Magnetic field sensor with perpendicular axis sensitivity, comprising a giant magnetoresistance material or a spin tunnel junction
US6577124B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1999 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Aug 13, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F10/3254
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thin film magnetic field sensor with perpendicular axis sensitivity uses either a giant magnetoresistance material element or a spin tunnel junction element. The sensor element has ferromagnetic layers which have strongly different uniaxial anisotropies and/or a modified magnetization curve, achieved by antiferromagnetic exchange coupling with an auxiliary ferromagnetic layer. A strongly miniaturizable sensor has four spin tunnel junction elements connected to form a Wheatstone bridge. The magnetically sensitive element functions equally as well as a laminated flux concentrator, resulting in a low noise single domain configuration. The very simple design also allows easy definition of the fixed magnetization direction of a counter electrode. Very high output voltage combined with very low power is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.