Magnetoresistive sensor having an anisotropic hard bias with high coercivity
US7848065B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2006 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Oct 6, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3932
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetoresistive sensor having magnetically anisotropic bias layers for biasing the free layer of the sensor. Hard bias structures for biasing the magnetization of the free layer are formed at either side of the sensor stack, and each of the hard bias structure includes a hard magnetic layer that has a magnetic anisotropy to enhance the stability of the biasing. The hard bias structure can include a Cr under-layer having a surface that has been treated by a low power angled ion milling to form it with an anisotropic surface texture. A layer of Cr—Mo alloy is formed over the Cr under-layer and the hard magnetic material layer is formed over the Cr—Mo alloy layer. The anisotropic surface texture of the Cr layer induces an aligned crystalline structure in the hard magnetic layer that causes the hard magnetic layer to have a magnetic anisotropy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.