Spin-Orbit-Torque Switching in 20-nm Perpendicular Magnetic Tunnel Junctions

Magnetization switching using spin-orbit torque (SOT) is an interesting candidate for future MRAM applications, and several studies have analyzed its performance versus standard technology based on spin-transfer torque (STT). However, progress in small devices is impeded mostly by challenges in making small interconnects and measuring tiny Hall voltages. This study uses conductive atomic force microscopy to measure tunnel magnetoresistance and demonstrate deterministic SOT switching in thermally stable 20-nm structures. Estimates based on measured switching currents suggest that SOT switching is more energy efficient than conventional STT technology.