Process for producing niobium Josephson junctions
US4458409A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1983 |
| Grant date | Jul 10, 1984 |
| Priority date | — |
| Expiry date | Jan 20, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49014
Abstract
A process for reducing the particle current in the sub-gap range of all-Nb Josephson junctions. The process results in junctions having substantially increased values of V.sub.m. In order to reduce the single particle current, the reaction between the barrier layer oxide and the counter electrode is prevented by additional process steps. After forming the tunnel barrier (4) and before depositing the counter electrode (9), the tunnel barrier surface is covered with a thin, non-continuous layer (5) of a material such as gold which is not reacting with oxygen at process conditions. Subsequently, the non-covered barrier layer surface regions (7) are strongly oxidized thereby forming an oxide layer (8) of sufficient thickness to prevent electron tunneling in these regions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.