Development of NbN Josephson Junction Technology.

Abstract

A novel process suitable for fabrication superconducting circuitry based on the all refactory material NbN is described. In this process, and in-situ trilayer film composed of NbN/MgO/NbN is used to fabricate Josephson tunnel junctions. Reactive ion etching processes are used to delineate devices and pattern insulators and metallizations. Fabricated junctions have yielded good tunneling characteristics with reasonable current density uniformity and reproducibility. Devices with gap voltages close to 3mV have been achieved for high quality junctions (Vm > 20 mV). In addition to the trilayer, there are two wiring layers, two resistor depositions, and two insulation layers, constituting a full NbN based fabrication technology. Using this process, we fabricated and successfully tested thin film DC SQUID and time domain reflectometer (TDR) circuits. Preliminary measurements suggest that the critical temperature of these circuits is well within the operating temperature of commercial two-stage closed cycle refrigerators. (Author)

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jul 24, 1986
Accession Number
ADA171067

Entities

People

  • M. Radparvar

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Circuits
  • Critical Temperature
  • Current Density
  • Dry Etching
  • Etching
  • Fabrication
  • Films
  • Generators
  • Integrated Circuits
  • Josephson Junctions
  • Magnetometers
  • Materials
  • Measurement
  • Reactive Ion Etching
  • Thin Films
  • Time Domain Reflectometer
  • Transition Temperature

Fields of Study

  • Physics

Readers

  • Integrated Circuit Design and Technology.
  • Superconducting Magnet Technology
  • Thin Film Deposition Science.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene