Singh, Manju and Chaujar, Rishu and Husale, Sudhir and Grover, S. and Shah, Amit P and Deshmukh, Mandar M. and Gupta, Anurag and Singh, V. N. and Ojha, V. N. and Aswal, D. K. and Rakshit, R. K. (2018) Influence of fabrication processes on transport properties of superconducting niobium nitride nanowires. Current Science, 114 (7). pp. 1443-1450. ISSN 0011-3891

PDF - Published Version Restricted to Registered users only Download (6Mb) | Request a copy

Abstract

Fabrication of niobium nitride (NbN) superconducting nanowires based on focused ion beam (FIB) milling and electron beam lithography (EBL) is presented. The NbN films were deposited using reactive magnetron sputtering. Argon-to-nitrogen ratio turned out to be a crucial factor in synthesizing high quality superconducting NbN. Critical temperatures (T-c) of around 15.5 K were measured for films with a thickness of around 10 nm. Zero-field-cooled magnetization was measured to optimize the superconducting properties of ultra thin NbN films. The transport behaviour was studied using conventional resistance vs temperature and current-voltage characteristics down to 2 K. Effect of gallium contamination on superconducting properties has been discussed. Whereas the various processing steps of standard EBL route do not have any significant impact on the superconducting transition temperature as well as on the transition width of nanowires, there is significant degradation of superconducting properties of nanowires prepared using FIB. This has been attributed to gallium ion implantation across the superconducting channel. Although the effect of gallium implantation may have technological limitations in designing fascinating single photon detector architectures, it provides some interesting low-dimensional superconducting properties.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s Indian Academy of Sciences.
Subjects:	Multidisciplinary Physics
Divisions:	UNSPECIFIED
Depositing User:	Users 27 not found.
Date Deposited:	18 Dec 2019 07:02
Last Modified:	18 Dec 2019 07:02
URI:	http://npl.csircentral.net/id/eprint/3778

Actions (login required)

View Item