Improved characteristics of Nb3Ge tunnel junctions using sputter-deposited amorphous-silicon barrier
Creators
- 1. Research Institute of Applied Electricity, Hokkaido University, Sapporo, Japan
Description
We have fabricated Nb3Ge/amorphous-silicon/Pb Josephson tunnel junctions using high T/sub c/(> or =20 K) and stoichiometric (25 +- 1 at. %Ge) Nb3Ge films. Good I-V characteristic with large Josephson current I/sub c/ and high gap voltage is obtained when the amorphous-silicon barrier is sputter deposited at low rf voltage and high Ar pressure to reduce the damage to the Nb3Ge by the sputtered particles and to obtain good coverage over the Nb3Ge surface. Peculiar I-V characteristics showing the inverse ac Josephson effect and chaotic transition betwen current steps are observed in the response to microwave. The temperature dependence of I/sub c/ agrees well with the theoretical calculation when the Ge enrichment at the top surface of the Nb3Ge electrode is reduced
Additional details
Publishing Information
- Journal Title
- J. Appl. Phys.
- Journal Volume
- 56
- Journal Issue
- 4
- Series
- J. Appl. Phys.
- Journal Page Range
- 1039-1043
- ISSN
- 0021-8979
INIS
- Country of Publication
- United States
- Country of Input or Organization
- United States
- INIS RN
- 16011206
- Subject category
- S46: INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY;
- Descriptors DEI
- AMORPHOUS STATE; ARGON; BINARY ALLOY SYSTEMS; CURIE POINT; ELECTRIC CONDUCTIVITY; FABRICATION; GERMANIUM ALLOYS; INTERMETALLIC COMPOUNDS; JOSEPHSON EFFECT; JOSEPHSON JUNCTIONS; LEAD; NIOBIUM BASE ALLOYS; SILICON; SPUTTERING; TEMPERATURE DEPENDENCE; TRANSITION TEMPERATURE; TUNNEL EFFECT
- Descriptors DEC
- ALLOY SYSTEMS; ALLOYS; ELECTRICAL PROPERTIES; ELEMENTS; METALS; NIOBIUM ALLOYS; NONMETALS; PHYSICAL PROPERTIES; RARE GASES; SEMICONDUCTOR JUNCTIONS; SEMIMETALS; THERMODYNAMIC PROPERTIES