Magnetoresistive read transducer assembly
US4825325A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 30, 1987 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Oct 30, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3903
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetoresistive (MR) sensor which is provided with longitudinal bias by means of exchange coupling between the ferromagnetic MR layer (NiFe) and an ultrathin layer of an antiferromagnetic material (FeMn) with a thickness within the range of about 25 to 200 angstroms. The exchange structure is capped by a protective film to prevent oxidation damage to the exchange structure during subsequent thermal cycling. The capping layer is a dielectric or metal oxide (cermet) film such as Cr.sub.2 O.sub.3, Al.sub.2 O.sub.3, Cr - SiO or Si O.sub.2. Alternatively, the capping layer can be a laminated FeMn-Lx film where Lx is taken from the group consisting of Cr.sub.2 O.sub.3, Al.sub.2 O.sub.3, and Si O.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.