GMR device having an improved free layer
US7477491B2 · kind B2 · utility
30Cited by
7References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2005 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Nov 18, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49044
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
It has been found that the insertion of a copper laminate within CoFe, or a CoFe/NiFe composite, leads to higher values of CPP GMR and DRA. However, this type of structure exhibits very negative magnetostriction, in the range of high −10−6 to −10−5. This problem has been overcome by giving the copper laminates an oxygen exposure treatment When this is done, the free layer is found to have a very low positive magnetostriction constant. Additionally, the value of the magnetostriction constant can be adjusted by varying the thickness of the free layer and/or the position and number of the oxygen treated copper laminates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.