Patent ID: 7529065
Filing Date: 2009-05-05
Classification: G11B

Abstract:
1. A thin film magnetic recording medium for perpendicular recording comprising: a first thin film magnetic layer with a preferred anisotropy orientation perpendicular to a plane of the thin film, the first thin film magnetic layer having at least a first set of magnetic domains recording a first bit of information and a first set of noise domains adjacent to the first set of magnetic domains; a second thin film magnetic layer with a preferred anisotropy orientation perpendicular to a plane of the thin film, the second thin film magnetic layer being nearer to a surface of the recording medium than the first thin film magnetic layer, the second thin film magnetic aver having a second set of magnetic domains recording the first bit of information and having a remanent state of magnetization parallel to a remanent state of magnetization of the first set of magnetic domains in the first thin film magnetic layer, and having a second set of noise domains adjacent to the second set of magnetic domains; and a spacer layer separating the first and second thin film magnetic layers that achieves an antiferromagnetic coupling field between the first and second thin film magnetic layers, the antiferromagnetic coupling field being insufficient to cause the first and second sets of magnetic domains to switch to antiparallel states in a remanent state, and the antiferromagnetic coupling field decreasing a correlation between first and second sets of noise domains, relative to structure without said antiferromagnetic coupling field.