Impact of Sub-Volume Excitation for Improving Overdrive Delay Product in Sub-40nm p-MTJ and Its Beyond

We investigated the impact of sub-volume effect on improving the overdrive delay product Pod in sub-40nm p-MTJ and its beyond using LLG micro magnetic simulation. Simulation results show over 26 percent reduction of the overdrive delay product by suppressing sub-volume excitation. We found the overdrive delay product can be reduced by scaling down junction diameter or enlarging exchange stiffness. These results show that p-MTJ of embedded MRAM should be scaled down under 40nm to suppress sub-volume excitation, not only for high-density but also for high speed programing.