In magnetic tunneling junction MRAM devices, write addressing of each indiv
idual memory element is accomplished by using an x-y grid of word lines, wh
ich generate easy and hard axis fields. In this paper, we present a systema
tic micromagnetic modeling study of switching behavior with both easy and h
ard axis fields for memory elements with ends tapered into various angles a
nd at different aspect ratios. The write margin and addressability will be
discussed.