Magneto-resistance device including conjugated molecule

Patent metadata

Field	Value
Publication number	US-10553786-B2
Application number	US-201515507254-A
Country	US
Kind code	B2
Filing date	Aug 27, 2015
Priority date	Aug 28, 2014
Publication date	Feb 4, 2020
Grant date	Feb 4, 2020

Abstract

This invention relates to structures comprising magnetic materials and conjugated molecules. The invention relates to magneto-resistive devices based on such structures. Structures and devices of the invention can be used as magnetic switches, magnetic sensors and in devices such in/as memory devices.

First claim

What is claimed is:

1. A magneto-resistive device comprising at least one electrode, said electrode comprising a surface, wherein said surface comprises a ferromagnetic material, wherein said surface is attached to at least one conjugated molecule, such that said molecule is coupled to said surface via π-d hybridization between π molecular orbitals and d orbitals of the ferromagnetic material, wherein said surface is corrugated such that it contains under-coordinated atoms.

2. The magneto-resistive device of claim 1 , wherein said surface is unpassivated.

3. The magneto-resistive device of claim 1 , wherein said electrode comprises Ni, and said conjugated molecules comprise acene or oligoacene molecules.

4. The magneto-resistive device of claim 1 , wherein said device further comprises a second electrode, said second electrode comprises a surface, said surface at least partially facing said first electrode.

5. The magneto-resistive device of claim 4 , wherein one end of said conjugated molecule is attached to said surface of said first electrode and another end of said conjugated molecule is attached to a surface of said second electrode.

6. The magneto-resistive device of claim 5 , wherein said surface of said second electrode comprises a ferromagnetic material, wherein said attachment of said conjugated molecule to said surface comprises coupling of said conjugated molecule to said surface via π-d hybridization between π molecular orbitals of said conjugated molecule and d orbitals of said ferromagnetic material.

7. The magneto-resistive device of claim 4 , wherein said electrodes are configured as crossing wires with said conjugated molecule in between.

8. The magneto-resistive device of claim 4 , wherein said conjugated molecule act as a transport medium between said electrodes, thereby increasing selectivity of spin transport between said electrodes, thus amplifying magnetic effects in said device.

9. The magneto-resistive device of claim 4 , wherein said surfaces of said first and second electrodes comprise a ferromagnetic material and wherein said device further comprises a non-magnetic metal located between said surfaces, such that said device is a giant magneto-resistive (GMR) device.

10. The magneto-resistive device of claim 4 , wherein said surfaces of said first and second electrodes comprise a ferromagnetic material and wherein said device further comprises a dielectric material located between said surfaces, such that said device is a tunneling magneto-resistive (TMR) device.

11. The magneto-resistive device of claim 1 , configured and operable as an anisotropic magneto-resistance (AMR) device characterized by anisotropic magneto-resistance.

12. The magneto-resistive device of claim 1 , wherein said surface is attached to between 1-10 conjugated molecules.

13. The magneto-resistive device of claim 12 , wherein said surface is attached to 1 conjugated molecule.

14. A magnetic memory device, comprising an array of junctions, each formed by a layer of conjugated molecules bridging ferromagnetic surfaces of two electrodes, wherein said conjugated molecule is coupled to the ferromagnetic surface of at least one of the electrodes via π-d hybridization of π molecular orbitals and d orbitals of the ferromagnetic material of said electrode, and wherein said surface of at least one of the electrodes is corrugated such that it contains under-coordinated atoms.

15. A layered magneto-resistive device comprising:
a first magnetic material layer;
a molecular layer comprising a first surface and a second surface; and
a second magnetic material layer;
wherein said first surface of said molecular layer is in contact with said first magnetic material layer and wherein said second surface of said molecular layer is in contact with said second magnetic material layer, such that:
molecules of said first surface are coupled to said first magnetic material layer via π-d hybridization between π molecular orbitals and d orbitals of said magnetic material; and
molecules of said second surface are coupled to said second magnetic material layer via π-d hybridization between π molecular orbitals and d orbitals of said second magnetic material,

and wherein a surface of said first magnetic material layer, of said second magnetic material layer or a combination thereof, coupled to said molecules, is corrugated such that it contains under-coordinated atoms.

16. The device of claim 15 , wherein said organic conjugated molecules comprise acene or oligoacenes.

17. The device of claim 15 , wherein said magnetic material is ferromagnetic or antiferromagnetic.

18. The device of claim 15 , wherein the thickness of said molecular layer ranges between 0.5 nm and 100 nm.

19. The device of claim 15 , wherein said device is anisotropic-magneto-resistance (AMR) device.

20. The device of claim 19 , wherein the magneto-conductance ranges between 10% and 300%.

21. The device of claim 16 , wherein said ferromagnetic material comprises Fe, Ni, Co, oxides thereof, alloys thereof and combinations thereof.

22. A layered magneto-resistive device comprising:
a first magnetic material layer;
a non-magnetic metal layer;
a molecular layer comprising a first surface and a second surface; and
a second magnetic material layer;

wherein said first surface of said molecular layer is in contact with said non-magnetic metal layer and wherein said second surface of said molecular layer is in contact with said second magnetic material layer, such that:
molecules of said first surface are coupled to said non-magnetic metal layer; and
molecules of said second surface are coupled to said second magnetic material layer via π-d hybridization between π molecular orbitals and d orbitals of said magnetic material,

and wherein a surface of said second magnetic material layer, coupled to said molecules, is corrugated such that it contains under-coordinated atoms.

23. The device of claim 22 , wherein said organic conjugated molecules comprise acene or oligoacenes.

24. The device of claim 22 , wherein said magnetic material is ferromagnetic or antiferromagnetic.

25. The device of claim 22 , wherein the thickness of said molecular layer ranges between 0.5 nm and 100 nm.

26. The device of claim 22 wherein said device is giant-magneto-resistance (GMR) device.

27. The device of claim 26 , wherein the magneto-conductance ranges between 10% and 1000%.

28. The device of claim 22 , wherein said ferromagnetic material comprises Fe, Ni, Co, oxides thereof, alloys thereof and combinations thereof.

29. The device of claim 22 , wherein said non-magnetic metal comprises Cu, Ta, Ru, Ag, Ti, Cr, or alloys thereof.

30. A layered magneto-resistive device comprising:
a first magnetic material layer;
a dielectric layer;
a molecular layer comprising a first surface and a second surface; and
a second magnetic material layer;
wherein said first surface of said molecular layer is in contact with said dielectric layer and wherein said second surface of said molecular layer is in contact with said second magnetic material layer, such that:
molecules of said first surface are coupled to said dielectric; and
molecules of said second surface are coupled to said second magnetic material layer via π-d hybridization between π molecular orbitals and d orbitals of said magnetic mater

Assignees

• Yeda Res & Dev

Inventors

• Tal Oren
• Rakhmilevich David

Classifications

• G11B5/3909

  Arrangements using a magnetic tunnel junction · CPC title

• G11C11/161

  details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell · CPC title

• H01F10/329

  Spin-exchange coupled multilayers wherein the magnetisation of the free layer is switched by a spin-polarised current, e.g. spin torque effect · CPC title

• G11C11/15

  using multiple magnetic layers (G11C11/155 takes precedence) · CPC title

• H01F10/002

  Antiferromagnetic thin films, i.e. films exhibiting a Néel transition temperature (H01F10/3218 and H01F10/3268 take precedence) · CPC title