Patent ID: 6597542
Filing Date: 2003-07-22
Classification: B82Y,G01R,G11B,H01F,Y10T

Abstract:
A dual spin-valve magnetoresistive thin film element, comprising;a composite free magnetic layer including a first free magnetic layer and a second free magnetic layer with a nonmagnetic intermediate layer therebetween; first and second nonmagnetic electrically conductive layers, wherein said first nonmagnetic electrically conductive layer resides below said composite free magnetic layer and wherein said second nonmagnetic electrically conductive layer overlies said composite free magnetic layer; first and second dual pinned magnetic layers, each of said first and second dual pinned magnetic layers including a first pinned magnetic layer and a second pinned magnetic layer separated by a nonmagnetic intermediate layer, wherein said first dual pinned magnetic layer resides below said first nonmagnetic electrically conductive layer, and wherein said second dual pinned magnetic layer overlies said second nonmagnetic electrically conductive layer; first and second antiferromagnetic layers, wherein said first antiferromagnetic layer resides below said first dual pinned magnetic layer, and wherein said second antiferromagnetic layer overlies second dual pinned magnetic layer; wherein said first pinned magnetic layer of said first dual pinned magnetic layer contacts said first antiferromagnetic layer, and wherein said second pinned magnetic layer of said first dual pinned magnetic layer contacts said first nonmagnetic electrically conductive layer; wherein said first pinned magnetic layer of said second dual pinned magnetic layer contacts said second antiferromagnetic layer, and wherein said second pinned magnetic layer of said second dual pinned magnetic layer contacts said second nonmagnetic electrically conductive layer; wherein a magnetic moment of said first pinned magnetic layer in said first dual pinned magnetic layer is greater than a magnetic moment of said second pinned magnetic layer in said first dual pinned magnetic layer; wherein a magnetic moment of said first pinned magnetic layer in said second dual pinned magnetic layer is smaller than a magnetic moment of said second pinned magnetic layer in said second dual pinned magnetic layer; wherein each of said magnetic moments is a product of a saturation magnetization Ms and a film thickness t of each of said pinned magnetic layers; wherein a pinned magnetization of said first pinned magnetic layers in said first and second dual pinned magnetic layers are facing in opposite directions; wherein said pinned magnetization of said first pinned magnetic layer and a pinned magnetization of said second pinned magnetic layer in said first dual pinned magnetic layer are facing in opposite directions, wherein said pinned magnetization of said first pinned magnetic layer and a pinned magnetization of said second pinned magnetic layer in said second dual pinned magnetic layer are facing in opposite directions, wherein said pinned magnetization of said second pinned magnetic layers in said first and second dual pinned magnetic layers are facing in opposite directions, and wherein a magnetization of said first and second free magnetic layers are facing in opposite directions.