Abstract
Abstract
Superconducting circuits based on Josephson junctions have the potential to achieve high speed and ultra-low power consumption, but their integration is limited by the low controllability of Nb-based tunnel junction and the existence of shunt resistors. In this work, we report the fabrication of superconductor/normal metal/superconductor (SNS) Josephson junctions with high reproducibility on oxidized Si substrates. The junctions based on NbN/TaN/NbN trilayers measured at 4.2 K show excellent Josephson properties with a wide range of critical current (I
c) from 227 to 2000 μA. The variations of critical current density (J
c) and characteristic voltage (V
c) are respectively less than 7.1% and 7.5% in the 2 inch region. The standard deviation of I
c is calculated to be less than 1.7% for Josephson arrays with the number of junctions up to 10 000 occupying an area of 0.34 mm2. The results provide a guarantee for the applications of NbN-SNS Josephson junctions in superconducting large-scale integrated circuits.
Funder
Frontier Science Key Programs of CAS
National Natural Science Foundation of China
Young Investigator Program of the CAS
“Strategic Priority Research Program (A)” of the Chinese Academy of Sciences
Subject
Materials Chemistry,Electrical and Electronic Engineering,Metals and Alloys,Condensed Matter Physics,Ceramics and Composites