Excellent Temperature Dependence of Retention Energy and Large Tunnel Magnetoresistance of MTJs With Strain-Induced Magnetic Anisotropy for SOT-MRAMs With High Write Efficiency

Temperature dependence of retention energy of MTJs with strain-induced magnetic anisotropy (SIMA-MTJs) was estimated by performing repeated measurements on the coercivity of the storage layer and fitting the switching probability data obtained from them with Sharrock’s formula. The retention energy of SIMA-MTJs at
$85~^{\circ }$
C increased by 14% compared with that at room temperature on average. Also, over 300% of tunnel magnetoresistance (TMR) was demonstrated with 1.9 nm-thick storage layer. Furthermore, it was estimated that the switching current for 1.9 nm-thick storage layer can be lowered to the level of
$20~\mu $
A with a retention energy of 80 kBT by practically available values of interface magnetic anisotropy,
$K_{s} =1.6$
erg/cm2, and spin-Hall angle of 0.3.