Self-aligned contact process for Nb/Al-AlO/sub x//Nb Josephson junctions

Journal Article · Mon Jan 20 04:00:00 EST 1986 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.96573· OSTI ID:6306369

Morohashi, S; Hasuo, S; Yamaoka, T

High quality Nb/Al-AlO/sub x//Nb Josephson junctions have been fabricated by a novel process named the self-aligned contact process. After the definition of the junction area by a reactive ion etching (RIE) technique, the exposed Nb layer and the junction edge are anodized to protect against electrical shorts and an Al film is deposited as the etching stopper layer. After base electrode patterning by RIE, an insulation layer is deposited. The contact hole, with the diameter of the junction, for connecting a counter electrode and a wiring layer, can be made without registration because of the deposited Al film. The junctions fabricated by this process have exhibited excellent current-voltage characteristics (V/sub m/ = 70 mV at the critical current density j/sub J/ = 1.8 kA/cm/sup 2/, V/sub m/ = 11 mV at j/sub J/ = 20 kA/cm/sup 2/).

• Research Organization: Fujitsu Limited, 10-1 Morinosato-Wakamiya, Atsugi 243-01, Japan
• OSTI ID: 6306369
• Journal Information: Appl. Phys. Lett.; (United States), Journal Name: Appl. Phys. Lett.; (United States) Vol. 48:3; ISSN APPLA
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CRITICAL CURRENT
CURRENT DENSITY
CURRENTS
DATA
ELECTRIC CONDUCTIVITY
ELECTRIC CONTACTS
ELECTRIC CURRENTS
ELECTRICAL EQUIPMENT
ELECTRICAL FAULTS
ELECTRICAL PROPERTIES
ELECTRODES
ELEMENTS
EQUIPMENT
ETCHING
EXPERIMENTAL DATA
FABRICATION
INFORMATION
JOSEPHSON JUNCTIONS
JUNCTIONS
LAYERS
METALS
NIOBIUM
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SUPERCONDUCTING JUNCTIONS
SURFACE FINISHING
TRANSITION ELEMENTS