Magnetic etch stop layer for spin-transfer torque magnetoresistive random access memory magnetic tunnel junction device

Patent metadata

Field	Value
Publication number	US-9620706-B2
Application number	US-201414558103-A
Country	US
Kind code	B2
Filing date	Dec 2, 2014
Priority date	Dec 2, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

An apparatus includes a capping layer disposed on top of a free layer. The apparatus also includes a magnetic etch stop layer disposed on top of the capping layer. The capping layer and the magnetic etch stop layer are included in a spin-transfer torque magnetoresistive random access memory (STT-MRAM) magnetic tunnel junction (MTJ) device.

First claim

What is claimed is:

1. An apparatus comprising:
a capping layer disposed on top of a free layer;
a magnetic layer disposed on top of the capping layer; and
an electrode layer disposed between the magnetic layer and a hard mask layer, wherein the capping layer and the magnetic layer are included in a spin-transfer torque magnetoresistive random access memory (STT-MRAM) magnetic tunnel junction (MTJ) device.

2. The apparatus of claim 1 , wherein the capping layer is comprised of Magnesium Oxide, Aluminum Oxide, Hafnium Oxide, or Tantalum Oxide.

3. The apparatus of claim 1 , wherein the magnetic layer is comprised of Cobalt Iron Boron, Cobalt Iron, Iron Boron, Nickel Iron Boron, Nickel Iron Silicon Boron, or Nickel Iron.

4. The apparatus of claim 1 , wherein a thickness of the magnetic layer causes the magnetic etch stop layer to be substantially magnetically inert.

5. The apparatus of claim 4 , wherein the thickness of the magnetic layer is less than 5 Angstroms.

6. The apparatus of claim 4 , wherein the thickness of the magnetic layer is approximately 5 Angstroms.

7. The apparatus of claim 1 , wherein the STT-MRAIVI MTJ device is a perpendicular MTJ device.

8. The apparatus of claim 7 , wherein a thickness of the magnetic layer causes the magnetic layer to introduce in-plane anisotropy to the STT-MRAM MTJ device.

9. The apparatus of claim 8 , wherein the thickness of the magnetic layer is between approximately 10 Angstroms and 30 Angstroms.

10. An apparatus comprising:
first means for protecting a free layer disposed on top of the free layer;
second means for protecting the free layer, the second means disposed on top of the first means for protecting, wherein the second means comprises a magnetic material; and
means for conducting disposed between the second means and means for masking, wherein the first means and the second means are included in a spin-transfer torque magnetoresistive random access memory (STT-MRAM) magnetic tunnel junction (MTJ) device.

11. The apparatus of claim 10 , wherein the first means for protecting is comprised of Magnesium Oxide, Aluminum Oxide, Hafnium Oxide, or Tantalum Oxide.

12. The apparatus of claim 10 , wherein the second means for protecting is comprised of Cobalt Iron Boron, Cobalt Iron, Iron Boron, Nickel Iron Boron, Nickel Iron Silicon Boron, or Nickel Iron.

13. The apparatus of claim 10 , wherein a thickness of the second means for protecting causes the second means for protecting to be substantially magnetically inert.

14. The apparatus of claim 13 , wherein the thickness of the second means for protecting is less than 5 Angstroms.

15. The apparatus of claim 13 , wherein the thickness of the second means for protecting is approximately 5 Angstroms.

16. The apparatus of claim 10 , wherein the STT-MRAIVI MTJ device is a perpendicular MTJ device.

17. The apparatus of claim 16 , wherein a thickness of the second means for protecting causes the second means for protecting to introduce in-plane anisotropy to the STT-MRAM MTJ device.

18. The apparatus of claim 17 , wherein the thickness of the second means for protecting is greater than approximately 10 Angstroms.

19. A perpendicular spin-transfer torque magnetoresistive random access memory (STT-MRAM) magnetic tunnel junction (MTJ) device comprising:
a Magnesium Oxide (MgO) capping layer disposed on top of a free layer; and
a 5-Angstrom thick Cobalt Iron Boron (CoFeB) magnetic layer disposed on top of the MgO capping layer; and
an electrode layer disposed between the 5-Angstrom thick Cobalt Iron Boron (CoFeB) magnetic layer and a hard mask layer.

20. The perpendicular STT-MRAM MTJ device of claim 19 , wherein the 5-Angstrom thick CoFeB magnetic layer is substantially magnetically inert.

21. The apparatus of claim 1 , wherein the capping layer is comprised of Magnesium Oxide.

22. The apparatus of claim 1 , wherein the capping layer is comprised of Aluminum Oxide.

23. The apparatus of claim 1 , wherein the capping layer is comprised of Hafnium Oxide.

24. The apparatus of claim 1 , wherein the capping layer is comprised of Tantalum Oxide.

25. The apparatus of claim 1 , wherein the magnetic layer is comprised of Cobalt Iron Boron.

26. The apparatus of claim 1 , wherein the magnetic layer is comprised of Cobalt Iron.

27. The apparatus of claim 1 , wherein the magnetic layer is comprised of Iron Boron.

28. The apparatus of claim 1 , wherein the magnetic layer is comprised of Nickel Iron Boron.

29. The apparatus of claim 1 , wherein the magnetic layer is comprised of Nickel Iron Silicon Boron.

30. The apparatus of claim 1 , wherein the magnetic layer is comprised of Nickel Iron.

Assignees

• Qualcomm Inc

Inventors

• Lee Kangho
• Park Chando
• Kan Jimmy
• Gottwald Matthias Georg
• Zhu Xiaochun
• Kang Seung Hyuk

Classifications

• H01L43/12

  Electricity · mapped topic

• H01L43/08 Primary

  Electricity · mapped topic

• H10N50/10 Primary

  Magnetoresistive devices · CPC title

• H10N50/01

  Manufacture or treatment · CPC title