Magnetic random access memory with ultrathin reference layer
View Patent ↗The present invention is directed to a magnetic memory element including a magnetic free layer and a first magnetic reference layer with an insulating tunnel junction layer interposed therebetween; a second magnetic reference layer made of a material comprising cobalt and formed adjacent to the first magnetic reference layer opposite the insulating tunnel junction layer; an iridium layer formed adjacent to the second magnetic reference layer opposite the first magnetic reference layer; and a magnetic fixed layer formed adjacent to the iridium layer. The magnetic free layer has a variable magnetization direction substantially perpendicular to the layer plane thereof. The first and second magnetic reference layers have a first fixed magnetization direction substantially perpendicular to the layer planes thereof. The magnetic fixed layer has a second fixed magnetization direction that is substantially perpendicular to the layer plane thereof and is substantially opposite to the first fixed magnetization direction.
1. A magnetic memory element including:
a magnetic free layer and a first magnetic reference layer with an insulating tunnel junction layer interposed therebetween;
a second magnetic reference layer formed adjacent to said first magnetic reference layer opposite said insulating tunnel junction layer, said second magnetic reference layer is made of a magnetic material comprising cobalt;
an iridium layer formed adjacent to said second magnetic reference layer opposite said first magnetic reference layer; and
a magnetic fixed layer formed adjacent to said iridium layer opposite said second magnetic reference layer,
wherein said magnetic free layer has a variable magnetization direction substantially perpendicular to a plane of said magnetic free layer, said first and second magnetic reference layers have a first fixed magnetization direction substantially perpendicular to layer planes of said first and second magnetic reference layers, said magnetic fixed layer has a second fixed magnetization direction that is substantially perpendicular to a layer plane of said magnetic fixed layer and is substantially opposite to said first fixed magnetization direction.
2. The magnetic memory element according to claim 1 , wherein said magnetic free layer is made of a magnetic material comprising cobalt, iron, and boron.
3. The magnetic memory element according to claim 1 , wherein said magnetic free layer is made of a magnetic material comprising cobalt, iron, and tantalum.
4. The magnetic memory element according to claim 1 , wherein said magnetic free layer is made of a magnetic material comprising cobalt, iron, and molybdenum.
5. The magnetic memory element according to claim 1 , wherein said first magnetic reference layer is made of a magnetic material comprising cobalt, iron, and boron.
6. The magnetic memory element according to claim 1 , wherein said first magnetic reference layer is made of a magnetic material comprising cobalt, iron, and tantalum.
7. The magnetic memory element according to claim 1 , wherein said first magnetic reference layer is made of a magnetic material comprising cobalt, iron, and molybdenum.
8. The magnetic memory element according to claim 1 , wherein said magnetic material of said second magnetic reference layer further comprises iron.
9. The magnetic memory element according to claim 1 , wherein said magnetic material of said second magnetic reference layer further comprises platinum.
10. The magnetic memory element according to claim 1 , wherein said magnetic material of said second magnetic reference layer further comprises iron and boron.
11. The magnetic memory element according to claim 1 , wherein said magnetic material of said second magnetic reference layer further comprises iron and molybdenum.
12. The magnetic memory element according to claim 1 , wherein said magnetic material of said second magnetic reference layer further comprises iron and tantalum.
13. The magnetic memory element according to claim 1 , wherein said magnetic fixed layer is made of a magnetic material comprising cobalt and platinum.
14. The magnetic memory element according to claim 1 , wherein said magnetic fixed layer is made of a magnetic material comprising iron and platinum.
15. The magnetic memory element according to claim 1 , wherein said magnetic fixed layer has a multilayer structure formed by interleaving one or more layers of a first type material with one or more layers of a second type material, at least one of said first type and second type materials being magnetic.
16. The magnetic memory element according to claim 15 , wherein said first type material is cobalt.
17. The magnetic memory element according to claim 15 , wherein said second type material is nickel.
18. The magnetic memory element according to claim 15 , wherein said second type material is platinum or palladium.