Title :
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
fDate :
4/1/1995 12:00:00 AM
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;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
