Title :
Self-shunted Nb/AlO/sub x//Nb Josephson junctions
Author :
Patel, V. ; Lukens, J.E.
Author_Institution :
Dept. of Phys., State Univ. of New York, Stony Brook, NY, USA
fDate :
6/1/1999 12:00:00 AM
Abstract :
We describe the fabrication and properties of high critical current density (J/sub c/) Nb/AlO/sub x//Nb Josephson junctions with deep-submicron dimensions. The junctions are fabricated using a planarized process in which all levels are patterned using a combination of optical and electron-beam lithography. The base and counter electrodes are defined by reactive ion etching using quartz etch masks to give a minimum feature size of 0.2 microns. For J/sub c/=2.1 mA//spl mu/m/sup 2/ and junction area less than 0.1 /spl mu/m/sup 2/ the devices are self-shunted and exhibit nonhysteretic I-V characteristics. A small hysteresis in the larger junctions is caused by heating in the electrodes.
Keywords :
Josephson effect; aluminium compounds; critical current density (superconductivity); niobium; 0.2 micron; I-V characteristics; Nb-AlO-Nb; critical current density; deep submicron technology; electron beam lithography; fabrication; hysteresis; optical lithography; planarization; reactive ion etching; self-shunted Nb/AlO/sub x//Nb Josephson junction; Counting circuits; Critical current density; Electrodes; Etching; Hysteresis; Josephson junctions; Lithography; Niobium; Optical device fabrication; Particle beam optics;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
