Patent ID: 6893741
Filing Date: 2005-05-17
Classification: B82Y,G01R,G11B,G11C,H01F,H01L,Y10T

Abstract:
1. A magnetoresistive spin valve sensor comprising: a substrate; a fixed ferromagnetic layer formed on the substrate and having its magnetization direction pinned in the absence of an applied magnetic field; a nonmagnetic metallic electrically conducting spacer layer in contact with the fixed ferromagnetic layer; and a free ferromagnetic layer in contact with the spacer layer and having its magnetization direction free to rotate relative to the magnetization direction of the fixed ferromagnetic layer; and wherein at least one of the fixed and free ferromagnetic layers comprises first and second ferromagnetic films antiferromagnetically coupled to one another and an antiferromagnetically coupling film located between and in contact with the first and second ferromagnetic films and having a thickness sufficient to couple the first and second ferromagnetic films together with their magnetic moments oriented antiparallel to one another, the antiferromagnetically coupling film being formed of a material consisting essentially of Ru and Fe and having a composition Ru