K. Mizunuma

TL;DR: Inter interfacial perpendicular anisotropy between the ferromagnetic electrodes and the tunnel barrier of the MTJ is used by employing the material combination of CoFeB-MgO, a system widely adopted to produce a giant tunnel magnetoresistance ratio in MTJs with in-plane an isotropy.

TL;DR: In this paper, the junction size dependence of critical current for spin transfer torque switching and thermal stability factor (E/kBT) was examined in CoFeB/MgO perpendicular magnetic tunnel junctions (p-MTJs).

Abstract: The authors studied an effect of ferromagnetic (Co20Fe60B20 or Fe) layer insertion on tunnel magnetoresistance (TMR) properties of MgO-barrier magnetic tunnel junctions (MTJs) with CoFe/Pd multilayer electrodes TMR ratio in MTJs with CoFeB/MgO/Fe stack reached 67% at annealing temperature (Ta) of 200 °C and then decreased rapidly at Ta over 250 °C The degradation of the TMR ratio may be related to crystallization of CoFe(B) into fcc(111) or bcc(011) texture resulting from diffusion of B into Pd layers MTJs which were in situ annealed at 350 °C just after depositing bottom CoFe/Pd multilayer showed TMR ratio of 78% by postannealing at Ta=200 °C

TL;DR: In this article, the dependence of magnetic anisotropy in CoFeB-MgO on the MgO layer thickness was investigated and it was shown that a clear perpendicular magnetic easy axis is obtainable in a 1.5-nm thick CoFe b layer by depositing Mg o of more than three monolayers.

TL;DR: In this article, the authors review recent developments in magnetic tunnel junctions with perpendicular easy axis (p-MTJ) for nonvolatile very large scale integrated circuits (VLSIs).