TUNNELING MAGNETORESISTIVE ELEMENT INCLUDING MULTILAYER FREE MAGNETIC LAYER HAVING INSERTED NONMAGNETIC METAL SUBLAYER

摘要

A tunnel magnetoresistive element includes a laminate including a pinned magnetic layer, an insulating barrier layer, and a free magnetic layer. The insulating barrier layer is composed of Ti—Mg—O or Ti—O. The free magnetic layer includes an enhancement sublayer, a first soft magnetic sublayer, a nonmagnetic metal sublayer, and a second soft magnetic sublayer. For example, the enhancement sublayer is composed of Co—Fe, the first soft magnetic sublayer and the second soft magnetic sublayer are composed of Ni—Fe, and the nonmagnetic metal sublayer is composed of Ta. The total thickness of the average thickness of the enhancement sublayer and the average thickness of the first soft magnetic sublayer is in the range of 25 to 80 angstroms. Accordingly, the tunneling magnetoresistive element can consistently have a higher rate of resistance change than before.