Magnetic memory devices including magnetic memory cells having opposite magnetization directions

Patent metadata

Field	Value
Publication number	US-9330745-B2
Application number	US-201414509756-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Dec 24, 2013
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

A magnetic memory device includes first and second magnetic memory cells coupled to first and second bit lines, respectively. The first and second magnetic memory cells respectively include a pinned magnetic layer, a free magnetic layer, and a tunnel insulating layer therebetween. Respective stacking orders of the pinned magnetic layer, the tunnel insulating layer, and the free magnetic layer are different in the first and second magnetic memory cells. The magnetic memory device further includes at least one transistor that is configured to couple the first and second magnetic memory cells to a common source line. Related methods of operation are also discussed.

First claim

What is claimed is:

1. A magnetic memory device comprising:
a first bit line and a second bit line that is adjacent the first bit line;
a first word line crossing the first and second bit lines;
a first magnetic memory cell disposed adjacent an intersection of the first bit line and the first word line; and
a second magnetic memory cell disposed adjacent an intersection of the second bit line and the first word line,
wherein the first and second magnetic memory cells respectively include a first magnetic layer, a tunnel insulating layer, and a second magnetic layer, and
wherein respective stacking orders of the first magnetic layer, the tunnel insulating layer, and the second magnetic layer are different in the first and second magnetic memory cells, wherein respective distances between the first and second magnetic memory cells and a substrate are different from each other, and wherein the respective distances between the first and second magnetic memory cells and the substrate are greater than a distance between the first word line and the substrate.

2. The magnetic memory device of claim 1 , wherein the first magnetic layer, the tunnel insulating layer, and the second magnetic layer are sequentially stacked in the first magnetic memory cell, and wherein the second magnetic layer, the tunnel insulating layer, and the first magnetic layer are sequentially stacked in the second magnetic memory cell.

3. The magnetic memory device of claim 1 , further comprising:
a transistor connected to the first word line and a source line,
wherein the first and second magnetic memory cells are connected to a drain region of the transistor, and the source line is connected to a source region of the transistor.

4. The magnetic memory device of claim 3 , further comprising:
a first vertical contact plug coming in contact with the drain region and extending in a first direction;
a horizontal contact plug in contact with the first vertical contact plug and extending in a second direction; and
a second vertical contact plug in contact with the horizontal contact plug and extending in the first direction,
wherein the first magnetic memory cell contacts a first pad disposed on an upper surface of the horizontal contact plug, and the second magnetic memory cell contacts a second pad disposed on an upper surface of the second vertical contact plug.

5. The magnetic memory device of claim 3 , further comprising:
a plurality of the first word lines; and
a plurality of the first and second magnetic memory cells disposed adjacent respective intersections of the first word lines and the first and second bit lines, respectively.

6. The magnetic memory device of claim 5 , wherein a number of the first magnetic memory cells is equal to a number of the second magnetic memory cells.

7. The magnetic memory device of claim 1 , further comprising:
first and second transistors respectively connected to the first word line and a source line,
wherein the first and second memory cells are connected to respective drain regions of the first and second transistors, wherein the first and second transistors share a source region, and wherein the source line is connected to the source region.

8. The magnetic memory device of claim 1 , wherein a magnetization direction of the first magnetic layer is pinned, and wherein a magnetization direction of the second magnetic layer is changeable.

9. A magnetic memory device comprising:
first and second bit lines that are adjacent one another;
a first word line crossing the first and second bit lines;
a first magnetic memory cell disposed adjacent an intersection of the first bit line and the first word line, the first magnetic memory cell including a first magnetic layer, a tunnel insulating layer, and a second magnetic layer sequentially stacked;
a second magnetic memory cell disposed adjacent an intersection of the second bit line and the first word line, the second magnetic memory cell including a second magnetic layer, a tunnel insulating layer, and a first magnetic layer sequentially stacked; and
a source line electrically connected to the first and second magnetic memory cells,
wherein respective magnetization directions of the second magnetic layer of the first magnetic memory cell and the second magnetic layer of the second magnetic memory cell are different from each other, wherein respective distances between the first and second magnetic memory cells and a substrate are different from each other, and wherein the respective distances between the first and second magnetic memory cells and the substrate are greater than a distance between the first word line and the substrate.

10. The magnetic memory device of claim 9 , wherein respective magnetization directions of the first magnetic layer of the first and second magnetic memory cells are pinned, and wherein the respective magnetization directions of the second magnetic layer of the first and second magnetic memory cells are changeable.

11. The magnetic memory device of claim 9 , wherein the memory device is configured such that the respective magnetization directions of the second magnetic layer of the first and second magnetic memory cells are different responsive to a same voltage applied to the first and second bit lines.

12. The magnetic memory device of claim 11 , wherein the memory device is configured such that, responsive to application of a power supply voltage to the first word line, a first current flows between the first bit line and the source line through the first magnetic memory cell, and a second current flows between the second bit line and the source line through the second magnetic memory cell in a same direction as the first current.

13. The magnetic memory device of claim 9 , further comprising:
a transistor connected to the first word line,
wherein the first and second memory cells are connected to a drain region of the transistor, and wherein the source line is connected to a source region of the transistor.

14. A magnetic memory device, comprising:
first and second magnetic memory cells coupled to first and second bit lines, respectively, the first and second magnetic memory cells respectively including a pinned magnetic layer, a free magnetic layer, and a tunnel insulating layer therebetween; and
at least one transistor configured to couple the first and second magnetic memory cells to a common source line,
wherein respective stacking orders of the pinned magnetic layer, the tunnel insulating layer, and the free magnetic layer are different in the first and second magnetic memory cells, wherein respective distances between the first and second magnetic memory cells and a substrate are different from each other, and wherein the respective distances between the first and second magnectic memory cells and the substrate are greater than a distance between the first word line and the substrate.

15. The device of claim 14 , wherein the first and second magnetic memory cells have different resistances, and wherein a comparison of the different resistances is indicative of binary data.

16. The device of claim 15 , wherein the memory device is configured such that the free magnetic layer of the first magnetic memory cell and the free magnetic layer of the second magnetic memory cell have opposite magnetization directions responsive to application of a same voltage to the first and second bit lines, and the pinned magnetic layer of the first and second magnetic memory cells have a same magnetization direction.

17. The device of claim 14 , wherein the at least one transistor comp

Assignees

• Seo Bo-Young
• Lee Yong-Kyu
• Lee Choong-Jae
• Jeon Hee-Seog
• Samsung Electronics Co Ltd

Inventors

• Seo Bo-Young
• Lee Yong-Kyu
• Lee Choong-Jae
• Jeon Hee-Seog

Classifications

• G11C11/161 Primary

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

• G11C11/1675

  Writing or programming circuits or methods · CPC title

• G11C11/1659

  Cell access · CPC title

• G11C11/1655

  Bit-line or column circuits · CPC title

• G11C11/1673

  Reading or sensing circuits or methods · CPC title