Spin valve sensor with magnetic and nonmagnetic layers for improving asymmetry and softness of a free layer structure

摘要

A nonmagnetic conductive layer is provided on top of a free layer structure for at least counterbalancing sense current fields from conductive layers below the free layer structure so as to improve readback asymmetry of the spin valve sensor. Further, a magnetic conductive layer is provided on top of the nonmagnetic conductive layer for at least partially counterbalancing a demagnetizing field emanating from a pinned layer structure below the free layer structure. The nonmagnetic conductive layer, which is preferably copper (Cu), isolates the magnetization of the magnetic conductive layer from the free layer structure and also improves the soft magnetic properties of the free layer structure.