A Novel STT-MRAM Design with Electric-Field-Assisted Synthetic Anti-Ferromagnetic Free Layer

Spin-transfer torque magnetic random-access memory (STT-MRAM) is one of the next-generation nonvolatile memories, which has the most promising industrial prospect and has generated lots of new ideas. One of the continuous challenges in STT-MRAM development is to reduce the critical write current. Recently, one published paper reported that under a small electric bias voltage, the synthetic anti-ferromagnetic (SAF) multilayer system could be switched between an anti-ferromagnetic coupling state and a ferromagnetic coupling state. Based on this phenomenon, we propose a new type of STT-MRAM of which the critical write current can be reduced by an assisting electric-field (E-field). Micromagnetic simulation has been performed to study the dynamic switching behavior of the magnetization of the SAF free layer with tunable Ruderman-Kittel-Kasuya-Yosida interaction under the impact of an E-field.