Patent · US Expired

Multilayer permanent magnet films

US7050274B2 · kind B2 · utility

2Cited by
34References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 10, 2001
Grant dateMay 23, 2006
Priority date
Expiry dateSep 30, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/3996
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Multilayer permanent magnet films comprising at least two permanent magnet layers separated by an interlayer are disclosed. In one embodiment, the multilayer permanent magnet film includes an interlayer deposited on a first permanent magnet layer, a seed layer deposited on the interlayer, and a second permanent magnet layer deposited on the seed layer. The permanent magnet layers may comprise a material such as CoPt, while the seed layer may comprise a material such as TiW. The interlayer may comprise a material such as Ta. The multilayer permanent magnet films possess favorable properties such as high magnetic coercivity (Hc) and high remnant magnetization (MR) at thicknesses which yield high magnetic fields. The films may be used in applications such as current perpendicular to the plane (CPP) magnetic sensors in which the multilayer permanent magnet film is used to magnetically bias the sensor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.