A current perpendicular to plane dual giant magnetoresistive sensor (dual
CPP GMR sensor) that prevents spin torque noise while having high dR/R
performance. The sensor has a design that maximizes the GMR effect (dR/R)
by providing a pinned layer structure that maximizes the positive GMR
contribution of the AP2 layer (or magnetic layer closest to the spacer
layer) while minimizing the negative GMR contribution of the AP1 layer.
The pinned layer structure includes an AP1 layer that includes a thin
CoFe layer that is exchange coupled with an IrMn or IrMnCr AFM layer and
has two or more Co layers with a spin blocking layer sandwiched between
them. The use of the Co layers and the spin blocking layer in the AP1
layer minimizes the negative contribution of the AP1 layer. The AP2 layer
has a plurality of CoFe layers with nano-layers such as Cu sandwiched
between the CoFe layers.