Magnetoresistive (MR) sensors employing dual MR devices for differential MR sensing
US10060880B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 2016 |
| Grant date | Aug 28, 2018 |
| Priority date | — |
| Expiry date | Jan 6, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/098
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Magnetoresistive (MR) sensors employing dual MR devices for differential MR sensing are provided. These MR sensors may be used as biosensors to detect the presence of biological materials as an example. An MR sensor includes dual MR sensor devices that may be tunnel magnetoresistive (TMR) devices or giant magnetoresistive (GMR) devices as examples. The MR devices are arranged such that a channel is formed between the MR devices for receiving magnetic nanoparticles. A magnetic stray field generated by the magnetic nanoparticles causes free layers in the MR devices to rotate in opposite directions, thus causing differential resistances between the MR devices for greater sensing sensitivity. Further, as another aspect, by providing the channel between the MR devices, the magnetic stray field generated by the magnetic nanoparticles can more easily rotate the magnetic moment orientation of the free layers in the MR devices, thus further increasing sensitivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.