25 nm iPMA-type Hexa-MTJ with solder reflow capability and endurance > 107 for eFlash-type MRAM

We proposed and developed a solder reflow capable interfacial perpendicular magnetic anisotropy Hexa CoFeB/MgO-interfaces magnetic tunnel junction (iPMA-type Hexa-MTJ) with BEOL process compatibility. The 25 nm iPMA-type Hexa-MTJ with the newly developed free, reference, and MgO layers simultaneously realized a small temperature dependence of thermal stability factor $\Delta$, a sufficiently large iPMA for solder reflow capability, and a large TMR ratio with low resistance. In addition, the iPMA-type Hexa-MTJ achieved write endurance of 10
⁷
at least with a 100 ns write pulse. As a result, the iPMA-type Hexa-MTJ will realize seamless scaling for eFlash-type MRAM based on the latest X nm CMOS technology.