Scaling the SOT track – A path towards maximizing efficiency in SOT-MRAM

We demonstrate, for the first time, the functionality of a scaled perpendicular spin-orbit torque (SOT)-MRAM where the SOT layer and magnetic tunnel junction (MTJ) pillar exhibit comparable dimensions. This novel design leads to a significant reduction in the power consumption (63% decrease), an enhancement in endurance (>10
¹⁵
cycles), and a reduction in bit-cell area. Systematic investigations on device scaling are performed, highlighting the importance of SOT track scaling as a path to enhance the device performance by eliminating power consumption outside the MTJ pillar region. Furthermore, the hybrid free layer stack design offers a potential solution for scaling MTJ dimensions, as it enables low switching current and sufficient retention down to 20 nm.