step could be observed by the irradiation of 8.47 GHz microwave at 6.3 K. The magnetic modulation curve of the junction at 4.2 K was similar to the Fraunhofer pattern. These characteristics remained unaltered after preservation in a desiccator for 6 months.
Keywords :
Josephson effect; barium compounds; focused ion beam technology; high-temperature superconductors; superconducting thin films; yttrium compounds; 200 keV; 4.2 to 6.3 K; 8.47 GHz; Fraunhofer pattern; I-V characteristics; Josephson junction; RSJ model; Shapiro step; YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin film; YBa/sub 2/Cu/sub 3/O/sub 7/; focused ion beam irradiation; magnetic modulation; microwave irradiation; Fabrication; Gold; Ion beams; Josephson junctions; Lithography; Pulsed laser deposition; Substrates; Superconducting films; Transistors; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
