Magnetoresistive sensor with recessed antiferromagnetic layer and stabilization feature
US10008223B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 2017 |
| Grant date | Jun 26, 2018 |
| Priority date | — |
| Expiry date | Feb 17, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/3996
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A read sensor having a bearing surface and an antiferromagnetic (AFM) layer recessed from the bearing surface. The read sensor includes a synthetic antiferromagnetic (SAF) structure over the AFM layer. The SAF structure includes a recessed lower pinned layer, an upper pinned layer, a reference layer and a stabilization feature. The stabilization feature may include deliberate reduction of the antiferromagnetic coupling energy density between the upper pinned layer and the reference layer, so that it becomes lower than the first energy density of antiferromagnetic coupling between the upper pinned layer and the lower pinned layer. The stabilization feature may alternatively include an intermediate pinned layer between the lower pinned layer and the upper pinned layer. The intermediate pinned layer is antiferromagnetically coupled to both the lower pinned layer and the upper pinned layer, and at least a portion of the intermediate pinned layer is recessed behind the bearing surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.