Magnetoresistive stack and methods therefor

A magnetoresistive device, comprising:

• a tunnel barrier region;
• a magnetically fixed region positioned on one side of the tunnel barrier region, the magnetically fixed region including a synthetic antiferromagnetic (SAF) structure;
• a magnetically free region positioned on an opposite side of the tunnel barrier region;
• a first transition region;
• and
• a second transition region,
• wherein the first transition region and the second transition region are positioned between the tunnel barrier region and the magnetically fixed region.

A magnetoresistive device, comprising:

• a seed region;
• a magnetically fixed region over the seed region;
• a first transition region over the magnetically fixed region, the first transition region including a non-ferromagnetic transition metal;
• a second transition region over the first transition region, the second transition region including an alloy including iron (Fe) and boron (B), and
• a tunnel barrier region over the second transition region.