Magnetoresistive playback head
US5748416A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 19, 1997 |
| Grant date | May 5, 1998 |
| Priority date | — |
| Expiry date | Mar 19, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3903
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An SAL-type magnetoresistive playback head that is highly sensitive and that limits Barkhausen noise is provided by optimizing the magnetic properties of the permanent magnet film. On top of a lower insulating layer are stacked a soft magnetic bias film (SAL film), a magnetic separating film (shunt film), a magnetoresistive film (MR film), and an upper insulating layer, in that order. The outer sides of the track of the MR film are in direct contact with the permanent magnet film or in indirect contact via a base film. Alternatively, the present invention relates to a spin-valve magnetoresistive playback head. On top of a lower insulating layer are stacked an anti-ferromagnetic film, a fixed magnetizing film, a magnetic separating film, a movable magnetizing film (MR film), and an upper insulating layer, in that order. The outer sides of the track of the movable magnetizing film are in direct contact with the permanent magnet film or in indirect contact via a base film. In either type of playback head, Barkhausen noise is eliminated by using a CoCrPt alloy film having a composition that provides the magnetic properties needed for a permanent magnet film that can handle narrow track…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.