| Abstract: | We report a perpendicular magnetic tunnel junction(p MTJ) cell with a tunnel magnetoresistance(TMR) ratio of nearly 200% at room temperature based on Co Fe B/Ta/Co Fe B as the free layer(FL) and a synthetic antiferromagnetic(SAF) multilayer [Pt/Co]/Ru/[Pt/Co]/Ta/Co Fe B as the reference layer(RL). The field-driven magnetization switching measurements show that the p MTJs exhibit an anomalous TMR hysteresis loop. The spin-polarized layer Co Fe B of SAF-RL has a lower critical switching field than that of FL. The reason is related to the interlayer exchange coupling(IEC) through a moderately thick Ta spacer layer among SAF-RLs, which generates a moderate and negative bias magnetic field on Co Fe B of RL. However, the IEC among RLs has a negligible influence on the current-driven magnetization switching of FL and its magnetization dynamics. |
