Tunneling magnetic sensor including free magnetic layer and magnesium protective layer disposed thereon
US7933100B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2007 |
| Grant date | Apr 26, 2011 |
| Priority date | — |
| Expiry date | Feb 13, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F10/3272
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A tunneling magnetic sensor includes a pinned magnetic layer of which the magnetization is pinned in one direction, an insulating barrier layer, and a free magnetic layer of which the magnetization is varied by an external magnetic field, these layers being arranged in that order from the bottom. A first protective layer made of magnesium (Mg) is disposed on the free magnetic layer. The tunneling magnetic sensor has a larger change in reluctance as compared to conventional magnetic sensors including no first protective layers or including first protective layers made of Al, Ti, Cu, or an Ir—Mn alloy. The free magnetic layer has lower magnetostriction as compared to free magnetic layers included in the conventional magnetic sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.