Patent · US Expired

Method of adjusting CoFe free layer magnetostriction

US6998150B2 · kind B2 · utility

72Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 2003
Grant dateFeb 14, 2006
Priority date
Expiry dateNov 12, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49044
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

It has been found that the insertion of a copper laminate within CoFe, or a CoFe/NiFe composite, leads to higher values of CPP GMR and DRA. However, this type of structure exhibits very negative magnetostriction, in the range of high −10−6 to −10−5. This problem has been overcome by giving the copper laminates an oxygen exposure treatment When this is done, the free layer is found to have a very low positive magnetostriction constant. Additionally, the value of the magnetostriction constant can be adjusted by varying the thickness of the free layer and/or the position and number of the oxygen treated copper laminates.

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