Patent · US Expired

Magnetoresistive read transducer and method for making the improved transducer

US4809109A · kind A · utility

51Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1988
Grant dateFeb 28, 1989
Priority date
Expiry dateMar 25, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/12465
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An improved magnetoresistive (MR) read transducer in which a layered structure comprising an antiferromagnetic layer in direct contact with an MR layer is subjected to a thermal annealing process by heating the structure to a temperature within a chosen range for a chosen time so that a new ternary antiferromagnetic alloy is formed by diffusion. The ternary antiferromagnetic alloy has a high value of exchange bias which is less temperature sensitive. In a specific embodiment in which the MR layer is NiFe and the antiferromagnetic layer is FeMn, the ternary alloy formed by heating the structure to a temperature within the range of 260.degree. C. to 350.degree. C. for 50 to 20 hours has a room temperature exchange bias field with NiFe of about 50 Oersted and an ordering temperature which exceeds 300.degree. C.

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