Field Dependence of Spin-Transfer Torque Switching Current in Perpendicular Magnetic Tunnel Junctions

Author

Cuchet, Lea ; Sousa, Ricardo C. ; Vila, Laurent ; Auffret, Stephane ; Rodmacq, Bernard ; Dieny, Bernard

Author_Institution

SPINTEC, CEA, Grenoble, France

Volume

50

Issue

11

fYear

2014

fDate

Nov. 2014

Firstpage

1

Lastpage

4

Abstract

Spin-transfer torque switching has been studied on (Co/Pt)/Ta/CoFeB/MgO/FeCoB/Ta patterned perpendicular magnetic tunnel junctions with nanopillar diameters ranging between 100 and 300 nm. Plotting current-field state diagrams, the critical current density for writing was found to be around 3 MA· cm^-2. The field-current dependence of the state transition boundary is linear, with the slope depending on material parameters. Using different thicknesses of top FeCoB free layers, we were able to estimate the Gilbert damping parameter α .

Keywords

boron alloys; cobalt; cobalt alloys; iron alloys; magnesium compounds; magnetic multilayers; magnetic switching; magnetic tunnelling; nanomagnetics; nanostructured materials; perpendicular magnetic anisotropy; platinum; tantalum; Co-Pt-Ta-CoFeB-MgO-FeCoB-Ta; Gilbert damping parameter; critical current density; current-field state diagrams; field-current dependence; nanopillar diameters; patterned perpendicular magnetic tunnel junctions; size 100 nm to 300 nm; spin-transfer torque switching current; state transition boundary; Anisotropic magnetoresistance; Critical current density (superconductivity); Current measurement; Junctions; Magnetic tunneling; Magnetomechanical effects; Switches; Magnetoresistive random access memories (MRAMs); perpendicular magnetic anisotropy (PMA); spin-transfer torque (STT) switching;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2014.2322390

Filename

6971794