MAGNETORESISTIVE EFFECT ELEMENT, AND MAGNETIC RANDOM ACCESS MEMORY, AND ITS INITIALIZATION METHOD

摘要

A magnetoresistive effect element and a magnetic random access memory comprise a first ferromagnetic layer, an insulating layer provided contiguously thereto, a second ferromagnetic layer provided on the side opposite to the first ferromagnetic layer contiguously to the insulating layer, and at least two third ferromagnetic layers provided near the both ends of the first ferromagnetic layer in the longitudinal direction in contact therewith magnetically. The first through third ferromagnetic layers have magnetic anisotropy in the direction substantially perpendicular to the film surface. The magnetoresistive effect element and the magnetic random access memory are initialized by making the external magnetic field fall down after applying a sufficiently large external magnetic field in the film surface direction thereby introducing a magnetic domain wall in the first ferromagnetic layer. A magnetic random access memory in which the current value required for writing is reduced significantly as compared with 1 mA while maintaining sufficient thermal stability and resistance against disturbance magnetic field, and the memory state can be initialized by an easy process can thereby be provided.