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Title: Epitaxial NbN/AlN/NbN tunnel junctions on Si substrates with TiN buffer layers

Abstract

We have developed epitaxial NbN/AlN/NbN tunnel junctions on Si (100) substrates with a TiN buffer layer. A 50-nm-thick (200)-oriented TiN thin film was introduced as the buffer layer for epitaxial growth of NbN/AlN/NbN trilayers on Si substrates. The fabricated NbN/AlN/NbN junctions demonstrated excellent tunneling properties with a high gap voltage of 5.5 mV, a large I{sub c}R{sub N} product of 3.8 mV, a sharp quasiparticle current rise with a ΔV{sub g} of 0.4 mV, and a small subgap leakage current. The junction quality factor R{sub sg}/R{sub N} was about 23 for the junction with a J{sub c} of 47 A/cm{sup 2} and was about 6 for the junction with a J{sub c} of 3.0 kA/cm{sup 2}. X-ray diffraction and transmission electron microscopy observations showed that the NbN/AlN/NbN trilayers were grown epitaxially on the (200)-orientated TiN buffer layer and had a highly crystalline structure with the (200) orientation.

Authors:
 [1];  [2]; ;  [3];  [1];  [1];  [2];  [2]
  1. State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China)
  2. (China)
  3. Advanced ICT Research Institute, National Institute of Information and Communications Technology (Japan)
Publication Date:
OSTI Identifier:
22611539
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM NITRIDES; BUFFERS; CRITICAL CURRENT; CURRENT DENSITY; ELECTRIC CONTACTS; EPITAXY; LAYERS; LEAKAGE CURRENT; NIOBIUM NITRIDES; QUALITY FACTOR; SEMICONDUCTOR JUNCTIONS; SUBSTRATES; SUPERCONDUCTING JUNCTIONS; THIN FILMS; TITANIUM; TITANIUM NITRIDES; TRANSMISSION; TRANSMISSION ELECTRON MICROSCOPY; TUNNEL EFFECT; X-RAY DIFFRACTION

Citation Formats

Sun, Rui, University of Chinese Academy of Sciences, Beijing 100049, Makise, Kazumasa, Terai, Hirotaka, Zhang, Lu, Wang, Zhen, E-mail: zwang@mail.sim.ac.cn, University of Chinese Academy of Sciences, Beijing 100049, and Shanghai Tech University, Shanghai 201210. Epitaxial NbN/AlN/NbN tunnel junctions on Si substrates with TiN buffer layers. United States: N. p., 2016. Web. doi:10.1063/1.4954743.
Sun, Rui, University of Chinese Academy of Sciences, Beijing 100049, Makise, Kazumasa, Terai, Hirotaka, Zhang, Lu, Wang, Zhen, E-mail: zwang@mail.sim.ac.cn, University of Chinese Academy of Sciences, Beijing 100049, & Shanghai Tech University, Shanghai 201210. Epitaxial NbN/AlN/NbN tunnel junctions on Si substrates with TiN buffer layers. United States. doi:10.1063/1.4954743.
Sun, Rui, University of Chinese Academy of Sciences, Beijing 100049, Makise, Kazumasa, Terai, Hirotaka, Zhang, Lu, Wang, Zhen, E-mail: zwang@mail.sim.ac.cn, University of Chinese Academy of Sciences, Beijing 100049, and Shanghai Tech University, Shanghai 201210. 2016. "Epitaxial NbN/AlN/NbN tunnel junctions on Si substrates with TiN buffer layers". United States. doi:10.1063/1.4954743.
@article{osti_22611539,
title = {Epitaxial NbN/AlN/NbN tunnel junctions on Si substrates with TiN buffer layers},
author = {Sun, Rui and University of Chinese Academy of Sciences, Beijing 100049 and Makise, Kazumasa and Terai, Hirotaka and Zhang, Lu and Wang, Zhen, E-mail: zwang@mail.sim.ac.cn and University of Chinese Academy of Sciences, Beijing 100049 and Shanghai Tech University, Shanghai 201210},
abstractNote = {We have developed epitaxial NbN/AlN/NbN tunnel junctions on Si (100) substrates with a TiN buffer layer. A 50-nm-thick (200)-oriented TiN thin film was introduced as the buffer layer for epitaxial growth of NbN/AlN/NbN trilayers on Si substrates. The fabricated NbN/AlN/NbN junctions demonstrated excellent tunneling properties with a high gap voltage of 5.5 mV, a large I{sub c}R{sub N} product of 3.8 mV, a sharp quasiparticle current rise with a ΔV{sub g} of 0.4 mV, and a small subgap leakage current. The junction quality factor R{sub sg}/R{sub N} was about 23 for the junction with a J{sub c} of 47 A/cm{sup 2} and was about 6 for the junction with a J{sub c} of 3.0 kA/cm{sup 2}. X-ray diffraction and transmission electron microscopy observations showed that the NbN/AlN/NbN trilayers were grown epitaxially on the (200)-orientated TiN buffer layer and had a highly crystalline structure with the (200) orientation.},
doi = {10.1063/1.4954743},
journal = {AIP Advances},
number = 6,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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