MgO/CoFeB/Ta/CoFeB/MgO Recording Structure in Magnetic Tunnel Junctions With Perpendicular Easy Axis

Author

Sato, Hikaru ; Yamanouchi, Masato ; Ikeda, Shoji ; Fukami, Shunsuke ; Matsukura, Fumihiro ; Ohno, Hideo

Author_Institution

Center for Spintronics Integrated Syst., Tohoku Univ., Sendai, Japan

Volume

49

Issue

7

fYear

2013

fDate

Jul-13

Firstpage

4437

Lastpage

4440

Abstract

Junction size (D) dependence of thermal stability (Δ) factor and intrinsic critical current (I_C0) were investigated for MgO/CoFeB/Ta/CoFeB/MgO recording structure in magnetic tunnel junctions (MTJs) having a CoFeB reference layer and a synthetic ferrimagnetic (SyF) reference layer. Δ of the recording structure shows almost constant value down to 40 nm, whereas I_C0 shows a linear dependence on the recording layer area, as similarly observed in recording structure with single-interface. Average absolute intrinsic critical current density is 3.5 MA/cm², which is comparable to previously reported value for recording structure with single-interface. A MgO/CoFeB(1.4)/Ta(0.4)/CoFeB(1.0)/MgO double-interface recording structure in MTJ with SyF reference layer shows Δ of 59 at D = 29 nm.

Keywords

cobalt compounds; critical currents; ferrimagnetic materials; iron compounds; magnesium compounds; magnetic multilayers; magnetic structure; magnetic tunnelling; perpendicular magnetic anisotropy; perpendicular magnetic recording; tantalum; thermal stability; MgO-CoFeB-Ta-CoFeB-MgO; double interface recording structure; intrinsic critical current density; junction size dependence; magnetic magnetic anisotropy; magnetic tunnel junctions; multilayers; perpendicular easy axis; reference layer; single interface; size 0.4 nm; size 1.4 nm; synthetic ferrimagnetic reference layer; thermal stability factor; Junctions; Magnetic multilayers; Magnetic recording; Magnetic tunneling; Perpendicular magnetic anisotropy; Switches; Intrinsic critical current; magnetic tunnel junction; perpendicular magnetic anisotropy; spintronics; thermal stability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2013.2251326

Filename

6558971