Patent · US Expired

Multilayered magnetic sensor having conductive layer within megnetic layer

US5838154A · kind A · utility

129Cited by
3References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 14, 1996
Grant dateNov 17, 1998
Priority date
Expiry dateMar 14, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A magnetic sensor element 1 includes a substrate 10, a conductive layer 12 of a conductive material, and a magnetic layer 11 of a magnetic material, which encloses the conductive layer 12. AC is applied to the element from a drive power source 50, and a detector 60 detects an impedance change due to an external magnetic field. The magnetic layer 11 is bestowed with magnetic anisotropy in a direction orthogonal to the direction of energization of the element 1. With the provision of the conductive layer 12 of conductive material and also with magnetic anisotropy imparted to the magnetic layer 1, the element 1 may be made a low resistivity element. A reactance change and a resistance change of the element due to an external magnetic field change, thus can be effectively detected in drive frequencies two orders of magnitude lower than in the case of a prior art magnetic sensor element. The magnetic anisotropy of the magnetic layer 11 is controlled to prevent magnetic field detection dynamic range variations with drive frequency.

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