Intrinsically shunted NbN/TaN/NbN Josephson junctions on Si substrates for large-scale integrated circuits applications. (1st June 2022)

• Record Type: Journal Article
• Authors: Yan, Kaixin; Zhang, Lu; Zhong, Yulong; Shi, Jiasheng; Shi, Weifeng; Wu, Ling; Wang, Huiwu; Chen, Lei; Ren, Jie; Peng, Wei; Wang, Zhen
• Is Part Of: Superconductor science & technology. Volume 35:Number 6(2022)
• Publication Date: 2022-06-01
• Subjects: NbN/TaN/NbN -- SNS Josephson junctions -- high uniformity and reproducibility; Superconductivity -- Periodicals; Superconductors -- Periodicals; 537.623
• DOI: 10.1088/1361-6668/ac591d
• Languages: English
• ISSNs: 0953-2048

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 μ A. 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 mm 2 . The results provide a guarantee for the applications of NbN-SNS Josephson junctions in superconducting large-scale integrated circuits.