Superconducting structure with layers of niobium nitride and aluminum nitride
US4844989A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1987 |
| Grant date | Jul 4, 1989 |
| Priority date | — |
| Expiry date | Mar 19, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N60/12
Abstract
A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.