Method of characterizing exchange coupling for magnetoresistive sensor
US5776537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1997 |
| Grant date | Jul 7, 1998 |
| Priority date | — |
| Expiry date | Feb 5, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/093
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
An MR sensor includes an MR layer and permanent magnets defining an active area on the MR layer. A bi-layer test structure is fabricated with a permanent magnet layer deposited on a substrate and an MR layer deposited on the permanent magnet layer. If desired, a SAL may be deposited prior to deposition of the permanent magnet layer. A DC magnetic field is applied to the bi-layer test structure, and the strength of the DC magnetic field is varied. During application of the DC magnetic field, the magnetic response of the bi-layer test structure is measured to determine a hysteresis loop of the bi-layer structure. The exchange coupling between the permanent magnet layer and the MR layer is characterized by a point of inflection identified on the measured hysteresis loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.