Low resistance magnetic tunnel junction device with bilayer or multilayer tunnel barrier
US6347049B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2001 |
| Grant date | Feb 12, 2002 |
| Priority date | — |
| Expiry date | Jul 25, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/3996
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A low resistance magnetic tunnel junction (MTJ) device has a bilayer or multilayer as the insulating tunnel barrier. In one embodiment the tunnel barrier is a bilayer of a first layer of magnesium oxide on the bottom magnetic electrode and an aluminum oxide layer on the magnesium oxide layer. This bilayer is formed by oxidizing a bilayer of Mg/Al. In a second embodiment the tunnel barrier is a bilayer of first layer of aluminum nitride and a second layer of aluminum oxide on top of the aluminum nitride first layer, with this bilayer formed by oxidizing a bilayer of AlN/Al. MTJ devices with trilayer barriers, such as AlN/Al2O3/AlN, MgO/Al2O3/MgO and Al2O3/MgO/Al2O3 are also possible. The resulting magnetic tunnel junction devices have resistance-area values less than 1000 &OHgr;(&mgr;m)2 and preferably in the range of 0.1 to 100 &OHgr;(&mgr;m)2, making the devices suitable for magnetic read sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.