High efficient spin transfer torque writing on perpendicular magnetic tunnel junctions for high density MRAMs

Abstract An Fe-based perpendicular alloy with small damping constant was applied to an MTJ storage layer and small switching current of 9 μA was obtained for a write current width of 5 ms. The efficiency of spin transfer torque writing was proved to be higher than those for in-plane MTJs. The estimated Ic for the MTJ with 50 nsec pulse width is lower than 20 μA and smaller than the drive currents of CMOS transistor at Gbits density.