Magnetoresistive device of the CPP type, and magnetic disk system
US7961438B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 2008 |
| Grant date | Jun 14, 2011 |
| Priority date | — |
| Expiry date | Nov 14, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/3996
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention provides a magnetoresistive device of the CPP (current perpendicular to plane) structure, comprising a magnetoresistive unit, and a first shield layer and a second shield layer which are located and formed such that the magnetoresistive unit is sandwiched between them with a sense current applied in a stacking direction. The magnetoresistive unit comprises a nonmagnetic intermediate layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked and formed such that the nonmagnetic intermediate layer is sandwiched between them. The first shield layer and the second shield layer are each controlled by magnetization direction control means in terms of magnetization direction to create an antiparallel magnetization state where their magnetizations are in opposite directions. The first ferromagnetic layer and the second ferromagnetic layer are exchange coupled to the first shield layer and the second shield layer, respectively, by way of a first exchange coupling function gap layer and a second exchange coupling function gap layer, with an exchange coupled strength of 0.2 to 2.5 erg/cm2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.