Tunneling magnetic sensing element including enhancing layer having high Fe concentration in the vicinity of barrier layer

摘要

A tunneling magnetic sensing element is provided, in which an increase in the magnetostriction of a free magnetic layer is reduced and the rate of change in resistance is high. A laminate T1 constituting the tunneling magnetic sensing element includes a portion in which a pinned magnetic layer, a barrier layer, and a free magnetic layer are disposed in that order from the bottom. An enhancing layer disposed on the barrier layer side of the free magnetic layer includes a first enhancing layer on the barrier layer side and a second enhancing layer on the soft magnetic layer side, and the Fe content of a CoFe alloy constituting the first enhancing layer is specified to be larger than the Fe content of the CoFe alloy of the second enhancing layer.