The progresses of MRAM as a memory to save energy consumption and its potential for further reduction

Critical switching current, I<sub>sw</sub>, of STT (Spin Transfer Torque)-MRAM has been reduced by several orders with perpendicular MTJ and the state-of-the-art write charge, Q<sub>w</sub>, becomes the order of 100-150fC. With the small Q<sub>w</sub>, MRAM starts to save energy consumption by 70-80% compared with a conventional memory system. Analysis of the write pulse-width dependence of I<sub>w</sub> revealed a further potential of perpendicular MTJ to reduce I<sub>w</sub> and Q<sub>w</sub>. STT-MRAM is thought to achieve a further reduction of energy consumption.