Development of Highly Manufacturable, Reliable, and Energy-Efficient Spin-Orbit Torque Magnetic Random Access Memory (SOT-MRAM)

We demonstrate highly manufacturable, reliable, and energy-efficient SOT-MRAM by developing damage-free reactive-ion etching (RIE) recipes. The experimental results demonstrate that C-F Etch lowers the CoFeB/MgO interfacial anisotropy, partially destroys the magnetic moment of CoFeB, and the post-etch annealing further degrades the magnetic moment. On the other hand, N-H Etch hardly changes the stack magnetic property. The present process technology allows to etch uniformly stop on the thin heavy-metal (HM) layer and resulting in a low SOT-channel resistance <250Ω. A statistical full wafer-level study of the SOT switching properties such as TMR%, SOT-channel resistance, P2AP/AP2P voltages, and P/AP-state resistances has been explored.