All-niobium process for Josephson series array circuits

Author

Park, Se Il ; Kim, Kyu-Tae ; Lee, Rae Duk

Author_Institution

Electr. Group, Korea Res. Inst. of Standards & Sci., Taejon, South Korea

Volume

44

Issue

2

fYear

1995

fDate

4/1/1995 12:00:00 AM

Firstpage

241

Lastpage

244

Abstract

We have developed a new fabrication process for integrated Nb/Al ₂O₃/Nb Josephson series arrays using the selective niobium anodization process (SNAP), the image reversal technique (IRT) and lift-off. To avoid chaotic behavior, the critical current of the array was decreased by post-fabrication annealing or the in situ multilayer oxidation process. In the frequency range 70-100 GHz, the array containing 2520 junctions produced stable quantized voltage steps up to 2 V with step widths of 40-100 μA and stability times of more than 4 h

Keywords

aluminium compounds; annealing; anodisation; critical current density (superconductivity); integrated circuit technology; measurement standards; millimetre wave integrated circuits; niobium; oxidation; superconducting integrated circuits; superconducting junction devices; voltage measurement; 2 V; 40 to 100 muA; 70 to 100 GHz; Nb-Al₂O₃-Nb; Nb/Al₂O₃/Nb Josephson series arrays; critical current; fabrication; image reversal technique; in situ multilayer oxidation; lift-off; post-fabrication annealing; selective niobium anodization; stability times; Annealing; Chaos; Circuits; Critical current; Fabrication; Frequency; Niobium; Nonhomogeneous media; Oxidation; Voltage;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.377821

Filename

377821