The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 26, 2008
Filed:
Jul. 02, 2003
Katsumi Okayama, Kanagawa, JP;
Kaoru Kobayashi, Chiba, JP;
Makoto Motoyoshi, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A non-volatile magnetic memory device is proposed, which provides sufficient magnetic shielding performance for external magnetic fields. A first magnetic shield layerand a second magnetic shield layer, both made of a soft magnetic metal, are formed respectively on the bottom surface of the transistor section, which is the mounting side of the MRAM device, and on the top surface of the bit line, which is opposite to the bottom surface of the mounting side of the MRAM device. On the second magnetic shield layer, a passivation filmis formed. The magnetic flux penetrated from the external magnetic field, is suppressed below the inversion strength of the MRAM device, thereby improving reliability. Moreover, by using soft magnetic metal as the magnetic shield layers, 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 deviceby the sputtering technique, thereby enabling to form various layers of the MRAM devicein a single sputtering chamber efficiently.