IP Library Granted Patent US 11,758,739
Granted Patent B2
US 11,758,739 · App. 17/371,138 · Granted Sep 12, 2023

Magnetic memory device

Inventors: Masayoshi Iwayama (Seoul, KR); Tatsuya Kishi (Seongnam-si, KR); Masahiko Nakayama (Kawasaki Kanagawa, JP); Toshihiko Nagase (Tokyo, JP); Daisuke Watanabe (Yokkaichi Mie, JP); Tadashi Kai (Tokyo, JP)
Assignee: Kioxia Corporation
H10B61/10H10N50/01H10N50/80H10N50/85
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Quick Facts
Patent No.
US 11,758,739
App. No.
17/371,138
Granted
Sep 12, 2023
Kind
B2
Abstract

A magnetic memory device including a first memory cell which includes a first stacked structure including a magnetic layer and a second memory cell which is provided on the first memory cell and includes a second stacked structure including a magnetic layer. Each of the first stacked structure and the second stacked structure includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer. A concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure and a concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure are different from each other.

Claims (18)

1. A magnetic memory device comprising:

a first memory cell which includes a first stacked structure including a magnetic layer; and

a second memory cell which is provided on the first memory cell and includes a second stacked structure including a magnetic layer,

wherein:

each of the first stacked structure and the second stacked structure includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, and

a concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure is different from a concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure.

2. The magnetic memory device according to claim 1 , wherein:

both the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure and the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure are higher than 90% and less than 100%, and

the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure is lower than the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure.

3. The magnetic memory device according to claim 1 , wherein:

both the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure and the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure are in a range from 50% to 75%, and

the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure is lower than the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure.

4. The magnetic memory device according to claim 1 , wherein:

both the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure and the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure are in a range from 75% to 90%, and

the concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure is higher than the concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure.

5. The magnetic memory device according to claim 1 , wherein:

the first memory cell further includes a first switching element connected to the first stacked structure, and

the second memory cell further includes a second switching element connected to the second stacked structure.

Assignments (2)
CHANGE OF NAME Recorded Feb 15, 2022
From: TOSHIBA MEMORY CORPORATION
To: KIOXIA CORPORATION
Reel/Frame 059110/0850 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 9, 2021
From: IWAYAMA, MASAYOSHI; KISHI, TATSUYA; NAKAYAMA, MASAHIKO; NAGASE, TOSHIHIKO; WATANABE, DAISUKE; KAI, TADASHI
To: TOSHIBA MEMORY CORPORATION
Reel/Frame 056798/0101 →
Priority Claims (1)
JP 2018-173557 · Sep 18, 2018 · national
Continuity (2)
Division 16353069 · Mar 14, 2019
Related Publication 20210335888A1 · Oct 28, 2021