Magnetic non-volatile memory element

• US 20050207263A1
• Filed: 07/02/2003
• Published: 09/22/2005
• Est. Priority Date: 07/11/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Okayama, Katsumi, Kobayashi, Kaoru, Motoyoshi, Makoto
• Granted Patent: US 7,336,556 B2
• Time in Patent Office: Days
• US Class Current: 365/232
• CPC Class Codes: G11C 11/16 using elements in which the storage effect is based on magnetic spin effect
• CPC Class Codes: H10B 61/22 of the field-effect transistor [FET] type
• CPC Class Codes: Y10S 977/935 Spin dependent tunnel, SDT, junction, e.g. tunneling magnetoresistance, TMR

Abstract

A non-volatile magnetic memory device is proposed, which provides sufficient magnetic shielding performance for external magnetic fields. A first magnetic shield layer 60a and a second magnetic shield layer 60b, both made of a soft magnetic metal, are formed respectively on the bottom surface of the transistor section 20, which is the mounting side of the MRAM device 10, and on the top surface of the bit line 50, which is opposite to the bottom surface of the mounting side of the MRAM device 10. On the second magnetic shield layer 60a, a passivation film 70 is formed. The magnetic flux penetrated from the external magnetic field, is suppressed below the inversion strength of the MRAM device 10, thereby improving reliability. Moreover, by using soft magnetic metal as the magnetic shield layers 60a, 60b, the magnetic shield layers can be formed by the sputtering technique, particularly composing elements can be partly shared as elements of the targets to be used for forming various layers composing the MRAM device 10 by the sputtering technique, thereby enabling to form various layers of the MRAM device 10 in a single sputtering chamber efficiently.

Claims

1. A magnetic non-volatile memory device provided with a magnetic shielding structure for suppressing the influence of external magnetic fields, said device characterized by comprising in that:

a magnetic shield layer made from a soft magnetic metal is formed on a surface of said device for suppressing penetration of magnetic flux into said device, and

said magnetic shield layers are formed on a device surface at the mounting side of said device, and on a device surface opposite to said mounting side of said device.

3. The magnetic non-volatile memory device according to claim 1, said device characterized in that:

said magnetic shield layer is formed of a nano granular structure having a magnetic layer and a non-magnetic layer.

4. The magnetic non-volatile memory device according to claim 1, said device characterized in that:

said magnetic shield layer has a composing element which is common to a part of an element of various layers composing said device.

5. The magnetic non-volatile memory device according to claim 1, said device characterized in that:

a passivation film is formed on said magnetic shield layer.

6. The magnetic non-volatile memory device according to claim 1, said device characterized in that:

said magnetic shield layers formed on a device surface at the mounting side of said device, and a device surface opposite to said mounting side of said device, are magnetically coupled with each other.

7. The magnetic non-volatile memory device according to claim 4, said device characterized in that:

said composing element includes one selected from the group consisting of Fe, Co, Pt, Mn, and Al.

2. (canceled)

8. A method for manufacturing a magnetic non-volatile memory device provided with a magnetic shielding structure for suppressing the influence of external magnetic fields, said method characterized in that:

various layers formed in said device, and a magnetic shield layer formed on a surface of said device for suppressing penetration of magnetic flux into said device are formed in a single sputtering chamber.