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Double Pinned Perpendicular-Magnetic-Tunnel-Junction Spin-Valve Providing Multi-level Resistance States.

ABSTRACT: A new design for high density integration greater than gigabits of perpendicular-magnetic-tunnel-junction (p-MTJ) spin-valve, called the double pinned (i.e., bottom and top pinned structures) p-MTJ spin-valve achieved a multi-level memory-cell operation exhibiting four-level resistances. Three key magnetic properties, the anisotropy exchange field (H_ex) of the bottom pinned structure, the coercivity (H_c) of the double free-layer, and the H_c of the top pinned structure mainly determined four-level resistances producing tunneling-magnetoresistance (TMR) ratios of 152.6%, 33.6%, and 166.5%. The three key-design concepts are: i) the bottom pinned structure with a sufficiently large H_ex to avoid a write-error, ii) the H_c of the double free-layer (i.e., ~0.1?kOe) much less than the H_c of the top pinned structure (i.e., ~1.0?kOe), and iii) the top pinned structure providing different electron spin directions.

SUBMITTER: Choi JY

PROVIDER: S-EPMC6695488 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Double Pinned Perpendicular-Magnetic-Tunnel-Junction Spin-Valve Providing Multi-level Resistance States.

Choi Jin-Young JY Jun Hansol H Ashiba Kei K Baek Jong-Ung JU Shim Tae-Hun TH Park Jea-Gun JG

Scientific reports 20190815 1

A new design for high density integration greater than gigabits of perpendicular-magnetic-tunnel-junction (p-MTJ) spin-valve, called the double pinned (i.e., bottom and top pinned structures) p-MTJ spin-valve achieved a multi-level memory-cell operation exhibiting four-level resistances. Three key magnetic properties, the anisotropy exchange field (Hex) of the bottom pinned structure, the coercivity (Hc) of the double free-layer, and the Hc of the top pinned stru ...[more]

PMID: 31417114

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