Magnetoresistive element and nonvolatile solid-state memory using the same

• US 20030067800A1
• Filed: 10/01/2002
• Published: 04/10/2003
• Est. Priority Date: 10/02/2001
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Koganei, Akio
• Granted Patent: US 6,987,652 B2
• Time in Patent Office: Days
• US Class Current: 365/158
• CPC Class Codes: G11C 11/15 using multiple magnetic layers G11C11/155 takes precedence

Abstract

The present invention provides a magnetoresistive element in which a first magnetic layer and a second magnetic layer whose coercive forces are different, and a non-magnetic layer that is disposed between the magnetic layers, wherein edges of the magnetoresistive element are tapered, or a magnetoresistive element in which a first magnetic layer and a second magnetic layer, and a non-magnetic layer that is disposed between the magnetic layers, wherein the coercive force of the first magnetic layer is larger than the coercive force of the second magnetic layer, and wherein relation between a base area S1 of the first magnetic layer and a base area S2 of the second magnetic layer is S1>S2.

Claims

1. A magnetoresistive element comprising a first magnetic layer and a second magnetic layer whose coercive forces are different, and a non-magnetic layer disposed between the magnetic layers, wherein edges of the magnetoresistive element have tapered angle.

2. The magnetoresistive element according to claim 1, wherein an easy magnetization axis of the first magnetic layer and the second magnetic layer is in a direction vertical to a film surface.

3. The magnetoresistive element according to claim 1, wherein the non-magnetic layer is an insulator.

4. The magnetoresistive element according to claim 2, wherein the first magnetic layer or the second magnetic layer is made of a rare-earth transition metal alloy.

5. The magnetoresistive element according to claim 1, wherein a magnetic layer containing at least one element of Fe and Co is provided between at least either the first magnetic layer and the non-magnetic layer, or the second magnetic layer and the non-magnetic layer.

6. The magnetoresistive element according to claim 1, wherein the tapered angle is in the range of 30°

to 70°

.

12. Nonvolatile solid-state memory in which the magnetoresistive elements according to claim 1 are formed in a matrix as memory elements on a substrate, comprising a bit line connected to the magnetoresistive elements, a write line to change a magnetization direction of the first magnetic layer or the second magnetic layer by a magnetic field generated by a current, and switching elements connected to the memory elements.

13. The nonvolatile solid-state memory according to claim 12, wherein the switching element is constituted by a field-effect transistor, and wherein the magnetoresistive element is formed on a drain region of the transistor.

7. A magnetoresistive element comprising a first magnetic layer and a second magnetic layer, and a non-magnetic layer disposed between the magnetic layers, wherein coercive force of the first magnetic layer is larger than coercive force of the second magnetic layer, and wherein the relation between a base area S1 of the first magnetic layer and a base area S2 of the second magnetic layer is S1>

S2.

8. The magnetoresistive element according to claim 7, wherein an easy magnetization axis of the first magnetic layer and the second magnetic layer is in a direction vertical to a film surface.

9. The magnetoresistive element according to claim 7, wherein the non-magnetic layer is an insulator.

10. The magnetoresistive element according to claim 8, wherein the first magnetic layer or the second magnetic layer is made of a rare-earth transition metal alloy.

11. The magnetoresistive element according to claim 9, wherein a magnetic layer containing at least one element of Fe and Co is provided between at least either the first magnetic layer and the non-magnetic layer, or the second magnetic layer and the non-magnetic layer.

14. Nonvolatile solid-state memory in which the magnetoresistive elements according to claim 7 are formed in a matrix as memory elements on a substrate, comprising a bit line connected to the magnetoresistive elements, a write line to change a magnetization direction of the first magnetic layer or the second magnetic layer by a magnetic field generated by a current, and switching elements connected to the memory elements.

15. The nonvolatile solid-state memory according to claim 14, wherein the switching element is constituted by a field-effect transistor, and wherein the magnetoresistive element is formed on a drain region of the transistor.