Patent ID: 6882510

Claim:
A magnetic head including a magnetoresistive sensor comprising: a pinned ferromagnetic layer structure; a free ferromagnetic layer structure; and a nonmagnetic spacer layer located between the pinned and free ferromagnetic layers structures; and wherein at least one of the pinned and free ferromagnetic layers structure includes: first and second ferromagnetic films; an antiferromagnetic coupling (AFC) film located between and in contact with said first and second ferromagnetic films, said AFC film comprising an alloy material selected from the group consisting of Ru 100-x m x , Os 100-y m y , Ir 100-y m y , Rh 100-y ,m y , Re 100-z m z , and M 100-x m x , where M is an alloy of two or more materials selected from the group consisting of Ru, Os, Ir, Rh, and Re, and where m is a material selected from the group consisting of W, Ta, Mo, Nb and alloys of two or more materials selected from W, Ta, Mo, and Nb, and where x is between approximately 5 and 95 at. %, y is between approximately 10 and 90 at. %, and z is between approximately 25 and 75 at. %.