[16a-D704-1~10] 10.3 Spin devices, magnetic memories and storages

▼ [16a-D704-8] TaFeB spacer for soft magnetic composite free layer in CoFeB/MgO/CoFeB-based
magnetic tunnel junction

〇Takafumi Nakano¹, Kosuke Fujiwara², Seiji Kumagai², Yasuo Ando^1,3, Mikihiko Oogane^1,3 (1.Tohoku Univ., 2.SSF Corp., 3.CSIS)

Keywords:Magnetic tunnel junction, Tunnel magnetoresistance, Magnetic sensor

CoFeB/MgO/CoFeB-based magnetic tunnel junctions (MTJs) with a soft magnetic composite free layer have been developed for magnetic sensor applications. Tunnel magnetoresistance (TMR) ratios in the sensor-type MTJs have reached a ceiling due to a trade-off between the TMR ratio and interlayer exchange coupling (IEC) depending on the spacer thickness of the composite free layer. In this study, we developed a paramagnetic amorphous TaFeB-alloy spacer to replace the conventional Ta spacer and solve this trade-off.