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Double MgO-based Perpendicular Magnetic-Tunnel-Junction Spin-valve Structure with a Top Co2Fe6B2 Free Layer using a Single SyAF [Co/Pt]n Layer.

ABSTRACT: A new perpendicular spin-transfer-torque magnetic-tunnel-junction (p-MTJ) spin-valve was developed to achieve a high tunneling magnetoresistance (TMR) ratio. It had a double MgO-based spin-valve structure with a top Co2Fe6B2 free layer and incorporated a single SyAF [Co(0.4?nm)/Pt(0.3?nm)]3 layer and a new buffer layer of Co(0.6)/Pt(0.3)/Co(0.4). It had a TMR ratio of 180% and anisotropy exchange field (H ex ) of 3.44?kOe after ex-situ annealing of 350?°C for 30?min under a vacuum below 10-6 torr and a perpendicular magnetic field of 3 tesla, thereby ensuring a memory margin and avoiding read disturbance failures. Its high level of performance was due to the face-center-cubic crystallinity of the MgO tunneling barrier being significantly improved by decreasing its surface roughness (i.e., peak-to-valley length of 1.4?nm).

SUBMITTER: Choi JY

PROVIDER: S-EPMC5794754 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Double MgO-based Perpendicular Magnetic-Tunnel-Junction Spin-valve Structure with a Top Co2Fe6B2 Free Layer using a Single SyAF [Co/Pt]n Layer.

Choi Jin-Young JY Lee Dong-Gi DG Baek Jong-Ung JU Park Jea-Gun JG

Scientific reports 20180201 1

A new perpendicular spin-transfer-torque magnetic-tunnel-junction (p-MTJ) spin-valve was developed to achieve a high tunneling magnetoresistance (TMR) ratio. It had a double MgO-based spin-valve structure with a top Co2Fe6B2 free layer and incorporated a single SyAF [Co(0.4 nm)/Pt(0.3 nm)]3 layer and a new buffer layer of Co(0.6)/Pt(0.3)/Co(0.4). It had a TMR ratio of 180% and anisotropy exchange field (H ex ) of 3.44 kOe after ex-situ annea ...[more]

PMID: 29391577

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