Current-perpendicular-to-the-plane (CPP) magnetoresistive sensor with improved ferromagnetic free layer structure
US7551409B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2006 |
| Grant date | Jun 23, 2009 |
| Priority date | — |
| Expiry date | Jan 17, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/1278
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor has an improved free layer structure that includes a first ferromagnetic interface layer on the sensor's nonmagnetic spacer layer, a first electrically conductive interlayer on the first interface layer, a central ferromagnetic NiFe alloy free layer on the first interlayer, a second electrically conductive interlayer on the central free layer, and a second ferromagnetic interface layer on the second interlayer. The first ferromagnetic interface layer, central ferromagnetic free layer, and second ferromagnetic interface layer are ferromagnetically coupled together across the electrically conductive interlayers so their magnetization directions remain parallel. The free layer structure may be used in single or dual CPP sensors and in spin-valve or tunneling MR sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.