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

Volume

9

Issue

2

fYear

1999

fDate

6/1/1999 12:00:00 AM

Firstpage

3247

Lastpage

3250

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;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.783721

Filename

783721