Patent · US Expired

Spin-valve magnetoresistance sensor and thin film magnetic head

US6340533B1 · kind B1 · utility

174Cited by
12References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 19, 1999
Grant dateJan 22, 2002
Priority date
Expiry dateNov 19, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/12937
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A synthetic-type spin-valve MR sensor having a pinned magnetic layer with a multi-layer film structure. In one embodiment, on a substrate are formed by layering a free magnetic layer, a pinned magnetic layer including first and second ferromagnetic films, which are mutually coupled antiferromagnetically and which enclose a nonmagnetic coupling film. A nonmagnetic conductive layer is enclosed between these two magnetic layers. An antiferromagnetic layer neighbors the pinned magnetic layer. The first ferromagnetic film neighboring the antiferromagnetic layer is formed from a high-resistivity Co-base material. By making the products of the saturation magnetization and the film thickness of the first ferromagnetic layer and the second ferromagnetic layer substantially equal, the apparent magnetic moment of the pinned magnetic layer as a whole is zero, and the magnetostatic action on the free magnetic layer is eliminated or reduced. Shunting of the sense current to the first ferromagnetic film is suppressed, and a high rate of magnetoresistive change is obtained.

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