Spintronic devices, especially electric-field and spin–orbit torque driven magnetic tunnel junctions (MTJs), are promising candidates to replace the current memory and logic components for satisfying future computing demands. Current spin–orbit torque based MTJ devices with a single free layer and spin Hall channel still face high current density for switching. Here, 150-nm perpendicular MTJs are designed and fabricated with a synthetic-antiferromagnetic free layer and a bilayered spin Hall channel. The switching behavior is investigated via combination of forces from electric-field and spin–orbit torque, where the electric field can modulate the exchange coupling of the synthetic-antiferromagnetic free layer. Through an assistance of spin–orbit torque, bidirectional switching is obtained with switching current density as low as 3 × 103 A cm−2, which is two orders of magnitude lower than that of the current best reported values. These results suggest that electric-field switching of synthetic-antiferromagnetic MTJs could be a promising approach for reducing write current density of spintronic devices.
Bibliographical noteFunding Information:
B.R.Z. and D.Z. contributed equally to this work. This work is currently supported by ASCENT, one of six centers of JUMP, a Semiconductor Research Corporation program that is sponsored by MARCO and DARPA, and DARPA HR001117S0056‐FP‐042 “Advanced MTJs for computation in and near random access memory.” Portions of this work were conducted in the Minnesota Nano Center, which is supported by the National Science Foundation through the National Nano Coordinated Infrastructure Network (NNCI) under Award Number ECCS‐1542202.
© 2022 The Authors. Advanced Electronic Materials published by Wiley-VCH GmbH.
- electric-field (voltage-controlled exchange coupling)
- energy-efficient spin–orbit torque devices
- perpendicular magnetic tunnel junctions
- synthetic antiferromagnetic free layers